8. This regulation applies if the plant is a heat pump and complies with all of the following requirements—
(a)it generates heat using naturally occurring energy stored in the form of heat from one of the following sources of energy—
(i)the ground other than naturally occurring energy located and extracted from at least 500 metres below the surface of solid earth;
(ii)surface water;
(b)in the case of a heat pump with an installation capacity of 45kWth or less, regulation 13 applies;
(c)it has a coefficient of performance of at least 2.9.