­­To qualify for a Federal Tax Credit

At least half of the energy generated by the “qualifying property” must come from the sun. Homeowners may only claim spending on the solar water heating system property, not the entire water heating system of the household.

• The credit is not available for expenses for swimming pools or hot tubs.
• The water must be used in the dwelling.
• The system must be certified by the Solar Rating and Certification Corporation (SRCC)

Get more info at Energystar.gov