The carbon intensity of integrated photovoltaics

To assess the meaningfulness of installing solar photovoltaics in buildings and infrastructures, we consider a carbon intensity (CI) balance perspective and assess whether installing PV at different orientations acts as a net CO2 sink or source, when compared to the same amount of carbon that would be emitted using the local electricity mix. The mean values obtained for the CI of PV in buildings in Europe correspond to 41 gCO2-eq/kWh for a generic rooftop installation. For facades this corresponds to: 51.4, 71, and 214 gCO2-eq/kWh, respectively, for S-, W/E-, and N-facing facades. Notably, the potential to halve these figures by 2030 already exists. These figures are compared to CI mean values for national electricity mixes: 374.5 gCO2-eq/kWh. The results indicate that for most countries the integration of PV in facades (often including N-facing PV façades) would not penalize - and conversely support - a transition towards a carbon-neutral electricity mix.