Solar Design-vs-Actual Report

The array was commissioned January 28, 2026. This assessment uses 5 complete month(s) of revenue-grade SolarEdge production (2026-02, 2026-03, 2026-04, 2026-05, 2026-06) plus 2 partial month(s), measured against the unshaded PVGIS design model of 15,648 kWh/yr.

Measured performance is 99.4% of the unshaded model — the array is performing at the design ceiling. The feared tree-shade derate (the competing installer's estimate implied roughly 15% loss, and the planning band assumed 13,500–14,500 kWh/yr) is not materializing in the months observed so far.

Monthly scatter is real weather, not fault: the best month (2026-06) ran +12% against the model and the worst (2026-03) -12%. The production-weighted factor smooths this into one number.

Winter evidence so far comes from month(s) February, March; snow and low-sun shading are partially represented in the factor.

2026 estimate: 14,804 kWh (8,175 measured + adjusted model for the remainder) — below the installer's 15,441 kWh design estimate and above the pre-measurement planning band. That is roughly 100% of the household's ~14,800 kWh/yr recent average consumption. Note 2026 started January 28, so the commissioning year undercounts a full January.

Projected across the 25-year module warranty at 0.25%/yr degradation from the adjusted anchor of 15,556 kWh: 15,517 kWh in 2027, declining to 14,623 kWh in 2050, for a lifetime total of about 376 MWh. These projections re-derive themselves nightly as new months land.