Sunprint
At a glance
IID adopted Net Billing in July 2016, after its net metering program reached its state-mandated cap and closed to new applications. Under Net Billing, IID measures what you take from the grid and what you send to it after your panels have powered whatever the house is using at that moment. You pay for what you take at your normal rate, Schedule D for homes, and each kWh you send out earns 6.98 cents. IID calls that a variable rate, tied to the lowest price it pays for solar on its wholesale contracts, and it can adjust it.
What a kWh of your solar is worth
Prices before state charges and taxes. Sources: IID Schedule D (effective January 1, 2026), rate update page, Schedule DG and Net Billing page, saved November 2026.
A kWh you use yourself is worth more than three times one you export. So the more of your solar the house uses while the sun is up, the faster it pays off: run the pool pump, laundry, dishwasher and pre-cooling in the middle of the day, and size the system to what you actually use.
One month on Net Billing
The kWh your panels make and use in the house never reach the meter, so they never appear on the bill: that's where most of the savings are. Sources: IID's How to Read Your Net Billing Bill, Schedule D (2026) and Net Billing page.
IID's own guide to the Net Billing bill shows both numbers side by side: the kWh you drew from IID, billed at the residential rate, and a line called Customer Excess Generation, credited at 6.98 cents. The bill also lists state-mandated charges, which this example leaves out.
IID's price rises, 2025 to 2028
IID's residential prices, 2025 to 2028
IID had not changed its base rates since 2015 when its board approved a four-step increase in January 2025, starting February 1, 2025. Before that, the residential energy charge was 11.69 cents plus a separate Energy Cost Adjustment; in 2024 IID's residential customers paid 17.91 cents per kWh on average, all charges included, in federal EIA data. The adjustment was set to zero with the new rates, so the 2026 price of 22.30 cents is close to the whole per-kWh charge. Every kWh of solar you use at home avoids that price, and from 2027, 24.38 cents.
The Net Billing rules that shape your system
Sized to your own use
IID doesn't allow oversized systems. You can install enough to cover up to 100% of your energy needs, judged from your last 12 months of use, or an estimate if you don't have 12 months.
Every month stands alone
Extra kWh are credited on that month's bill and aren't carried forward. There's no annual billing or true-up option: charges are due each month.
A two-way meter
IID installs a bi-directional meter that records what you take from the grid and what you send back. It doesn't meter your total solar output.
Automatic enrollment
Once IID approves the interconnection and installs the meter, you're on Net Billing. Systems up to 1,000 kW of solar, wind, biogas, fuel cells or a mix qualify.
Savings and payback for IID homes
| Home | Bill now, a month | System | Saved in year one | Payback at $3/W | At $4/W | At $5/W |
|---|---|---|---|---|---|---|
| Smaller home 8,000 kWh a year | $160 | 4.0 kW | $910 | 12 yrs | 15 yrs | 18 yrs |
| IID's average home 12,840 kWh a year | $250 | 6.4 kW | $1,470 | 12 yrs | 15 yrs | 18 yrs |
| Larger home 18,000 kWh a year | $346 | 9.0 kW | $2,060 | 12 yrs | 15 yrs | 18 yrs |
Sun data for ZIP codes starting 922 (NREL PVWatts), system sized to 85% of yearly use, no battery. Our calculator assumes about 42% of the solar is used at home at 22.30 cents and the rest earns 6.98 cents; the $11.40 customer charge stays. Prices rise 3% a year, the export credit stays flat and panels lose 0.5% a year. IID's average home uses 1,070 kWh a month, by IID's figures.
Payback is the same for every size because the estimate uses one IID price for every kWh. IID has already approved 24.38 cents for 2027, a rise of more than 9%, so the 3% a year in these numbers is on the cautious side. A battery can shorten payback further by holding midday solar for the evening, when it saves 22.30 cents instead of earning 6.98; our battery guide covers the costs.
Who to call at IID about solar
- Before you install (interconnection requirements, forms, first questions): IID's Distributed Interconnection Unit, 1-760-482-3673, [email protected].
- After you install (billing, Net Billing credits): IID Customer Service, 1-800-303-7756, [email protected].
Those are the contacts IID lists on its Net Billing page. Interconnection forms are on IID's rooftop solar pages.
What a free quote call gets you
- One verified local installer
- The installed price for your roof
- Your payback years from that price
- Free, with no obligation
See what solar could save you
About a minute, and no phone number needed. If the number looks good, a free quote call gets you the exact price.
Common questions
How much does IID pay for solar?
6.98 cents per kWh for power your system sends to the grid after your home's own use, credited on each monthly bill. IID calls it a variable rate based on the lowest price it pays for solar on wholesale contracts and can adjust it.
Does IID still have net metering?
Not for new systems. IID closed net metering to new applications in 2016 after reaching its state-mandated cap and started its Net Billing program in July 2016.
Is IID on NEM 3.0?
No. NEM 3.0, the CPUC's Solar Billing Plan, applies to PG&E, SCE and SDG&E. IID runs its own Net Billing program, adopted by its board in 2016.
How big a solar system will IID allow?
Up to 100% of your energy needs. IID doesn't allow oversized systems and uses your previous 12 months of use, or an estimate if you don't have 12 months, to judge the size.
Do IID solar credits roll over?
No. IID credits your excess kWh on that month's bill and doesn't carry kWh forward to later months. There's no annual true-up; charges are due each month.
Is solar worth it with IID?
In our estimate a home using IID's average 1,070 kWh a month pays back a system in about 15 years at $4 a watt. IID's price rises to 24.38 cents in 2027, which makes the solar you use at home worth more.
Related guides
- California solar calculator
- Solar for SMUD customers
- Solar for LADWP customers
- Solar batteries in California
- Average electric bill in California
- Is solar worth it in California?
IID's rates and its Net Billing credit can change; figures here are for 2026. Calculator figures are estimates for typical homes, not a quote for yours. Sources: IID: Net Billing · IID: rates (Schedule D, Schedule DG) · IID: 2025-2028 rate update · IID: Net Billing FAQs · IID: How to Read Your Net Billing Bill · EIA Form 861. Reviewed November 2026.
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