Solar Savings Calculator
How much will solar panels save on your electricity bill? This calculator matches solar output against your home's use hour by hour, then values what you use and what you export. It works with net metering and with lower export rates.
Your solar savings
Your 5 kW system in Los Angeles could save about $1,010 a year, or $80 a month.
Likely yearly saving
- Saved by using solar$500 (39%)
- Credit for exports$510 (39%)
- Bill you still pay$290 (22%)
| Jan | 70 USD |
|---|---|
| Feb | 70 USD |
| Mar | 87 USD |
| Apr | 91 USD |
| May | 96 USD |
| Jun | 94 USD |
| Jul | 96 USD |
| Aug | 96 USD |
| Sep | 88 USD |
| Oct | 82 USD |
| Nov | 72 USD |
| Dec | 66 USD |
Assumptions used
- Yearly solar output
- 9,119 kWh
- Used at home
- 2,789 kWh
- Sent to the grid
- 6,330 kWh
- Still bought
- 4,411 kWh
Why self-use matters
Solar above the use line goes to the grid. Use above the solar line is still bought.
| Point | Solar output | Home use |
|---|---|---|
| 00:00 | 0 | 0.91 |
| 01:00 | 0 | 0.91 |
| 02:00 | 0 | 0.91 |
| 03:00 | 0 | 0.91 |
| 04:00 | 0 | 0.91 |
| 05:00 | 0.07 | 0.91 |
| 06:00 | 0.56 | 0.91 |
| 07:00 | 1.4 | 0.72 |
| 08:00 | 2.24 | 0.72 |
| 09:00 | 2.96 | 0.72 |
| 10:00 | 3.49 | 0.72 |
| 11:00 | 3.75 | 0.72 |
| 12:00 | 3.74 | 0.72 |
| 13:00 | 3.45 | 0.72 |
| 14:00 | 2.91 | 0.72 |
| 15:00 | 2.19 | 0.72 |
| 16:00 | 1.37 | 0.72 |
| 17:00 | 0.54 | 0.72 |
| 18:00 | 0.07 | 0.91 |
| 19:00 | 0 | 0.91 |
| 20:00 | 0 | 0.91 |
| 21:00 | 0 | 0.91 |
| 22:00 | 0 | 0.91 |
| 23:00 | 0 | 0.91 |
What if?
Save this result, change any setting, and compare.
How this is calculated
Solar against your use, hour by hour
For a typical day in each month, we compare solar output with your home's use. Your daytime share sets how much use falls between 7am and 6pm.
Used on site or exported
Solar you use directly saves your full unit rate. The rest goes to the grid. Under net metering, exports offset units you buy that month. Under net billing, exports earn your export rate.
Yearly saving = units used on site × unit rate + export credit
Over the long term
Lifetime savings assume today's prices over 25 years, with panel output falling 0.5% a year. The payback calculator can add price rises.
Worked example: 5 kW in Los Angeles
A home using 600 kWh a month at $0.18 a unit pays about $1,300 a year. A 5 kW system with a 40% daytime share uses about 31% of its solar on site.
With exports paid at $0.08, that saves about $1,010 a year.
How accurate is this?
Solar output stays within 10% of PVGIS for yearly totals at 20 test cities. Use patterns vary much more, so we show savings with a margin of 15%. Typical days also smooth out sunny and cloudy spells.
Common mistakes
- Valuing every solar unit at your full rate when exports earn less
- Forgetting that fixed charges stay on your bill
- Using an average rate instead of your next-unit rate
- Assuming net metering when your area has moved to lower export rates
Limits of this tool
- Your hourly use is estimated from your daytime share, not read from a smart meter
- Time-of-use prices and yearly credit rollover are not modelled
- Savings are estimates and are not guaranteed
What to do next
- See how long these savings take to repay the system in the payback calculator
- Find your true unit rate with the electricity bill calculator
Frequently asked questions
How much do solar panels save per month?
It depends on your rate, your system, and when you use power. In this example, 5 kW in Los Angeles saves about $80 a month.
What is self-consumption?
It is the share of your solar power you use yourself rather than export. Where exports pay less than you pay for power, higher self-consumption means bigger savings.
What is the difference between net metering and net billing?
Net metering credits exports at or near your retail rate. Net billing pays a separate, usually lower, export rate.
Will solar panels eliminate my electricity bill?
Usually not completely. You still buy power at night and in low-sun months, and fixed charges remain unless you leave the grid.