Definitions

The term “qualified solar electric property expenditure” means an expenditure for property which uses solar energy to generate electricity for use in a dwelling unit located in the United States and used as a residence by the taxpayer.

The term “qualified fuel cell property expenditure” means an expenditure for qualified fuel cell property (as defined in section 48(c)(1), without regard to subparagraph (D) thereof) installed on or in connection with a dwelling unit located in the United States and used as a principal residence (within the meaning of section 121) by the taxpayer.

The term “qualified small wind energy property expenditure” means an expenditure for property which uses a wind turbine to generate electricity for use in connection with a dwelling unit located in the United States and used as a residence by the taxpayer.

(A) In general The term “qualified geothermal heat pump property expenditure” means an expenditure for qualified geothermal heat pump property installed on or in connection with a dwelling unit located in the United States and used as a residence by the taxpayer.

(B) Qualified geothermal heat pump property The term “qualified geothermal heat pump property” means any equipment which— (i) uses the ground or ground water as a thermal energy source to heat the dwelling unit referred to in subparagraph (A) or as a thermal energy sink to cool such dwelling unit, and (ii) meets the requirements of the Energy Star program which are in effect at the time that the expenditure for such equipment is made.

The term “qualified battery storage technology expenditure” means an expenditure for battery storage technology which—

(A) is installed in connection with a dwelling unit located in the United States and used as a residence by the taxpayer, and

(B) has a capacity of not less than 3 kilowatt hours.