Home Battery Payback Calculator — US

A battery pays for itself on arbitrage only when a unit you store is worth more than a unit you export. In the United States that difference is not a national number — it is a state policy, and the states disagree with each other completely.

So this page fills in the half it can: EIA’s national residential rate of 18.44 cents. The export credit and the battery price stay blank until you supply them, and the result box stays quiet until you do. A payback year computed from a made-up export rate would be the most confident-looking wrong number on the site.

Every field below is editable, and every default carries its source and date on the field itself — the defaults are a starting point, not a claim about your bill. We sell no hardware and take no installer commission; see how we verify.

6 fields on this page ship blank, on purpose

No source we can cite publishes these figures for US, so the fields start empty rather than pre-filled with something plausible. The calculator prints no result until you supply your own.

  • What one exported unit is worth ($/kWh) — There is no national US export rate, so there is nothing to default to. Compensation is set state by state and increasingly utility by utility: some states still credit an exported unit at the full retail rate (true net metering), others pay an export rate well below retail (California’s NEM 3.0 is the largest example), and a few offer no compensation at all. A single national number would be wrong in most of the country. Look your state up on DSIRE, then type the rate your own utility actually pays.
  • Units per month per installed kW — No figure is printed here for two reasons. NREL publishes the authoritative per-location tool — PVWatts, at pvwatts.nrel.gov — but every NREL host was unreachable from our research session on 9 August 2026, and we do not publish numbers we could not read. It is also the wrong shape for a national default: output per installed kW varies by about half again between the cloudiest and the sunniest states, so a US average would misdescribe most roofs. Run PVWatts for your own address, divide the annual kWh by 12 and by the system kW, and type it in.
  • Battery cost ($ per kWh) — No US source we can cite publishes a residential battery product price per kWh. Berkeley Lab publishes paired PV+storage pricing per kW of PV capacity — a median $5.3/W cash against $3.5/W for stand-alone PV — which is a whole-system installed price, not a battery price, and roughly 90% of that paired sample is California. Dividing the one by the other would turn a Californian system premium into a national module price. Type the per-kWh figure from your own quote.
  • Battery modules added to a new system ($ per kWh) — Blank for the same reason as the battery cost above: Berkeley Lab prices paired systems per kW of PV, not storage per kWh, and its paired-pricing sample is overwhelmingly Californian. For scale while you get a quote, its median residential battery in 2024 was 13.5 kWh at a 2-hour duration.
  • Price of one panel ($) — US residential solar is sold as an installed system, not as panels — the per-watt prices published for this market are whole-system prices including labour, inverters, permitting and margin. There is no verified national retail price for a single module, and quoting a distributor or marketplace listing as one would misstate what an American buyer actually pays. Use the installed cost per kW above instead.
  • Usable kWh per panel per day — Follows directly from the generation figure above, which we could not source because every NREL host was unreachable on 9 August 2026. Run PVWatts for your own address with your panel count, then divide the daily kWh by the number of panels.

No result yet — the battery price, your tariff or the export credit has no published figure for this market, so there is nothing to calculate from until you type your own. That is deliberate: a number we invented would look exactly like a number we verified.

How this calculator works — the actual arithmetic

  1. Daily saving = battery kWh × 0.8 usable × (your import rate − your export credit). Storing a unit is only worth the gap between what importing costs and what exporting earns.
  2. Payback years = battery kWh × price per kWh ÷ (daily saving × 365).
  3. The import rate is pre-filled at EIA’s 18.44 cent US residential average for May 2026. The export credit is NOT, because the US has no national one — it is set state by state and often utility by utility.
  4. The battery price is also blank. Berkeley Lab publishes paired PV+storage pricing per kW of PV, not a battery price per kWh, and about 90% of that sample is California.

Why there is no worked example on this page

No worked example, because two of the three inputs have no US default. The export credit is state law — full-retail net metering in some states, an export rate well below retail in others, nothing in a few — and no battery price per kWh is published nationally.

What the arithmetic does tell you without either: where your state credits exports at the full retail rate, the gap is zero and no battery pays back on arbitrage at any price. Establish which regime you are in first — net metering, explained — and only then ask what storage costs.

Sources for this market’s defaults

What this calculator does not know

  • Arbitrage only. Backup value during an outage, which is why most US batteries are actually bought, is not money this sum can see.
  • Assumes the battery cycles fully every day. Real cycling depends on your load shape and your solar.
  • No degradation curve. A battery at year ten stores less than at year one.
  • Export rules change, and have changed sharply in the largest state. A payback built on today’s rate assumes it holds.

Frequently asked

Does a home battery pay for itself in the US?

It depends almost entirely on your state. Where exports are still credited at the full retail rate, storing a unit and exporting it are worth the same and a battery does not pay for itself on arbitrage at all — the case for it is backup. Where the export rate is well below retail, as under California’s NEM 3.0, the gap is what the battery earns, and payback becomes a real calculation.

How much does a home battery cost per kWh in the US?

We do not publish a figure, because no national source does. Berkeley Lab reports installed prices for paired solar-plus-storage systems per kW of PV capacity — a median $5.3 per watt against $3.5 for solar alone in 2024 — but that is a whole-system price, disproportionately Californian, and dividing it out would invent a module price. Its median residential battery that year was 13.5 kWh at a two-hour duration.

What is the export credit where I live?

Look it up on DSIRE, which tracks net metering and net billing rules by state. That single number decides whether this calculator prints a payback at all, which is why it is the one field we refuse to guess at.

Is 0.8 usable capacity realistic?

It is a reasonable round figure for lithium iron phosphate storage, allowing for depth-of-discharge limits and round-trip losses. Manufacturers publish their own usable capacity and round-trip efficiency; if yours differs, the payback scales directly with it.

Guides that explain the numbers

What drives US battery cost

Why there is no single national price per kWh.

How many batteries you need

Sizing storage to a load rather than to a roof.

Adding a battery to existing solar

The retrofit case, which prices differently.

Run these next

Net metering vs net billing calculator

What self-consumption is worth against export, once you know your state’s rules. Two inputs are yours; the import rate is EIA’s.

Solar system size calculator

Turn your monthly kWh into a kW system size and a cost band built on Berkeley Lab’s medians. Bring one number: what a kW produces on your roof.

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