cost of solar thermal
Solar thermal (ST) is one of the most cost-effective renewable energy systems. Solar thermal water heating systems collect the sun's energy in the form of thermal or heat energy. The system can save a major portion of your utility bill. This solar thermal system will cost about $4,600 US (with the price decreasing all the time). 2  A solar pool heater, popular and practical, is an open loop system. 3  It's called this because water circulates back into the pool, which is (of course) an open system.