Review of work on whole-life environmental impacts of vehicles

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Executive Summary

This summary brings together the conclusions of the research into the current 'state of the art' in the measurement of whole life costs for vehicles and fuels.

Life cycle assessment

Life cycle assessment (LCA) is a reasonably well-established method to measure the environmental burden of products and / or materials including fuels. The main strengths are:

  • Comprehensive treatment of the entire supply chain from raw materials extraction to product use and disposal;
  • Exposure and measurement of the main environmental impacts arising from a product and / or material;
  • Credibility arising from the 'scientific' basis of LCA.

However, as LCA methods mature, so the limitations of such an approach across all fields of application have become apparent. The major problems include:

  • Recourse to arbitrary judgements as to the relative significance of different types of environmental burden;
  • The geographically-bounded nature of the analysis;
  • The inability to resolve LCA into a single metric that would allow unambiguous comparison;
  • Recourse to 'generic' product types and production / process technologies in a manner that does violence to the diverse reality of actual products and processes;
  • Implicit forecasts of in-use and post-use environmental burdens;
  • Failure to address economic issues (such as the capital structure of production) or social issues within a wide vision of sustainable industry;
  • Large data requirements.

LCA can be useful to assess aggregate, industry-sector level environmental burdens, or to compare one set of technologies with another.

Life cycle assessment in the automotive industry: vehicles, manufacturing facilities and fuels

As one of the most complex and largest industrial sectors, the automotive industry represents a particular challenge for LCA studies. In both North America and the EU work has been carried out at the aggregate level. This work has included:

  • Studies based on a generic vehicle and average production processes to calculate the contribution of different phases of the life cycle to the various environmental burdens;
  • Studies at a materials level;
  • Analysis of the whole life cost of petroleum fuels and alternatives;
  • Discrete studies of components and sub-assemblies;
  • Discrete (one-off) studies of individual vehicles.

None of these studies have sought to go beyond an aggregate analysis in a manner that might inform a per-model comparison. However, the techniques and software developed may be applicable to such an initiative. There remain real difficulties in translating LCA to a per-model basis. Some of the most compelling are:

  • The problem of accounting for differing levels of vertical integration when measuring manufacturing performance;
  • The problem of inclusion of the supply base;
  • The complexity of a full LCA that would involve many materials, hundreds of individual parts, and numerous processes;
  • The use of implicit forecasts of in-use performance;
  • The fundamental problem of reconciling different classes of environmental burden such that one may meaningfully be compared with another;
  • The inability to reduce whole life costs to a single metric in a neutral, objective and scientific manner that would command universal acceptance.

Environmental information in the automotive industry

There is a wide range of information available on the environmental performance of the automotive industry at a corporate level, and in terms of actual products. This includes:

  • Fuel economy guides are available from government agencies such as the US Environmental Protection Agency and the UK Department of Environment, Transport and the Regions. Car magazines often provide their own (more 'realistic') fuel economies for particular models.
  • Vehicle emission guides. As with fuel economy guides, official organisations such as the EPA and DETR provide Type Approval data. More recently the independent testing organisation Rototest has provided alternative emissions data for a sample of models available in Europe.
  • The major vehicle manufacturers produce environmental reports, although there is not necessarily consistence of data and presentation. This means that comparison between companies, and the attribution of environmental manufacturing burdens on a per-model basis, is fraught with hazard.
  • Environmental product declarations such as those Volvo has pioneered on a per-model basis, with the S80 and new S70 models.
  • Factory emissions guides. In North America a comparative guide to manufacturing emissions has been created using data provided to the US EPA under mandatory disclosure laws.
  • Vehicle environmental rating systems. Several organisations have created what are claimed to be environmental rating systems that allow consumers and others to choose the greenest car.

Environmental rating systems

The research identified several Environmental Rating Systems (ERSs) in the public domain. All may be criticised on a range of grounds, but each also seeks to present consumers with guidance as to the environmental performance of specific models. These include:

  • Rototest, an independent organisation that conducts it's own emissions tests;
  • VCD, a motorists organisation in Germany, that conducts an annual survey of vehicle manufacturers;
  • ETA, a transport organisation in the UK, that also conducts an annual survey;
  • ACEEE, a US not-for-profit organisation;
  • CAIR, a UK academic research organisation.

These efforts, however flawed, are the only guidance available to consumers and others that wish to understand the relative environmental performance of one model compared with another.

Given the lack of such an ERS from either government or industry, it is likely that independent efforts will continue to be developed - whether or not they accord with government or industry needs.

Scope for further work

An ERS as a policy tool has to be understood within the three dimensions of sustainability: environmental; economic; and social. This means consideration of issues such as:

  • Should whole life costs or environmental rating systems simply take the form of information provision, or should that information be the basis of the regulatory / fiscal regime?
  • What would be the (additional) costs of obtaining and presenting the information, assuming a format could be agreed?
  • How inclusive or exclusive should the coverage be? Are low volume vehicle manufacturers excluded? Should the information apply to every single model and variant available? Should alternatives such as hybrid vehicles be included? What about other forms of motorised transport?
  • How would such information relate to existing information on fuel economy and emissions?
  • Who will gain and who will lose from the implementation of an ERS as a policy tool?
  • What are the implications for the competitive position of UK or EU vehicle manufacturers and their suppliers?
  • Would a regulatory regime based upon an environmental rating system contravene trade rules at EU or WTO level?

An in-depth study would be the logical next step for research in this area, in particular to attempt a comparison of manufacturing performance in a manner that retains per-model applicability.

The work could be divided into two distinct phases:

  • The development of indicators of manufacturing environmental performance, that could be published in the manner of the Volvo Environmental Product Declarations;
  • The development of an Environmental Rating System that takes the indicators, combines them with indicators for in-use environmental burdens, and then manipulates the data to create a whole life cost index.