Average Home — California — Solar System Calculator
900 kWh/month household in California with high electricity rates. 15 panels, 5.9 kW system. Net cost: $12,390 after IRA 30% ITC. Payback: 3.7 years.
Usage & location
Find on your electricity bill
Panel & battery
15
Panels needed
5.9 kW
System size
$12,390
Net cost (after ITC)
3.7 yrs
Payback period
100% offset$3,321/yr savings5.8 sun hrs/day9,340 lbs CO₂/yr offset
| Monthly usage | 900 kWh |
| Annual usage | 10,800 kWh |
| Peak sun hrs/day | 5.8 hrs |
| System size | 5.93 kW-DC |
| Panels needed | 15 |
| Panel area total | 323 sq ft |
| Annual production | 10,924 kWh |
| Offset | 100% |
| CO₂ offset | 9,340 lbs/yr |
| Equivalent trees | 195 trees/yr |
Average Home — California — full sizing breakdown
900 kWh/month household in California with high electricity rates.
Full cost breakdown with IRA 30% ITC
LBNL 2023 benchmarks. State incentives not included.
Environmental impact
EPA eGRID 0.855 lbs CO₂/kWh.
California solar resource
EIA 2024 electricity rates.
Sources & Standards
- Dobos, A. P. "PVWatts Version 5 Manual." National Renewable Energy Laboratory, NREL/TP-6A20-62641, 2014.PV system output estimation methodology (irradiance, system losses, tilt and azimuth)
- National Renewable Energy Laboratory. "National Solar Radiation Database (NSRDB)."Solar irradiance data underlying production estimates