ExternE Core/Transport


The supply and use of energy imposes risks and causes damage to a wide range of receptors, including human health, natural ecosystems (flora and fauna) and the built environment. Such damages are to a large extent external costs, as they are not reflected in the market price of en-ergy. In the former stages of the ExternE Project a methodology for externality quantification for energy conversion processes was developed and applied to the sectors electricity generation and transport. Within this project the general methodology was improved and extended. With the improved methodology energy-related transport externalities were assessed.

Technical approach

  • The impact pathway approach is the methodology for externality quantification developed in the ExternE Project. Impacts due to airborne pollutants are quantified modelling emission and dispersion (including chemical transformation processes) of pollutants, leading to changes in ambient air concentrations from which impacts can be quantified using exposure-response functions. The impact pathway approach emphasises the valuation of marginal impacts rather than general perceptions of the state of the whole environment.
  • In the project the methodology was extended and improved in many fields: climate change models used for estimating global warming impacts have been improved, updated and extended. Knowledge and data on local, regional and global scale ozone were reviewed and provided. Monetary valuation issues were reviewed and possibilities for integrating sustainability indicators into the modelling framework were explored. Exposure-response models were reviewed, updated and extended. Work on the validation of results was undertaken. The issue of dispersion modelling on the kerbside scale was addressed. Tools and data for life cycle impact assessment were provided, and a computer tool for assessing transport-related impacts was developed.
  • Computer tool and improved methodology were used to extend the accounting framework of transport-related externalities, i.e. external costs were quantified for all modes, for current and future technologies and for various locations in the European union (Belgium, Germany, Spain, Finland, France, Greece, Netherlands, United Kingdom). Location-specific marginal external costs were aggregated for transport in and outside urban areas. The resulting methodology and data were applied in a number of policy case studies.

Achievements and exploitation

In the project major remaining issues in the ExternE methodology were addressed and the transport accounting framework and the respective tools are available so that the framework is ready for broad dissemination and application. Hence, the transport accounting framework and tools will support activities on different aggregation levels as e.g.

  • assessing transport techniques in different areas (urban or regional transport),
  • analysing single European transport tasks in order to compare different transport systems,
  • providing a methodology for supporting the application of environmental policy instruments in the transport sector,
  • green accounting at the national and European levels.


Publishable report (PDF file, 22 pages)

The final report was published as:
Friedrich, Rainer; Bickel, Peter (Eds.): Environmental External Costs of Transport. Springer-Verlag, Berlin/Heidelberg/New York 2001.