Savings with a Solar Water Heater System

Solar water heaters provide an efficient means of collecting free energy from the sun. The average household spends 30% of their utility bill on water heating. Minimal operational costs and an extended lifetime of solar water heaters provide for a worthwhile investment for home owners and businesses which utilize a lot of hot water.

The amount of energy savings per year will depend on the amount of solar insolation in the area where the solar water heater is installed, the type of weather around the collectors and the amount of power of the system.

As an example of potential savings with using a solar water heater, below is an analysis for a 300 Liter solar water heater system installed in Huntsville, AL. This system analysis assumes that all hot water is used per day, and that the amount of solar energy gained would have been needed in the case of a standard electric water heater (some households may use more or less)

*Divide kw-hr gained by 0.86 to get total energy consumption for equivalent electrical water heater for calculating savings

As shown in the table above, a solar water heating system easily pays for itself within 4 years. Not only are the cost savings significant, but the possible life of the stainless steel hot water tank justifies the cost of the system on its own. A typical, cheap glass enamel water heater needs replacing about every 7 years. The stainless steel tank is expected to last at least 15 years, and can last 30 years or more if the sacrificial anode rod is replaced on a timely basis. And since the electrical backup element is hardly ever used in a solar water heating system, it hardly ever needs to be replaced, unlike in a traditional electric water heating system.

The Federal Government is also currently paying a 30% rebate on solar water heater installations (cost of product and installation costs). It will currently expire in 2016, however, the government has been extending the rebate on solar water heater systems for a long time and it would not be unlikely for it to extend the credit beyond 2016.

*Maintenance assumes electric water heating element replacements on standard heaters are required once for each tank during its lifespan. Solar water heaters assume 1 gallon of propylene glycol changed every 5 years and the anode rod changed every 3 years.