About Solar Hot Water

A solar hot water system uses the sun to heat air or water for a building’s space and water heating needs, and includes a set of collectors, or panels, that are typically mounted on a building’s roof or on the ground. 

 

A conductive liquid circulates inside of the collectors absorbing the sun’s heat. A controller operates a pump that moves the heated fluid from the collectors to a heat exchanger in a tank. The heat of the circulating fluid transfers to the water in the tank, and this heat is used to heat water for the building, or for a pool. The heat can also be circulated through a radiant floor heating system, or in some applications through central forced-air systems, for space heating. Solar hot water systems do not replace conventional water heaters, but are a supplementary system that can often provide up to 80 percent of a building’s total hot water needs.

Solar hot water systems reduce the use of traditional energy sources, such as oil or electricity, used for water or space heating, thereby reducing fuel costs over time.  Purchasing a solar hot water system generally requires upfront installation and equipment costs, but significant benefits that realized over time. Upfront costs can be offset by the following:

Aside from the value of federal, state and local incentives, the following are important factors that affect the economics of a solar hot water system: 

For more information on incentives that are offered for clean energy projects, please visit MassCEC’s Financing Clean Energy Projects page, or the Database of State Incentives for Renewables and Efficiency (DSIRE)