Solar Panel Calculator for San Diego, CA
Estimate the cost, savings and payback of solar panels in San Diego, CA, using local NREL sunshine data, California prices and electricity rates.
Your result
Enter your numbers and press the button. Your result appears here.
San Diego gets about 5.71 peak sun hours a day on a south-facing roof, so each kW of panels makes about 1,600 kWh a year. That ranks #23 of the 111 cities on this site. Output peaks in Apr and is lowest in Dec.
Sunshine in San Diego by month
What an 8 kW system makes in San Diego
| Month | Sun hours a day | Output | Bill savings |
|---|---|---|---|
| Jan | 4.39 | 864 kWh | $281 |
| Feb | 4.88 | 872 kWh | $284 |
| Mar | 5.96 | 1,144 kWh | $373 |
| Apr | 6.89 | 1,264 kWh | $412 |
| May | 6.11 | 1,160 kWh | $378 |
| Jun | 6.31 | 1,136 kWh | $370 |
| Jul | 6.77 | 1,256 kWh | $409 |
| Aug | 6.64 | 1,224 kWh | $399 |
| Sep | 6.30 | 1,136 kWh | $370 |
| Oct | 5.44 | 1,032 kWh | $336 |
| Nov | 4.75 | 896 kWh | $292 |
| Dec | 4.08 | 808 kWh | $263 |
| Year | 5.71 | 12,800 kWh | $4,170 |
Savings at 32.58¢ per kWh (California average), with every kWh credited at that price.
Cost and payback by system size
At $2.52 per watt, the California average, before incentives.
| System | Cost | Year 1 savings | Payback | 25-yr gain |
|---|---|---|---|---|
| 4 kW | $10,080 | $2,085 | 4.9 yrs | $39,037 |
| 6 kW | $15,120 | $3,128 | 4.9 yrs | $58,555 |
| 8 kW | $20,160 | $4,170 | 4.9 yrs | $78,074 |
| 10 kW | $25,200 | $5,213 | 4.9 yrs | $97,592 |
| 12 kW | $30,240 | $6,255 | 4.9 yrs | $117,111 |
How many panels you need in San Diego
| Monthly use | System | 400 W panels |
|---|---|---|
| 500 kWh | 3.75 kW | 10 |
| 750 kWh | 5.62 kW | 15 |
| 1,000 kWh | 7.50 kW | 19 |
| 1,500 kWh | 11.25 kW | 29 |
| 2,000 kWh | 15.00 kW | 38 |
Covering 100% of a year's use at 1,600 kWh per kW.
Common questions
Is solar worth it in San Diego?
At local averages an 8 kW system costs about $20,160 before incentives, saves about $4,170 in its first year and pays back in about 4.9 years.
How many peak sun hours does San Diego get?
About 5.71 a day over the year on a south-facing roof at 20°, from 4.1 in Dec to 6.9 in Apr, according to NREL's PVWatts model.
How much does a 1 kW solar system produce in San Diego?
About 1,600 kWh a year, or 133 kWh a month on average.
Is there a federal solar tax credit?
Not for homeowners who buy their system. The 30% Residential Clean Energy Credit ended for systems installed after December 31, 2025.
Sources
- NREL PVWatts V8 API (south-facing, 20° tilt, 14% losses, typical-year weather): https://developer.nlr.gov/docs/solar/pvwatts/v8/
- EnergySage, Solar panel cost by state (updated November 6, 2026): https://www.energysage.com/local-data/solar-panel-cost/
- U.S. EIA, Electric Power Monthly, Table 5.6.B (residential price, Jan–Aug 2026): https://www.eia.gov/electricity/monthly/epm_table_grapher.php?t=epmt_5_6_b