Low-cost Prototyping of the Fresnel Lens Solar Concentrator

Research involving optical elements in the solar industry have been growing intensely, which made rapid and cheap prototyping critical to the success of such optical devices and components. With new technologies being introduced at a breakneck pace, the faster and easier you can prototype, the sooner a research can be concluded and the product can get to market. Depending on the timeline and sourcing requirements, there are several constraining factors that affect optical prototyping, such as a limited budget, geometry constraints, strict deadlines, and material availability.

In this work, linear and spot Fresnel-lens-based solar concentrators, designed by an earlier study of the authors, are prototyped in four methods; two mold-free prototypes made by 3D printing and acrylic CNC machining, and two mold-based prototypes made by acrylic casting and hot embossing. The purpose is to proof the design concept of the Fresnel concentrator and evaluate the best prototyping method for future work. All four lenses are checked for dimensional accuracy in comparison to the design, and then tested under direct sunlight, where each resulting focal irradiance was compared to that achieved by Monte-Carlo Ray Tracing MCRT simulations. A comparative analysis for the cost and fabrication time of each method was presented.