Energy performance of a solar tower power plant equipped with a three-dimensional compound parabolic concentrator

The operation of Solar Tower Power (STP) plants requires high solar concentration for power generation. In this study, a Three-Dimensional Compound Parabolic Concentrator (3D-CPC) is used to increase the solar concentration within the receiver and thereby enhancing its thermal performance and, consequently the energy performance of the STP plant. To attain this objective, the solar field is sized for an electrical power of 30 kW. The heliostats are arranged in the field using the radial staggered layout design as seen in PS10 plant. The 3D-CPC is sized, designed and incorporated at the receiver inlet. The solar field is modelled in SolTrace software using an optical model that was developed and validated to gather the average solar flux absorbed by the receiver. In order to ascertain the thermal performance of the receiver, a Computational Fluid Dynamics (CFD) model is created using the volumetric heat source produced from the absorbed solar flux, and then validated to study the heat transfer into the receiver. Subsequently, the energy performance of the STP plant is assessed. The results showed that the solar field consists of 175 heliostats. Each heliostat has a surface area of 2 m2 and a height of 1.5 m. Furthermore, the 3D-CPC enhances solar concentration in the receiver by a factor of 4.90, yielding an optical efficiency of 82.15 %. Additionally, outlet air temperatures of the receiver were higher than those obtained with the conventional Capstone (C30) turbine. For instance, during the summer solstice, the outlet air temperature of the receiver was 1332.77 K and there was a Direct Normal Irradiation (DNI) of 549.64 W/m2, resulting in 39.68 % and 28.32 % thermal and solar-electrical efficiencies, respectively.The obtained results showed that 3D-CPC facilitated a rise in solar concentration into the receiver. Thus, it enhanced the receiver’s thermal performance, thereby improving the overall energy performance of the STP plant.