ABSTRACT
Falling cost of solar photovoltaic (PV) generated electricity has led to a rapid increase in the deployment of PV and projections that PV could play a significant role in the future U.S. electric sector. The solar resource itself is virtually unlimited compared to any conceivable demand for energy (Morton 2006); however, the ultimate contribution from PV could be limited by several factors in the current grid. One is the limited coincidence between the solar resource and normal demand patterns (Denholm and Margolis 2007a). A second is the limited flexibility of conventional generators to reduce output and accommodate this variable generation resource. At high penetration of solar generation, increased grid flexibility will be needed to fully utilize the variable and uncertain output from PV generation and shift energy production to periods of high demand or reduced solar output (Denholm and Margolis 2007b).
