Design and construction of an extruded, curved, linear focus, Fresnel lens

A program whose objective is to design and fabricate an extruded, curved, linear focus, Fresnel lens for use in a photovoltaic module operating at 10×concentration is described. The extrusion process is the least expensive lens manufacturing process, producing a lens at approximately 10 $/m². A goal of 70% optical transmission was set. When used in a module, the housing sides would be comolded with the lens. This provides the least expensive module design available today. A 7 4inch wide lens has been designed, and tooling has been fabricated. Several trial extrusions have been made, with the best to date giving a 73% transmission. A post-forming tool was designed and fabricated which improves molded tooth profile to within 0.001 in. of the design. The achievement of over 70% transmission has shown that a PV system with an installed AC busbar electricity cost of under 6 cents/kW-h can be produced. A second-generation extruded lens is currently being developed with the goal of 80% transmission and incorporation into a module