Performance evaluation of the combined solar chimney-photovoltaic system in Algeria

Abstract

The demand for solar energy technologies is increasing due to the growing interest in renewable energy. However, these technologies are affected by atmospheric conditions and low overall efficiency. The present study proposes a combined solar chimney-photovoltaic (SC-PV) system to deal with stand-alone system weaknesses. This work evaluates this self-sustainable system's performance and estimates the electric energy generated under the climatic conditions of Algeria using computational fluid dynamics (CFD). The model is first validated using the Spanish prototype experimental data. The simulations show that the proposed system provides several valuable benefits for improving turbine power, solar cell temperature, and PV efficiency. The results indicate the SC in the combined system performs better turbine generated power than a stand-alone system only for an appropriate PV location and width. Using the heat released from the PV to increase the kinetic energy of airflow beneath the collector, the total improvement in turbine power reaches 8.91%. Similar to the optimal PV widths (10 m), other widths, varying from 20 m to 30 m, increase the overall turbine power without degrading SC performance. Using the SC-PV as a cooling method, the solar cell temperature decreases by 12.12% (6.30 °C) compared with cell temperature in the stand-alone system (52 °C). Accordingly, the PV efficiency increases by 3.23% compared with PV efficiency in the stand-alone system (13.18%). The results also indicate the highly intensive solar radiation region (Adrar) has higher monthly turbine power than other areas. The appropriate areas for building such a system will be in the south of the country, where the solar potential is high. In these regions, the SC-PV could contribute to satisfying the electricity demand.