Profitability of Solar Photovoltaic Rooftop Systems in Buildings with Medium Sized Loads

摘要

In Sweden, it is generally most feasible to install solar photovoltaics (PV) primarily for self-consumption, asrnlong as there either is a large enough load when the sun shines or that over-generation is generouslyrncompensated. Currently there are two support schemes for PV: a capital subsidy and a tax rebate for gridrnfeed-ins. However, the latter is not available for systems above 100A, thus making self-consumption highlyrnimportant for these systems. This paper studies the profitability of systems connected to loads fromrn100 to 700 MWh, most of them above 100A. In particular, it compares multi-family buildings to other buildingrntypes. Analyses were based on measured electricity use matched to simulated PV yield and current marketrnconditions. Calculations were conducted with and without consideration of existing roofs. In general, thernsupply points in multi-family buildings had less favorable load profiles than the ones in other buildings, whichrnresulted in lower self-sufficiencies as well as relatively lower profitability and smaller system sizes. Thernsupport schemes turned out to be crucial for the profitability in most cases, but not all. For supply points inrnother building types with loads above 300 MWh profitable systems were found also without a subsidy. Takingrnareas and orientations of existing roofs into consideration drastically decreased the share of profitable systems.