Electricity I Production in South Sahara Africa Through Thermal Solar: Results and Perspectives

The generation of electricity from renewable energy sources emerges as the optimal solution to these challenges. Among these sources, solar energy is regarded as the most promising for the generation of electricity and the reduction of GHG emissions. It is an abundant, clean and inexhaustible source of energy on a human scale. The conversion of solar energy into electricity can be achieved through two distinct technologies: photovoltaic (PV) panels and concentrated solar power (CSP) plants. Among CSP technologies, solar tower power (STP) plants are better at turning concentrated solar energy into high-temperature for power generation. In STP pants, the receiver is the mean element. It absorbs and converts concentrated solar energy into thermal energy. It has a significant impact on the energy performance of the STP plants.

The focus of our work was on optimising the configuration of the heliostats field, the height and the tilt angle of the solar receiver of a 30 kWe STP plant for electricity generation in the Sahelian zone. In addition, we investigated the feasibility of integrating a three-dimensional compound parabolic concentrator (3D-CPC) into existing STPs to increase the concentration rate of solar rays in the receiver.

The results obtained revealed that the solar field consists of 175 heliostats of 2 m2 surface and 1.5 m height distributed in a staggered radial configuration. The use of a 3D-CPC increases the concentration ratio and, consequently improve the thermal performance of the receiver. The 35° truncated 3D-CPC increases the solar concentration in the receiver by a factor of 4.90, with an optical efficiency of 82.15%. The thermal efficiency is 37.92% and the solar-electric efficiency is 26.97% for an air outlet temperature of the receiver of 1,301 K.