in the following subsection. Examples for solar include the DOE’s Solar America Initiative (DOE, 2007b), the photovoltaics industry roadmap (SEIA, 2001, 2004), and the 10 percent solar study (Pernick and Wilder, 2008). These scenarios consider issues similar to those of the 20 percent wind power scenario, namely, the potential impacts of high renewables penetration on manufacturing, implementation, economics, and the environment. In addition, because of the higher costs associated with solar energy, all solar scenarios take into account the significant cost reductions that need to occur to make solar electricity widely competitive with other electricity sources.
The second type of scenario involved the interaction of renewables with other sources of electricity, other forms of energy, and end-use demands (U.S. Climate Change Science Program, 2007; EIA, 2008b). With the aid of long-term energy/economic models, these scenarios allow the potential influences of demographic, economic, and regulatory factors on renewable electricity to be assessed within a framework that considers how such factors interrelate with other sources of electricity and end-use energy demands.
The most in-depth scenario describing increased renewables penetration into the electricity sector is the DOE’s 20 percent wind penetration scenario (DOE, 2008a), which, as its name implies, examines the implications of increasing wind power’s contribution to 20 percent of total U.S. electricity generation by 2030. The DOE developed this scenario in collaboration with the National Renewable Energy Laboratory (NREL), Lawrence Berkeley National Laboratory, and the American Wind Energy Association. The effort relied on contributions from more than 90 individuals, including stakeholders in the electric utility industry, wind power developers, engineering consultants, and staff members of environmental organizations. These individuals participated in every stage of the study, including its planning process, workshops, steering-group meetings, chapter writing, and review and oversight. The U.S. Office of Management and Budget (OMB) defined the report resulting from the effort as potentially “influential scientific information” disseminated by the agency, thereby requiring that the report be reviewed subject to the Information Quality Bulletin for Peer Review (OMB, 2004).
The DOE’s 20 percent wind scenario includes an assessment of wind resources and available technologies; manufacturing, materials, and labor requirements; environmental effects and siting issues; transmission system integration;