Performance and configuration optimization for a Grid-Connected PV power supply system with Demand-Supply matching in a data center’s centralized Water-Cooling system

Abstract

The cooling system of a data center accounts for a significant part of its energy consumption, and the adoption of solar energy can reduce its power demand from the grid. This paper investigated the optimal configuration of a grid-connected PV power supply system to a data center’s centralized water-cooling system. Firstly, mathematical models for photovoltaic panels and storage batteries were established. Then, two operating strategies were proposed, respectively, for two systems with and without storage batteries, and the supply–demand matching performances were studied. With storage batteries, mismatch problem between electricity generated by photovoltaic panels and electricity consumed by the water-cooling system can be significantly improved. Utilization ratio of electricity generated by photovoltaic panels was increased by up to 27.64 % in the discussed typical days. Annual utilization of electricity generated by photovoltaic panels can also be significantly increased, especially when heat dissipation density is small. Lastly, the optimal configurations were discussed. To reduce carbon emission, number of battery groups were recommended for different heat dissipation density and number of photovoltaic panels. Full life-cycle carbon reduction ranged from 1.77 to 3.71 tCO2/m2 and carbon emissions reduced from 14.23 to 62.14 % as compared with the traditional system. As for the economic performance, the recommended number of photovoltaic panels are 798, 1330 and 1589 for heat dissipation density being 500, 800 and 1100 W/m2, respectively. While the recommended number of batteries was 0 if unit price of batteries is higher than 11.1 ten thousand yuan/group.