Design and experiment of portable thermoelectric power generation system in greenhouse

Greenhouses in remote areas have difficulty to access power. This paper aims to resolve this problem with a new system that can supply electricity to low-power devices such as energy-saving lamps, temperature and humidity monitoring system, digital equipment and other electrical equipment in greenhouses in remote areas. Current power supply to greenhouses uses distributed energy sources from wind and solar, which are not portable and susceptible to environmental changes. Under certain circumstances, power supplied from these systems is insufficient or even fails. As such, there is an increase in developing portable power generation systems. For example, in China, portable multi-purpose photovoltaic power generation system had been developed for agricultural production using remote-control system (programmable logic controller, PLC) to monitor pumping stations. There was also portable multi-power source power generation system to compliment wind power, solar energy and hand-cranked energy generation. Devices to generate power using the difference in temperature between human body and ambient environment exist, which are powerful enough to power LED lights. Another portable device is to generate thermal energy by burning combustibles in the field. All these portable devices have their pros and cons and the purpose of this paper is to present a new portable thermoelectric power generation system. The size of the system was 20 cm × 20 cm × 5 cm weighted 2580 grams, and its energy sources was from combusting biomass. A flat heat pipe was used for thermal conduction. We simulated performance of the system using the ANSYS, and set an experimental platform to test it. The experimental data showed that the highest temperature at the hot end of the system was 270.1℃, the maximum power output was 10.7 W, and the electrical efficiency was 5.73%. The results also revealed that the system had advantages of high hot-end temperature and high thermoelectric efficiency. It can generate electricity under extreme conditions in remote areas. Numerical and experimental analysis of various inputs and outputs indicated that the system is portable, the hot end temperature is high, and the thermoelectric efficiency is high. It provides a baseline for study of portable power generation system. © 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.