<P> Heat energy naturally transfers from warmer places to colder spaces . However , a heat pump can reverse this process , by absorbing heat from a cold space and releasing it to a warmer one . Heat is not conserved in this process and requires some amount of external energy , such as electricity . In heating , ventilation and air conditioning ( HVAC ) systems , the term heat pump usually refers to vapor - compression refrigeration devices optimized for high efficiency in both directions of thermal energy transfer . These heat pumps can be reversible , and work in either direction to provide heating or cooling to the internal space . </P>
<P> Heat energy naturally transfers from warmer places to colder spaces . However , a heat pump can reverse this process , by absorbing heat from a cold space and releasing it to a warmer one . Heat is not conserved in this process and requires some amount of external energy , such as electricity . In heating , ventilation and air conditioning ( HVAC ) systems , the term heat pump usually refers to vapor - compression refrigeration devices optimized for high efficiency in both directions of thermal energy transfer . These heat pumps can be reversible , and work in either direction to provide heating or cooling to the internal space . </P>
what kind of heating is a heat pump
what kind of heating is a heat pump
thermal energy
thermal energy