How to diminish the carbon
footprint of asphalt roads
Ir.Jan van der Zwan
Rijkswaterstaat
The Netherlands
Source figure: PBL Netherlands Environmental
Assessment Agency
CO2 emission and Asphalt
• CO2 emission transport
app. 4700 Mton
• Global annual asphalt
production 1600 million
ton / year
• Equals app. 96 Mton CO2
• ~2% of emission of road
transport
Asphalt and other products
• Carbon footprint
asphalt
60 g CO2e /kg
• Carbon footprint
orange jus
1600 g CO2 e/kg
• Carbon footprint
cheese burger
6000 g CO2 e
How to reduce the
carbonfootprint
• Production constituent
materials (aggregates,
binder, filler, additives)
• Transport materials to
production place
• Asphalt production
(heating, mixing,…)
• Transport asphalt
• Laying and compaction
• Maintenance
• Demolition and re-use
• Foto’s van verschillende
zaken
Carbon footprint
asphaltconstruction
Maintenance (exl. materials) 7%
Laying and
compaction
18%
Asphalt
production
31%
Production and
transport raw
materials 44%
Circle of influence
• In the process of road building degrees of freedom
becomes less to influence sustainability
(Planning, design, construction, use)
• No road is no carbon footprint
• In this presentation mainly the construction/maintenance
phase will be addressed
Who takes responsibility?
• Contractor
– Can influence all steps
in the production chain
– How to built, with what
• Client
– Can influence the
demand
– What does he wants,
where, when.
Contractor
• Investigate the total production chain, define the
carbon footprint of all activities.
– (A.o.) better supply chains
– Isolation of asphalt plant
– Low temperature asphalt
– Increase recycling
– Low emission engines
– Green energy
Client
• Reduce number of tons needed (Over total life cycle)
– Increase technical quality (durability)
– Rethink design and maintenance strategies
• Thinner constructions using high performance
materials
• Reduce amount materials for maintenance
– Higher recycling percentages
Life cycle approach
• Always look at the life
cycle effects
• At least the same
functionality should be
achieved
– Example: lower
asphalt temperature is
meaningless if
durability is reduced or
if recycling in mix is
not possible
Drivers
• The European
commission CPR
• CEN TC 227 road
materials is discussing
this issue
• CEN TC 351 is dealing
with dangerous
substances
• CEN TC 350 is
developing instruments
for sustainability
• BWR 3: release of dangerous
substances
• BWR 6: Energy economy and
heat retention
• BWR 7:Sustainable use of
natural resources
ERA-NET Road: Energy
• SUNRa Sustainability- National •
Road Administrations
•
• LICCER - Life Cycle
Considerations in EIA of Road
Infrastructure
• CEREAL - CO2 Emission
REduction in roAd Lifecycles
•
• MIRAVEC -Modelling Infrastructure
influence on RoAd Vehicle
Energy Consumption
Financing countries:
Germany, Denmark,
Ireland,
Netherlands, ,
Norway, Sweden,
United Kingdom
www.eranetroad.org
WRAP
Highways Agency Carbon
Calculatortool
Dubocalc
JouleSAVE
CO2NSTRUCT
WLCO2T
CO2
ladder
PaLATE
ROAD-RES
asPECT
Green Roads
AggRegain
LCI Model
GHG calculator for
infrastructure
Ecologiciel
SEVE
AMW
GreenDot
Methodology
• Most of them are based
on a Life Cycle
Assessment
• Input data on amounts of
materials over the life
cycle
• Environmental data
related to the materials
and techniques applied
• Weigh the different
environmental aspects
• Text
• Text
Quality of assessment
• EN standards are being developed by TC350
– EN 15978-2011: Sustainability of construction worksAssessment of environmental performance of
construction works-calculation method
• Method for buildings
not for road construction
• A EN-standard for road works.
• Also a need for European procedures for
databanks and the way data are validated or
accepted
• Method for validation new products
Possible use of instrument(s)
• Optimisation of
construction design or
maintenance strategy
over life cycle
• In contracts
– Minimum standard
– Process requirement
– Award criterion
• Economical Most
Valuable bit
Money makes the world go
round
• On a technical level (almost) everything is possible
• What is the ambition of the client and or the contractor?
• How much is a client willing to pay for a lower carbon
footprint?
• How consistent is his policy?
• Not everything costs money, lower energy costs are
beneficial for the contractor too.
Other possibilities?
• Highest emissions by traffic
• How to influence energy use by traffic?
– Reduce rolling resistance
– Reduce aerodynamic resistance
– Traffic management
– Speed
Conclusions
• Yes, we can…….. reduce the carbon footprint of roads
• Always take the life cycle effects into account
• Large effect by reducing amounts of asphalt (increase
quality, rethink design and maintenance strategies)
• Reduce energy use in total production line
• Be clear about ambition and costs
• There is a need for standardisation in instruments and
quality management of data
• Use the possibilities to reduce energy use by traffic
Thank you for your kind attention