A 5-MINUTE GUIDE TO UNDERSTANDING
THE ENVIRONMENTAL IMPACT OF VEHICLES
CO2 and pollutants: not to be confused!
Pollutants have been in the media spotlight over the past few weeks. Yet the issue is far from
clear in the mind of the general public, who often confuse CO2 with pollutants.
1/ CO2 WARMS THE ATMOSPHERE BUT IS NOT A POLLUTANT
What is it?
CO2 is at the center of the debate surrounding the COP21 and occurs naturally in the
atmosphere. It is the second most abundant greenhouse gas (GHG), after water vapor.
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 How is it connected to cars?
Car engines burn fuel, which produces carbon dioxide (CO2). This is why car use contributes to
global warming. In Europe, transportation accounts for close to 25% of CO2 emissions.
Diesel vs gasoline: on average, diesel engines emit 20% less CO2 than gasoline engines.
 How can we reduce CO2 emissions?
Reducing CO2 emissions means reducing fuel consumption. There are a number of ways to
achieve this goal, such as hybrid engines, electric cars, engine downsizing, aerodynamics and
reduced rolling resistance, along with lighter vehicles and exhaust heat recovery, both of
which are areas in which Faurecia continues to develop solutions:
o Vehicle Weight Reduction:
Reducing the weight of a vehicle by 10 kg cuts CO2 emissions by 1 g/km. One of the most
effective ways of doing this involves reducing the weight of vehicle equipment by using
new, more-lightweight materials such as carbon- and glass-fiber composites, which are
stronger and lighter than steel, aluminum or magnesium. The use of biomaterials can also
reduce the weight of plastic automotive parts by 25%. Through optimized design, plus the
development and integration of alternative materials, Faurecia is in a position to offer
weight reductions of up to 100 kg per vehicle, cutting CO2 emissions by 10 g/km.
o Exhaust heat recovery:
One third of the energy in fuel is typically lost as dissipated heat in conventional exhaust
systems. Faurecia's Exhaust Heat Recovery Systems (EHRS) can capture this heat to
improve fuel efficiency by 3%, representing a reduction in CO2 emissions of 4 g/km. By
2020, solutions designed to turn that heat into electricity will make it possible to reduce
the fuel consumption (and therefore CO2 emissions) of hybrid vehicles by 10%.
2/ POLLUTANTS DO NOT WARM THE ATMOSPHERE; THEY CAUSE AIR POLLUTION
1. PARTICULATE MATTER
 What is it?
Particulate matter (PM) is a complex mix of extremely small particles and liquid droplets in the
atmosphere. It includes aerosols, smoke, fumes, dust, ash and pollen.
 How is it connected to cars?
Vehicle exhausts emit these fine particles. Yet all forms of transportation combined account for
just 16% of emissions of particulate matter smaller than 10 microns in diameter (known as
PM10), far behind industry and the service sector.

How can we reduce PM emissions?
Diesel vs gasoline:
o
Diesel Particulate Filters: an effective solution since 2009
Particulate emissions, have largely fallen in the past 20 years, especially from diesel engines.
99.97% of particulate emissions are now effectively prevented—in line with the requirements
of the Euro 5 standard introduced in 2009—by the Diesel Particulate Filters (DPF) jointly
developed by Faurecia and PSA in 2000. These filters are now used by automakers around
the world on all diesel cars currently on the market.
o
Gasoline Particulate Filters: an effective solution now being adopted
The latest direct-injection engines use less fuel and produce fewer CO2 emissions. However,
they do emit more fine particles. Faurecia has already achieved a world-first in developing a
particulate filter similar to the DPF for direct-injection gasoline engines, in anticipation of
new regulations to be introduced in September 2017.
2. NITROGEN OXIDES
 What are they?
Nitrogen oxides (NOx) are for the most part produced by burning fossil fuels, mainly resulting
from a combination of high temperatures and manufacturing processes.
 How are they connected to cars?
Contrary to popular opinion, cars account for "only" 20% of NOx emissions.
Diesel vs gasoline: diesel vehicles emit large amounts of NOx while their gasoline counterparts
give off relatively little.

How can we reduce NOx emissions?
Diesel
o Selective Catalytic Reduction (SCR)
This breakthrough incorporates a close-coupled SCR system using a urea-based fluid (AdBlue®)
that converts the nitrogen oxides into harmless nitrogen and water. The system is already being
used in conjunction with a wide array of diesel engines and is set to be adopted for diesel
vehicles across the board in the near future.
Gasoline:
o Three-way catalytic converter
Three-way catalytic converters (TWC) are used with all gasoline engines to convert nitrogen
oxides into nitrogen and water using rare metals as a catalyst.
3/ EMISSIONS STANDARDS: ROOM FOR IMPROVEMENT
Outdated driving cycles
Although regularly made more stringent, today's standards are based on the New European
Driving Cycle (NEDC), which was established 40 years ago and is now completely out of touch
with modern-day needs.

In 2017, a new cycle, known as the Worldwide harmonized Light vehicles Test Cycle (WLTC),
will make it possible to determine official emissions and consumption in more realistic
conditions.
More stringent standards in 2017
The Euro 6 standard has been in effect since September 2015 and sets thresholds for pollutant
emissions that must not be exceeded, particularly for NOx from diesel vehicles. It has similar
stringent requirements for both diesel (80 mg/km) and gasoline engines (60 mg/km).

With the introduction of Euro 6.c standards in 2017, gasoline engines will no longer be
permitted to emit ten times more particles than diesel engines, as is currently the case.
What to remember:
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
CO2 is not a pollutant; it is a greenhouse gas (GHG);
The most-targeted pollutants are particulate matter and nitrogen oxides.