Life cycle assessment of pasture-based agrivoltaic system (emissions & ecotoxicity).
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Comparison between 4 scenarios show agrivoltaics is superior to conventional practice.
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CO₂ emissions and ecotoxicity quantified for sheep-based agrivoltaic system.
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Integrated production results in 3.9% less emissions and 0.5% less energy demand.
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Agrivoltaics vastly environmentally superior to grid-based electrical production in the US.
Abstract
Solar photovoltaic (PV) growth can be stalled due to social acceptance. Agrivoltaics can improve social acceptance by enabling dual use of land. The most popular type of agrivoltaics in North America is grazing sheep under conventional PV farms. The environmental benefits of this integrated agrivoltaic system are unknown, so this ISO-compliant life cycle assessment study investigates the environmental performance of sheep-based agrivoltaic systems. This study investigated agrivoltaics to produce a combined output of electricity and agricultural goods, in comparison to conventional methods (various electric grid generation mixes in the U.S. and plane pastures) for producing that same quantify of service in both categories. Agrivoltaics is twice as land use efficient as providing sheep and PV services separately. In addition, the global warming potential of agrivoltaics was found to be 3.9% better than conventional PV and sheep grazing separately, and represents two orders of magnitude improvement (280%-894%) over conventional grids in the U.S. and sheep production. Only considering emission reductions from shifting sheep to PV farms for grazing, the U.S. could conserve 5.73E8 kg CO2 eq per year from sheep raising, which is equivalent to removing 117,000 average automobiles from the road. To house the current national 5.2 million domestic sheep in agrivoltaic systems, the U.S. has the potential to expand utility scale PV by a factor of four. The results of this study provide further evidence that agrivoltaic systems are superior to conventional ground-mounted PV systems because they have dual purposes and reduce the environmental impacts associated with producing food and electricity. It is clear that encouraging sheep grazing on all appropriate conventional PV systems is warranted.
