High-efficiency photovoltaic-thermoelectric hybrid energy harvesting system based on functionally multiplexed intelligent thermal management

A photovoltaic-thermoelectric hybrid (PV-TEH) system with intelligent thermal management based on the dual functions of thermoelectrics (TEs) is proposed to improve the conversion efficiency of PV cells. The performance of PV cells is highly dependent on the cell temperature, and the temperature gradient can also be used to generate additional electricity. A microcontroller switching circuit is designed using the same thermoelectric module for the functions of thermoelectric generator and thermoelectric cooler (TEG/TEC) to selectively regulate the PV panel temperature according to the heat dissipation requirements. In addition, PWM-based intelligent cooling regulation technology is presented to set up a hybrid energy harvesting and thermal management system with adjustable conversion efficiency. Experimental results show that the conversion efficiency in the proposed hybrid PV-TEH system can reach up to 27.8 % while reducing the temperature of the PV panel by 6℃. Accounting for 23 % of the high-efficiency energy output due to the PV-TEG mode, the time window of the pure power supply is increased to 1.15 h during the 5 h day measurement. In addition, the effective output power of PV is increased from 6 W to 8.1 W in PV-TEC mode. This intelligent energy harvesting and thermal management by employing the TE functionally multiplexed technique can provide a reference for green self-powered electronic equipment.