Fig. 5
From: Meeting the demand: geothermal heat supply rates for an urban quarter in Germany
Results of the evaluation of the heat supply rate with and without the coefficient of performance (\(\text {COP} = 4\)) for three different shallow geothermal systems: horizontal ground source heat pump (hGSHP), vertical ground source heat pump (vGSHP) and groundwater heat pump (GWHP); a presents the area for collector installation; b shows the maximum number n of BHE (\(\textit{n} = 974\)) with a 10-m BHE spacing; c displays the temperature plumes for the 1-K, 2-K and 3-K isotherms (T1, T2, T3 plume) and the cross section used for the energy flow approach. The bar diagram shows the heat supply rate before and after refurbishment for the nine scenarios (Fig. 4). The latter considers a restriction of the drilling depth (RDD, no RDD), optional groundwater flow (GW) and the two different approaches for the GWHP system: energy flow and thermal plume approach