What Does Looking After Home Solar Panels Involve, and What Does It Cost Each Year?
Summary
Very little day-to-day work; most of it is reading the production record. DOE's Federal Energy Management Program (FEMP), writing for federal sites, recommends checking the performance ratio (actual output divided by modeled output) monthly to annually and says 85% should be achievable. NLR puts residential operating and maintenance cost at $30 per kW a year in 2023, or about $237 a year for its 7.9 kW reference system.
Two numbers from the monitoring app
| Indicator | How it is calculated | FEMP benchmark |
|---|---|---|
| Performance ratio | actual production ÷ modeled production | 85% should be achievable |
| Availability | share of time the system was not down | 95% should be achievable |
For New York, PVWatts (south, 20° tilt, 14% losses) models about 141 kWh per kW in July. A 7.9 kW roof would be expected to make about 1,117 kWh that month. If the meter shows 900 kWh, the performance ratio is around 81%. One month can be thrown off by weather. Several months in a row below 85% give you something to look into. FEMP adds that module degradation is "often about 0.5% per year," and that after repeated inverter trips the fix is an electrical inspection, not just turning the system off and on.
What goes into the yearly figure
NLR's Annual Technology Baseline (2024 edition) splits the $30/kW-year into $27 of system-related and $3 of administrative expense. The categories are asset management, insurance, cleaning, vegetation removal, and component failure, and the ATB says not every system needs all of them. Its range runs from $0 to $40/kW a year.
| System size | At $30/kW-yr | At $40/kW-yr |
|---|---|---|
| 5 kW | $150 | $200 |
| 7.9 kW | $237 | $316 |
| 12 kW | $360 | $480 |
On top of that, DOE's system design page expects inverters to be replaced at least once over a 25-year array life. The FTC notes that an owner is responsible for maintenance, or for paying someone to do it, unless the seller's contract covers it; under a lease or PPA the leasing company will probably handle it.
Sources
- U.S. Department of Energy, FEMP — Operate and Maintain an Existing Photovoltaic System (updated 2026-05-20)
- NLR — Annual Technology Baseline 2024, Residential PV
- U.S. Department of Energy — Solar Photovoltaic System Design Basics
- Federal Trade Commission — Solar Power for Your Home
- NLR — PVWatts V8 API (New York, 1 kW, tilt 20°, azimuth 180°, losses 14%; run 2026-09-23)
We have not tested these products. Specs, prices, stock and terms are as published on these pages on the date above and can change; check the manufacturer or retailer before you buy.