Heat Pumps are a recent more efficient heating technology that uses the reverse refrigeration cycle to harness heat from outside for hot water and heating. Heat pumps are considered a green heating system as it uses about a quarter of the energy of traditional boilers to produce hot water. Geothermal ground-source, water-source, and air-source heat pumps are commonly used with other systems such as solar heating systems to further reduce energy consumption. Heat pumps are rated by its coefficient of performance (COP) and using Kaori’s high performance BPHEs can keep your COP high and your cost low.