impact of one technology over another. Environmental valuation methods attempt to do this by estimating the overall ecosystem impact of a technology using currency or “willingness to pay” as the unit to integrate across types of impacts. Impact categories included in environmental valuation methods typically relate to damages to humans, ecosystems, and resources. ExternE (European Commission, 1997) and Eco-indicator 99 (Pre Consultants, 2007a) are examples of environmental valuation methods used in Europe.

The main criticism of environmental valuation methods is of the step where disparate effects of LCAs are weighted and normalized into a single value per technology. Often the development of a single value is not adequate to capture the complexities of a technology, and metrics like “willingness to pay” can vary over time. For this reason we limit our discussion to LCA results.

Ecobilan, P. 2001. TEAM/DEAM. 2001. Bethesda, Md.: PriceWaterhouseCoopers.

European Commission. 1997. External Costs of Electricity Generation in Greece. ExternE Project. Brussels.

Frankl, P., Corrado, A., and S. Lombardelli. 2004. Photovoltaic (PV) Systems. Final Report. ECLIPSE (Environmental and Ecological Life Cycle Inventories for present and future Power Systems in Europe). Brussels: European Commission. January.

Franklin Associates. 2008. Available at http://www.fal.com/lifecycle.htm.

Fthenakis, V.M., and H.C. Kim. 2007. Greenhouse-gas emissions from solar-electric and nuclear power: A life-cycle study. Energy Policy 35:2549-2557.

Odeh, N.A., and T.T. Cockerill. 2008. Life cycle GHG assessment of fossil fuel power plants with carbon capture and storage. Energy Policy 38:367-380.

Pre Consultants. 2007a. Available at http://www.pre.nl/eco-indicator99.

Pre Consultants. 2007b. Available at http://www.pre.nl/ecoinvent/.