Thermal Load of Direct Steam Generating Absorber Tubes with Large Diameter in Horizontal Linear Fresnel Collectors

Solar thermal power plants are at present the cheapest technology for solar electricity production. Today levelised electricity costs of 15 ct/kWh are achievable at good sites with high levels of direct normal irradiation. Nevertheless further cost reductions are necessary to make solar thermal power plants economically feasible. One possibility for a further cost reduction might be the use of so called Linear Fresnel Collectors in solar thermal power plants. Preliminary cost estimates of this option show that this is a promising potential for cost reduction. The technical feasibility of the linear Fresnel collector has to be checked in theoretical studies and afterwards during operation of a life size prototype under real solar conditions. This paper presents results of preliminary theoretical studies regarding the thermal load of the absorber tube used in a linear Fresnel collector with secondary concentrator