A solar water heater can be a good investment for generating hot water for the home. This environmentally friendly process provides heat for household water, space heating and swimming pools by using the sun’s energy to heat air or a fluid which then transfers solar heat directly or indirectly to the home. Over the years, these systems have become more efficient, cost effective and reliable.
Solar Water Heaters
Solar water heaters, or solar thermal systems, use the sun to heat water or a heat-transfer fluid in a collector. The heated water is then retained in a storage tank to be used with a conventional hot water system to provide additional heating when needed. A solar water heater can save money and energy since the fuel source (the sun) is both free and renewable, but a backup traditional heater is almost always necessary for times when demand is high or sunlight is scarce.
Before investing in a solar water heater, there are some factors which should be considered. They may include the economics of a solar water heating system, the amount of sunlight available in the region, and the correct size and energy efficiency of the system to be installed. Local codes, regulations and covenants should also be determined.
The National Renewable Energy Laboratory (NREL) estimates the costs of a solar water system can vary from $2,000to 4,500 depending on the number of residents in the home, the size, type and brand of solar system, geographic location, the roof style where the panels will be mounted and building code requirements. The initial financial outlay for a solar water system is more than the cost of a conventional water heater; however, the costs are competitive when considering the total energy costs over the entire life of the system.
Using solar thermal energy to heat water is cost effective with NREL reporting average water heating bills drop 50 to 80 percent. A typical residential sized solar water heating system reduces the need for conventional water heating by about two-thirds. Since the water heater will be operating less frequently, the solar water system will also extend the conventional heater’s operating life which usually averages between five and 10 years.
Using a solar water heater minimizes the cost of using electricity or fossil fuel to heat the water reducing the associated environmental impacts. NREL reports that replacing an electric water heater with a solar heater can reduce carbon dioxide emissions which trap heat in the atmosphere contributing to the greenhouse effect. Using solar energy in place of nonrenewable fuels may also reduce nitrous oxides and sulfur dioxides, factors which contribute to smog.
To enhance the solar heating system’s operating capacity, it is advised that the majority of hot water be used in the late morning and early afternoon when the solar system is operating at peak performance. Laundry should be done over a period of several days rather than all in one day helping to reduce the length of time the conventional water heater must operate.