Solar central receiver technology advancement for electric utility applications. Phase 2C, topical report

In 1986 the US Department of Energy 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. This report summarizes the results of Phase IIC, an evaluation of a plan to convert the 10 MWe Solar Central Receiver Pilot Plant (Solar One) to advanced nitrate soft 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 soft receiver, piping, salt transfer pumps, thermal storage tanks, steam generator system and gas-fired soft 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, as developed during Phase IIC of the Utility Study, are described.