Net Billing vs Net Metering for Batteries: 2026
Net billing vs net metering for batteries in 2026: how export rates work, why batteries do the arbitrage now, and sizing storage for self-consumption.
10 MIN READ · UPDATED 2026-09-20
Key takeaways
- Under net billing, solar exports earn a low avoided-cost credit while imports cost full retail — a battery converts would-be cheap exports into valuable avoided imports, capturing the spread daily.
- Net metering made batteries optional; net billing makes them the economic core of a solar investment, with time-of-use rates amplifying the arbitrage further.
- Size storage for self-consumption: cover the high-rate evening window first, size continuous power (kW) for simultaneous loads, and stop before diminishing returns set in past your export volume.
- If you are grandfathered on legacy net metering, confirm the expiration terms in writing and whether adding storage affects them — then size for the post-grandfathering tariff.
- Model economics with your actual utility rates and measured usage as a range, never a guaranteed payback — and confirm permits, inspections, and interconnection in every quote.
For two decades, the economics of home solar rested on a simple deal: your utility bought your surplus electricity at roughly the price it sold you power. That deal — net metering — is disappearing across America, replaced by net billing, where your exports earn a fraction of the retail rate. For solar owners, the change stings. For battery owners, it is an invitation: a battery lets you stop selling cheap and start consuming your own solar at full retail value, doing the arbitrage that the old net metering rules used to do for you.
This guide explains net billing vs net metering for battery storage in plain terms: how each rate structure works, the math of why batteries became the economic core of solar under net billing, how to size storage for self-consumption rather than export, and how time-of-use rates layer on top. If your utility has moved — or is moving — to net billing, this is the single most important concept in your energy economics.
Net metering: the deal that built residential solar
Under traditional net metering, your meter effectively runs backward. Every kilowatt-hour your solar panels export to the grid earns you a credit at or near the full retail electricity rate — the same rate you pay when you import. At the end of the billing period, imports and exports net out, and you pay only for the difference. The grid functioned as a free, infinite battery: overproduce at noon, draw it back at 8 p.m., settle up at retail.
That deal made solar math simple and batteries optional. Without storage, a solar-only home could still zero out most of its bill, because the timing mismatch between midday production and evening consumption did not matter financially. Utilities, for their part, increasingly argued that net metering shifted grid costs onto non-solar customers — whatever you think of that argument, it won in state after state, which is why net billing is now the direction of travel.
Net billing: exports at wholesale, imports at retail
Under net billing, your exports are credited at a lower rate — often described as an avoided-cost or wholesale-ish rate — while the power you import still costs the full retail rate. The spread between the two is the whole game. If your utility credits exports at, say, a few cents per kWh while charging you twenty-plus cents for imports, every kilowatt-hour you export instead of consuming yourself leaves most of its value on the table.
The exact export rate varies enormously by utility and state: some net billing tariffs credit exports at a published avoided-cost rate that changes over time, others use time-varying export values. The common thread is that the rate is well below retail. Check your utility’s current tariff — not a blog post from two years ago — because export values are revised regularly, and the trend has been downward in most markets that adopted net billing.
Why batteries now do the arbitrage solar used to do
Here is the central insight: under net metering, the rate structure did your arbitrage — it valued your noon surplus at evening prices. Under net billing, nothing does that for you except a battery. A battery charged from your midday solar surplus and discharged into your evening loads converts would-be exports (worth a few cents) into avoided imports (worth the full retail rate). The value of each stored kilowatt-hour is roughly the spread between your retail import rate and your export credit rate, multiplied across every day of the year.
Time-of-use rates amplify this. Many utilities pair net billing with time-of-use pricing, where evening peak rates run far above midday or overnight rates. A battery can then do double duty: first, it soaks up solar surplus that would otherwise export cheaply; second, it can charge from the grid during the cheapest overnight window and discharge through the expensive evening peak. The wider the spread between your cheapest charge window and your most expensive consumption window, the harder the battery works for you.
This is why, in net billing states, batteries changed from an optional resilience purchase into the economic engine of the solar investment. The solar array generates the value; the battery captures it.
Sizing batteries for self-consumption
Sizing for a net billing world is a different exercise from sizing for backup. Backup sizing asks: what must stay on during an outage, and for how long? Self-consumption sizing asks: how much of my solar surplus currently exports, and how much evening and overnight load could stored energy displace?
The practical method starts with data. Pull twelve months of interval usage data from your utility — most utilities provide hourly data through their online portal — and look at two numbers: your average daily solar export under the current setup, and your average evening and overnight consumption (roughly 4 p.m. to 7 a.m.). A battery sized to cover the smaller of those two figures captures most of the available arbitrage; sizing far beyond it buys storage for surplus you do not have.
A few sizing rules of thumb, to be refined with your installer’s modeling:
- Start with the evening peak window. In most homes, the highest-value storage covers the 4–9 p.m. peak, when rates are highest and solar has faded. Size usable capacity (kWh) to carry your typical evening loads through that window.
- Do not oversize for the export tail. Once the battery covers evening consumption, additional capacity only earns the thin export rate — a poor return. Diminishing returns arrive fast past the self-consumption point.
- Size power (kW) for simultaneity. The battery’s continuous output must carry your overlapping evening loads — cooking, laundry, air conditioning — or the system will not deliver the savings you modeled. kW first, then kWh.
- Leave headroom for rate changes. Export rates and time-of-use windows change; a system with modest expansion room (or a pre-wired expansion path) adapts better than one sized to the decimal point of today’s tariff.
Net billing vs net metering battery storage: side-by-side
| Factor | Net metering (legacy) | Net billing (current direction) |
|---|---|---|
| Export credit | At or near full retail rate | Lower avoided-cost or wholesale-ish rate |
| Timing of use | Financially irrelevant — meter nets out | Everything — self-consumption beats export |
| Battery’s economic role | Optional; mainly resilience | Central; captures the retail-minus-export spread |
| Optimal system | Solar sized to annual usage | Solar + storage sized to self-consumption |
| Rate risk | Low while grandfathered | Export values revised over time |
What if you are still grandfathered on net metering?
Many utilities grandfathered existing solar customers on legacy net metering for a transition period — often a decade or more from the original install date. If you are grandfathered, your battery economics look different: the arbitrage spread is smaller, because your exports already earn near-retail, so the battery’s financial case rests more on resilience and on time-of-use optimization (if your utility uses TOU rates) than on export capture.
Two things to do while grandfathered. First, confirm your grandfathering terms in writing — the expiration date, and whether adding a battery or expanding the system affects your status. In some tariffs, significant system modifications can reset your grandfathering clock or move you to the new tariff. Second, plan for the post-grandfathering world: a battery bought today for resilience becomes the economic engine of your system the day net billing takes over. Buying the storage before the transition, sized for the future tariff, is often the smart sequencing.
A final grandfathering wrinkle: some utilities apply different export treatment to storage exports than to solar exports, even under legacy tariffs — charging from the grid at night and exporting at day rates can violate program rules designed to prevent pure arbitrage. If your battery strategy includes grid charging, confirm the tariff explicitly allows it. The rules were written for solar; batteries arrived later, and the fine print is still catching up. When in doubt, get the utility’s answer in writing before you program the behavior.
2026 costs and the honest economics
Adding storage to capture the net billing spread is a real investment. For a configuration sized to back up a large home’s essential and comfort loads — which overlaps heavily with the self-consumption sweet spot — installed costs commonly fall in the mid-teens to mid-$20,000s for a single-unit-class installation, climbing into the high $20,000s to mid-$30,000s or more for larger configurations.
Costs are 2026 US market ranges; get itemized local quotes.
Be skeptical of any payback projection presented as fact. The honest calculation: model your actual export rate, your actual time-of-use import rates, and your measured self-consumption with and without the battery, then treat the result as a range, not a promise — because export values and rate structures change. No one can guarantee a payback period, and anyone who does is selling, not advising. On incentives: the federal residential clean energy credit is not available for homeowner-owned battery expenditures after December 31, 2025 — confirm any state or utility incentives with a tax professional, since tax rules change.
Shopping rate plans with a battery in mind
A battery changes which electricity plan is cheapest for you — so shop plans after you understand your storage, not before. On a time-of-use plan, the battery’s job is to erase your consumption from the expensive windows; the wider the peak-to-off-peak spread, the more each stored kilowatt-hour earns. When comparing plans, model your usage with the battery shifting load, not your raw historical usage — a plan that looked expensive for your unshifted profile may be the cheapest once the battery does its work.
Ask your utility three questions most shoppers miss. First, does the utility offer a battery-specific or storage-friendly rate — some do, with super-off-peak charging windows designed for exactly this use. Second, how are exports metered and credited under each candidate plan — plans differ in whether battery exports (as opposed to solar exports) earn credits at all. Third, are there demand charges: a few commercial-style residential tariffs bill on your peak 15-minute draw, and a battery configured for peak-shaving can cut those dramatically — but only if the installer programs it for that job.
Revisit the plan choice annually. Utilities revise time-of-use windows and export values regularly, and the optimal plan for a battery owner shifts with them. The battery is a twenty-year asset; the rate plan is a twelve-month decision. Treat them that way.
Next steps: getting quotes for a net billing world
Bring your utility data to every quote appointment: twelve months of interval usage, your current tariff name, your export credit rate, and your time-of-use windows. Ask each installer the same questions: How much of my solar currently exports, and how much of that would this battery configuration capture? What is the modeled self-consumption rate with and without storage? How does this configuration perform if export rates fall further? Get two to three itemized quotes from licensed, certified installers, compare modeled economics on the same data — not on each bidder’s optimistic assumptions — and confirm permits, inspections, and utility interconnection are in the contract.
Frequently asked questions
Under net metering, your solar exports earn credits at or near the full retail electricity rate, so timing doesn't matter financially. Under net billing, exports earn a lower avoided-cost rate while imports still cost full retail — so self-consuming your solar (via a battery) is worth far more than exporting it. Net billing is the direction most utilities are moving.
Because the battery converts cheap exports into valuable avoided imports. Under net billing, a kilowatt-hour you export might earn a few cents, while the kilowatt-hour you avoid importing at night is worth the full retail rate. The battery captures that spread daily — which is the arbitrage the old net metering rules used to provide automatically.
Size to your self-consumption opportunity: the smaller of your average daily solar export and your evening/overnight consumption. Cover the high-rate evening window first (often 4–9 p.m.), size continuous power (kW) for simultaneous loads, and stop before diminishing returns — capacity beyond your self-consumption only earns the thin export rate.
Your export credit rate, your time-of-use import rates and windows, and your grandfathering terms if you're on legacy net metering — get all three in writing from the utility, not from a sales brochure. Also confirm whether adding or expanding storage affects grandfathered status, since some tariffs reset on system modifications.
It depends on the numbers, which is why honest modeling matters. The battery's value is roughly the retail-minus-export spread times the kilowatt-hours it shifts daily — model it with your actual rates and measured usage, treat the result as a range, and never accept a guaranteed payback period as fact. Resilience value sits on top of the economics.
Confirm your grandfathering expiration date and whether modifications affect it — some tariffs reset on system changes. While grandfathered, the battery's case rests more on resilience and time-of-use optimization. Consider buying storage sized for the post-grandfathering tariff now, so the system is ready the day net billing takes over.