The chapters and supporting annexes in Part 2 of this report provide the AEF Committee’s detailed technical assessments of the energy-supply and end-use technologies that it judged were most likely to have meaningful impacts on the U.S. energy system during the three time intervals considered in this study: 2009–2020, 2020–2035, and 2035–2050. The assessments were used to inform the committee’s judgments about what could happen as a result of accelerated deployments of existing and new technologies. They are not forecasts of what will happen, however. As is noted in Chapter 1, the potential energy supply (or savings) and cost estimates presented in this report were developed independently for each class of technologies. The AEF Committee did not conduct an integrated assessment of these technologies to understand, for example, how policies, regulations, and market competition would affect energy savings, supplies, and costs. Predicting the nature and impacts of such policies and regulations on investments in particular energy-supply and end-use technologies and their deployment is well beyond the scope of this study. Consequently, the estimates provided in thesechapters should not be viewed as predictions.