Performance analysis of a photovoltaic/thermal system with lunar regolith-based thermal storage for the lunar base

Powering a moon base, especially keeping it warm during the long lunar night, is a big challenge. This paper introduces a photovoltaic/thermal (PV/T) system incorporating regolith thermal storage to solve the challenge of power and heat provision for the lunar base simultaneously. The vacuum of space around the moon helps this system by reducing heat loss. During the moon's daytime, the system not only generates electricity but also captures heat. This stored heat in the regolith is then used at night, reducing the amount of equipment we need to send from Earth. The spectrally selective PV/T panels are designed to absorb a wide range of sunlight (0.3-2.5 mu m) while minimizing heat loss in the infrared range (3-30 mu m). Simulation results of the hybrid solar energy system indicate the average value of the overall efficiency is 45.9%, which relatively elevates 56.1% compared to the PV system. The launch mass of the proposed PV/T system is only 8.4% of a traditional photovoltaic-lithium battery system with the same amount of energy storage. And the total specific energy of the proposed system is 7.3 kWh kg-1, while that of the photovoltaic-lithium battery system is about 0.3 kWh kg-1. In summary, this study proposes an alternative combined heat and electricity supply system for the lunar base, which can greatly reduce the launch mass and free up load for other scientific research equipment.