The solar-aided power generation (SAPG) technology has been proven to be one of the most efficient ways to integrate solar thermal energy into coal-fired power plants. An open question is whether to integrate the SAPG plant with a thermal energy storage system (TES). Conventionally, most SAPG plants are not designed to include TESs due to high costs and challenges related to the intermittent nature of solar energy. To address this question, a realisti. The solar-aided power generation (SAPG) technology has been proven to be one of the most efficient ways to integrate solar thermal energy into coal-fired power plants. An open question is whether to integrate the SAPG plant with a thermal energy storage system (TES). Conventionally, most SAPG plants are not designed to include TESs due to high costs and challenges related to the intermittent nature of solar energy. To address this question, a realistic case study utilizing a 330MWe SAPG plant is investigated in this paper. The simulation shows that when the SAPG plant uses a TES with a proper regulation strategy, the energy efficiency of the SAPG can be increased by 2.5% and the levelized cost of electric energy (LCOE) can be reduced by 0.27 cents/kWh. A well-regulated TES does not deteriorate the economic performance of the SAPG plant here and has a positive impact on its operational safety (especially under sudden irradiance change). To the best of authors' knowledge, this is the first time to study the operational strategies of TES (based on the operating characteristics of the SAPG systems) and to combine them with the TES's size optimization to maximize the techno-economic performance of the SAPG plant.••••A comprehensive, multi-criteria comparison of various TES regulation strategies is investigated.••Common misconception that TES inevitably deteriorates the economics of SAPG is clarified.••Active regulation of TES reduces LCOE by 0.4 cents/kWh compared to conventional (passive) regulation strategy.••Well-regulated TES enhances the energy efficiency by 2.5% compared with a TES-less case.Energy efficiencyOperational safetyOperational strategiesSolar-aided power generation (SAPG)Thermal energy storage (TES)Thermal solar-coal integrationAhot Bottom area of the hot tank (m2)Asf Area aperture of solar field (m2)AF Annuity factorCcapital Increased total capital cost of SAPG plant ($)CHTF Heat capacity of HTF (kJ/°C·kg)CO&M Due to the shortage of fossil fuels and their adverse effects on the environment, the focus is gradually shifting towards renewable energy sources, such as wind and solar energy. Wind power and photovoltaic (PV) are gaining worldwide popularity as large-scale energy sources due to their reliability and low cost. However, electric power generated from wind power or solar PV power can be highly variable at different timescales. Since instantaneous electrical generation and consumption must be balanced to maintain grid stability, such variability can present substantial challenges for incorporating large amounts of wind/PV power into the grid system.In this context, solar thermal energy has attracted the interest of the industry in recent years. A thermal energy storage system (TES) allows a concentrating solar power (CSP) plant to generate electricity both at night and on overcast days. This allows the use of solar power for baseload generation as well as for dispatchable generation to achieve carbon-neutral operation, which has the potential of substituting fossil fuel power plants in the long run. However, conventional CSP plants are suffering development restrictions due to their high cost and relatively low efficiency.As a response, solar-aided power generation (SAPG) technology was propos.
