Life cycle greenhouse gas emissions of low-temperature process heat generation by external compound parabolic concentrator (XCPC) solar thermal array

Abstract

New solar-based technologies are currently being developed as prospective low-carbon sources of heat for industry, which require life cycle assessment to determine their actual decarbonization potential relative to current heat sources. We performed the first life cycle assessment of the external compound parabolic concentrator (XCPC) solar array, a novel low-concentration and non-tracking solar thermal technology capable of providing low-to medium-temperature heat (up to 250 °C). Primary data on the materials and performance of the XCPC were used in this analysis. The embodied greenhouse gas (GHG) emissions associated with manufacturing the technology are 92.4 kg CO2eq/m2, cradle-to-gate. The life cycle GHG emissions cradle-to-grave over a 25-year lifetime under conditions in the Central Valley of California are 129.7 kg CO2eq/m2. On the basis of thermal energy delivered, the XCPC has a carbon footprint of 5.8 g CO2eq per kWhth. These results indicate that the XCPC can generate low temperature heat with a carbon footprint 97% lower than natural gas and 98% lower than propane combustion in regions of high solar insolation.