Life-cycle assessment of carbon footprint and energy intensity of thermoelectric generator production for near-room-temperature applications

Abstract

Thermoelectric generators (TEGs) can generate clean electricity from waste heat, but their production also generates energy demand and greenhouse gas (GHG) emissions. In this work, we analyze the time it takes for a TEG to earn back the input energy invested in its manufacturing and the time it takes to offset the associated CO2 emissions. At ΔT = 30◦C, the energy payback time (EPBT) ranges from 2.7 to 8.2 years but can fall to 0.5–1.5 years at ΔT = 70◦C. The global warming potential (GWP) per module ranges from 0.80 to 1.51 kg CO2 equivalent (CO2-equiv). Offsetting this climate burden requires continuous operation at ΔT = 30◦C for 1.2–3.1 years, but the offset period drops to less than 2 months if renewable electricity is used. Our analysis concludes that powder metallurgy synthesis routes and renewable electricity supplies are critical levers to reduce EPBT and CO2 offset times. Optimization of tellurium use and promotion of its recycling can further mitigate non-climate burdens.