Testing of vertical geothermal heat with solar accumulation

The project's aim has been to investigate and document the possibility of storing excess solar heat in the sub-plot (down to 100 meters) in an energy well, and then use the accumulated heat via a heat pump through the winter season. The goal is to increase the yearly effect factor of a traditional heat pump. A plant consists of: solar panels, heat pumps, energy wells, accumulation tank, measuring equipment, stove with water-chamber, heat exchanger and a heat control unit. The 18 m2 solar collectors have been producing 8.5 MWh. The 5.5 MWh is used directly for hot water and heating the home. The last 3 MWh was sent to the accumulation of energy well. Through the heat pump is retrieved 12.5 MWh of energy well. The compressor and circulationg pumps have all spent 6.0 MWh. This means that the total heat consumption has been 27 MWh. Additionally, the stove delivered 0.7 MWh on the water side and approx. 2.8 MWh on the air side. With a price of 1.82 DKK/KWh we can calculate an annual heating cost of DKK 10.920. The cost of heating the same volume using an oil-based boiler would have costed approx. DKK 26.500. The 27 MWh: 10.920 = ca. 0.40 DKK per KWh.