Assessment of solar-coal hybrid electricity power generating systems

Abstract

Botswana currently depends on electricity generated from coal-based power plant or electricity supplied from the border in South Africa. The country has good reserves of coal and the solar radiation is sufficiently high to make solar thermal attractive for generating electricity. The paper presents two conceptual coal-fired power station designs in which a solar sub-system augments heat to the feed heaters or to the boiler. The thermal and economic analyses showed enhanced system performance which indicates that solar power could be embedded into existing fossil fuel plants or new power stations. Integrating solar energy with existing or new fossil fuel based power plants could reduce the cost of stand-alone solar thermal power stations, reduce CO2 emissions and produce experience necessary to operate a full scale solar thermal electricity generation facility.