Techno-Economical Assessment of a Solar Regenerated Borehole Heat Exchanger Field with PVT Collectors for District Heating
Abstract
Low temperature grids distribute heat with few losses or even gains from the heat source to the decentralized heat pumps in residential districts. This paper discusses the sustainable dimensioning of borehole heat exchanger (BHE) fields by means of system simulations with TRNSYS, focusing on the solar regeneration with PVT collectors. The results show that the combination with PVT can slightly improve the efficiency of well-designed systems. But, solar regeneration enables the reduction of the required BHE length or the number of the boreholes by over 40 %. The techno-economical assessment shows that the combination is economically feasible.