Study on a ground-source heat pump system for greenhouse heating–cooling
One of the important heating criteria of a greenhouse in the countries of the northern hemisphere is the availability of heat, especially in the winter season. Seasonal soil-based energy storage performance is promising among other types of heat storage. However, performance is affected by the length and depth of the well pipes used, which are very expensive for farmers.
Therefore, this study examines the performance of a flat seasonal ground-based energy storage heat pump in a greenhouse. To reduce heat loss from the floor, thick insulation was installed. The soil thermal imbalance ratio was calculated to know the resulting thermal recovery. Based on the results, the seasonal coefficient of performance (COP) of the heat pump for heating and cooling varied between 1.48–2.97 and 1.20–3.45, respectively.
The COPsys heating and cooling were observed to be 1.51 and 1.55, respectively. In other times of the year, except in winter, the system was able to keep the internal temperature at> 16 ° C. Due to the low level of brine input in winter, the average indoor temperature fell to 11 ° C, which indicates a problem with the thermal soil properties. In addition, the proposed system achieved a soil thermal imbalance of 32.76%.
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Dewanto Harjunowibowo, Siddig A. Omer, Saffa B. Riffat, Experimental investigation of a geothermal heat pump system for greenhouse heating and cooling, International Journal of Low-Carbon Technologies, 2021 ;, ctab052, https://doi.org/10.1093/ ijlct / ctab052