There are different types of solar water heaters, each with their own advantages and disadvantages. These systems use a solar collector to absorb energy from the sun, then transfer the heat to the water. The most common types of solar water heaters are flat-plate collectors and tube collectors. In both cases, the heated water passes through a tank or exchanger to be used in the home.
The passive solar water heater is the most effective and cost-effective type of solar water heater. This unit can provide up to 80-90% of a household’s water heating needs, and can provide 50% or more of the needed heat for a moderate-climate area. However, it is susceptible to freezing during colder months. In this case, you may want to install drainage in the area to protect the passive water heater. If the passive water heater isn’t enough, you can opt for an active system or a direct open loop system. Active solar water heaters have a pump to circulate the household water through the collectors.
Passive solar water heaters can only heat water, but they can’t power other electrical devices. However, they are more energy-efficient than their active counterparts. A passive solar water heater requires a storage tank, and the size of the tank depends on the number of family members and household size. For a two-person household, you’ll need a two-square-meter-area tank, and for each additional member of the household, an additional 1.5 square-meter-sized tank is needed.
