Multiscale modeling and performance analysis of evacuated tube collectors for solar water heaters using diffuse flat reflector

In this paper, the role of using a diffuse flat reflector (DFR) at the back of ETC array to improve heat capture rate is examined. A comprehensive model to estimate the annual energy savings and small-scale technology certificates (STCs) is developed. This model is applied on four major Australian cities representing four Australian solar zones. The tilt and azimuth angles for these four zones are optimized. This optimal setting along with DFR presence could improve the STC entitlements by 14.6% for zone 1; 20.2% for zone 2; 25.9% for zone 3; and 27.9% for zone 4, respectively. This specific-tailored model may increase the annual energy saving up to 95.8% for zone 1; 91.3% for zone 2; 81% for zone 3; and 74% for zone 4 correspondingly.