Solar Hot Water Systems

The typical Florida home has an electric water heater which has two 4,500w electric resistance elements that heat the water stored in a 40-50 gallon tank. Electric resistance heating is the most expensive way to heat water. A solar domestic water heater (DHW) system can reduce your water heating costs by 80% to 90%, annually. Solar hot water systems work using an 80 gallon tank (more hot water available for your family!) and typically only need roof space for 1 solar collector panel. These systems include electric backup, so you will never go without hot water.


Why Switch to Solar

  • Water heating in the average Florida home with an electric water heater accounts for 15% to 30% of the electric bill. Eliminate that with a solar hot water system.
  • The Federal Government offers a 30% tax credit on the installed cost of solar hot water systems. Most local utility companies also offer rebates on solar hot water.
  • On average an installed solar hot water heater will pay for itself in 2-5 years and has a useful life of 20+ years.
  • Solar hot water can put a considerable dent in that large electric bill that most of us live with, while reducing your carbon footprint.
  • Commercial facilities that use hot water can also realize considerable savings by investing in solar hot water.

Direct Open Loop Photovoltaic Operated System features collectors on the roof and a storage tank somewhere below, usually a garage or utility room. A pump is used to circulate the water from the tank to the collectors and back again. The sun’s heat is transferred directly to the water which is circulating through the tank and collector. The direct system with PV option powers the pump instead of electricity, providing hot water even when the power goes out. The direct system is also available without the PV which then relies on the home electrical system to power the pump on sunny days.

Hot water is heated by solar panels on roof

Drainback Systems offer fail-safe freeze protection by removing all water from the collectors and piping when the system is not collecting heat. Each time the pump shuts off, water in the collectors and exposed piping drains into the insulated reservoir tank. Drainback systems circulate fluid-transfer solution through the collectors, then through a heat exchanger where the heat is transferred to the potable water in the solar tank. This system design not only protects the home from freezes, but limits the amount of time the homeowner spends on system maintenance.

Hot water Drainback schematic