Increasing the efficiency of conventional LFR technologies: A new CLFR "Etendue-Matched" CSP collector

Abstract

Solar concentrating technologies are seen as an important part of the strategy to increase the production of both renewable electricity and heat. Several technologies have been proved to be technically feasible; commercially Parabolic Through systems (PTR) have been in the lead in installed capacity in new power plants. One promising technology that has a lower investment cost per m2 is the LFR, Linear Fresnel Reflector collector. First demonstration plants in Spain and in the USA, are proving the concept technically, but failing yet to be a generalized choice, since their global efficiency conversion is still low. CLFR technology said to be “Étendue Matched” and designed to take full advantage of ideal non-imaging optics is a very promising alternative. In fact, through a joint optimization of primary and secondary stages of concentration, it is possible to find an answer to this problem, practically doubling the achieved concentration in conventional LFR configurations, substantially reducing optical losses due to shading and blocking and taking advantage of a multi-receiver design (that is what the “C” stands for). The present paper explains the concept and describes the prototype being proposed for demonstration.