Development of non-imaging Fresnel lens and sun-tracking device

300x condensed light, flat and half-dome non-imaging Fresnel lenses were designed and prototypes were built, and satisfactory performances with condensing efficiencies of 77.3% for the flat type and 81.5% for the half-dome type were verified. In addition, further examination was made on lens material strength and weather resistance to verify that the present material meets the required performance. A 2-axis sun tracking apparatus was developed, and was put into operation. Its excellent tracking ability was verified by yielding excellent results in all three tracking performance evaluations. Apparatus evaluation concurrently began with the operation of the 2-axis sun tracking apparatus.