Solar water heaters are usually used as a pre heater to conventional water heaters. The solar storage tanks are also of larger volume. The idea of the larger volume is that the solar tank is trying to store at least 1 days hot water usage. The solar tank on a sunny day will slowly heater the volume of hot water required for 24 hours of usage.

Q: “Are solar pool heating system and solar water heating two separate systems or can they be integrated? How are they similar/different?”

A: “The difference between solar pool heating and solar water heating is the temperature they need to achieve. A pool using a plastic solar panel can heat a pool to 90-100 deg/F while a solar water heater needs to heat water to 130-140 deg/F. The solar water heating system needs a solar collector with insulation and a glazing so it can operate at a higher temperature. The systems are not usually integrated as pool water is non-potable vs. domestic water heating, which is potable water. The only similarity is they both use a flat plate collector heated by the sun. However, the solar water heating collector is usually made using a copper absorber rather than plastic.”