Decarbonizing Industrial Heat – A Comparison of Embodied Carbon for PV and Enclosed Parabolic Trough Systems

Abstract

Heat accounts for more than half the world’s energy use. The largest user of heat is industry, and the pressure to decarbonize is high. Tendencies to “electrify everything” are seen everywhere, but electric energy is expensive for medium and high-temperature heat generation compared to burning natural gas. Moreover, electric grids are on average still characterized by significant greenhouse gas emissions per kilowatt-hour. But how about PV behind-the-meter, being cost-efficient and well-established in generating electricity? Is PV also the solution for the provision of industrial process heat? To answer this, we investigate the specific embodied carbon for heat production, comparing a PV system with GlassPoint’s enclosed trough concentrated solar thermal system (CST). We exemplarily analyze the case of an industrial process heat consumer in a sunny region to show the difference in embodied carbon, land use, and also give some cost indications. Our results show that this is not the case: Compared to enclosed parabolic trough collectors, PV is characterized by significantly higher embodied carbon values and needs about three times the land and corresponding structures to generate a given amount of heat.