An assessment of linear Fresnel lens concentrators for thermal applications

This paper describes an assessment of linear Fresnel lens concentrator technology for use in thermal applications. System performance and cost data for a Fresnel lens concentrator were developed and compared with data for a parabolic trough system. Two thermal applications of these technologies were chosen for the comparison. The first is a water preheat application where energy is transferred from an antifreeze, collector field working fluid to preheat 60 °C water through a heat exchanger. The other application is the generation of saturated steam at 177 °C. Annual performance predictions were generated using a simulation code that includes the effects of both thermal capacitance and heat losses from all piping and system components. Performance was simulated at three different geographic locations. Costs for the collectors were based on documented estimates. Overall costs included all major equipment, site development, and installation. The performance and cost data were combined to arrive at a levelized cost of energy. Based on the performance predictions developed here and on the current documented costs, results indicate that the Fresnel lens systems have a levelized energy cost about one-third less than the parabolic trough systems. This is primarily due to less expensive concentrators.