Effect of oxygenates in gasoline on fuel
consumption and emissions in three Euro
4 passenger cars
Final Report
Authors
G. Martini, U. Manfredi, A. Krasenbrink
Joint Research Centre- Institute for Energy
and Transport
R. Stradling, P.J. Zemroch, K. D. Rose
CONCAWE
H. Hass, H. Maas
EUCAR
2013
Report EUR 26381 EN
European Commission
Joint Research Centre
Institute for Energy and Transport
Contact information
Giorgio Martini
Address: Joint Research Centre, Via Enrico Fermi 2749, TP 441, 21027 Ispra (VA), Italy
E-mail: [email protected]
Tel.: +39 0332 78 9293
Fax: +39 0332 78 5236
http://iet.jrc.ec.europa.eu/
http://www.jrc.ec.europa.eu/
This publication is a Reference Report by the Joint Research Centre of the European Commission.
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JRC86439
EUR 26381 EN
ISBN 978-92-79-34883-9 (pdf)
ISBN 978-92-79-34884-6 (print)
ISSN 1831-9424 (online)
ISSN 1018-5593 (print)
doi: 10.2790/1136
Luxembourg: Publications Office of the European Union, 2013
© European Union, 2013
Reproduction is authorised provided the source is acknowledged.
Printed in Italy
JRC/EUCAR/CONCAWE Study on:
Effect of oxygenates in gasoline on
fuel consumption and emissions
in three Euro 4 passenger cars
Authors:
G. Martini, U. Manfredi, A. Krasenbrink
European Commission, Joint Research Centre, Institute for
Environment and Sustainability
R. Stradling, P. J. Zemroch, and K. D. Rose
CONCAWE
H. Hass, H. Maas
EUCAR
Acknowledgements
The authors would like to acknowledge the essential
contribution of the staff of the JRC VELA laboratory:
P. Le Lijour, G. Lanappe, M. Sculati, R. Colombo
As well as the help and input from others who advised on the
study, specifically:
EUCAR: Expert Group Fuels
CONCAWE’s Gasoline Special Task Force (FE/STF-20)
Contents
Special Terms and Abbreviations .............................................................................................................................................................. 5
1.
EXECUTIVE SUMMARY ................................................................................................................................................................. 7
2.
BACKGROUND ................................................................................................................................................................................. 8
3.
STUDY OBJECTIVES ....................................................................................................................................................................... 9
4.
VEHICLE TESTING PROTOCOL .................................................................................................................................................. 9
5.
EXPERIMENTAL SET-UP ............................................................................................................................................................... 9
5.1. Emissions test facility .......................................................................................................................................................................... 9
5.2. Fuel consumption .............................................................................................................................................................................. 11
5.3. Test vehicles ....................................................................................................................................................................................... 11
5.4. Test vehicle preparation ................................................................................................................................................................... 12
5.5. Test cycles .......................................................................................................................................................................................... 13
5.6. Test cycles .......................................................................................................................................................................................... 14
6.
PROGRAMME STRUCTURE ........................................................................................................................................................ 17
6.1. Test protocol ...................................................................................................................................................................................... 17
6.2. Daily testing schedule ........................................................................................................................................................................ 18
6.3. Statistical data analysis ..................................................................................................................................................................... 18
7.
TEST RESULTS ............................................................................................................................................................................... 19
7.1. CO2 emissions, fuel consumption, and energy ................................................................................................................................ 19
7.2. Exhaust emissions ............................................................................................................................................................................. 22
7.3. Effects of fuel properties on exhaust emissions .............................................................................................................................. 24
8.
RESULTS AND CONCLUSIONS ................................................................................................................................................... 25
9.
REFERENCES .................................................................................................................................................................................. 27
APPENDIX 1
FUEL PROPERTIES ................................................................................................................................................. 28
APPENDIX 2
DETAILS OF THE TEST PROCEDURE ............................................................................................................... 30
APPENDIX 3
ADDITIONAL FUEL CONSUMPTION RESULTS .............................................................................................. 48
APPENDIX 4
PM AND PN EMISSIONS ......................................................................................................................................... 53
APPENDIX 5
AVERAGE FUEL EFFECTS ON REGULATED EMISSIONS ........................................................................... 55
APPENDIX 6
UNCORRECTED AND CORRECTED RESULTS ................................................................................................ 57
Special Terms and Abbreviations
ASTM
CEN
CO
CO2
CONCAWE
CVS
DG
DI
DISI
DNPH
DVPE
EC
EMS
EN
EPA
EPEFE
ETBE
EU
EUCAR
EUDC
EURO 4
FC
FID
GC
GC-MS
GHG
kPa
HC
HPLC
IES
IR
JEC
JRC
LD
LHV
MJ
MON
MPI
MS
m/z
NEDC
NOx
PFI
PM
PMP
PN
ppm
RED
RON
rpm
SFTP
SG
American Society for Testing and Materials
European Committee for Standardization
Carbon Monoxide
Carbon Dioxide
The Oil Companies’ European Association for Environment, Health
and Safety in Refining and Distribution
Constant Volume Sampling System
Directorate General
Direct Injection
Direct Injection Spark Ignition
2,4-Dinitrophenylhydrazine
Dry Vapour Pressure Equivalent (in kPa, measured at 37.8°C)
European Commission
Engine Management System
European Norm issued by CEN
Environmental Protection Agency (USA)
European Programme on Emissions, Fuels and Engine Technologies
Ethyl Tertiary Butyl Ether
European Union
European Council for Automotive R&D
Extra Urban Driving Cycle (Part 2 of the NEDC Type 1 test)
European emissions standard
Fuel Consumption
Flame Ionization Detector
Gas Chromatography
Gas Chromatography-Mass Spectrometry
Greenhouse Gas
1 KiloPascal = 1000 N/m2
Hydrocarbons
High performance liquid chromatography
Institute of Environment and Sustainability (JRC)
Infrared Spectroscopy
JRC/EUCAR/CONCAWE Research Consortium
Joint Research Centre
Light Duty
Lower Heating Value
Megajoule
Motor Octane Number
Multi Point Injection
Mass Spectrometry
Mass to charge ratio for detected ions in mass spectrometry
New European Driving Cycle (Type 1 test)
Nitrogen Oxides
Port Fuel Injection
Particulate Matter or Particulate Mass
Particulate Measurement Programme
Particle Number
parts per million
Renewable Energy Directive (2009/28/EC)
Research Octane Number
revolutions per minute
Supplemental Federal Test Procedure
Specific Gravity
THC
TWC
Type 1 Test
UDC
USA
US06
VELA
VLHV
VOC
VVT
WTW
Total Hydrocarbons
Three-Way Catalyst
Type of emission test as laid down in the Directive 70/220/CEE and
subsequent amendments
Urban Driving Cycle (Part 1 of the NEDC Type 1 Test)
United States of America
US SFTP driving cycle that represents aggressive, high speed and/or
high acceleration driving, rapid speed fluctuations, and driving
behaviour following start-up
Vehicles Emission Laboratory (JRC)
Volumetric Lower Heating Value
Volatile Organic Compound
Variable Valve Timing
Well-to-Wheels
1. EXECUTIVE SUMMARY
The Joint Research Centre (JRC) of the European Commission, the European Council for Automotive R&D
(EUCAR), and CONCAWE jointly completed this vehicle test programme to investigate the effect of
oxygenates in gasoline on the fuel consumption, regulated emissions, and particle emissions of three
passenger cars homologated at the Euro 4 emissions level.
Substituting oxygenates for hydrocarbons in gasoline decreases the overall energy content of the resulting
blend which is also expected to increase the volumetric fuel consumption needed to achieve the same
vehicle driving cycle. For this reason, a major objective of this study was to determine whether today’s
gasoline vehicles can improve their efficiency when running on oxygenate/gasoline fuel blends and reduce
this volumetric fuel consumption penalty by taking advantage of either higher Research Octane Number
(RON) or the properties of the oxygenate, such as the latent heat of vaporisation for ethanol.
In addition to a 95 RON base gasoline, five other specially blended fuels were evaluated that varied in RON,
oxygen content, and oxygenate type. Results are compared for the New European Driving Cycle (NEDC), the
US06 part of the US Supplemental Federal Test Procedure (SFTP), and three constant speeds.
Over all vehicle test conditions, the results show that the volumetric fuel consumption (FC) changes in
direct proportion to the fuel’s volumetric energy content with higher volumetric energy contents resulting
in better FC. Except possibly for one vehicle over one test cycle, the results show that the use of oxygenates
or higher octane did not provide a volumetric FC benefit. This means that these Euro 4 passenger cars were
not able to compensate for the lower energy content of oxygenated fuels through better engine efficiency
for the variation in fuel properties investigated in this study.
For the regulated pollutant emissions, all three vehicles complied with the Euro 4 emissions limits for NOx,
CO, and total hydrocarbons (THC) over the NEDC. Fuel properties had little effect on these emission levels
even though RON, oxygen content, and oxygenate type were widely varied. Driving cycle and vehicle
technology were found to have a much greater impact on these regulated pollutants compared to fuel
properties.
The three Euro 4 vehicles tested in this study were not required to meet any particle emissions limits for
particulate mass (PM) or particle number (PN). Nonetheless, the effects of driving cycle and fuel properties
on particle emissions are of general interest and were measured in this study using the Particulate
Measurement Programme (PMP) protocols. Driving cycle and vehicle technology were found to have a
much greater impact on PM and PN emissions compared to fuel properties.
2. BACKGROUND
The Renewable Energy Directive (RED, 2009/28/EC) established a common European framework for the
promotion of energy from renewable sources [3]. This Directive set mandatory national targets for the
overall share of renewable energy in the gross final consumption of energy and for the share of renewable
energy in transport. For the transport sector, each Member State must ensure that the share of energy from
renewable sources in all forms of transport is at least 10% of the final energy consumption in transport in
that Member State by 2020.
Although the RED set overall targets for energy from renewable sources, biofuels blended into fuels are
expected to play an important role to achieve these targets, especially in the transport sector. However, to
comply with the RED targets, the biofuels used in transport fuels must be certified as sustainably produced
and fulfil certain sustainability criteria.
Considerable progress has been made in understanding the Well-to-Wheels (WTW) energy and
greenhouse gas (GHG) impacts of biofuels including bioethanol, with the JEC WTW study [9] making a
notable contribution in the European context. Today, bioethanol is the most widely used biofuel in the
world. Bioethanol, and associated bio-products such as ETBE, are most widely used in low level blends
with gasoline (E5, E10, etc.) while higher level blends are very popular in some countries (for example,
Sweden and Brazil). The use of bioethanol and its ether product in petrol are considered by many to be an
important option to achieve the RED target of reaching a 10% share of renewable energy in European
transport by 2020. In fact, compared to biodiesel, the potential production of ethanol is higher due to the
larger range of sustainable biomass sources from which this product can be manufactured.
In most WTW studies (including the JEC study [9]), it is usually assumed that the vehicle's energy efficiency
remains unchanged when running on an oxygenated fuel; that is, the same Megajoules (MJ) of fuel energy
are required to complete a prescribed driving cycle whether the fuel is hydrocarbon-only or an
oxygenate/hydrocarbon blend. The consequence of this assumption is that a higher volumetric fuel
consumption is expected for the oxygenated blend, because the volumetric energy content of the oxygenate
component is generally lower than that of the hydrocarbon-only fuel into which the oxygenate is blended.
This view has been challenged by some studies that suggest that the fuel consumption penalty may be less
than expected based on the above reasoning. This question has become more important as attention
focuses more closely on the actual WTW GHG savings that can be achieved from biofuels.
Beyond the available references, there are some potentially plausible mechanisms why the volumetric fuel
consumption of an oxygenate/gasoline blend might or might not increase in proportion to the oxygenate
concentration in the blend:

The latent heat of ethanol is higher than that of gasoline. This could potentially affect the volumetric
efficiency of the engine (by cooling the charge and hence allowing a greater mass of air to be
inducted). This in turn could affect engine power and fuel consumption.

Oxygenates, including ethanol and ether, have inherently high octane numbers. Depending on how
oxygenate blends are introduced into the market, the octane of the finished fuel could increase, or
the hydrocarbon portion of the fuel could be reformulated, resulting in the same octane level as a
hydrocarbon-only fuel. If the octane of the blend is higher, some vehicles may be able to advance
ignition timing, giving a small improvement in fuel consumption at knock-limited operating
conditions.
A review of the literature does not, however, allow a clear conclusion to be reached due to the lack of
rigour, incomplete reporting and insufficient testing in most of the available studies [10]. For this reason, a
test programme was carried out to provide more detailed data on modern European vehicles. This test
programme also provided the opportunity to gather data on the related question of oxygenate blend
performance with respect to exhaust emissions over two regulatory driving cycles and three steady state
conditions.
3. STUDY OBJECTIVES
This vehicle study was designed to investigate the effect of octane and oxygenates in gasoline on fuel
consumption, energy efficiency and exhaust emissions of three passenger car models marketed in Europe
complying with Euro 4 emissions limits. Exhaust emissions and fuel consumption were measured
according to the European legislative test procedure for type approval, the New European Driving Cycle
(NEDC), as defined in the related European legislation (Directive 98/69/EC, Annex IV and 80/1268/EEC
and subsequent amendments [2]). Additional tests were performed at three steady-state speeds and over
the US06 part of the Supplemental Federal Test Procedure (SFTP) used in the USA to represent more
aggressive and high speed driving behaviour.
4. VEHICLE TESTING PROTOCOL
The vehicle testing protocol (see Appendix 2) was defined to provide a robust and repeatable way of
measuring the short-term direct effect of fuels on fuel consumption and regulated emissions. Both
hydrocarbon-only and oxygen-containing fuels were tested in this study in order to evaluate the effect of
oxygenate, especially ethanol, on vehicle emissions and fuel consumption, including measurements of:



CO2 emissions for its own evaluation and (in conjunction with CO and HC emissions) for the
calculation of fuel consumption based on the carbon-balance equation;
Regulated emissions specifically exhaust HC, CO, Total Hydrocarbons (THC), and NOx using the
methods prescribed by the regulatory procedure;
Particulate mass (PM) and particle number (PN) emissions which will be required in future
legislation on some gasoline vehicles.
The test procedure and protocols are based on the well-established EPEFE [8] methods, simplified and
modified where appropriate to the needs of this JEC study. In particular, the importance and potential
impact of vehicle conditioning has been carefully considered with respect to this test programme. When
followed carefully by a qualified laboratory, these procedures ensure sound test data and allow a
statistically valid interpretation of the results, so that the effects of fuel changes on the test vehicle can be
accurately assessed.
It should be noted that fuel effects on emissions can be complex. A key finding of the EPEFE study was that
the same fuel can have different effects in different vehicles, so results obtained on a specific vehicle should
not be generalised to other vehicles.
5. EXPERIMENTAL SET-UP
5.1.
Emissions test facility
This study was carried out in the Vehicle Emissions Laboratory (VELA) of the Joint Research Centre located
in Ispra (Italy). An emissions test facility was used that is in full compliance with the requirements set by
the legislative procedure for vehicle type approval. The facility consists of a climatic chamber, a roller
bench and the equipment for emissions measurements. All tests were carried out at a temperature of 22°C
± 1°C. To follow the legislative driving cycles, the driver was assisted by a driver aid system.
Regulated pollutant emissions were measured in full accordance with the legislative test procedure for
type approval (Type 1 test, UNECE Regulation 83) using a Constant Volume System (CVS) based on a full
flow dilution tunnel with a critical flow Venturi. Gaseous emissions were measured using tedlar bags as
prescribed in the above mentioned test procedure. For the non-legislative cycles, the same methodology
was used.
Emissions were measured using the following analysers/methodologies:





CO: Infrared (IR) analyser
NOx: Chemiluminescence analyser
HC: Flame Ionization Detector (FID) analyser
Particulate Mass (PM): Particulate samples were collected according to the modified procedure
developed in the framework of the Particle Measurement Programme (PMP) and using a Pallflex
TX40HI20 filter (one filter per cycle, no secondary filter). The mass was determined by weighing.
PM emissions were not measured in the steady state tests due to the short sampling period used
which would have resulted in very low mass values
Particle Number (PN): Total PN was measured using a system that was compliant with the
Particulate Measurement Programme (PMP).
Measurements were not performed on the raw exhaust (modal analysis) in order to avoid introducing
errors into the emission measurement. A schematic of the VELA emissions test facility is shown in Figure
1.
Figure 1
Schematic of the VELA emissions test facility
test
fuel
chamber
barometric pressure (~990mbar) chemistry &
composition
humidity (50 ± 5%)
ambient temperature (22 ± 1°C)
density
engine
dynamometer
rpm
distance
H2O
velocity
temp.
oil temp
time
after-catalyst
tem
exhaust
p.
flo
w THC, NOx,
CO,
CO2, O2
(on-line)
fan
catalyst
tail pipe
transfer
line
particle probes
total mass
total particle number (PMP)
bleed-off
temp.
VELA2
37 m3/min
to
vent
VELA1
14 m3/min
flow
temp
pressure
CV
S
~90°C
filter & heat
exchanger
~47°C
DIESEL
GASOLINE
temp. (~25°C)
flow (max. 30 m3/min)
air
conditioning
unit
dilution
air
filter
Tedlar bag:
VOC
DNPH cartridge:
CO,carbonyls
THC, NOx, CO2
humidity
190 °C
(off-line)
temp. (25°C)
gas-phase probes (from bag)
CO, THC, NOx, CO2
(off-line)
blank (from bag)
5.2.
Fuel consumption
UNECE Regulation 101 establishes the methodology to be used to calculate the fuel consumption of
vehicles by measuring exhaust emissions. The calculation is based on the carbon balance method which
requires the measured values of CO2, CO and HC and the knowledge of fuel composition in terms of C/H/O
elemental content. In the type approval test, fuel consumption is calculated using default values for C/H/O
from a typical reference fuel, but this is not appropriate when different fuel compositions are tested,
especially oxygenated fuels. Therefore, data on each fuel’s actual carbon, hydrogen and oxygen contents are
necessary for a correct calculation of fuel consumption. In addition, to calculate the energy used by the
vehicle to complete the driving cycle, the heating value of each test fuel is needed. These data were
calculated for the test fuels from detailed gas chromatography (GC) analyses carried out on each fuel.
The fundamental equation for the carbon balance calculation of fuel consumption is:

FCm = (CWFexh x HC + 0.429 x CO + 0.273 x CO2) / CWFfuel
(in g/km)
where:
 FCm is the calculated fuel consumption in g/km
 CWFexh is the carbon mass (weight) fraction of the HC emissions in g/km
 0.429 is the carbon mass fraction of CO
 CO is Carbon Monoxide emissions in g/km
 0.273 is the carbon mass fraction of CO2
 CO2 is the Carbon Dioxide emissions in g/km
 CWFfuel is the carbon mass (weight) fraction of the fuel
 HC is the Hydrocarbon emissions in g/km
CWFexh is relatively unimportant (and very hard to measure or calculate) because hydrocarbon emissions
from modern vehicles are very low. The correct CWFfuel is critical, however, so the CWFexh was assumed to
equal the CWFfuel. The fuel consumption in l/100km could then be calculated from the following equation:

FCl/100km = (FCm x 100) / (SGfuel x 1000)
where SGfuel is the fuel’s specific gravity in kg/litre.
The energy consumption in MJ/100km is calculated from:

ECMJ/100km = FCl/100km x SGfuel x LHVfuel
where LHVfuel is the fuel’s Lower Heating Value (LHV) in MJ/kg.
5.3.
Test vehicles
Three test vehicles were selected for this study based on the following criteria:



Certified to meet at least Euro 4 emissions limits;
Less than 2 years old and 30,000 km maximum mileage;
The final test fleet had to include the following technologies:
o A port fuel injected (PFI) engine that is typically insensitive to octane
o A variable valve timing (VVT) vehicle to check the effect of throttling
o A vehicle optimised for 98 RON in order to evaluate higher octane numbers and the cooling
effect of ethanol.
The main characteristics of the vehicles selected for this study are shown in Table 1.
Table 1
Test vehicle characteristics
Vehicle
Category
Emission Standard
(homologation)
Engine Size (litres)
Max. Power (kW)
Inertia Class (kg)
Cylinder
Valves
Aspiration
Combustion Type
Injection System
After-treatment device
Year (registration date)
Mileage (km) at start
1
M1
Euro 4
2
M1
Euro 4
3
M1
Euro 4
1.6
85
1250
4
16
VVT
Homogeneous
stoichiometric
MPI
TWC
27/02/2008
20,815
1.6
128
1250
4
16
Turbo
Homogeneous
stoichiometric
DI
TWC
19/04/2008
6,248
1.4
88
1270
4
16
Turbo
Homogeneous
stoichiometric
MPI
TWC
24/09/2008
1,261
When a car was equipped with options that could alter the performance, such as a ‘start-stop’ system or the
possibility to select different driving style (e.g., ‘sport’), these were either deactivated or were not used.
5.4.
Test vehicle preparation
According to the test protocol, the test vehicles had to be in good mechanical condition and preferably had
completed at least 8,000 km on the fuel recommended by the manufacturer prior to testing. This was
required in order to ensure that the catalyst was adequately aged and that the engine combustion chamber
deposits had stabilised.
Vehicle 1 complied with these requirements. Vehicle 3 was a comparatively new vehicle and therefore did
not comply with the minimum mileage requirement. In order to reduce the testing time, the JEC team
agreed to run Vehicle 3 for 3,000 km instead of 8,000 km to stabilize the catalyst. To do this, the vehicle
was driven on the road (mainly highway) until a mileage of 3,000 km had been reached. Vehicle 2 was very
close to the minimum mileage requirement and a similar mileage accumulation was carried out until a
mileage of 7,500 km had been reached.
For all of the vehicles, the engine oil, oil filter, and air filter were changed before starting the test
programme. After the oil change, the oil was aged by driving a minimum of 500 km on the dynamometer.
The fuel used for the oil aging was Fuel 1 from the test fuel matrix. The engine oil complied with the grade
recommended by the vehicle manufacturer.
In addition, the following operations were performed on each vehicle:




The exhaust system of the vehicle was checked for any leaks.
The engine was checked for any leaks of the gasoline/lubricant circuit.
When necessary, additional fittings, adapters or devices were fitted to the fuel system in order to
allow a complete draining of the fuel tank. In general, the draining of the tank was accomplished by
means of the vehicle fuel pump.
When possible, the engine was equipped with suitable thermocouples to monitor the lubricant and
coolant temperature.

Finally, the vehicle’s carbon canister was replaced and a new canister was used that was dedicated
for each test fuel. This means that the canister was replaced at each fuel change to the one that was
dedicated to that test fuel.
5.5.
Test cycles
The pollutant emissions and fuel consumption of the test vehicles were measured over three different
driving cycles:

The New European Driving Cycle (NEDC), which is the legislative cycle for type approval of
European passenger cars (see Figure 2). This is a cold start cycle and all of the tests performed using
this cycle were carried out after the vehicle had experienced an overnight soaking period. The NEDC
consists of two parts: four repeated Urban Driving Cycles (UDC, also ECE-15) and an Extra Urban
Driving Cycle (EUDC).

The US06 part of the US SFTP Driving Schedule, is more representative of aggressive, high speed
and/or high acceleration driving behaviour (see Figure 3). The US06 cycle is a hot start cycle which
requires that the vehicle is run over a pre-conditioning cycle before starting the emission
measurement. According to the US legislation, different cycles can be used for vehicle preconditioning, including the same US06 driving cycle and this option was selected for these tests.

Constant speeds: The vehicles were also tested over three different constant speed conditions at 50,
90 and 120 km/h (see Figure 4). The vehicle was driven at each speed for ten minutes but the
emissions were measured only during the second five minutes to ensure that the engine and engine
temperatures had stabilised.
New European Driving Cycle (NEDC)
140
Extra Urban Driving Cycle
(EUDC)
120
100
SPEED (km/h)
Figure 2
Urban Driving Cycle
(UDC)
80
60
40
20
0
0
200
400
600
TIME (s)
800
1000
1200
Figure 3
US06 SFTP Driving Cycle
140
Emission measurement
cycle
Conditioning cycle
120
SPEED (km/h)
100
80
60
40
20
0
0
200
400
600
800
1000
1200
TIME (s)
Figure 4
Constant Speed Tests
140
Emission measurement
120
SPEED (km/h)
100
Emission measurement
80
60
Emission measurement
40
20
0
0
200
400
600
800
1000
1200
1400
1600
1800
2000
TIME (s)
5.6.
Test fuels
The test fuels were specially blended by CONCAWE from refinery-typical blending components and
consisted of six fuels (see Figures 5a-5c). A summary of the key fuel properties is given in Table 2 and
more detailed fuel properties and distillation curves are provided in Appendix 1. The key variables for this
study were the Research Octane Number (RON), oxygen content, and oxygenate type. The Lower Heating
Value (calorific content) depended on the fuel composition.
Two hydrocarbon-only fuels were prepared with RONs of about 95 and 98 (Fuels 1 and 5). Three
oxygenated fuel blends (Fuels 3, 4, and 6) were prepared by blending oxygenate (either ethanol or ETBE)
into hydrocarbon-only base fuel (1) without any further adjustment in the fuel composition. This approach
is commonly called ‘splash blending’. One additional oxygenated fuel blend (Fuel 2) was prepared with
10% v/v ethanol (E10) and the hydrocarbon portion was also adjusted in order to ‘match’ the RON of Fuel
1.
Figure 5a
RON versus oxygen content (in % mass) for all test fuels
Figure 5b
RON versus Lower Heating Value (in MJ/kg) for all test fuels
Figure 5c
Table 2
Oxygen content (in % mass) versus Lower Heating Value (in MJ/kg) for all test fuels
Selected properties of the six test fuels
FUEL PROPERTIES
Units
Density @ 15oC
Vapour Pressure (DVPE)
Research Octane Number (RON)
Motor Octane Number (MON)
E70
E100
Sulphur
Oxygenates
Ethanol
kg/m³
kPa
% v/v
% v/v
mg/kg
% v/v
%vol
Fuel 1
Base
Fuel
735.9
57.2
95.0
85.7
29.0
57.7
<10
0.0
==
Fuel 2
E10
Match
745.0
60.0
95.4
85.7
43.4
55.8
<10
9.3
9.28
Fuel 3
15%
ETBE
734.1
63.2
97.1
87.1
31.6
65.6
10
14.4
==
Fuel 4
E10
Splash
740.4
64.4
98.5
86.6
47.7
61.4
<10
10.0
9.97
Fuel 5
High
Octane
742.3
59.7
98.0
86.3
30.1
55.8
<10
0.0
==
Fuel 6
E5
Splash
737.9
64.3
96.9
86.6
37.3
58.8
<10
5.0
5.01
Carbon
Hydrogen
Oxygen
H/C
% mass
% mass
% mass
-
86.3
13.7
==
1.89
83.3
13.3
3.4
1.90
84.0
13.7
2.3
1.94
82.9
13.5
3.6
1.94
86.8
13.2
==
1.81
84.7
13.5
1.8
1.90
Lower Heating Value (LHV)
Lower Heating Value (LHV)
MJ/kg
MJ/litre
43.52
32.03
41.94
31.25
42.59
31.27
41.93
31.04
43.49
32.28
42.72
31.52
6. PROGRAMME STRUCTURE
6.1.
Test protocol
The test programme was designed and analysed using statistical methods similar to those used in earlier
CONCAWE gasoline vehicle emission studies [5,6].
Each of the six fuels was tested on five separate occasions in each vehicle. Based on the variability levels
seen in earlier programmes, it was anticipated that this degree of replication would render differences in
fleet-average fuel consumption of (approximately) 1.7% statistically significant at P < 5%1.
The 30 tests on each car were conducted in five blocks of six, with one block consisting of one single test on
each fuel. The fuel test order within each block was randomized. This minimized the risk that fuel effects
would be influenced by any drift in vehicle performance or other time-related effects.
The test order is shown in Table 3 which was constructed so that:


Repeat tests on one test fuel were not conducted back-to-back ensuring that the results were truly
independent.
Each fuel was tested once on each day of the week. It was particularly important to test each of the
six fuels just once on Mondays. This is because vehicles tested on Mondays had a longer soak
period over the previous weekend compared to tests run on other days of the week.
Because the fuel was changed after every test, sufficient and appropriate vehicle conditioning was carried
out to ensure that the vehicle was properly adapted to the new fuel with no carryover between successive
tests (see Section 6.2 and Appendix 2).
Table 3
Fuel Testing Order
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Monday
6
3
5
4
2
1
Tuesday
3
6
2
5
1
4
Wednesday
5
2
6
1
4
3
Thursday
1
4
3
2
5
6
Friday
4
5
1
6
3
2
The protocol required an additional test to be conducted whenever large variations were seen between the
five tests on a particular fuel in a particular vehicle. The thresholds in Table 4 were used, based on the
variability levels seen in the earlier CONCAWE programme [5,6]. When the differences exceeded these
limits, an additional test was to be run at the completion of the initially planned series of tests. In the end,
extra tests were only conducted for one vehicle. This included one repeat of a voided test.
Table 4
Acceptance criteria where five blocks of tests are run
Ratio of highest to
lowest emission on the
same fuel
1
Fuel
Consumption
CO2
CO
THC
NOx
1.06
1.08
1.72
1.47
2.00
P<5% = the probability that such a difference could be observed by chance when no real effect exists is less than 5%. In other words,
we are 95% confident that the difference is real.
6.2.
Daily testing schedule
For each emissions test, it was considered important that the vehicle was presented and prepared in
exactly the same way so that a true comparison of fuel effects could be measured. The sequence of events
was:
1.
2.
3.
4.
Change test fuel
Condition vehicle/engine on test fuel
Cold soak vehicle
Run fuel economy and emissions tests
All of these steps had to be performed in a controlled and repeatable manner. Details on the fuel change
procedure are given in Appendix 2.
6.3.
Statistical data analysis
The average emissions for each vehicle and fuel are presented as bar charts in Section 7. Most of these
charts show simple arithmetic means from the five repeat tests on each fuel. One exception is PN (Figure
A4.2) where geometric means are plotted on logarithmic axes. Repeat PN test results can differ by more
than an order of magnitude so geometric means are used to mitigate the disproportionate influence of
higher valued test results.
The various means were calculated after the removal of a number of test results which were deemed to be
either invalid, or statistical ‘outliers’ with studentized residuals 2 significantly different from zero at P < 1%.
Corrected means are shown for those vehicles and emissions where there was a significant time trend at P
< 1%. All of the uncorrected and corrected means are tabulated in Appendix 6.
The error bars in the various bar charts in Section 7 show the mean value +/- 1.4 times the standard error
of the mean3 while those in the plots in Figures 11 and A3.2 to A3.5 show the mean value +/- 2.0 times the
standard error of the mean4.
2
Residuals divided by their standard errors
The factor 1.4 was chosen for consistency with previous CONCAWE reports [5,6,7]. The rationale was that, when two fuels are
significantly different from one another at P < 5%, then their error bars will not overlap; this factor also gives 84% confidence that the
true mean will lie within the limits shown. Error bars based on a factor of 1.4 were considered to be marginally too narrow for
determining significant differences in this study where a different number of tests was carried out. Such an interpretation would require
error bars based on factors in the region of 1.45 to 1.50, depending on the exact number of valid tests and whether or not a trend
correction has been applied.
4
The factor 2.0 gives approximately 95% confidence limits for the true mean. These are more appropriate for plots where the interest is
to demonstrate that the best fit line passes through each data point within the limits of experimental error.
3
7. TEST RESULTS
7.1.
CO2 emissions, fuel consumption, and energy
The measured CO2 emissions averaged over the repeat tests are shown in Figure 8 for all vehicles, fuels
and driving cycles. The error bars in all bar charts in this section show the mean value +/- 1.4 times the
standard error of the mean for the reasons described in Section 6.3.
The measured CO2 emissions in these tests varied according to the test driving conditions. At a given
driving condition, the differences in CO2 emissions between fuels were much smaller than the differences
between different vehicles.
At the same vehicle efficiency, we would expect emissions of CO2 at the tailpipe to decrease slightly for the
oxygenated fuels (Fuels 3, 4, 2 and 6 in descending order of oxygenate content), because of their slightly
lower C/H ratios. C/H ratios will also vary depending on the level of aromatics in the fuel. In practice, the
theoretical gCO2 per MJ of fuel varied by less than 1% as shown in Table 5:
Table 5
Differences between theoretical CO2 emissions on the six test fuels
gCO2/MJ
Change %
Fuel 1
72.71
Baseline
Fuel 2
72.83
0.16
Fuel 3
72.32
-0.54
Fuel 4
72.49
-0.30
Fuel 5
73.18
0.65
Fuel 6
72.70
-0.02
These differences are obviously quite small and the measured results showed no consistent differences
between the six test fuels.
Figure 8
Average CO2 emissions (g/km) for all vehicles, fuels, and driving cycles
200
180
CO2 (g/km)
160
140
Fuel 1
Fuel 2
Fuel 3
120
Fuel 4
Fuel 5
100
Fuel 6
80
NEDC
US06
50kph
90kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
60
120kph
The average volumetric fuel consumption (in l/100km) was then calculated from the measured CO2, HC
and CO emissions using the actual carbon content and the density of each test fuel, as described in Section
5.2 (see Figure 9).
Figure 9
Average volumetric fuel consumption (in l/100km) for all vehicles, fuels, and driving
cycles
9
8
FC (l/100 km)
7
Fuel 1
6
Fuel 2
Fuel 3
Fuel 4
5
Fuel 5
Fuel 6
4
NEDC
Figure 10
US06
50kph
90kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
3
120kph
Calculated average energy consumption (in MJ/km) for all vehicles, fuels, and driving
cycles
2.8
2.6
2.4
EC (MJ/km)
2.2
Fuel 1
2
Fuel 2
1.8
Fuel 3
Fuel 4
1.6
Fuel 5
Fuel 6
1.4
1.2
NEDC
US06
50kph
90kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
1
120kph
The energy consumption (in MJ/km) (Figure 10) was then derived using the measured LHV for each fuel.
As shown in Figure 10, the energy consumption (in MJ/km) varied primarily according to the test driving
conditions while there were smaller differences between the three vehicles. There were no consistent
differences between the six test fuels, suggesting that there was no difference in engine efficiency when
operating on the different fuels. This is analysed in more detail below.
The volumetric fuel consumption measured in litres/100km did show small differences between the six
test fuels, with the two pure hydrocarbon fuels (Fuels 1 and 5) giving lower volumetric fuel consumption.
An analysis of the fuel consumption (FC) was then completed for all driving cycles and the results for the
NEDC are shown in Figure 11.
Figure 11:
Average fuel consumption over the NEDC (in l/100km) versus the fuel’s Volumetric
LHV (left-hand plots) and the percentage change in FC versus the percentage change in
1/VLHV (right-hand plots)
Vehicle 1
Vehicle 1
5
7.3
E10 Splash
15% ETBE
7.1
E5 Splash
Base Fuel
E10 Match
6.9
High Octane
% change in FC
Fuel Consumption
7.5
6.7
4
3
15% ETBE E10 Splash
2
E5 Splash
1
E10 Match
0
-1
High Octane
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
32.3
-2
-1
Vehicle 2
% change in FC
Fuel Consumption
7.3
7.1
6.9
6.7
31.1
31.3
31.5
31.7
1
2
3
4
3
4
3
4
Vehicle 2
7.5
30.9
0
% change in (1/VLHV)
Volumetric Lower Heating value
31.9
32.1
5
4
3
2
1
0
-1
-2
32.3
y = 0.72x
-2
-1
0
1
2
% change in (1/VLHV)
Volumetric Lower Heating Value
Vehicle 3
Vehicle 3
5
% change in FC
7.5
Fuel Consumption
y = 0.79x
Base Fuel
7.3
7.1
6.9
6.7
4
3
2
1
y = 0.93x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
Volumetric Lower Heating Value
32.3
-2
-1
0
1
2
% change in (1/VLHV)
The left-hand plots show the measured FC (in l/100km) for all three vehicles over the NEDC plotted against
the Volumetric Lower Heating Value (VLHV in MJ/l) of the test fuel. The error bars show approximate 95%
confidence limits for the true FC and the solid line is a best fit through the data points. The (negative)
correlation between the FC and VLHV is evident for all three vehicles, with the volumetric FC decreasing as
the energy content of the fuel increases.
In the right-hand plots, the percent change in FC is plotted versus the percent change in [1/VLHV] relative
to the base fuel (Fuel 1). The solid black line is a best fit through the data points and the origin defined by
the base fuel, with the slope of the line indicated. The dashed lines show 95% confidence limits around the
best fit line. Finally, the red line is a one-to-one correlation line.
In the right-hand plots, the percentage changes in FC versus 1/VLHV can be interpreted as follows (see
Appendix 3 for more information). If the black best fit line falls below the red one-to-one correlation line,
then theincrease in volumetric FC for oxygenated fuels is smaller than would be expected from the
reduction in energy content of the fuel blend alone. Similarly, if the best fit line falls above the red one-toone correlation line, then the increase in FC is larger than the change in energy content.
For Vehicle 2, the best fit line is significantly lower than the one-to-one line suggesting that the % FC
increase is smaller than expected for this vehicle and driving cycle. Although the best fit line for Vehicle 1 is
also below the one-to-one line, it is within the 95% confidence limits, so the reduction in the % FC increase
falls just short of statistical significance.
The results on all three vehicles show that the volumetric FC over the NEDC decreases linearly as the fuel’s
energy content increases. Higher octane values or the use of different oxygenates as blending components
do not in general provide a volumetric FC benefit, at least in the Euro 4 vehicles and NEDC used in this
study. Because the results for Vehicle 2 and, to a lesser extent Vehicle 1, lie just below the one-to-one
correlation line, the efficiency of these vehicles may be somewhat better over the NEDC. In general,
however, the engine management systems in these vehicles do not compensate for the lower energy
content of the fuel through better engine efficiency performance on different fuel blends.
It should also be noted that the volumetric FC is usually reported by vehicle manufacturers and researchers
because it is a regulatory value intended to provide consumers with an understandable indicator of a
vehicle's efficiency over a typical driving cycle. Tailpipe CO2 emissions are also used in European
legislation, but will be influenced by the actual C/H ratio of the fuel as well as the vehicle efficiency.
However the true CO2 impact of different fuel choices can only be evaluated through a Well-to-Wheels
study such as that carried out by the JEC Consortium [9].
As shown by the graphs in Appendix 3, similar trends in FC vs. VLHV were also found for the same vehicles
and fuels over the US06 SFTP and the three steady-state conditions. This indicates that the NEDC is not
unique and that similar relationships between volumetric fuel consumption and the fuel’s energy content
exist over the two cycles and three steady-state conditions tested for these three vehicles. The small
reduction in the expected increase in FC on oxygenated fuels seen in Vehicle 2 over the NEDC was not seen
in the US06 cycle or at the three steady state conditions.
7.2.
Exhaust emissions
Averages for the various regulated exhaust emissions measurements are shown in this section for all
vehicles, fuels and driving cycles. Tables of uncorrected and corrected means, based on the statistical data
analysis reported in Section 6.3, are provided in Appendix 6.
As described previously, the error bars in all the bar charts show the mean value +/- 1.4 times the standard
error of the mean for the reasons described in Section 6.3. The charts show the average emissions for NOx
(Figure 12), CO (Figure 13), and Total Hydrocarbons (THC, Figure 14), as well as the NEDC based limit
values for Euro 4 vehicles. The US06 driving cycle is part of a set of driving cycles used within the USA
regulation; hence no single limit values for US06 can be given in the figures.
Particle emissions were also measured but are not regulated on Euro 4 vehicles. For this reason, the results
are provided for information in Appendix 4 for particulate mass (PM) (Figure A4.1) and particle number
(PN) emissions (Figure A4.2). Tables of uncorrected and corrected means are again provided in Appendix
6. PM emissions were only measured over the NEDC and US06 cycles.
Regulated pollutant emissions varied with the driving conditions and also showed differences between the
three vehicles. For NOx and THC, Vehicle 1 emissions are higher compared to the other vehicles in all
cycles. The test program was not set up to analyse these specific differences between the vehicles; the
engine characteristics, calibrations and TWC efficiency will rather lead to such differences.
Differences between the six test fuels were much smaller although statistically significant differences were
seen in some cases (see Section 7.3).
Figure 12:
Average NOx emissions for all vehicles, fuels and driving cycles
0.25
NOx (g/km)
0.2
0.15
Fuel 1
Fuel 2
Fuel 3
0.1
Fuel 4
Euro 4 Limit
Fuel 5
Fuel 6
0.05
NEDC
Figure 13:
US06
50kph
90kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
0
120kph
Average CO emissions for all vehicles, fuels and driving cycles
5
4.5
4
3
Fuel 1
2.5
Fuel 2
Fuel 3
2
Fuel 4
Fuel 5
1.5
Fuel 6
Euro 4 Limit
1
0.5
NEDC
US06
50kph
90kph
120kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
0
Veh. 1
CO (g/km)
3.5
Figure 14:
Average THC emissions for all vehicles, fuels and driving cycles
Euro 4 Limit
0.1
0.09
0.08
THC (g/km)
0.07
0.06
Fuel 1
0.05
Fuel 2
Fuel 3
0.04
Fuel 4
Fuel 5
0.03
Fuel 6
0.02
0.01
NEDC
US06
50kph
90kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
0
120kph
In most cases with only a few exceptions, emissions measured over the NEDC were significantly higher
than over the other test conditions. This is clearly due to the cold start part of the NEDC while the tests are
carried out with a hot engine both in the case of the US06 cycle and of the constant speed tests. A hot
engine means also a hot catalyst which efficiently reduces pollutant emissions.
7.3.
Effects of fuel properties on exhaust emissions
The charts in Appendix 5 show the average NOx, CO, THC, and CO2 emissions for all vehicles, fuels and
driving cycles.
Other than the effects of fuel energy content on CO2 emissions and volumetric fuel consumption that have
already been discussed in Section 7.1, there were few consistent trends for the effect of fuel properties on
NOx, CO, and THC emissions. Although the emissions do depend on the vehicle and test cycle, the
differences between fuels for each vehicle were small and frequently not statistically significant.
It should be pointed out that bag emission values are reported here as tailpipe emissions, which are in
general very low and clearly influenced by the catalyst. The concentrations of regulated pollutants
collected in the bags, especially over the hot start cycles, was often in the range of a few ppm. Reliably
measuring these very low emissions is a challenge, usually with more variability in relative terms, making
it more difficult to identify potential effects due to the fuel. Because the test procedure measured each fuel
five times in a randomised testing order, these measurement effects were mitigated to some extent.
One conclusion that can be drawn from these results is that three-way catalysts (TWCs) work very
efficiently. Even if there are some effects of oxygenates in gasoline on engine-out regulated emissions as
has been shown by various literature studies, these effects can be difficult to detect when evaluating
tailpipe emissions from hot engines and aftertreatment systems. The impact of the driving cycle and engine
technology on regulated emissions appears to be much more important than the variation in fuel
properties that were tested here.
8. RESULTS AND CONCLUSIONS
8.1.
CO2 emissions and fuel consumption
A major objective of this study was to determine whether today’s gasoline vehicles can improve their
efficiency when running on oxygenate/gasoline fuel blends. If the vehicle efficiency does not change with
different fuels, then the volumetric FC will vary in direct relation to the energy content (LHV) of the
oxygenate/gasoline blend. Since oxygenated blending components have lower energy content compared to
hydrocarbons, the volumetric FC would be expected to increase for oxygenated blends as the energy
content (LHV) of the fuel blend decreases.
The results shown in Figure 11 demonstrate that the volumetric FC does indeed increase in direct
proportion to the decrease in the fuel’s energy content. Because the results for Vehicle 2 and, to a lesser
extent in Vehicle 1, lie just below the one-to-one correlation line, the efficiency of these vehicles may be
somewhat better on oxygenated fuels over the NEDC. Comparable data in Appendix 3 show that the same
effects are not observed for these two vehicles over the US06 SFTP or at the three constant speeds (50, 90,
and 120km/h). In other words, over most test conditions, the use of oxygenates or higher octane did not
provide a volumetric FC benefit and the three vehicles selected for this study were not able to compensate
for the lower energy content of oxygenated gasoline and achieve better engine efficiency.
At the same vehicle efficiency, we would expect the volumetric tailpipe CO2 emissions should decrease
slightly for oxygenated fuels, because of their slightly lower C/H ratios. C/H ratios can also vary somewhat
depending on the concentration of hydrocarbon-only molecules in the fuel. In this study, the theoretical
gCO2 per MJ of fuel varied by less than 1% over all test fuels and no clear discrimination in CO 2 emissions
between the fuels could be seen in the measured results when expressed on an energy content basis.
8.2.
Regulated pollutant emissions
Regarding the regulated pollutant emissions compared to the Euro 4 limits:

All three vehicles complied with the Euro 4 limits for NOx, CO, and THC over the NEDC on all six test
fuels.

Fuel properties were found to have little effect on regulated emissions over all driving cycles even
though the octane and oxygenate contents of the fuels were widely varied.

Some notable vehicle and cycle differences were observed however:
 While NOx emissions were very low for Vehicles 2 and 3 over all test cycles, NOx emissions were
much higher for Vehicle 1 over the NEDC and at the 120kph constant speed. NOx emissions were
also about four times higher for Vehicle 1 over the US06 cycle compared to the other two test
conditions.
 CO emissions were much higher for Vehicles 1 and 3 over the US06 compared to the other test
cycles.
 THC emissions were high from Vehicle 1, compared to the other two vehicles, over most operating
conditions, including the hot-start tests where the catalyst conversion efficiency was expected to be
very high.
8.3.
Particle emissions

The three vehicles tested in this study were Euro 4 compliant and were not required to meet any
particle emissions limits for PM or PN. Nonetheless, the effects of driving cycle and fuel properties on
particle emissions is of general interest and were measured in this study using the PMP protocol. PM
emissions were collected on filters only over the NEDC and US06 driving cycles because the PM
amounts were expected to be very low from these gasoline vehicles. Fuel properties had little effect on
unregulated PM and PN emissions. One exception was the PM emissions for Vehicle 1 over the US06 in
which the PM emissions decreased somewhat with higher octane and higher oxygen content.

PM emissions were found to be between 0.4 and 0.8 mg/km for all vehicles over the NEDC.

PM emissions from Vehicle 1 were about six times higher (about 3 to 4 mg/km) over the US06
compared to the NEDC while PM emissions were at much lower levels (0.4 to 0.8 mg/km) for Vehicles 2
and 3 over these two cycles.

Over the NEDC, PN emissions were about two orders of magnitude higher for Vehicle 2 compared to
Vehicles 1 and 3. A similar trend was observed over the other test cycles with the exception of the US06.
9. REFERENCES
1.
Prepared for the European Commission Directorate General for Energy (2000) A Technical
Study on Fuels Technology related to the Auto/Oil II Programme – Volume II – Alternative Fuels,
December 2000
2.
Directive 98/69/EC (1998) of the European Parliament and of the Council of 13 October
1998 relating to measures to be taken against air pollution by emissions from motor vehicles and
amending Council Directive 70/220/EEC
3.
Directive 2009/28/EC (2009) of the European Parliament and of the Council of 23 April
2009 on the promotion of the use of energy from renewable sources
4.
CONCAWE (1990). The effects of temperature and fuel volatility on vehicle evaporative
emissions, Report 90/51, Brussels: CONCAWE
5.
CONCAWE (2003). Fuel effects on emissions from modern gasoline vehicles: Part 1 - sulphur
effects, Report 5/03, Brussels: CONCAWE
6.
CONCAWE (2004). Fuel effects on emissions from modern gasoline vehicles: Part 2 –
aromatics, olefins and volatility effects, Report 2/04, Brussels: CONCAWE
7.
CONCAWE (2009). Comparison of particle emissions from advanced vehicles using DG TREN
and PMP measurement protocols, Report 2/09, Brussels: CONCAWE
8.
EPEFE (1995). European Programme on Emissions, Fuels, and Engine Technologies, EPEFE
Report on behalf of ACEA and EUROPIA
9.
JEC WTW Version 3c (2011). Well-to-Wheels Analysis of Future Automotive Fuels and
Powertrains in the European Context, Report EUR 24952 EN-2011
10.
CONCAWE (2013). Effect of ethanol in gasoline on fuel consumption: a literature assessment
through 2006, Report 13/13, Brussels: CONCAWE
APPENDIX 1
Table A1.1
FUEL PROPERTIES
Fuel Properties
Units
Test Method
kg/m³
EN ISO 3675
Fuel 1
Base
Fuel
735.9
kPa
kPa
-
EN ISO 13016
EN ISO 13016
EN ISO 5164
EN ISO 5163
63.2
57.2
95.0
85.7
66.1
60.0
95.4
85.7
69.4
63.2
97.1
87.1
70.7
64.4
98.5
86.6
65.8
59.7
98.0
86.3
70.5
64.3
96.9
86.6
°C
°C
°C
°C
°C
°C
°C
°C
°C
°C
°C
°C
°C
% vol
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
EN ISO 3405
37.8
51.6
55.9
62.8
71.2
80.7
92.0
102.9
113.1
124.6
146.8
161.1
188.8
0.6
39.3
49.2
52.3
57.4
62.1
67.1
86.1
106.0
117.9
132.7
154.2
166.2
187.4
1.2
34.5
47.9
53.4
61.1
68.7
76.9
85.4
94.5
105.2
119.9
144.8
162.8
193.0
1.0
38.4
48.0
50.8
55.6
60.0
64.5
73.4
97.9
109.9
122.1
143.5
158.7
188.0
0.5
36.0
49.2
54.0
62.2
71.2
81.8
94.4
106.2
116.4
128.7
155.1
168.8
187.9
1.0
36.9
47.5
49.9
54.8
60.9
74.1
89.1
101.4
112.0
124.3
146.4
161.1
188.8
1.0
% v/v
% v/v
% v/v
EN ISO 3405
EN ISO 3405
EN ISO 3405
29.0
57.7
91.5
775
43.4
55.8
87.7
906
31.6
65.6
91.5
853
47.7
61.4
92.2
978
30.1
55.8
89.4
808
37.3
58.8
91.3
904
COMPOSITION
Sulphur
Paraffins
Olefins
Total Naphthenes
Aromatics
Total Oxygenates
Ethanol
mg/kg
% v/v
% v/v
% v/v
% v/v
% v/v
%vol
EN ISO 20884
EN ISO 22854
EN ISO 22854
EN ISO 22854
EN ISO 22854
EN ISO 22854
EN 13132
<10
55.2
7.7
6.9
28.6
0.0
==
<10
47.1
7.5
8.2
25.6
9.3
9.28
10
47.3
6.9
5.8
23.7
14.4
==
<10
50.3
7.0
6.3
25.4
10.0
9.97
<10
46.1
9.4
9.4
30.7
0.0
==
<10
53.4
7.1
6.7
26.9
5.0
5.01
Carbon
Hydrogen
Oxygen
H/C
% mass
% mass
% mass
-
EN 13132
Calculated
86.3
13.7
==
1.89
83.3
13.3
3.4
1.90
84.0
13.7
2.3
1.94
82.9
13.5
3.6
1.94
86.8
13.2
==
1.81
84.7
13.5
1.8
1.90
Lower Heating Value (LHV)
Lower Heating Value (LHV)
MJ/kg
MJ/litre
DIN 51603
Calculated
43.52
32.03
41.94
31.25
42.59
31.27
41.93
31.04
43.49
32.28
42.72
31.52
FUEL PROPERTIES
o
Density @ 15 C
Air Saturated Vapour
Pressure (ASVP)
Vapour Pressure (DVPE)
Research Octane Number (RON)
Motor Octane Number (MON)
DISTILLATION
IBP
5% v/v
10% v/v
20% v/v
30% v/v
40% v/v
50% v/v
60% v/v
70% v/v
80% v/v
90% v/v
95% v/v
FBP
Residue
E70
E100
E150
VLI
Abbreviations that are specific to this table:
ASVP
DVPE
E70, E100, or E150
FBP
H/C
IBP
LHV
MON
RON
VLI
Fuel 2
E10
Match
745.0
Fuel 3
15%
ETBE
734.1
Fuel 4
E10
Splash
740.4
Fuel 5
High
Octane
742.3
Fuel 6
E5
Splash
737.9
Air Saturated Vapour Pressure
Dry Vapour Pressure Equivalent
% evaporated at 70oC, 100oC, or 150oC
Final Boiling Point
Hydrogen to Carbon molar ratio
Initial Boiling Point
Lower Heating Value
Motor Octane Number
Research Octane Number
Vapour Lock Index
Figure A1.2
Distillation Curves
Test Fuel Matrix
100%
90%
80%
Fraction Evaporated
70%
60%
1: Base Fuel
2: E10 Matched
50%
3: 15% ETBE
4: E10 Splash
40%
5: High Octane
6: E5 Splash
30%
20%
10%
0%
0
20
40
60
80
100
120
Distillation Temperature [°C]
140
160
180
200
APPENDIX 2
DETAILS OF THE ORIGINAL TEST PROTOCOL
In this appendix the original test protocol is reported for reference purposes. When deviations from this test
protocol for practical reasons were needed, these were discussed and agreed within the group.
The objective of this protocol is to define a sound and repeatable way of measuring the short-term direct effect of fuels on
regulated emissions and fuel consumption. Both hydrocarbon-only and oxygen-containing fuels will be tested in this study in
order to evaluate the impact of oxygenate, especially ethanol, on vehicle emissions and fuel consumption.




CO2 emissions should be measured for its own evaluation and for the calculation of fuel consumption from the carbonbalance equation.
Other direct measures of fuel consumption (e.g. mass flow meter) may also be included.
Regulated emissions should include exhaust HC, CO, THC, NMHC, CH4, and NOx using the methods prescribed by
regulation.
Measurement of particulate mass (PM) emissions may be required on some vehicles.
The test procedure and protocols are based on the well-established EPEFE methods, simplified and modified where appropriate
to the needs of this JEC Programme. In particular, the importance and potential impact of vehicle conditioning has been carefully
considered with respect to this specific test programme. When followed carefully by a qualified laboratory, these procedures will
ensure sound test data and allow statistically valid interpretation, so that the effects of fuel changes on the test vehicle can be
accurately assessed.
It should be noted that fuel effects on emissions can be complex. A key finding of the EPEFE study was that the same fuel change
can have different effects in different vehicles, so results obtained on a specific vehicle should not be generalised.
Experimental Design
1.1
Test Fuel Matrix
The ethanol used in this study for blending fuels must be anhydrous and should be checked for the presence of denaturants
because there is evidence that some denaturants can have a detrimental effect on engine operation and performance. It is
recommended, where possible, not to use denaturants or, if this is not allowed, to use denaturants with proven no-harm effects
(e.g. petrol, MTBE, or ETBE).
The test fuel matrix is designed to evaluate the impact of fuel properties on exhaust emissions from advanced gasoline light duty
vehicles. The matrix is intended to separate the effect of ethanol from the effect of octane:
1.
2.
3.
4.
5.
Base Fuel, 95 RON hydrocarbon-only fuel
E10 Fuel, containing 10% v/v ethanol, matched in VP and octane to Fuel 1
ETBE blend, 95 RON
E10 Fuel, containing 10% v/v ethanol but splash blended
Hydrocarbon-only fuel matching the octane of Fuel 4,
splash-blended fuel
Octane
6. E5, containing 5% v/v ethanol but splash-blended.
(RVP)
The rationale for the fuel matrix is as follows:

Fuels 1, 2, 4, and 5 independently vary oxygen content
form a 2x2 factorial design.
5

Fuel 3 tests an alternative oxygenate where ETBE is
place of ethanol. The 95 grade was chosen (subject to
source such fuel) as representing the main European
grade.
 Fuel 6 provides a check on the linearity of any effect
The main fuel properties to be measured are listed below:
the E10
4
used in
ability to
gasoline
6
seen.
1
3
Oxygen
Measurement
Density (kg/m³)
RON
MON
DVPE (kPa)
E70 (% v/v)
Test Method (as
specified in EN228)
and RON to
Fuel Property
2
E100 (% v/v)
E150 (% v/v)
FBP (°C)
Aromatics (% v/v)
Olefins (% v/v)
Sulphur (mg/kg)
Ethanol (% v/v)
ETBE (% v/v)
Carbon (% m/m)
Hydrogen (% m/m)
Oxygen (% m/m)
Oxygenates content (% v/v)
Oxygenates other than
ethanol/ETBE (% v/v)
Water (mg/kg)
LHV (MJ/kg)
In order to improve the accuracy of the measured values of the test fuel properties, it is recommended that the fuel analyses are
performed in more than one laboratory. If the measured values for a specific fuel property differ by more than the typical
repeatability of the test method, the analysis of that fuel property should be repeated.
All test fuels should be blended to meet all other requirements of EN 228.Annex 5 provides details designed to avoid problems
with handling fuels containing ethanol, while the following sections provide more general fuel handling instructions.
1.2
Fuel Quantities
The fuel should be supplied in 50-litre drums in order to minimise the loss of light components and to facilitate fuel handling (a
50-litre drum can be easily stored in a dedicated refrigerator before being used for testing).
Based on the test procedure described in this test protocol, about 35 litres of fuel will be needed for each test.
The number of kilometres required for the combination of the fuel adaptation procedure, the pre-test conditioning, the Type I
test, the Artemis cycle, and the steady-state test is between 150 and 200 km. Even with a big car having a fuel economy figure in
the range of 11 litres/100 km (e.g. BMW 7), 25 litres will be sufficient to complete all of the pre-conditioning and testing.
This means that one 50-litre drum will be used for each test and the remaining 10-15 litres can be used to complete the
conditioning of the fuel system in the next test with the same fuel.
Considering 3 tests per fuel and per vehicle, nine 50-litre drums will be needed to complete the minimum number of tests
envisaged by the protocol (3 test per fuel x 3 vehicles). If a fourth test is required for all the vehicles, a minimum number of 12
drums will be needed. This gives a total of 600 litres per fuel.
To be on the safe side, 1000 litres of each fuel should be blended. This will permit a maximum number of 6 tests per fuel and per
vehicle.
1.3
Gasoline Handling and Storage Procedure
This protocol describes the gasoline handling procedures to be used by the testing laboratory. Specific material compatibility,
corrosion, and permeability issues related to ethanol are summarized in Annex 5.
The testing laboratory should check the following items:



Fuel shipment is complete
Barrels are labelled
Barrels are free from damage and leaks.
If the fuel shipment is incomplete, not clearly labelled, or damaged, the fuel blender should be notified immediately. Under no
circumstances should fuel from damaged barrels be used for testing.
1.4
Fuel Storage
Barrels should be stored undercover to prevent exposure to direct sunlight and water contamination. Barrels should be stored in
a cold area (below 5C) for a minimum of 12 hours immediately before decanting the fuel in order to minimise fuel vapour loss.
This is the preferred fuel handling method, and can be performed by JRC as long as 50-litre drums are used.
If it is not possible to store the test fuel below 5C prior to decanting, the fuel must be stored under a nitrogen blanket and an
example of a suitable system is shown in Figure 1. Every effort must be made to minimise the loss of the gasoline light ends at all
times because this can have a significant impact on the emissions test results.
Figure 1 - Example of a Nitrogen Fuel Blanketing and Dispensing System for 10- and 25-Litre Volumes
1.5
1.6
Fuel Decanting
It is recommended that a barrel tap be fitted to each barrel to allow safe decanting of the test fuel, with minimum vapour loss.
Fuel must only be decanted if the barrel has been stored below 5C for a minimum of 12 hours.
If it is not possible to store the test fuel below 5C prior to decanting, the fuel must be stored under a nitrogen blanket. An
example of a suitable system is described in Figure 1. Every effort must be made to minimise the loss of the light ends of the
gasoline at all times as this may have a significant effect on the emissions test results.
The testing laboratory should complete a visual inspection of the decanted fuel to confirm that the fuel is free from
contamination and is clear and bright in appearance.
All containers should be clean before they are used.
1.7
Excess Fuel
Under no circumstances should excess fuel be returned to the barrel after testing.
1.8
Test Protocol
To ensure that sufficient and reliable data are obtained to determine fuel effects, it is important that:
1. true (long term) repeat tests are conducted
2. the order of the test fuels is randomised to avoid bias due to engine drift
3. sufficient and appropriate vehicle conditioning is performed to compensate for the continual changes in test fuels.
The number of long-term repeats has been determined to ensure the desired discrimination of fuel effects. The more repeats
that are included, the smaller will be the fuel differences that can be measured with statistical significance. Short-term (back-toback) repeats have been excluded to allow more long term repeats to be achieved. If the difference between two tests on the
same fuel is too large, additional tests must be run to verify the result, using the criteria shown below.
The testing order described in the schedules below represents a single test 'block'. Multiple blocks must be run to provide longterm repeat data.
Based on a statistical evaluation of the number of repeats needed to distinguish a 1.7% fuel consumption effect for the design
fuel parameters, 5 blocks of data will be run for the fuel matrix. Additional blocks may be added after evaluation of the data, if
necessary, and if agreed by the JEC Team.
The test order must be randomised to prevent bias due to vehicle drift or other time-related effects. The random order shown in
the table below is for illustration only. A separate random order must be used for each block of testing and each vehicle. Tables
of random test order are shown in Annex 4.
A recommended testing schedule for the six fuels is shown here 5:
Note: It is not possible to arrange the design so that each successive set of 6 tests includes the 6 fuels, without using a cyclical order such as:
12345
5
Monday
Tuesday
Wednesday
Thursday
Friday
Week 1
6
3
5
1
4
Week 2
3
6
2
4
5
Week 3
5
2
6
3
1
Week 4
4
5
1
2
6
Week 5
2
1
4
5
3
Week 6
1
4
3
6
2
Each fuel should be tested five times, once on each day of the week.
1.9
Repeat Test Criteria
On completion of the prescribed number of test blocks, the repeatability of the data on each fuel will be checked according to the
criteria shown below. The ratio of the highest emission and the lowest emission over all the test blocks is measured for each fuel
separately. Where this ratio exceeds the figure in the appropriate table, a further repeat test must be run. This may be run at the
end of the test series, or if it is evident earlier that a repeat will be needed, it may be inserted earlier in the sequence. If following
this procedure, the variability of the results is still large, the JEC Team will consider whether further repeats are desirable.
In general, if there is an equipment failure or the test is invalidated for any reason, the test should be repeated immediately. This
repeat should include the normal fuel change procedure and conditioning, even though the same fuel is being used. Otherwise,
individual tests that are identified as falling outside of the criteria given in the tables below, should be repeated at the end of the
test programme.
61234
56123
45612
34561
23456
This would not be satisfactory since the fuels would always be tested in the same order.
Criteria for evaluation where 3 blocks of tests are run
Ratio of highest to lowest
emission on the same fuel
Fuel
Consumption
CO2
CO
THC
NOx
1.05
1.07
1.59
1.39
1.81
Criteria for evaluation where 4 blocks of tests are run
Ratio of highest to lowest
emission on the same fuel
Fuel
Consumption
CO2
CO
THC
NOx
1.06
1.08
1.66
1.44
1.92
Criteria for evaluation where 5 blocks of tests are run
Ratio of highest to lowest
emission on the same fuel
Fuel
Consumption
CO2
CO
THC
NOx
1.06
1.08
1.72
1.47
2.00
The above criteria are based on the repeatability data from a previous CONCAWE vehicle testing programme.
In the above tables, if, at the end of the test programme, the ratio of any 2 test results on the same fuel (larger/smaller) is greater
than the criteria, then an additional emissions test should be carried out. If three pairs of results now meet the criteria, then no
further tests are needed. If this test fails, then an additional emissions test should be carried out.
1.10 Test Vehicles
The objective of this testing is to evaluate fuel effects on vehicles of current technology, so that the results can be related to the
existing vehicle parc. These will include a mixture of vehicle and engine technologies, as described below.
Test vehicles will be selected on the basis that they are certified to meet the Euro 4 emissions regulations and are less than 2
years old. The test vehicle selection will be agreed by the JEC Team according to the availability of the different vehicle
technologies.
Initial thoughts are that the fleet should include

A PFI engine that is insensitive to octane

A VVT vehicle to check the effect of throttling

A vehicle optimised for 98 RON in order to take advantage of a higher octane number and the cooling effect of ethanol.
1.11 Test Vehicle Preparation
3.
1.
The test vehicle shall be presented in good mechanical condition and preferably have completed at least 8000 km on the
fuel recommended by the manufacturer prior to testing. This must be done in order to ensure that the catalyst is
adequately aged and that the engine combustion chamber deposits have stabilised. This initial mileage accumulation
can be carried out on the road or on a mileage accumulation dynamometer. If the vehicle has been left stationary for
more than 5 days it should be driven at least 100 km immediately prior to commencing the test sequence. All driving
must be representative of road conditions. The vehicle’s battery should be in good condition so that the EMS does not
experience power failure during the programme. If the battery is disconnected while work is being performed on the
vehicle, it should be done only before Step 2.
JRC requests that the vehicles are supplied in the above condition, with the vehicle having completed at least 8000 km.
The vehicles must have run on a Euro 4 specification (EN228) gasoline containing a commercial detergent for all of this
driving period. The maximum vehicle age is limited to two years, and a corresponding maximum mileage should not
exceed 30,000 km.
2.
The engine oil, oil filter, and air filter should be changed. The oil must be aged by driving a minimum of 500 km on the
road or mileage accumulation dynamometer; this can be included in the 8000 km pre-test mileage accumulation as
described in 1, thus the vehicle can be supplied to JRC after completing 7500 km. The fuels used for the oil ageing should
contain a commercial detergent additive package. A suitable fuel will be supplied by CONCAWE. The engine oil should be
changed to a reference oil (to be decided) the grade of which should be as recommended by the vehicle manufacturer,
and appropriate for normal vehicle service. A sample of the reference oil must be kept for subsequent analysis.
Before commencing the test programme, the emissions performance of the test vehicle must be measured and
confirmed to meet the emissions limits for which the vehicle was certified and the published fuel consumption/CO 2
data. The vehicle supplier should provide appropriate and verifiable road-load data for the dynamometer setting. For
this purpose, the test procedure appropriate to the certification should be used which should be based on true, and not
simulated, road-load data. A fuel which is representative of a certified reference fuel should be used for this evaluation.
At least two repeat tests should be run to ensure that the vehicle is properly stabilised. The JEC Team will assess the
outcome of these tests before proceeding with the main programme.
Vehicles are to be prepared in strict accordance with the ECE15+EUDC test procedure with the following additional
requirements.
4.
The fuel tank must be modified to accept a drain valve to allow the tank to be completely emptied between test fuels.
Where it is not possible to fit a drain valve in the bottom of the fuel tank due to safety reasons, it is recommended that
the fuel pump/fuel tank sender module be modified to accept an additional pipe, located so as to allow the tank to be
drained by means of a separate suction pump or an equivalent procedure to ensure the fuel is completely drained.
Advice from the manufacturer is necessary; they should know whether using the vehicle own pump the tank is
completely drained. If a drain valve has to be fitted to the tank, this will be done by the manufacturer or by JRC. If this
modification is done by JRC, then it must be authorised by the manufacturer)
5.
The setting of the engine and of the vehicle's controls shall be those prescribed by the manufacturer and should be
checked and adjusted if necessary. Any changes should be recorded immediately prior to testing. No further
adjustments are permitted during the test programme. If downtimes of >30 days occur during the test programme, rechecking of the vehicle settings is required.
6.
The tyre pressures should be checked and set to the manufacturer’s recommendation for use on the road. For the test
programme on the dynamometer, the cold tyre pressures should be set to 3.5 bar. The pressure of the tyres should be
checked frequently.
7.
The variation in RVP within the main fuel matrix is sufficiently small so as not to significantly influence the operation of
the evaporative emissions control system. As such, the carbon canister/evaporative emissions system must remain
connected and functioning throughout the test programme. In order to reduce variability, the carbon canister will be
changed every time the fuel is changed to a new test fuel.
8.
The appropriate coast down characteristics for the vehicle should be obtained or determined. The curve prescribed by
current legislation can be used only if these data cannot be obtained through JEC contacts. In addition, dynamometer
road-load data should be set and adjusted to the corresponding inertia class of the vehicle. It is recommended that
periodic checks are carried out throughout the programme to ensure consistent dynamometer performance e.g. by
performing a vehicle coast-down (gear in neutral, clutch pedal raised). Variations in vehicle run down characteristics
(carried out at the same condition) must be corrected and recorded. However, every effort should be made to avoid
changes to dynamometer settings in the middle of a block of test fuels.
9.
The test equipment must be in accordance with the appropriate regulations. All calibrations shall be conducted prior to
the test programme according to the provisions of and the test laboratory's internal quality assurance system.
Recalibration should be avoided during the test programme and any necessary changes must be recorded.
10.
The calibration reports shall be filed at the test laboratory for a period of 6 months after the end of the test programme
and shall be available for inspection upon request.
Daily Test Schedule
1.12 Test Outline
The principles of the test design are explained in Annex 2. For each emissions test, it is important that the vehicle is presented
and prepared in exactly the same way so that a true comparison of fuel effects is obtained. The sequence of events is
1. Change test fuel
2. Condition vehicle/engine
3. Cold soak vehicle
4. Fuel economy and emissions tests
All of these steps must be performed in a controlled and repeatable manner. Note that for vehicles equipped with NOx storage
catalysts, the NEDC test cycle is augmented by steady state and idle tests.
Target: fuel consumption and regulated emissions are essential. Other measurements should be included if they can easily be
collected but the quality of the fuel consumption and regulated emissions should not be compromised.

Fuel consumption & regulated emissions (NOx, CO, THC, NMHC, CH4)

Unregulated emissions (e.g., aldehydes and ethanol if the analyzer is available)

PM mass emissions (where applicable)
1.13 Test Cycles
Target: half-day testing per vehicle.

Cold New European Driving Cycle (NEDC)

Real world Cycle. The US06 cycle will be used. The start conditions must be controlled in a repeatable manner, either
through strict timing between cycles or through control of lubricant temperature.

Steady state. A “steady test cycle” divided in maximum three different phases will be defined. This will be run as a single
continuous test procedure, ensuring consistent timing between the three phases. The start conditions will be controlled,
as for the start of the real world cycles. For example, the vehicle could be driven for 10 minutes at 50 km/hr, then for 10
minutes at 90 km/hr and finally for 10 minutes at 120 km/hr. Gas samples would be taken for a certain period of time
(e.g. the last 5 minutes) at each constant speed condition.
Detailed instructions are given in Annex 1.
1.14 Measurements

Fuel Consumption (calculated using the carbon balance equation and the appropriate CWF fuel) and CO2.

Regulated emissions – capability of FID to measure THC. The FID is calibrated with propane. In order to estimate the
possible error due to a different response of the FID to oxygenates, a “calibration” gas containing oxygenates compounds
could be used. The possible gas composition needs to be considered.

Modal data. There is concern that extracting the raw exhaust gas for the modal data recording could introduce errors
and possibly greater variability in the bag measurements. Although the correction made for this loss in exhaust gas may
still leave an error in the regulated measurement, the addition of greater variability is less obvious. It is a trade-off
between this potential downside and the additional emissions information recorded during the test that can be used for
diagnostic purposes. In order to minimize sources of variability in the fuel consumption measurements, modal data will
not be taken and auxiliary measurements (such as, lubricant temperature, etc.) that are routinely collected by the JRC
Lab will be used for diagnostic analysis.

EMS data should be recorded using generic or dedicated diagnostic tools, as made available.

Unregulated emissions:

PM Emissions: Due to the expected low mass emissions, only one filter (primary without secondary) will be used for
the whole cycle using the PMP procedure.

Aldehydes (acetaldehyde and formaldehyde): If possible, this will be done using Sepak cartridges that can be stored
in the fridge for some time before analysis.

VOC Speciation (including ethanol). This will be done if the analyser is available for this programme.
Test Data Reporting
1.15 Test Results
A test report should be submitted for each individual emissions test, using a format substantially similar to, and containing all
the information shown, the example shown in Annex 2. Raw exhaust emissions at tailpipe should be measured and reported on
CD-ROM.
1.16 Test Result Summary
A summary table should be provided in electronic form showing the emissions results for the whole programme. Results should
be presented for fuel consumption and CO2, the regulated pollutants HC, CO, NOx, THC, NMHC, and CH4, and unregulated
emissions and PM (where applicable).
ANNEX1
Procedure for Evaluating Instantaneous Fuel Effects on Emissions
A flow chart for the test procedure is shown in Figure A.
1.17 A1.1
Test Sequence Start
The testing laboratory must follow the pre-determined test order specified in the relevant setcion. In order to help minimise test
variability, all emissions tests for a given test vehicle must be conducted on the same dynamometer. Since drivers can have a
significant impact on the emissions test results, the testing laboratory is encouraged to use the same driver or nominated standin throughout the test programme. If possible, all conditioning should also be carried out on the same dynamometer with the
same driver. Every effort should be made to ensure the consistency of the testing and any anomalies must be recorded on the
test data log.
1.18 A1.2
Drain Fuel
Remove all fuel from the fuel tank by means of the low point drain fitted during the vehicle preparation or, preferably, using the
vehicles own fuel pump to minimise the remaining fuel. The manufacturer should advise on this point; a layout of the tank could
be helpful. It is vital that as much fuel as possible is removed at this stage to minimise the cross contamination of the various fuel
blends being tested. Alternative fuel handling procedures may be used, but should be discussed and agreed in advance. The
carbon canister should be changed each time the fuel is changed to a new test fuel.
1.19 A1.3
10-litre Fill
Fill the vehicle fuel tank with 10 litres of the new test fuel. Carry out the fuel fill as quickly as possible and ensure that the fuel
filler cap is replaced immediately to minimise evaporative losses.
1.20 A1.4
5 Minutes Idle
Start the engine and idle for 5 minutes to allow the new test fuel to flush the fuel injection system thoroughly.
1.21 A1.5
Drain Fuel
Remove all fuel from the fuel tank by the same means as in Step A1.2. It is vital that as much fuel as possible is removed at this
stage to minimise cross-contamination of the various fuel blends being tested. In order to minimise a possible carry-over effect,
the steps A1.3-A1.5 could be repeated twice.
1.22 A1.6
25-litre Fill
Fill the vehicle fuel tank with 25 litres of the new test fuel. If more fuel is used, the impact of the higher-temperature fuel return
on vapour generation within the tank will be reduced. The 25-litre fill must be used even if the vehicle fuel system is return-less.
Carry out the fuel fill as quickly as possible and ensure that the fuel filler cap is replaced immediately to minimise evaporative
losses.
1.23 A1.7
Is a Sulphur Purge Needed?
For emissions tests on fuels having ultralow and constant sulphur levels, sulphur purging is not required.
1.24 A1.8
Vehicle Adaptation to Fuel Change
The car should be driven at conditions that will allow the necessary adaptation to fuel change to occur. This will depend on the
vehicle, but one cycle of adaptation will typically include 5-10 minutes of stabilised cruise at 60 mph (100 kph), followed by idle
for 3 minutes. (Note that the driving must be smooth to allow the systems to stabilise). This procedure should be completed 2 to
3 times, preferably in the test lab. There should then be a key-off cycle (and wait for 20 minutes) to ensure that these
adaptations have been learnt and saved before the emissions test conditioning phase begins.
Adaptation may be monitored by using a scan tool connected to the OBD port. Parameters such as the “fuel trim” will indicate
that the adaptation is complete.
The EVAP programme showed that the vehicle pre-conditioning prescribed by the legislation (3 UDC+3 EUDC in total) is not
sufficient to thoroughly purge the canister after it has been loaded during a diurnal EVAP test. However, since the vehicle is
these tests will be kept at a constant temperature of about 20°C, fuel evaporation will be very limited and the canister should not
be significantly loaded unless the fuel vapour pressure is well above 70 kPa. Moreover, this protocol requires a fuel adaptation
procedure in which the vehicle is driven for about 30 minutes at 100 kph. This is should be sufficient to purge the canister.
1.25 A1.9
1 ECE15 + 2 EUDC Test Cycles to Condition
Carry out one ECE and two consecutive EUDC test cycles according to the emissions test procedure, but do not take exhaust gas
samples. These test cycles are to ensure that the vehicle is fully conditioned on the test fuel before starting the first emissions
test.
1.26 A1.10
Cold Soak
The vehicle must be soaked according to the ECE+EUDC test procedure ensuring that the soak period is restricted to 12-18
hours. If the vehicle is soaked for longer than this period (for example, on Mondays following a weekend period), the vehicle will
be tested and the data analysed separately to determine whether the variability is significantly different from that in which the
12-18 hour soak period has been used. The JEC Team will discuss these data and agree any necessary adjustments to the test
procedures and analyses.
1.27 A1.11
Soak and Test Conditions
The soak and test temperatures must be in the range 20-30°C. Every effort should be made to minimise the temperature
variation during the test programme to within a range of 3°C. Humidity levels should be kept constant as far as is practical.
1.28 A1.12
ECE15 (11sec) + EUDC Emissions Test
Record the engine coolant temperature and oil sump temperature immediately before starting the test. Carry out the NEDC
emissions test according to the legislated test procedure, according to the recommendations of the NEDC (start sampling on
crank and 11 second idle).
1.29 A1.13
Emissions Measurements
Collect one bag sample for the ECE and one bag sample for the EUDC test for regulated emissions (CO, HC, NOx and CO 2), plus
any other agreed measures, such as THC, NMHC, CH4, and PM (using the PMP procedure). Auxiliary measurements should also
be made to enable a diagnostic interpretation of engine conditions.
1.30 A1.14
Other Test Cycles
Conduct other real-world and steady-state tests as agreed by the JEC Team.
1.31 A1.15
Is The Fuel Matrix Complete?
Return to Step A1.2 and continue testing according to the appropriate test order until the test programme has been completed.
1.32 A1.16
Check to See If More Repeats Are Needed
Please refer to the Test Protocol to determine which test fuels meet the repeat test criteria. Those fuels that require further tests
must be highlighted beforehand and tested. Additional repeats must be carried out in a random order relative to the previous
testing order, i.e. no two fuels should be tested in the same order.
1.33 A1.17
Stop
When the testing is complete, the test results should be reported to the JEC Team according to the format set out in Annex2.
Figure A: Flow chart for testing Light Duty Gasoline Vehicles
1. TEST SEQUENCE START
2
DRAIN FUEL
3
10-LITRE FILL OF
NEW TEST FUEL
9. 1 ECE15 + 2 EUDC
CYCLES TO CONDITION
4
5 MIN IDLE
10. COLD SOAK
11. SOAK AND TEST CONDITIONS
5
DRAIN FUEL
6
25-LITRE FILL
8. VEHICLE ADAPTATION
12. 1 ECE (11s) + EUDC TEST
13. EMISSIONS MEASUREMENTS
14. OTHER TEST CYCLES
NO
NO
15. IS FUEL
MATRIX
COMPLETE?
YES
YES
16. CHECK
FOR MORE
REPEATS
NO
17. STOP
7. SULPHUR
PURGE
NEEDED?
ANNEX2
Test Report for Light Duty Vehicles (Example)
The data should be presented in a flat file format: For the summary results file, each test should occupy a single line (row) in the
spreadsheet with sufficient columns to fully define the test parameters and all the resulting data. An example of a test report is
below.
Different file formats may be appropriate for additional data such as speciated HC and aldehydes. Time- related data (e.g. modal
data and EMS data) may be most easily stored in one file per test. These file names must either be linked to the test number
given in the summary file or be listed separately within the summary file.
LIGHT DUTY EMISSIONS TEST REPORT
Sheet 1 of 2
DRIVE CYCLE:
ECE(11s)+EUDC
VEHICLE ID:
XY27
COMPANY:
ANOEM
MODEL:
EUROCAR
GASOLINE/DIESEL
DIESEL
ODOMETER (km):
8000
TEST No:
OEM-X1-EA5-1a
FUEL CODE:
ABnn
DATE:
DD/MM/YY
CARBON (MASS%):
0,87
DRIVER:
A DRIVER
OIL CODE:
RLxxx
DYNAMOMETER:
PC1
COOLANT TEMP(C):
22,00
INERTIA (kg):
Xxxx
OIL TEMP (C):
22,20
LOAD SETTINGS:
X1, x2, x3
HC
NOX
HC+NOX
THC
CO
NMHC
CH4
PM
CO2
Fuel Consumption
FUEL CON (l/100km)
(93/116/EEC)
ECE
Bag 1 (g)
EUDC
Bag 2 (g)
ECE+EUDC
Per Test (g)
ECE
g/km
EUDC
g/km
ECE+EUDC
g/km
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,000
0,0000
0,000
0,000
0,0000
0,000
0,000
0,0000
0,000
0,000
0,0000
0,000
0,000
0,0000
0,000
0,000
0,0000
0,000
0,000
0,000
0,000
0,000
LIGHT DUTY EMISSIONS TEST REPORT
Sheet 2 of 2
RAW DATA
ECE
EUDC
ECE+EUDC
PM LOADING (mg)
00,000
00,000
00,000
ABS PRESS (mbar)
0,0
DISTANCE (km)
0,000
0,0000
0,0000
0,0
CVS VOLUME (l)
0,0
0,0
0,0
CELL TEMP (C) (start of
test)
REL. HUMIDITY (%)
0,000
0,0000
GAS MTR. TEMP (C)
0,0
0,000
0,000
AMBIENT HC (ppm
PROPANE)
AMBIENT CO (ppm)
COMMENTS
TEST VALIDATION
TEST ENGINEER:
..........
DATE:
TECHNICIAN:
..........
DATE:
CELL CONDITIONS
0,0
ANNEX3
Planning Guideline (For Information Only)
Minimum Number of Tests Needed for Statistical Significance
(based on the test-to-test variability found in the CONCAWE gasoline emissions programme 2003)
Assumptions:

Volumetric fuel consumption (calculated from the Carbon Balance method) is the key measurement from the test
programme.

The standard deviation of volumetric fuel consumption is the same as that achieved in a previous CONCAWE gasoline
test programme:
o
Standard deviations as low 1.1% to 1.5% (Car A) and as high as 2.2% to 3.7% (Car C) were measured on
different vehicles in the two phases of this test programme.
o
A standard deviation of 1.5% is assumed to be representative of current vehicles and vehicle testing.

Comparisons will be made on an individual vehicle basis. The response of individual vehicles may not be sufficiently
consistent to combine the data.

Comparisons will be made between individual pairs of fuels, or for the E0, E5 and E10 splash blend fuel series.

The difference in fuel consumption between fuels is estimated based on the change in energy content:
o
A 3.5% difference is estimated from that energy content of E10 against E0.
o A 1.7% difference is estimated from that energy content of E5 against E0
Estimated Test Requirements

To achieve resolution of a 3.5% FC difference, 2 or 3 long-term repeat tests will be required.
 To achieve resolution of a 1.7% FC difference, at least 5 long-term repeat tests will be required.
If the actual fuel consumption difference is less that that anticipated, it may not be detected when using the minimum number of
tests.
ANNEX4
Tables of Random Test Order
A separate random test order must be used for each vehicle tested, and each block of tests on the same vehicle. Take random test
orders from the following tables. Each horizontal line shows the fuel order for a single block of tests. For each vehicle, start at the
top and work down until the list is exhausted. If extra blocks are needed, then start again at the top.
Table A4-1
ANNEX5
10 Blocks of Random Test Orders for the Full Matrix (Fuels F1-F6)
3
5
2
4
6
2
1
3
4
6
4
1
5
2
6
4
5
1
6
2
3
5
4
2
1
1
3
4
5
6
4
2
6
1
3
3
5
6
4
1
4
1
6
5
3
4
6
2
5
3
1
5
3
3
6
2
5
2
2
1
Materials Compatibility, Corrosion, and Permeability
Only the fuel distribution system is considered in this section, and not the fuel system components commonly used on vehicles.
With respect to the compatibility with materials typically used in fuel supply and distribution systems, ethanol is different from
fuel hydrocarbons in three important ways:
o
The presence of the polar hydroxyl (-OH) group,
o
The relative size of the ethanol molecule, and
o
The higher conductivity of ethanol (and of ethanol/gasoline blends).
Because of these differences, various components in the fuel distribution system may be less compatible with ethanol/gasoline
blends than they are with hydrocarbon-only fuels.
1.
Many fuel system elastomers that have excellent compatibility with hydrocarbon-only fuels are themselves characterized
by polar constituents. These constituents contribute to the stability of the elastomer through hydrogen-bonding and
other interactions. These interactions may be vulnerable to substitution by the hydroxyl group of the ethanol. For this
reason, some elastomers can lose their structural integrity over time due to the loss of stabilizing hydrogen bonding
interactions when the elastomer is exposed to ethanol/gasoline blends. Ethanol can also extract plasticizers in the
elastomers, reducing the flexibility and toughness of the elastomer products. Fuel system components such as seals,
gaskets and piping that are made from polymers and elastomers must be designed to retain their structural integrity,
strength and flexibility after extended exposure to ethanol/gasoline blends.
2.
Because ethanol is a smaller and more polar molecule than MTBE, ETBE, and other oxygenates, there is a lower energetic
barrier for ethanol diffusing into and through elastomeric materials. Over time, ethanol can accumulate in these
materials, causing them to swell and soften, leading to an overall weakening of the elastomeric structure.
3.
In comparison to hydrocarbons, ethanol has a high conductivity and contains an active oxygen functionality. This can
contribute to corrosion and wear problems of some metal components. Furthermore, the suspension of water within the
ethanol/gasoline blend may enhance rusting and/or galvanic corrosion. The tendency of ethanol to loosen varnish and
gum deposits can also have a significant impact. By loosening these deposits, ethanol may accelerate wear of metallic
components that are in regular contact with fuel by scouring internal surfaces with suspended particles. The use of
corrosion inhibitors can help mitigate this problem although the compatibility of these additives with ethanol/gasoline
blends must be thoroughly evaluated.
Tables 1 and 2 provide an overview of materials that are either recommended for use or should be avoided when handling
ethanol or ethanol/gasoline blends.
Table 2
Recommendations for Materials Considered for Use in Ethanol and Ethanol/Gasoline Blend Applications
Material
Recommended
Not Recommended
Metals
Carbon steel with post-weld
heat treatment of carbon steel
piping and internal lining of
carbon steel tanks6
Stainless steel
Bronze
Aluminium
Zinc and galvanized materials
Brass
Copper
Lead/tin coated steel
Aluminium (may be an issue for
E100)
Elastomers
Buna-N (hoses & gaskets)
Fluorel
Fluorosilicone
Neoprene (hoses & gaskets)
Polysulfide rubber
Viton
Buna-N (seals only)
Neoprene (seals only)
Urethane rubber
Acrylonitrile-butadiene hoses
Polybutene terephthalate
Polymers
Acetal
Polypropylene
Polyethylene
Teflon
Fibreglass-reinforced plastic
Polyurethane
Polymers containing alcohol
groups (such as alcohol based
pipe dope)
Nylon 66
Fibreglass-reinforced polyester
and epoxy resins
Shellac
Others
Paper
Leather
Cork
This list is not comprehensive and the quality of the material must be appropriate for the intended application. It is strongly
advised that the manufacturers of these products are consulted before ethanol or ethanol/gasoline blends are introduced.
6
During the past decade, there have been some reports of stress corrosion cracking of unlined carbon steel storage tanks and non-heat-treated piping in
contact with fuel ethanol. At the time of this writing, the American Petroleum Institute (API) is preparing a recommended practice related to ethanol
storage.
Table 3
Compatibility of Ethanol with Materials Commonly Used in Fuel Distribution Systems
Item
Recommended
Containment
system (around
tank and loading
racks)
Not Recommended
Clay liners. Ethanol may
dry out the liner and allow
cracks to develop
Tanks used for E5
Mild steel
Fibreglass-reinforced plastic
(newer types)
Tanks used for
E100
May require a tank constructed of
a special chemical resin
Pumps used for
E100
Carbon & ceramic seals
Teflon-impregnated packing
materials
Pipe sealants used
for E5 and E100
Teflon tape
Meters used for
E5
When first converting to
ethanol/gasoline blends, it is
advisable to recalibrate meters
after 10-14 days to ensure that the
fuel change has not caused any
meters to over-dispense
Meters used for
E100
Internal O-rings & seals should be
selected that are specifically
designed for use with ethanol
Fuel Filters for E5
It may be necessary to change the
fuel filter shortly after converting
to ethanol/gasoline blends. Once
the dispensed fuel is clear and
bright, the filter life should be
similar to those in regular gasoline
applications.
Hoses used for E5
No problems reported
Hoses used for
E100
Contact the manufacturer
Nozzles used for
E5
No problems reported
Some lining materials
commonly used to prevent
small leaks such as older
types of epoxy or
polyester resin-based
materials. If a tank is
relined, the manufacturer
should be contacted for
advice.
Alcohol based pipe
sealants
Ethanol can dissolve the
glue in filter elements that
are not specifically
designed for this service
Filters containing shellac
In this table:
 The term ‘E100’ refers to pure or denatured ethanol.
 The term ‘E5’ refers to blends of motor gasoline containing up to 5% v/v ethanol (EN228).
ANNEX6
Assessment of Fuel Matrix Options
The fuel matrix proposed for the CONCAWE FE/STF/20 ethanol programme will test 5 fuels (1, 2, 4, 5 and 6) plus a sixth fuel (3)
which contains ETBE. The aim is to measure the effects of oxygen (i.e. EtOH content), Octane and RVP by fitting multiple
regressions models of the form
y = a + b.Oxygen + c.Octane + d.RVP
to emission or fuel consumption measurements y. It is assumed that fuel (3) will be excluded from this modeling process.
The fuels proposed are tabulated below
FUEL
OXYGEN OCTANE
1
0
0
2
1
0
4
1
1
5
0
1
6
0.5
0.5
7
0
1
where 0 and 1 denote the low level and high level of each factor.
RVP
0
0
1
0
1
1
Fuels 1, 2, 4, 5 and 6 in the table above do not form an orthogonal set. Plotting the fuels in 2d and 3d below, we see that while the
levels of oxygen and octane form a nice orthogonal square with a centre point, oxygen and octane are not orthogonal to RVP.
Therefore, we considered adding an extra fuel (7) to the fuel matrix which like fuel (5) is low in oxygen and high in octane, but
unlike fuel (5) is high in RVP.
The table below compares the likely standard errors of the coefficients a, b, c and d in the model above for different fuel subsets
for a notional emission, assuming similar levels of variability in each case
Fuel set
12456
12457
12467
124567
Intercept
Oxygen
Octane
RVP
0.845
1.165
1.165
1.195
0.866
1.000
1.323
1.323
0.866
1.000
2.449
2.236
0.823
0.984
1.164
1.047
EtO H study - F uel matr i x
O XYGEN*R VP
O C TA NE*O XYGEN
1. 0
0. 5
0. 0
0. 0
0. 5
O C TA NE*R VP
1. 0
0. 0
0. 5
1. 0
1. 0
0. 5
0. 0
0. 0
0. 5
1. 0
F UEL
1
2
4
5
6
7
EtOH study - Fuel matrix
FUEL
1
2
4
5
6
7
1.0
O C T A NE
0.5
1.0
0.0
0.0
0.5
0.5
O XY GEN
1.0
RV P
0.0
The lowest SEs are of course observed when all six fuels are tested as there is more data. If resources constrain us to 5 fuels, then
replacing fuel (6) in the original matrix by fuel (7) is not helpful as fuel (6) helps disentangle Octane and RVP (see 2d
Octane*RVP plot). Replacing fuel (5) by fuel (7) makes the Octane and RVP correlation even worse.
The only realistic options, therefore, are to test the original 5 fuels (1, 2, 4, 5, 6) or the six fuels (1, 2, 4, 5, 6, 7), plus fuel (3) in
each case. The improvement in the SE of the effect of oxygen is 16% with a 12% improvement for RVP. This needs to be traded
off against the cost of testing the extra fuel – which could in turn mean testing 2 cars instead of 3.
The case for including fuel (7) in the matrix is not particularly compelling and it certainly should not be used in place of fuels (5)
or (6). Even though fuel (6) is a 50:50 mix of fuels (1) and (4), it is expected to be high in RVP and hence has been assigned a
nominal RVP value of 1.0 rather then 0.5. The high RVP is helpful for modeling purposes.
Recommendation:
No change to the fuel matrix. Test fuels (1, 2, 4, 5 and 6) plus fuel (3).
Prepared by P.J. ZEMROCH at the request of CONCAWE FE/STF-20.
APPENDIX 3
ADDITIONAL FUEL CONSUMPTION RESULTS
Figure A3.1 helps to explain the right-hand plots in Figures 11 and A3.2-A3.5. The plots in Figures A3.2 to
A3.5 show the average fuel consumption (FC) over the US06 SFTP and the three steady state cycles in the
same format as the plots in Figure 11 over the NEDC.
In each figure, the left-hand plots show the measured FC (in l/100km) for all three vehicles at the chosen
test condition plotted against the Volumetric Lower Heating Value (VLHV in MJ/l) of the test fuel. The error
bars show approximate 95% confidence limits for the true FC and the solid line is a best fit through the
data points. The (negative) correlation between the FC and VLHV is strong for all vehicles and test
conditions, with volumetric FC decreasing as the energy content of the fuel increases.
In the right-hand figures, the percent change in volumetric FC is plotted versus the percent change in
[1/VLHV] relative to the base fuel. The solid black line is a best fit through the data points and through the
origin defined by Fuel 1, with the slope of the line indicated. The dashed lines show 95% confidence limits
around the best fit line. Finally, the red line is a one-to-one correlation line.
In Figure A3.1, four different regimes separated by the red and blue lines can be identified by comparing
the black best fit line (or the data points) with the red one-to-one correlation line. The one-to-one line is
the expected FC change from the change in energy content.
Regime A: in this regime, the % change in FC is larger than expected based on the % change in energy
content of the fuel;
Regime B: the % change in FC is smaller than expected based on the % change in energy content of the fuel
Regime C: the % change in FC is larger than expected based on the % change in energy content of the fuel;
Regime D: the % change in FC is smaller than expected,.
Results in regimes B and C demonstrate better than expected FC performance which means that the
vehicle’s powertrain is taking advantage of the fuel properties and FC is less or more than expected. In
regime A FC is higher than expected and in regime D FC reductions are less than expected.
Figure A3.1 Picture showing the % change in FC versus the % change in 1/VLHV. The letters A–D
identify different % FC versus % 1/VLHV regimes.
In the following figures, the data in the left-hand plots show that the volumetric FC over the US06 cycle and
three steady-state speeds decreases as the fuel’s energy content increases. There is no evidence in the
right-hand plots to suggest that the use of oxygenates as gasoline blending components provides a FC
benefit when expressed on an energy content basis for any vehicle or test condition with all the one-to-one
lines falling within the 95% confidence limits. This is somewhat different from the NEDC results in Section
7.1 where a small benefit was seen in Vehicle 2 and, to a lesser extent, in Vehicle 1.
Figure A3.2 Average fuel consumption over the US06 (in l/100km) versus the fuel’s Volumetric
LHV and the percentage change in FC versus the percentage change in 1/VLHV
Vehicle 1
% Change in FC
Fuel Consumption
Vehicle 1
8.4
8.3
8.2
8.1
8.0
7.9
7.8
7.7
7.6
E10 Splash
15% ETBE
E5 Splash
E10 Match
Base Fuel
High Octane
30.9
31.1
31.3
31.5
31.7
31.9
32.1
5
4
3
2
1
0
-1
-2
32.3
Base Fuel
-2
-1
0
1
2
3
4
3
4
3
4
% change in (1/ VLHV)
Vehicle 2
Vehicle 2
5
8.4
8.3
8.2
8.1
8.0
7.9
7.8
7.7
7.6
% change in FC
Fuel Consumption
E10 Match
y = 1.11x
High Octane
Volumetric Lower Heating Value
4
3
2
1
y = 0.93x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
32.3
-2
-1
Volumetric Lower Heating Value
0
1
2
% change in (1/VLHV)
Vehicle 3
Vehicle 3
5
8.4
8.3
8.2
8.1
8.0
7.9
7.8
7.7
7.6
% change in FC
Fuel Consumption
E10 Splash
15% ETBE
E5 Splash
4
3
2
1
y = 0.83x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
Volumetric Lower Heating Value
32.3
-2
-1
0
1
2
% change in (1/VLHV)
Figure A3.3 Average fuel consumption at 50km/h (in l/100km) versus the fuel’s Volumetric LHV
and the percentage change in FC versus the percentage change in 1/VLHV
Fuel Consumption
4.2
E10 Splash
15% ETBE
4.1
E5 Splash
Base Fuel
4.0
E10 Match
3.9
High Octane
3.8
% change in FC
Vehicle 1
4.3
3.7
30.9
31.1
31.3
31.5
31.7
31.9
32.1
Vehicle 1
5
4
3
2
1
0
-1
-2
32.3
E10 Match
Base Fuel
-2
-1
Vehicle 2
1
2
3
4
3
4
3
4
Vehicle 2
5
4.2
% change in FC
Fuel Consumption
0
% change in (1/VLHV)
4.1
4.0
3.9
3.8
4
3
2
1
y = 1.00x
0
-1
3.7
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
32.3
-2
-1
0
1
2
% change in (1/VLHV)
Volumetric Lower Heating Value
Vehicle 3
Vehicle 3
4.3
5
4.2
4
% change in FC
Fuel Consumption
E5 Splash
y = 1.24x
High Octane
Volumetric Lower Heating Value
4.3
E10 Splash
15% ETBE
4.1
4.0
3.9
3.8
3.7
3
2
1
y = 1.06x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
Volumetric Lower Heating Value
32.3
-2
-1
0
1
2
% change in (1/VLHV)
Figure A3.4 Average fuel consumption at 90km/h (in l/100km) versus the fuel’s Volumetric LHV
and the percentage change in FC versus the percentage change in 1/VLHV
Vehicle 1
5.7
5.6
5.5
E10 Splash
5.4
15% ETBE
5.3
E5 Splash
E10 Match
Base Fuel
5.2
High Octane
5.1
30.9
31.1
31.3
31.5
31.7
Vehicle 1
5
% change in FC
Fuel Consumption
5.8
31.9
32.1
4
E10 Match
2
E5 Splash
1
High Octane
0
-1
-2
32.3
-2
-1
Vehicle 2
1
2
3
4
3
4
3
4
Vehicle 2
5
5.7
% change in FC
Fuel Consumption
0
% change in (1/VLHV)
5.6
5.5
5.4
5.3
5.2
5.1
4
3
2
1
y = 1.37x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
32.3
-2
-1
0
1
2
% change in (1/VLHV)
Volumetric Lower Heating Value
Vehicle 3
5.8
5
5.7
4
% change in FC
Fuel Consumption
y = 1.21x
Base Fuel
Volumetric Lower Heating Value
5.8
E10 Splash
15% ETBE
3
5.6
5.5
5.4
5.3
5.2
5.1
Vehicle 3
3
2
1
y = 1.14x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
Volumetric Lower Heating Value
32.3
-2
-1
0
1
2
% change in (1/VLHV)
Vehicle 1
8.3
8.2
8.1
8.0
7.9
7.8
7.7
7.6
7.5
E10 Splash
15% ETBE
E5 Splash
E10 Match
Base Fuel
High Octane
30.9
31.1
31.3
31.5
31.7
31.9
32.1
% change in FC
Fuel Consumption
Figure A3.5 Average fuel consumption at 120km/h (in l/100km) versus the fuel’s Volumetric LHV
and the percentage change in FC versus the percentage change in 1/VLHV
Vehicle 1
5
4
3
2
1
0
-1
-2
E10 Match
E5 Splash
Base Fuel
-1
1
2
3
4
3
4
3
4
Vehicle 2
5
% change in FC
Fuel Consumption
Vehicle 2
4
3
2
1
y = 1.19x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
32.3
-2
-1
Vehicle 3
1
2
Vehicle 3
5
% change in FC
8.3
8.2
8.1
8.0
7.9
7.8
7.7
7.6
7.5
0
% change in (1/VLHV)
Volumetric Lower Heating Value
Fuel Consumption
0
% change in (1/VLHV)
Volumetric Lower Heating Value
8.3
8.2
8.1
8.0
7.9
7.8
7.7
7.6
7.5
y = 1.06x
High Octane
-2
32.3
E10 Splash
15% ETBE
4
3
2
1
y = 1.07x
0
-1
-2
30.9
31.1
31.3
31.5
31.7
31.9
32.1
Volumetric Lower Heating Value
32.3
-2
-1
0
1
2
% change in (1/VLHV)
APPENDIX 4
PM AND PN UNREGULATED EMISSIONS
Regulatory limits for particulate mass (PM) and particle number (PN) emissions from gasoline vehicles
were only introduced with the Euro 5/6 regulation and therefore do not apply to the Euro 4 vehicles tested
in this study. Nevertheless these emissions were measured for the three vehicles tested in this programme
in order to obtain some preliminary information on potential driving cycle and fuel effects.
PM was measured only over the NEDC and US06 cycles and was not measured during the short sampling
period of the steady state tests because the PM mass was expected to be too low to be reliably measured.
Emissions were in fact measured at each constant speed only for five minutes, compared to the 10 or 20
minutes of the cycles. In addition, the measurement could be biased by artefacts due, for example, to water
condensation especially at high speed (120 kph) when the dilution ratio reaches its minimum value.
Figure A4.1 Average PM emissions for all vehicles, fuels and driving cycles
5
4.5
4
PM (mg/km)
3.5
3
Fuel 1
2.5
Fuel 2
Fuel 3
2
Fuel 4
Fuel 5
1.5
Fuel 6
1
0.5
NEDC
US06
50kph
90kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
0
120kph
The PN emitted by the vehicles was also measured following the PMP methodology. From previous
development work, it is known that the PMP-compliant particle counting systems measure only the
number of solid particles because the volatile particle remover (VPR) removes the volatile fraction before
counting.
Sampling was conducted according to the current legislation. The exhaust gas was primarily diluted and
conditioned following the Constant Volume Sampling (CVS) procedure. The CVS tunnel was equipped with
high efficiency filters and an activated carbon scrubber for particles and hydrocarbons that reduce particle
contributions from the dilution air to near zero levels (99.99% reduction of particles with size diameter of
0.3 μm). The temperature of the dilution air was conditioned to 23±1°C during all tests.
Figure A4.2 Average PN emissions (using geometric means) for all vehicles and driving cycles
NEDC
US06
50kph
90kph
120kph
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
PN (#/km; geometric means)
1E+13
1E+12
1E+11
Fuel 1
Fuel 2
1E+10
Fuel 3
Fuel 4
Fuel 5
Fuel 6
1E+09
Background
1E+08
Veh. 1
Fuel1
Fuel 2
Veh. 1
Fuel 3
Fuel 4
Veh. 1
Fuel 5
Fuel 6
0
Fuel1
Fuel 2
Fuel 3
Fuel 4
Veh. 2
Fuel 4
Fuel 5
Fuel 5
Fuel 6
Veh. 3
Fuel 5
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 1
Veh. 3
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Fuel 5
Veh. 3
Fuel 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Fuel 5
Veh. 2
Veh. 3
Fuel 4
Veh. 1
NOx (g/km) - 120 km/h
Fuel 4
Veh. 3
0.05
Fuel 2
Fuel 4
Veh. 2
0.06
Fuel 3
Veh. 1
Fuel1
Fuel 3
Veh. 3
Fuel 6
Fuel 3
Veh. 2
0
Veh. 1
NOx (g/km) - 90 km/h
Veh. 1
0.02
Fuel 2
Veh. 3
0.05
Fuel 2
Veh. 2
NOx (g/km) - 50 km/h
Veh. 1
Fuel1
Veh. 3
NOx (g/km) - US06
Veh. 2
0.06
Fuel 2
Veh. 2
Fuel 6
Veh. 3
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
CO (g/km)
NOx (g/km) - NEDC
Veh. 1
0
Veh. 2
0.02
Veh. 3
0.05
Veh. 2
0.06
Veh. 3
Fuel1
Veh. 3
Fuel 6
Veh. 1
Fuel1
Veh. 2
Note the change in y-axis scale compared to the other charts on NOx
Veh. 3
0
Veh. 1
0.05
Veh. 3
0.2
Veh. 1
0.25
Veh. 1
Fuel 6
Veh. 3
0.02
Veh. 1
Veh. 2
Veh. 3
0
Veh. 2
0.1
CO (g/km)
0.15
Veh. 1
Veh. 2
Veh. 3
Veh. 3
Veh. 1
0.01
Veh. 2
Veh. 3
Veh. 1
Veh. 1
Veh. 2
0.03
Veh. 1
Veh. 1
Veh. 2
Veh. 2
Veh. 3
0.04
Veh. 2
0.03
CO (g/km)
Veh. 2
Veh. 3
Veh. 3
Veh. 1
0.05
Veh. 2
0.03
CO (g/km)
Veh. 2
Veh. 3
Veh. 3
Veh. 1
Veh. 1
Veh. 2
NOx (g/km)
0.06
Veh. 1
0.03
CO (g/km)
Fuel 5
Veh. 2
Fuel 5
Veh. 3
Veh. 3
Veh. 1
Fuel 5
Veh. 2
Veh. 3
Veh. 1
Veh. 1
Veh. 2
Veh. 1
Veh. 2
Fuel 5
Veh. 3
Fuel 4
Veh. 3
Fuel 4
Veh. 1
Veh. 1
Fuel 4
Veh. 2
Veh. 2
Veh. 3
Veh. 2
Veh. 3
Fuel 4
Veh. 2
Fuel 3
Veh. 2
Fuel 3
Veh. 3
Veh. 3
Veh. 1
Fuel 3
Veh. 2
Veh. 3
Veh. 1
Veh. 1
Veh. 2
Veh. 3
Veh. 1
Fuel 3
Veh. 3
Fuel 2
Veh. 3
Veh. 1
Fuel 2
Veh. 2
Veh. 2
Veh. 3
Fuel 2
Veh. 1
Fuel1
Veh. 2
Fuel1
Veh. 3
Veh. 3
Veh. 1
Veh. 1
Veh. 2
NOx (g/km)
Fuel 2
Veh. 2
Veh. 3
Veh. 1
Veh. 1
Veh. 2
NOx (g/km)
Fuel1
Veh. 3
Veh. 1
Veh. 2
NOx (g/km)
Fuel1
Veh. 2
Veh. 1
Veh. 3
Veh. 2
NOx (g/km)
APPENDIX 5
AVERAGE FUEL EFFECTS ON REGULATED EMISSIONS
A5.1 NOx (left) and CO (right) emissions for all driving cycles and vehicles
1
CO (g/km) - NEDC
0.9
0.8
0.7
0.6
0.02
0.5
0.4
0.3
0.2
0.1
0
Fuel 6
4.5
5
CO (g/km) - US06
3.5
4
2.5
3
1.5
2
0.5
1
0
Note the change in y-axis scale compared to the other charts on CO
Fuel 6
0.9
1
CO (g/km) - 50 km/h
0.04
0.8
0.7
0.6
0.5
0.4
0.01
0.3
0.2
0.1
0
Fuel 6
0.9
1
CO (g/km) - 90 km/h
0.04
0.8
0.7
0.6
0.5
0.4
0.01
0.3
0.2
0.1
0
Fuel 6
0.9
1
CO (g/km) - 120 km/h
0.04
0.8
0.7
0.6
0.5
0.4
0.01
0.3
0.2
0.1
0
Fuel1
Fuel 2
Fuel 3
Fuel 4
Fuel 5
Fuel 6
0.005
0
Fuel1
Fuel 2
Fuel 3
Fuel 4
Veh. 3
Fuel 4
Fuel 5
Fuel 5
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Fuel 5
Fuel 6
Veh. 3
0.02
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Fuel 5
Veh. 2
THC (g/km) - 120 km/h
Fuel 3
Veh. 3
Veh. 2
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Fuel 5
Veh. 1
0.025
Fuel 2
Fuel 4
Veh. 3
Fuel1
Fuel 4
Veh. 2
Fuel 6
Fuel 4
Veh. 1
0.005
Fuel 3
Veh. 3
THC (g/km) - 90 km/h
Veh. 1
0.01
Fuel 3
Veh. 2
0.02
Fuel 3
Veh. 2
0.025
Fuel 2
Veh. 1
Fuel1
Veh. 2
0.01
Fuel 2
Veh. 2
THC (g/km) - 50 km/h
Veh. 1
THC (g/km) - US06
Veh. 3
0.02
Fuel 2
Veh. 3
0.025
Veh. 1
Veh. 3
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
CO2 (g/km)
THC (g/km) - NEDC
Veh. 2
0.01
Fuel1
Veh. 3
Note the change in y-axis scale compared to the other charts on THC
Veh. 3
0
Veh. 1
0.01
Veh. 1
0.02
Veh. 3
0.04
Veh. 1
188
Veh. 2
0.07
Veh. 2
0.08
Veh. 1
190
Veh. 1
Fuel1
Veh. 2
Fuel 6
Veh. 2
0.1
0.09
Veh. 2
Veh. 1
Veh. 2
0.04
Veh. 3
Veh. 2
Veh. 3
0.05
Veh. 3
Veh. 3
Veh. 1
164
Veh. 2
0.05
CO2 (g/km)
Veh. 1
Veh. 2
166
0.07
Veh. 3
Fuel 6
Veh. 1
Veh. 3
Veh. 2
150
Veh. 2
0.08
Veh. 1
0
Veh. 1
Veh. 3
Veh. 1
152
0
Veh. 3
168
Veh. 2
Fuel 6
Veh. 1
0.015
CO2 (g/km)
Veh. 1
Veh. 2
154
0.01
Veh. 3
170
Veh. 3
0.015
CO2 (g/km)
Veh. 2
Veh. 3
156
0.02
Veh. 1
0.1
0.09
Veh. 2
0.015
CO2 (g/km)
Veh. 3
Veh. 2
Veh. 3
Veh. 1
Veh. 1
0.03
Veh. 2
THC (g/km)
0.06
Veh. 1
Veh. 3
Fuel 5
Veh. 2
Fuel 5
Veh. 3
Veh. 3
Veh. 1
Fuel 5
Veh. 2
Veh. 3
Veh. 1
Veh. 1
Veh. 2
Veh. 1
Veh. 2
Fuel 5
Veh. 1
Veh. 3
Fuel 4
Veh. 2
Fuel 4
Veh. 1
Fuel 4
Veh. 2
Veh. 2
Veh. 3
Veh. 2
Veh. 3
Fuel 4
Veh. 1
Fuel 3
Veh. 2
Fuel 3
Veh. 3
Veh. 3
Veh. 1
Fuel 3
Veh. 3
Veh. 3
Veh. 1
Veh. 1
Veh. 2
Veh. 3
Veh. 1
Fuel 3
Veh. 2
Fuel 2
Veh. 1
Veh. 1
Fuel 2
Veh. 2
Veh. 2
Veh. 3
Fuel 2
Veh. 3
Veh. 2
Fuel1
Veh. 3
Veh. 3
Veh. 1
Veh. 1
Veh. 2
THC (g/km)
Fuel 2
Veh. 2
Veh. 3
Veh. 1
Veh. 1
Veh. 2
THC (g/km)
Fuel1
Veh. 1
Veh. 1
Veh. 2
THC (g/km)
Fuel1
Veh. 3
Fuel1
Veh. 2
Veh. 1
Veh. 3
Veh. 2
Veh. 1
THC (g/km)
A5.2 HC (left) and CO2 (right) emissions for all driving cycles and vehicles
CO2 (g/km) - NEDC
162
160
158
Note the change in y-axis scale compared to the other charts on THC
Fuel 6
CO2 (g/km) - US06
0.06
186
184
182
0.03
180
178
176
174
172
170
Fuel 6
100
98
CO2 (g/km) - 50 km/h
96
94
92
90
0.005
88
86
0
84
82
80
Fuel 6
135
133
CO2 (g/km) - 90 km/h
131
129
127
125
123
121
119
117
115
Fuel 6
190
188
CO2 (g/km) - 120 km/h
186
184
182
180
178
176
174
172
170
APPENDIX 6
AVERAGE EMISSIONS (UNCORRECTED AND CORRECTED FOR TIME TRENDS)
A6.1 Regulated emissions
CYCLE
VEHICLE
FUEL
FUEL NAME
THC (g/km)
Unc orrec t ed
NEDC
US06
50 km/h
90 km/h
120 km/h
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
0.0813
0.0694
0.0726
0.0722
0.0777
0.0756
0.0320
0.0298
0.0378
0.0295
0.0317
0.0276
0.0340
0.0251
0.0336
0.0286
0.0357
0.0343
0.0800
0.0819
0.0749
0.0716
0.0764
0.0752
0.0027
0.0028
0.0032
0.0028
0.0027
0.0030
0.0081
0.0068
0.0087
0.0067
0.0074
0.0072
0.0086
0.0091
0.0098
0.0085
0.0086
0.0085
0.0005
0.0003
0.0005
0.0002
0.0004
0.0006
0.0006
0.0009
0.0009
0.0007
0.0007
0.0008
0.0199
0.0170
0.0231
0.0200
0.0170
0.0208
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0003
0.0003
0.0003
0.0002
0.0003
0.0003
0.0156
0.0150
0.0161
0.0156
0.0151
0.0156
0.0046
0.0047
0.0052
0.0051
0.0041
0.0050
0.0065
0.0075
0.0078
0.0068
0.0069
0.0069
Correc t ed
0.0028
0.0029
0.0031
0.0028
0.0027
0.0028
0.0203
0.0177
0.0229
0.0201
0.0163
0.0203
0.0047
0.0047
0.0051
0.0051
0.0041
0.0049
CO (g/km)
NOx (g/km)
Unc orrec t ed
Correc t ed
Unc orrec t ed
0.6445
0.4884
0.6336
0.5258
0.6274
0.5835
0.4210
0.3945
0.4929
0.4016
0.4500
0.3873
0.4222
0.2804
0.4148
0.3423
0.4186
0.4113
3.9833
4.0742
3.7161
4.1699
3.8371
4.0022
0.5360
0.4745
0.5179
0.4657
0.5165
0.4757
3.0901
2.6578
3.0400
2.6488
3.0173
2.9530
0.0726
0.0725
0.0700
0.0676
0.0676
0.0728
0.0232
0.0276
0.0244
0.0253
0.0265
0.0235
0.0067
0.0059
0.0057
0.0055
0.0060
0.0074
0.2694
0.2522
0.2736
0.2685
0.2413
0.2452
0.1857
0.1978
0.1968
0.1998
0.2132
0.1995
0.0233
0.0255
0.0269
0.0245
0.0237
0.0233
0.1531
0.1318
0.1353
0.1419
0.1551
0.1452
0.6714
0.7865
0.6054
0.7940
0.7722
0.6804
0.0839
0.0876
0.0861
0.0819
0.0897
0.0823
0.6355
0.4734
0.6366
0.5228
0.6424
0.5925
0.0488
0.0461
0.0440
0.0419
0.0449
0.0438
0.0040
0.0037
0.0038
0.0034
0.0041
0.0035
0.0125
0.0140
0.0116
0.0137
0.0116
0.0115
0.1823
0.1893
0.1781
0.1875
0.1952
0.1813
0.0063
0.0070
0.0066
0.0086
0.0072
0.0095
0.0047
0.0053
0.0048
0.0055
0.0055
0.0050
0.0028
0.0026
0.0025
0.0027
0.0026
0.0026
0.0005
0.0005
0.0001
0.0007
0.0009
0.0003
0.0016
0.0033
0.0027
0.0029
0.0027
0.0015
0.0043
0.0037
0.0018
0.0025
0.0034
0.0027
0.0049
0.0052
0.0043
0.0054
0.0061
0.0050
0.0086
0.0049
0.0042
0.0045
0.0049
0.0059
0.0441
0.0530
0.0488
0.0475
0.0474
0.0467
0.0013
0.0023
0.0011
0.0019
0.0023
0.0014
0.0023
0.0023
0.0023
0.0023
0.0024
0.0023
0.0739
0.0747
0.0695
0.0680
0.0654
0.0715
Correc t ed
0.0042
0.0035
0.0019
0.0025
0.0036
0.0028
0.0081
0.0049
0.0048
0.0034
0.0059
0.0062
0.0023
0.0023
0.0023
0.0023
0.0024
0.0023
A6.2 CO2 emissions and fuel and energy consumption
CYCLE
VEHICLE
FUEL
FUEL NAME
CO2 (g/km)
Unc orrec t ed
NEDC
US06
50 km/h
90 km/h
120 km/h
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
A6.3 Particle emissions
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
161.1
160.0
160.2
159.7
161.6
160.9
166.0
165.0
164.1
163.7
166.6
165.5
159.3
158.7
158.5
158.8
160.5
159.5
173.6
174.1
173.6
173.6
175.9
174.3
184.7
184.8
183.1
183.2
185.5
185.7
183.9
182.9
183.1
183.1
184.7
183.8
92.0
92.4
92.4
92.6
93.3
92.2
95.5
95.6
95.6
94.8
95.8
96.4
88.4
89.1
88.1
87.9
89.2
88.6
120.9
121.6
121.1
121.5
122.3
121.2
127.6
129.2
128.2
128.0
129.7
130.0
125.1
125.9
125.2
125.1
126.6
125.2
177.8
178.0
177.6
177.8
179.4
177.6
183.6
184.4
183.2
183.8
185.9
185.7
180.1
180.8
180.2
179.5
182.2
180.1
Fuel consumption (g/km)
Correc t ed
Unc orrec t ed
95.7
95.9
95.5
94.8
95.8
96.1
51.37
52.76
52.46
52.93
51.20
52.22
52.74
54.30
53.62
54.15
52.66
53.57
50.62
52.17
51.76
52.49
50.73
51.65
56.98
59.23
58.40
59.40
57.30
58.28
58.68
60.81
59.76
60.57
58.60
60.09
59.73
61.31
61.08
61.68
59.58
60.75
29.15
30.33
30.09
30.55
29.39
29.75
30.23
31.36
31.10
31.22
30.14
31.09
27.96
29.19
28.64
28.94
28.06
28.56
38.41
40.00
39.52
40.17
38.60
39.22
40.47
42.45
41.77
42.25
40.91
42.01
39.60
41.28
40.71
41.23
39.84
40.38
56.32
58.43
57.79
58.65
56.52
57.33
58.41
60.84
59.86
60.94
58.87
60.19
57.01
59.30
58.62
59.17
57.36
58.11
Fuel consumption (l/100km)
Energy consumption (MJ/km)
Correc t ed
Unc orrec t ed
Correc t ed
Unc orrec t ed
Correc t ed
30.29
31.43
31.06
31.23
30.14
31.00
6.981
7.082
7.146
7.149
6.898
7.077
7.167
7.289
7.304
7.314
7.094
7.259
6.879
7.002
7.051
7.089
6.835
6.999
7.742
7.950
7.955
8.022
7.719
7.898
7.974
8.163
8.141
8.181
7.894
8.144
8.117
8.230
8.320
8.331
8.026
8.233
3.961
4.071
4.099
4.126
3.959
4.032
4.108
4.209
4.236
4.217
4.060
4.214
3.799
3.919
3.901
3.908
3.780
3.871
5.219
5.370
5.383
5.426
5.200
5.315
5.500
5.698
5.690
5.706
5.511
5.694
5.381
5.541
5.545
5.568
5.367
5.472
7.654
7.842
7.872
7.921
7.614
7.770
7.937
8.166
8.155
8.230
7.930
8.157
7.747
7.959
7.985
7.992
7.727
7.875
4.116
4.218
4.231
4.218
4.060
4.201
2.236
2.213
2.234
2.219
2.227
2.231
2.295
2.277
2.284
2.271
2.290
2.288
2.203
2.188
2.204
2.201
2.206
2.206
2.480
2.484
2.487
2.490
2.492
2.490
2.554
2.550
2.545
2.540
2.548
2.567
2.599
2.571
2.601
2.586
2.591
2.595
1.269
1.272
1.281
1.281
1.278
1.271
1.316
1.315
1.324
1.309
1.311
1.328
1.217
1.224
1.220
1.213
1.220
1.220
1.671
1.678
1.683
1.684
1.679
1.676
1.761
1.780
1.779
1.771
1.779
1.795
1.723
1.731
1.734
1.729
1.733
1.725
2.451
2.450
2.461
2.459
2.458
2.449
2.542
2.552
2.550
2.555
2.560
2.571
2.481
2.487
2.497
2.481
2.495
2.483
1.318
1.318
1.323
1.310
1.311
1.324
CYCLE
NEDC
US06
50 km/h
90 km/h
120 km/h
VEHICLE
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
FUEL
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
1
2
3
4
5
6
FUEL NAME
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Base Fuel
E10 Matched
15% ETBE
E10 Splash
High Octane
E5 Splash
Particle mass (mg/km)
Particle number (#/km)
(geometric means)
Unc orrec t ed
Correc t ed
Unc orrec t ed
Correc t ed
0.607
0.597
0.582
0.589
0.561
0.637
0.871
0.750
0.825
0.613
0.888
0.739
0.337
0.459
0.360
0.355
0.375
0.439
4.390
3.985
3.221
2.889
3.745
3.409
0.857
0.697
0.888
0.825
0.918
0.756
0.629
0.595
0.458
0.590
0.673
0.659
0.635
0.642
0.573
0.598
0.516
0.610
2.733E+10
2.161E+10
2.540E+10
2.367E+10
2.757E+10
3.199E+10
1.243E+12
1.271E+12
1.055E+12
1.058E+12
1.410E+12
1.239E+12
9.580E+09
9.736E+09
1.319E+10
1.149E+10
1.169E+10
1.825E+10
8.937E+11
6.140E+11
4.899E+11
4.904E+11
7.721E+11
6.649E+11
1.698E+12
1.624E+12
1.679E+12
1.696E+12
1.694E+12
1.630E+12
3.727E+10
3.197E+10
4.904E+10
2.231E+10
5.921E+10
9.167E+10
8.468E+08
2.036E+09
1.186E+09
1.210E+09
6.265E+08
1.747E+09
7.468E+10
1.121E+11
5.949E+10
6.309E+10
7.756E+10
8.225E+10
3.410E+09
6.602E+09
1.528E+09
9.014E+09
2.474E+09
1.871E+09
7.679E+08
1.297E+09
9.962E+08
7.878E+08
5.987E+08
1.016E+09
6.008E+11
5.639E+11
4.940E+11
5.341E+11
5.953E+11
5.973E+11
2.839E+09
3.432E+09
1.218E+09
3.741E+09
1.514E+09
1.215E+09
4.209E+09
3.191E+09
2.515E+09
2.355E+09
2.083E+09
3.380E+09
1.442E+12
1.306E+12
1.440E+12
1.426E+12
1.468E+12
1.463E+12
3.630E+09
3.979E+09
4.142E+09
3.723E+09
3.446E+09
3.847E+09
2.800E+10
2.482E+10
2.437E+10
2.567E+10
2.479E+10
2.997E+10
1.263E+12
1.338E+12
9.712E+11
1.053E+12
1.399E+12
1.236E+12
0.351
0.456
0.353
0.395
0.333
0.424
0.868
0.711
0.871
0.823
0.913
0.755
9.521E+11
6.823E+11
4.797E+11
5.008E+11
6.948E+11
6.241E+11
1.724E+12
1.687E+12
1.649E+12
1.710E+12
1.701E+12
1.536E+12
4.088E+10
3.847E+10
4.269E+10
3.796E+10
4.186E+10
6.117E+10
2.999E+09
5.106E+09
1.853E+09
4.306E+09
4.005E+09
3.282E+09
6.087E+11
5.724E+11
4.894E+11
5.351E+11
5.953E+11
5.851E+11
2.556E+09
2.782E+09
1.425E+09
2.045E+09
2.245E+09
1.924E+09
1.481E+12
1.346E+12
1.413E+12
1.431E+12
1.468E+12
1.403E+12
European Commission
EUR 26381 – Joint Research Centre – Institute for Energy and Transport
Title: Effect of oxygenates in gasoline on fuel consumption and emissions in three Euro 4 passenger cars
Author(s): G. Martini, U. Manfredi, A. Krasenbrink, (Joint Research Centre), R. Stradling, P.J. Zemroch, K. D. Rose
(CONCAWE), H. Hass, H. Maas (EUCAR)
Luxembourg: Publications Office of the European Union
2013 – 61 pp. – 21.0 x 29.7 cm
EUR – Scientific and Technical Research series – ISSN 1831-9424 (pdf), 1018-5593 (print),
ISBN 978-92-79-34883-9 (pdf)
ISBN 978-92-79-34884-6 (print)
doi: 10.2790/1136
Abstract
The Joint Research Centre (JRC) of the European Commission, the European Council for Automotive R&D (EUCAR), and
CONCAWE jointly completed this vehicle test programme to investigate the effect of oxygenates in gasoline on the fuel
consumption, regulated emissions, and particle emissions of three passenger cars homologated at the Euro 4 emissions
level. Substituting oxygenates for hydrocarbons in gasoline decreases the overall energy content of the resulting blend
which is also expected to increase the volumetric fuel consumption needed to achieve the same vehicle driving cycle.
For this reason, a major objective of this study was to determine whether today’s gasoline vehicles can improve their
efficiency when running on oxygenate/gasoline fuel blends and reduce this volumetric fuel consumption penalty. In
addition to a 95 Research Octane Number (RON) base gasoline, five other specially blended fuels were evaluated that
varied in RON, oxygen content, and oxygenate type. Results are compared for the New European Driving Cycle (NEDC),
the US06 part of the US Supplemental Federal Test Procedure (SFTP), and three constant speeds.
Over all vehicle test conditions, the results show that the volumetric fuel consumption (FC) increases in direct proportion
to the decrease in the fuel’s volumetric energy content. Except possibly for one vehicle over one test cycle, the results
show that the use of oxygenates or higher octane did not provide a volumetric FC benefit. This means that these Euro 4
passenger cars were not able to compensate for the lower energy content of oxygenated fuels through better engine
efficiency for the variation in fuel properties investigated in this study.
LD-NA-26381-EN-N
As the Commission’s in-house science service, the Joint Research Centre’s mission is to provide
EU policies with independent, evidence-based scientific and technical support throughout the
whole policy cycle.
Working in close cooperation with policy Directorates-General, the JRC addresses key societal
challenges while stimulating innovation through developing new standards, methods and tools,
and sharing and transferring its know-how to the Member States and international community.
Key policy areas include: environment and climate change; energy and transport; agriculture
and food security; health and consumer protection; information society and digital agenda;
safety and security including nuclear; all supported through a cross-cutting and multidisciplinary approach.