Solar electricity generation - A comparative view of technologies, costs and environmental impact

The implementation of solar power plants in regions of high insolation is a promising option for an environmentally compatible electricity supply strategy. Today, approximately 80% of the solar generated electricity is provided by solar thermal power plants, while 20% is supplied by photovoltaic systems. Decision-makers have the choice among the following solar technologies: (1) parabolic trough; (2) central receiver; (3) paraboloidal dish; (4) solar chimney; (5) solar pond; (6) photovoltaic cells. This article compares present solar electricity technologies from the point of view of system analysis, taking into consideration their performance, costs and environmental impact. The study shows that the different approaches cover a wide range from units of a few Watts to utility-size plants and from isolated to grid-connected systems. It also shows that there is still a need for intense efforts to integrate those technologies into the existing electricity supply scheme. If a continuous development and market introduction is achieved, solar power plants will contribute substantially to the reduction of global CO2-emissions. A practical tool for decision-makers is presented that facilitates a first estimate of the performance and costs of such plants under local conditions. (C) 1997 Elsevier Science Ltd.