What is a solar assisted heat pump heating system?
Solar energy is one of the important renewable energy. Hot water could be heated directly by solar collectors without any fuel or electricity consumption. But solar energy has its own defects:
1. Solar energy is a kind of low density energy, and its energy density will be different due to different area or different time.
2. Solar energy is not a continuous and reliable energy. During long term of cloudy or rainy days, the energy supply will stop.
3. Solar energy is an instantaneous energy and can’t be stored without conversion to other type of energy.
So if a heating system with solar energy as the unique heat source, large area of solar collector and big volume hot water tank are both required, the investment for equipment will be high, for a common apartment, the installation space will be also a problem.
As a kind of recognized energy saving equipment, heat pumps can work all-weather within its permitted operation range, and do not need large installation space (air/water heat pump especially). But anyway, heat pumps generate heat at the cost of little electricity. If we combine a heat pump and solar collectors in one heating system, they will compensate mutually
Heating system with heat pump and solar collector in parallel connection:
With the permission of economy and installation space, we recommend increase the area of solar collector reasonably according to the building area, and utilize solar energy first.
If solar energy as the second heat source of a three in one system (heating, cooling, DHW), then:
1. Heat pump is the main heat source of heating and DHW in winter;
2. Solar energy is the main heat source of DHW, heat pump is used for cooling;
3. In spring or autumn, there is no cooling or heating requirement, solar energy is the main heat source for DHW, heat pump is the auxiliary heat source.
In a solar assisted ground source heat pump system, the solar energy is enough in autumn, but there is almost no heating requirement. Besides supplying heat for DHW, the rest solar energy also can be stored in soil and raise the soil temperature before the heating season comes. This will improve the efficiency of heat pump in winter.