Energy and exergy analysis of a multi-stage hybrid concentrated solar power plant

The Colombian electricity sector is mainly composed of hydropower plants covering up to 70% of the total power generation. Several alternatives had been evaluated to complement Colombian's energy mix, including solar PV and wind energy plants; however, there is no consensus about the appropriate solution in terms of the available resource, energy demand, and energy mix complementing. This work presents the performance evaluation of a hybrid thermosolar power plant at a city on the Caribbean Colombian coast, considering local environmental conditions such as ambient temperature and solar resource availability to attain the factor that constrain its optimal operating conditions. The overall energy and exergy plant efficiency is analyzed, considering an arbitrary number of stages. For instance, comparing a single-stage plant running with air with a two compression stages with inter-cooling and two expansion stages with reheating, the results indicate a 30 % higher exergy efficiency, and overall energy efficiency about 32 % larger and a fuel conversion rate around 18 % larger.