Energy and economic analysis of photovoltaic thermal night cooling and adaptive reset control for ultra-efficient data center immersion cooling

The expanding demand for computing power and escalating associated cooling energy use of data centers is urging information technology industry to increase renewable penetration and opt for efficient cooling technologies. This study proposed a photovoltaic thermal (PVT) -assisted renewable cooling system for immersion cooling data centers to achieve ultra-efficient and renewable cooling. Besides renewable electricity generation, such integration was to utilize night radiative cooling to reduce cooling system power consumption during the daytime. Meanwhile, a cooling water supply temperature reset strategy was developed to better exploit free cooling and reduce pump power. A simulation platform was developed to evaluate the energy and economic performance of the proposed system. Component models were validated against experimental data. Energy and economic analysis of a 21-kW-load case study showed that the cooling system energy consumption was reduced by 42.1 %–64.2 % and revealed a payback period of 2.11–3.75 years, depending on PVT area (10–200 m2) and chilled water tank volume (1–20 m3). The results demonstrated the system's ability to achieve cooling power usage effectiveness below 1.05, significantly advancing data center decarbonization. This integration of PVT night cooling, thermal storage, and adaptive control strategies presents a promising pathway for sustainable and cost-effective cooling in high-density computing environments.