Techno-economic analysis of a photovoltaic-driven R290 chiller with a phase-change-material (PCM) storage tank for refrigeration applications.

This article examines whether the use of electrical or thermal storage is economically feasible for photovoltaic plants supplying power to a cold store. It is assumed that the PV plant does not receive a feed-in tariff for the electricity generated and that the PV plant cannot feed excess electricity into the grid. It is shown that economic operation with storage is possible, but a reduction of the storage costs is necessary. In the case of a storage tank with phase change material and an installed PV peak power of 112 kWp, lower levelized cost of cooling energy (LCCE) can be achieved at specific additional costs for storage below € 44 / kWhth, which corresponds to a required cost reduction of -39%. If a PV peak power of 224 kWp is available this will result in lower LCCE at specific additional costs for storage below € 76 / kWhth, which corresponds to a required cost reduction of -16%. The use of battery storage currently generates higher costs. Lower LCCE for the battery scenario with 112 kWp can only be achieved with additional costs for storage below € 120/kWhel, which corresponds to a necessary cost reduction of -84%. In the battery scenario with 224 kWp, lower LCCE can be achieved below additional costs for storage of € 220/kWhel, which equals a cost reduction of -71%. It can be summarized that both battery and PCM storage allow economic operation for the described cold store if the calculated cost reductions for the individual storage component can be achieved in the near future.