Preliminary design and assessment of concentrated solar power plant using supercritical carbon dioxide Brayton cycles

Abstract

In pursuit of efficient renewable electricity generation at a utility scale, concentrating solar power using receiver tower and heliostat field is one of the most prominent technologies due to its high achievable temperatures and environmental impact reduction. To increase the operating performance of this technology, innovative approaches have been focused on the heliostat field, thermal energy storage, and the integrated power cycle. Brayton cycles using supercritical carbon dioxide have emerged as an alternative to the traditional Rankine cycle for their compactness and superior performance even at extreme climate temperatures. In this work, a suite of code is developed to calculate expressively influencing parameters of the central receiver system, such as the exhaustive design of heliostat field pattern, characteristics angles, optical efficiency, and thermal energy storage, coupled with two Brayton cycle configurations. The seasonal effect on the performance of solar power plants is presented at different climatic conditions in terms of net power generation and cycle efficiency using the daily meteorological data. The year-round performance is assessed by statistically distributing the historical air temperature data into four categories. The proposed systems operate continually for 24 h with heat transfer fluid following a sinusoidal curved movement between the solar receiver and storage tanks. The findings demonstrate that the efficiency of the coupled system is higher with recompression cycle configuration while the fluctuation range is 39% to 45%. The computed mean net power output is 37.17 MW and 39.04 MW using regenerative and recompression cycles, respectively. The developed exhaustive methodology and computed results are of significance for future employment of supercritical carbon dioxide Brayton cycle for concentrated solar power plants.