Grant: Applied Research and Development Grants - Level 1

Heating residential or commercial swimming pool with a roof and rack mounted solar collectors is costcompetitive against gas or heat pump pool heaters. It is also the most cost effective use of solar energy in manyclimates. For use when temperatures are above freezing, the solar collectors, the device through which the poolwater is circulated are generally unglazed and made of rubber with built in UV stability. With intrinsicflexibility and stress crack resistance black filled Ethylene Propylene Diene Monomer (EPDM) rubber offersthe best choice of material for solar collectors. For a typical flow rate of 3-7 lpm, the collector tubes aredesigned for a maximum operating pressure of 15-20 psi and come with a warranty of 17-20 years. Amongother factors, the efficiency and design of a solar collector will depend on the wall thickness (reducing wallthickness will increase solar heat transmission). This project examines how far the wall thickness can bereduced to capture the gain from reduced material and shipping costs without foregoing the internal waterpressure withstand stability of the product. Pressure tests will be performed on the actual product assemblyunder pneumatic (leakage) and hydraulic (water pressure) conditions. Appropriate testing procedures will bedeveloped to estimate the design point. Comparative tests on field aged samples will provide additional insightto the long term performance of the collectors.