Aperture Solar Shows What a Roof Actually Earns

Field notes

The model uses PVGIS SARAH2 yield data averaged across 2005–2020 and selects among named locations, from Glasgow and Dublin to Denver and San Francisco. Its London example assigns a 4 kWp south-facing roof an expected 3,974 kWh annual output, while also showing a 151 kWh weather allowance. The calculation then applies household usage, local currency, electricity rates, and export payments; the site says its battery assessment can reject a purchase when the warranty-period payback does not work.