Many of the significant externalities associated with electricity generation can be estimated quantitatively, but there are several important areas where additional research is needed:
Although it appears that upstream and downstream (pre- and post-generation) activities are generally responsible for a smaller portion of the life-cycle externalities than the generation activities themselves for some sources, it would be useful to perform a systematic estimation and compilation of the externalities from these other activities, comparable in completeness to the externality estimates for the generation part of the life cycle. In this compilation, damages from activities that are locally or regionally significant (for example, the storage and disposal of coal combustion by-products, in situ leaching techniques for uranium mining) need to be taken into account.
The “reduced-form” modeling of pollutant dispersion and transformation is a key aspect in estimating externalities from airborne emissions, which constitute most of the estimated externalities for fossil-fuel-fired power plants. These models should continue to be improved and tested and compared with the results of more complex models, such as CMAQ.
The health effects associated with toxic air pollutants, including specific components of PM, from electricity generation should be quantified and monetized. Because of the importance of VSL in determining the size of air-pollution damages, further exploration is needed of how willingness to pay varies with mortality-risk changes and with such population characteristics as age and health status.
For fossil-fuel options, the ecological and socioeconomic impacts of coal mining, for example, of mountaintop removal and valley fill, are a major type of impact in need of further research in to quantify their damages.
For nuclear power, the most significant challenges in estimating externalities are appropriately estimating and valuing risks when the probabilities of accidents and of radionuclide migration (for example, at a high-level waste repository) are very low but the consequences potentially extreme, and whether the cost to utilities of meeting their regulatory requirements fully reflects these externalities.
The analysis of risks associated with nuclear power in the RFF/ORNL study should be updated to reflect advances in technology and science.
For wind technologies, the major issues are in quantifying bird, and especially bat deaths; disturbances to both the local animal populations and landscape; and valuing them in terms comparable to economic damages.