In 1986 the U.S. Department of Energy (DOE) entered into a cooperative agreement with three Southwest utilities for a study entitled "Solar Central Receiver Technology Advancement for Electric Utility Applications". The goals of this two-phase study were to select the most promising technology for near-term applications, and to define an appropriate plan to commercialize the technology [1-4]. This report summarizes the results of PhaseIIC, an evaluation of a plan to convert the 10 MW(e) Solar Central Receiver Pilot Plant ("Solar One") [5] to advanced nitrate salt technology. The project, called the Solar One Conversion Project, involves removing the existing water/steam receiver, piping, thermal storage tank, charging and discharging heat exchangers and oil transfer pumps. These will be replaced with a new nitrate salt receiver, piping, salt transfer pumps, thermal storage tanks, steam generator system and gas-fired salt heater to provide a fully functioning hybrid solar/fossil central receiver power plant. Performance of the existing turbine plant will be augmented through an additional stage of feedwater heating and an upgraded master control system. The conceptual design, capital and O&M cost estimates, and annual performance estimate for the Solar One Conversion Project are described below.
