L. Wang, D. Akamo, X. Liu, K.R. Gluesenkamp, Y. Qiao
Oak Ridge National Laboratory,
United States
Keywords: integrated heat pump, electrification of space heating, phase change material, thermal energy storage, peak demand reduction
Summary:
Electrification of space heating is a very promising method for reducing carbon emissions in the building sector. However, it will significantly increase the demand for the future electric grids. To overcome this challenge, a novel heat pump (HP) integrated with thermal energy storage (TES) was developed. During the off-peak period, TES is charged by the HP with low-cost electricity or renewable power to store cooling or heating energy; during peak time, the stored cooling/heating energy is discharged as the heat source (in winter) or the heat sink (in summer) to run the HP with a higher efficiency. A 2-ton prototype HP was developed. The prototype HP was integrated with a 50-gallon TES tank using phase change material as the energy storage media. A series of lab tests were conducted to characterize the performance of the integrated system operating in both winter and summer modes. The results show that cooling or heating energy was stored and released stably. This proposed system could achieve a higher efficiency than the conventional heat pumps during peak hours. The TES integrated HP has the potential to reduce peak demand and improve electric grid stability. It can also mitigate disturbances to the grid resulting from the growing penetration of intermittent and decentralized renewable generation.