Integrating thermal energy storage in power plants

This article describes a system that stores thermal energy in a natural gas-fired cogeneration facility uses a gas turbine, a heat recovery salt heater, and salt-heated steam generator. The National Energy Strategy forecast estimates that 200,000 megawatts-electric (MWe) of new electric-generating capacity will need to be added to the US nationally by the year 2010. Approximately 40 percent of this new generating capacity will be for peak or intermediate loads, with the rest providing continuous baseload power generation. Natural gas-fired combustion turbine technologies, including cogeneration, combined-cycle, and integrated gasification combined-cycle power plants, are becoming the generating options of choice because of their flexibility, relatively low capital cost, reduced environmental impact, and increasing thermal efficiency. Thermal energy storage (TES) for utility applications includes a range of technologies that can further improve the efficiency, flexibility, and economics of gas turbine options.