How the NEM 3.0 export rate is set

If you want the broad picture of the Net Billing Tariff — what it is, who it applies to, how it compares with NEM 2.0 and what it does to payback — start with our main guide to NEM 3.0 explained for California homeowners. This page goes one level down and answers a narrower question: what actually determines the number you are credited for an exported kilowatt-hour.

Two components decide it: an hourly avoided-cost value that changes by month and hour, and an ACC Plus adder whose size depends on the year you interconnected. Everything below is about those two.

Under the Net Billing Tariff, exports are not credited at the retail rate. They are valued using California’s Avoided Cost Calculator — a model that assigns a value to electricity for each combination of month, hour, and weekday or weekend. The practical consequence is that an exported kilowatt-hour is worth different amounts at different times: least when the grid is saturated with solar in the middle of the day, most during high-demand evening hours. See the CPUC’s net energy metering and net billing program pages.

That shape, rather than any single headline number, is what changed the economics of residential solar in IOU territory. It is also the entire argument for pairing solar with storage: a battery lets you use your own generation during the expensive evening instead of exporting it at midday value.

On top of the avoided-cost value, residential customers of PG&E and SCE receive an additional adder. It is fixed for nine years from the date of interconnection and paid as a separate line item. Crucially, the amount depends on when you interconnected — each annual cohort, or vintage, receives less than the one before. The reduction is 20% of the original adder for each later vintage — a fixed step, not a compounding percentage — so there is no standard adder from the sixth vintage onwards.

Customers who qualify as low income (CARE or FERA) or are in a disadvantaged community receive a larger adder — 3.6¢/kWh for the 2026 vintage. SDG&E residential customers are excluded from the adder entirely.

This vintage structure explains most of the contradictory figures circulating online. A guide quoting 2.2¢ and one quoting 0.88¢ can both be right; they are describing different cohorts. Any export figure without a stated vintage is meaningless. When you read one, including on this page, check which year it applies to.

Why is my export credit so much lower than my rate?

Because they are two different prices. What you pay for imported electricity is a retail rate that carries generation, delivery and programme costs. What you are credited for an export is an avoided-cost value — an estimate of what the grid saved by not having to supply that kilowatt-hour at that hour. The gap between the two is not an error; it is the design of the tariff.

Does the export rate change during the day?

Yes, every hour. The avoided-cost value is defined for each combination of month, hour, and weekday or weekend. It is lowest in the middle of a sunny day, when the grid is saturated with solar, and highest during high-demand evening hours — which is precisely why exporting at midday and importing in the evening is the worst pattern for a solar owner under this tariff.

Which vintage am I?

Your vintage is set by when your system was interconnected, not when you signed, ordered or installed. A system interconnected in 2026 is on the NBT26 vintage and keeps its adder for nine years from that date. If you are unsure, the interconnection date is on your utility documentation.

Does the adder appear separately on the bill?

The ACC Plus adder is paid as a separate line item, so it is visible rather than folded into the export credit. It applies to PG&E and SCE residential customers; SDG&E residential customers are excluded.

What happens after the nine years?

The adder is fixed for nine years from interconnection. The underlying avoided-cost component is a separate matter from the adder and is set by the tariff rather than locked to your account indefinitely — which is why a long-term solar decision should not rest on today’s export value continuing forever.

LADWP measures the difference between what you import and what you export on a bi-directional meter, netting them at your own rate schedule — effectively one-for-one at retail rather than at an hourly avoided-cost value. Surplus becomes a credit that rolls forward to later bills.

There are limits worth knowing. Credits cannot offset the monthly minimum charge or taxes, and any remaining balance is forfeited when the account closes rather than paid out. Because a municipal utility can revise its policy independently of anything the CPUC does, confirm the current terms against LADWP’s own residential rate schedules before relying on them.

You will find articles quoting a single blended export rate — “about six cents” — or an average percentage drop against the old rules. We are not publishing those figures, because a credible number requires the actual avoided-cost tables for a named utility and a named vintage, with the weekday/weekend and daylight-saving handling stated. We have not yet completed that data work.

What we can tell you reliably is the structure: which utilities the tariff covers, that value varies by month and hour, how the vintage-based adder works, and that LADWP operates on a different basis altogether. When we publish an hour-by-hour table, it will name its source file and vintage.

Figures on this page come from the primary sources below and, where noted, from Cali Energy calculations using the stated assumptions. Rates, incentives, and program terms change; each was verified August 11, 2026.

1. CPUC — Net energy metering and net billing
2. SCE — Solar Billing Plan FAQs
3. LADWP — Residential electric rates