Do You Need a Battery Under NEM 3.0 in California?
Short answer: no — a battery is not mandatory under NEM 3.0. But on the SCE, PG&E and SDG&E Net Billing Tariff it often improves the economics: midday exports earn a low, time-varying credit, so storing that solar to offset pricey evening power raises your self-consumption. Whether it pays off depends on your rate plan, usage, battery cost, and SGIP eligibility.
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- A battery is not mandatory under NEM 3.0. Solar-only is fully allowed and still cuts your bill by offsetting daytime usage at the retail rate.
- On SCE, PG&E and SDG&E (the Net Billing Tariff), midday exports earn a low, time-varying credit — an illustrative 5–8¢/kWh at common midday hours — so a battery that stores that solar for pricey evening on-peak improves the economics.
- LADWP is different. It’s municipal and runs its own solar rate schedules (not NEM 3.0), so there a battery is mostly a backup decision — confirm the current schedule.
- Backup value is separate from bill economics. A battery can be worth it purely for outage protection even when the bill math is marginal.
- Every payback figure here is an illustrative planning scenario, not a guarantee.
This article answers one question: whether you need a battery at all under NEM 3.0. If you’ve already decided to get one, our other guides go deeper:
- Which battery to buy — capacity, power and chemistry compared.
- How big a battery you need — a sizing calculator.
- Whole-home vs critical-loads backup — the wiring architecture.
- Virtual power plant earnings — getting paid to share stored power.
So — do you actually need one?
No. Nothing in NEM 3.0 forces you to buy a battery, and a well-designed solar-only system is still legal and still saves money. The honest answer is that under the Net Billing Tariff a battery usually improves the economics — but “improves” is not “required.” Whether it’s worth it for you comes down to your utility, your rate plan, when you use power, the battery’s price, and whether you qualify for an incentive.
Two different reasons to add a battery often get blended together, and separating them is the key to a clear decision:
1) Bill economics — using more of your own solar instead of exporting it cheaply. 2) Backup — keeping the lights on during an outage or a Public Safety Power Shutoff. A battery can win on one, both, or neither. This guide is about the first question — the money math under NEM 3.0. We cover the backup side in solar batteries for outages & PSPS.
Why NEM 3.0 changes the battery math
Under the old rules (NEM 2.0), a kilowatt-hour you exported was worth almost the same as one you used. The Net Billing Tariff broke that link.
NEM 3.0 prices imports and exports separately: you buy grid power at the full retail rate, but the credit for power you export is a time-varying avoided-cost value, usually far below retail — an illustrative 5–8¢/kWh at common midday hours (a few late-summer evening hours are worth much more). It is not a kWh-for-kWh bank; there are hundreds of separate hourly export prices across the year. So exporting your midday surplus earns little, while the power you buy back on a summer evening can cost far more — on SCE’s TOU-D-PRIME, for example, roughly 26¢ off-peak vs about 59¢ on-peak.
A battery closes that gap. It stores the midday solar you’d otherwise export for a few cents and lets you use it in the evening instead of buying ~59¢ grid power — raising your self-consumption. Self-consumed solar is worth the full retail rate you avoid, which is several times the midday export credit. That difference is the entire economic case for storage under NEM 3.0. For the full rules, see NEM 3.0 (the Net Billing Tariff) explained.
Is a battery worth it for your situation?
Use the table as a starting point, not a verdict. It maps common situations to whether a battery is likely worth it and why — all illustrative. Your installer should model your actual usage and rate plan before you decide.
| Your situation (utility · usage · backup need) | Battery likely worth it? | Why (illustrative) |
|---|---|---|
| SCE / PG&E / SDG&E, TOU rate, high evening use (AC, EV charging at night), wants backup | Likely yes | Shifts cheap midday solar to offset ~59¢ evening on-peak and adds outage protection — the strongest case. |
| SCE / PG&E / SDG&E, TOU rate, daytime-heavy use (work-from-home, daytime AC, pool pump, midday EV), no backup need | Often marginal | You already self-consume most solar at retail, so there’s less surplus to store — solar-only can pencil out. |
| SCE / PG&E / SDG&E, modest budget, no critical backup need | Optional — can wait | Solar-only still cuts the bill. Add a battery later if your usage, rates, or an incentive change the math. |
| Any IOU, frequent PSPS or medical equipment on-site | Yes — for backup | Here the driver is resilience, not export arbitrage. Value it on keeping power on, separate from bill math. |
| LADWP (municipal), typical usage, no backup need | Usually not for economics | LADWP isn’t on NEM 3.0; its own schedules are generally more favorable, so the self-consumption gain is weaker. Confirm the current schedule. |
| LADWP, wants outage protection | Maybe — for backup | Same as above: buy it for resilience, not export economics. |
Framework based on EnergySage — NEM 3.0 and the CPUC Net Billing Tariff. Illustrative — not a guarantee.
Solar-only vs solar + battery: an illustrative comparison
Here’s how the two options behave for a typical SCE/PG&E/SDG&E home on NEM 3.0. It’s a labeled planning scenario to show the shape of the trade-off — not a quote and not a promise.
| What happens | Solar only | Solar + battery |
|---|---|---|
| Daytime usage | Offset by solar at the retail rate | Offset by solar at the retail rate |
| Midday surplus | Exported for a low, time-varying credit (illustrative 5–8¢) | Stored in the battery for later |
| Evening on-peak (~59¢ on SCE) | Bought from the grid at the on-peak rate | Largely offset by stored solar |
| Grid outage / PSPS | System shuts off — no backup | Backup for selected loads |
| Typical added upfront (before incentives) | — | ~$10,000–$18,000 for the battery |
| SGIP incentive | n/a | May apply if eligible — most budgets waitlisted in 2026; confirm live status |
| Illustrative payback | Bill offset only — longer under NEM 3.0 | Often at least as fast, since more solar offsets pricey evening power — but higher upfront |
Payback direction per EnergySage — solar under NEM 3. Battery pricing reflects typical California installs before incentives. Every figure is illustrative and depends on your project — an estimate, not a guarantee.
Two 2026 caveats on the battery’s upfront cost. First, the 30% federal tax credit ended December 31, 2025 for owner-bought systems, so a cash or loan buyer gets no federal credit on the battery this year (details here). Second, California’s SGIP rebate can offset a battery, but most budgets are waitlisted in 2026 — check the live status before you count on it.
When solar-only still makes sense
Plenty of homes do fine without a battery. Solar-only tends to pencil out when…
You use power during the day
Work-from-home, daytime AC, a pool pump, or charging an EV at midday means you self-consume solar as it’s made — at the retail rate — so there’s little cheap surplus for a battery to rescue.
Your budget is tight
A battery adds roughly $10,000–$18,000 before incentives. Solar-only still cuts your bill now, and a battery can be added later if the math changes.
You’re on LADWP
Municipal schedules are generally more favorable than the IOU Net Billing Tariff, so the self-consumption advantage of a battery is smaller. Backup may still justify one.
You rarely lose power
If outages and PSPS events are rare where you live, you’re not paying for resilience you won’t use — the decision rests on bill economics alone.
It’s a different question entirely
LADWP is a customer-owned municipal utility and is not governed by the CPUC’s Net Billing Tariff. It runs its own solar rate schedules (generally more favorable than the IOU tariff), so the “store cheap midday exports” logic that drives batteries on SCE/PG&E/SDG&E is weaker here. For an LADWP home, a battery is mostly a backup decision. Always confirm your current schedule — see LADWP net metering in 2026.
Backup value is separate from bill savings
A battery earns its keep two different ways: lowering your bill (self-consumption) and keeping power on in an outage. These don’t have to both win. If you have medical equipment or frequent PSPS events, backup alone can justify a battery even when the bill math is thin. Conversely, don’t buy one expecting midday exports to pay for it — under NEM 3.0 those exports are worth little. Judge economics and resilience on their own merits.
Ask for both scenarios, side by side
A transparent way to settle it: ask your provider to model solar-only and solar + battery using your actual usage and rate plan, with the export credit and evening on-peak priced in. Compare the estimated payback of each, then weigh how much you value backup. Five things move the answer:
- Rate plan — a bigger off-peak-to-on-peak spread makes storage more valuable.
- Usage shape — evening-heavy homes gain more than daytime-heavy ones.
- Battery cost — the installed price after any incentive.
- SGIP eligibility — a rebate can change the math; confirm live status.
- Backup need — PSPS frequency, medical equipment, and how much resilience is worth to you.
Both scenarios are estimates, not guarantees — but seeing them next to each other makes the decision yours, not a sales pitch.
The bottom line
Under NEM 3.0 a battery is optional but often economically sensible — especially on an IOU with a big evening on-peak and evening-heavy usage. It’s less compelling if you use most of your power in daylight, if you’re on LADWP’s more favorable municipal schedules, or if outages are rare. And it’s a clear yes whenever backup matters to you, regardless of the bill math. Still weighing the whole solar decision? Start with is solar still worth it in California?
Cali Energy has installed 2,000+ solar, battery and electrical projects across Los Angeles and the Valley since 2017 (licensed, CSLB #1032379). We’ll model solar-only and solar + battery on your real usage so you can decide on the numbers — not a sales pitch.
Frequently asked
Is a battery required under NEM 3.0?
No. NEM 3.0 (the Net Billing Tariff) doesn’t require a battery, and a solar-only system is fully allowed. It simply changes the economics: because midday exports earn a low, time-varying credit, a battery that stores that solar for the evening usually improves your savings. “Improves” isn’t “required” — solar-only can still cut your bill.
Does a home battery pay for itself under NEM 3.0?
Sometimes, but it’s an estimate, not a guarantee. By shifting cheap midday solar to offset expensive evening on-peak power, a battery raises self-consumption, and EnergySage finds that in some NEM 3.0 scenarios solar-plus-storage can match or beat solar-only payback, while in others the added battery cost lengthens it. The result depends on your rate plan, usage, battery price, and whether you qualify for SGIP — confirm live status before counting on it.
Do I need a battery if I'm on LADWP?
LADWP is a municipal utility and isn’t on NEM 3.0 — it runs its own solar rate schedules, generally more favorable than the IOU tariff, so the export-arbitrage case for a battery is weaker. On LADWP a battery is mostly a backup decision rather than a bill-savings one. Confirm your current schedule; more in LADWP net metering 2026.
Can I add a battery later instead of at install?
Usually yes — many systems can add an AC-coupled battery afterward. Doing it later lets solar-only start saving now and defers the battery cost until the economics or your backup needs change. Adding it at the same time can be more efficient on labor and permitting. Weigh both with your installer; eligibility and timing vary by project.
Which has better payback: solar-only or solar + battery?
Under NEM 3.0, solar + battery can, in some cases, match or beat solar-only payback — because more of your solar offsets pricey evening power instead of earning a low export credit (EnergySage). But it costs more upfront and the result is an illustrative estimate that depends on your usage and rate plan — not a guarantee.
Is backup the same as saving money?
No — they’re separate. Bill savings come from self-consumption; backup is keeping power on during an outage or PSPS. A battery can be worth it for resilience even if the bill math is marginal, and midday exports won’t pay for it under NEM 3.0. Decide each on its own terms. See whole-home vs critical-loads backup for how backup is wired.
Related reading
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Get a free estimatePrepared by Cali Energy, August 2026. This article is for general educational purposes only and is not legal, tax, financial, engineering, or utility advice. Rates, incentives, codes, permit requirements, equipment specifications, prices, and program terms may change; figures and timelines are estimates, not guarantees. Confirm current requirements with the applicable utility, AHJ, program administrator, manufacturer, or a licensed professional. See our Content Disclaimer. Cali Energy · 19201 Parthenia St Unit E, Northridge, CA 91324 · CSLB #1032379 (B, C-10, C-39)