Performance analysis of the heat pipe-based thermoelectric generator (HP-TEG) energy system using in-situ resource for heat storage applied to the early-period lunar base

•HP-TEG system using in-situ resource for the lunar base is proposed.•Effects of design parameters on power generation performance are evaluated.•The maximum total power output of the HP-TEG during the whole lunar day is 9.26 MJ.•HP-TEG system has 24.11% higher energy conversion efficiency than CR-TEG at night.