There are two types of solar water heating systems: active, which have circulating pumps and controls, and passive, which don't.
The typical solar water heater is comprised of solar collectors and a well-insulated storage tank.
The solar collector is a network of pipes that gathers the sun's energy, transforms its radiation into heat, and then transfers that heat to either water or a heat-transfer fluid.
The sun's heat is collected through one of three types of solar collectors: Flat-plate Collectors, Integral Collector-Storage Systems (ICS) or "batch systems, and the Evacuated-Tube Solar Collectors. These collectors either preheat water before it enters a storage tank, or, in the case of a heat-transfer fluid, the fluid acts as a heat exchanger and transfers the heat from the fluid to the potable water in the storage tank.
The final component of a solar water heating system is the mounting system. The three most common mounting types are the roof mount, ground mount, and attached or awning mount.
Solar Hot Water Basics
- Solar Hot Water: A Primer
- Solar Hot Water Simplified (pdf)
- Quick Facts: Solar Hot Water
- In Hot Water - Experiences of Solar Hot Water in Arizona
- Economics of Solar Hot Water
- Solar Hot Water Manuals