Direct thermal to electrical energy conversion using very low bandgap TPV cells in a gas-fired furnace system

In this paper, electricity generation using very low bandgap InGaAsSb thermophotovoltaic (TPV) cells whose bandgap is 0.53 eV was investigated in a gas-fired furnace system where thermal radiation was emitted from a metal alloy emitter. The electric output of the InGaAsSb TPV cells was characterized under various operating conditions. The cell short circuit density was measured to be 3.01 A/cm2 at an emitter temperature of 1197 °C. At this emitter temperature, an electric power density of 0.65 W/cm2 was produced by the TPV cells. Experimental results show that direct thermal to electrical energy conversion was achieved in a gas-fired heating furnace system. Such a system could be employed to form a micro-combined heat and power (micro-CHP) process where exhaust heat is utilized for home heating needs. The TPV integrated energy system provides an effective means for primary energy savings.