A comparison of solar aided power generation (SAPG) and stand-alone concentrating solar power (CSP): A South African case study

Solar aided power generation (SAPG) is the synergy of solar and fossil plant technology, namely combining the environmental benefits of the former and the scale, efficiency and reliability of the latter. Power plant simulations were performed using weather data for Lephalale, South Africa; home to the Matimba and, currently under construction, Medupi coal-fired power stations. A SAPG plant at Lephalale was compared to a stand-alone concentrating solar power (CSP) in a good solar resource area, namely Upington, South Africa. Parabolic trough collector solar fields of equal size were considered for both configurations. The annual electricity generated from solar thermal at the SAPG plant is more than 25% greater than the stand-alone CSP plant. If the cost of SAPG is taken as 72% of the cost of a stand-alone CSP, SAPG is 1.8 times more cost effective than the stand-alone CSP option.