The primary objectives: to provide a broad range of analytical support to the Solar Program; and to anticipate and respond to the rapidly evolving analytical needs of the Solar Program. Three broad types of analysis are being carried out under this project including: (1) Market analysis: Developing a PV market penetration model--the SolarDS model--and other tools, in order to gain insight into the factors influencing market penetration of PV technology in U.S. markets. (2) Value analysis: Providing inputs to, support for, and review of the annual GPRA benefits analysis. Also developing methods and tools for improving the quantification of the benefits and cost of solar technologies. (3) Policy analysis: Defining and carrying out analysis that meets the needs of the Solar Energy Technologies Program in a timely fashion, for example evaluating the potential role of solar in the energy economy in the long-term.