Does charging and discharging wear out a home battery?
A little, with every cycle, and with time whether it is used or not. Planned to the prices, a 9.5 kWh battery did about 200 to 450 full cycles a year in our runs, against 124 left to itself. Orza counts 1p a kWh for wear.
What these figures rest on: 34 days, 3 September to 7 October 2026, from one real 27.1 kWh home and two London households’ real smart meter readings with a modelled 9.5 kWh battery, on the prices Octopus published, scaled to a year. The warranty limits are worked examples, not any maker’s terms. How Orza is tested.
The tariff decides how many cycles a battery does.
A full cycle is the battery’s whole capacity out once, whether in one go or in pieces. A planned battery cycles more because it also fills when power is cheap and empties when it is dear or pays most to sell.
Full cycles a year, two homes with 9.5 kWh, planned
- Left to itself: 124It only stores spare sun, so in autumn it has little to do.
- Agile or Go, nothing for export: 201 to 223Filled when power is cheap and used in the house.
- Flux: 350 to 370Flux pays most for export from 4pm to 7pm, so the battery also sells.
- Agile with export paid: 400 to 452Agile Outgoing or Outgoing Octopus’s fixed rate.
- Go with Outgoing Octopus: 603 to 626Filled at Go’s night rate and sold at the fixed export rate, almost every night.
Orza only cycles your battery when a trade beats the 1p a kWh it counts for wear.
Free, with no card: an email and a password, and you look round an example home first. Connect your battery through its maker’s cloud when you’re ready, or never. It starts in Monitor only, and nothing is sent to it until you choose.
Turn your warranty into cycles a day.
A battery warranty usually promises a share of the battery’s capacity for a number of years, and may also set a limit on the energy that passes through it, whichever comes first. The limit is the one to check against how hard your battery works.
- Divide the limit by the yearsA limit given in MWh for each kWh of capacity is a number of full cycles: 10 MWh a kWh is 10,000. Over a 10 year warranty that is 2.7 full cycles a day. A limit of 3 MWh a kWh is 3,000 cycles, 0.8 a day.
- Then compare it with your tariffAt 450 full cycles a year, ten years is 4,500 cycles. At 626, it is 6,260. Left to itself, 1,240.
- Every maker sets its ownThe warranty or the datasheet gives the years, the share of capacity it promises to keep, and any limit on energy through the battery. Read yours before deciding how hard to work it.
Full cycles a year: two London homes’ real usage (Low Carbon London) with a modelled 9.5 kWh battery and about 4 kWp of panels, planned on 34 days of real prices and weather from 3 September to 7 October 2026, scaled to a year. Autumn days, so a guide, not a forecast. Planned as Orza plans today, with 1p counted for each kWh out.
A trade is only worth it if it earns more than the wear.
The wear on a kWh out of the battery is roughly its price over the energy it will put out in its life: the price, divided by its capacity times its cycles. The cycles cost you only if they are what ends its life before age does.
The clearest case: Go with Outgoing Octopus
- Fill at Go’s night rate, sell at 12pOnce the battery’s losses going in and out are counted, a few pence a kWh is left.
- £109 to £119 a year, for about 400 more cyclesTrading every night against not, on the two 9.5 kWh homes: about 27p a cycle, or about 3p for each kWh out.
- Worth it if your battery’s wear is under about 3p a kWhWhich depends on what you paid for it, its size, and how many cycles it is good for.
Orza counts 1p of wear for every kWh out of your battery.
So it never fills and empties the battery for a gain smaller than that 1p. The 1p is an allowance Orza sets, not a measurement of your battery: its real wear depends on what it cost, its chemistry and its warranty. We tried 0p, 0.5p, 1p, 2p, 4p and 6p on a real 27.1 kWh home and the two 9.5 kWh homes, on six tariffs.
What each step gave up, against 0p
- 1p: at most £5 a year on any tariffAnd up to 22 fewer full cycles a year on the 9.5 kWh homes, most where export pays by the half hour.
- 2p: up to £14 a year12 to 53 fewer cycles a year on the 9.5 kWh homes where prices invite trading.
- 4p: £108 to £284 a year on Go with fixed exportThe night trade stops, for 357 to 420 fewer cycles a year.
Before you worry about the cycles.
What changes the answer for your battery.
All our guidesGet more from your battery
How Orza is tested
Does charging from the grid wear a battery out faster?
The battery doesn’t know where a kWh came from. Filling from the grid adds cycles only on the days the battery would not have filled from the sun. In our runs, planned on tariffs with nothing paid for export, a 9.5 kWh battery did 201 to 223 full cycles a year against 124 left to itself.
How many cycles does a home battery last?
Its maker says, in the warranty or the datasheet, as a number of cycles or as energy through it. A limit of 10 MWh for each kWh of capacity would be 10,000 full cycles. Check yours, and whether it counts years or energy first.
Is one cycle a day too many?
One a day is 3,650 in ten years. Set that against your warranty’s limit: a limit of 10 MWh a kWh would allow 2.7 a day over ten years, and 3 MWh a kWh 0.8 a day.
Does the wear change how long a battery takes to pay back?
A little: a battery holds a little less each year, so later years save a little less. How long a battery takes to pay for itself.
What does Orza cost?
Nothing right now: everything is free while we spread the word, and no card is needed to join. Paid tiers will come later, and there will always be a free version.
Worked when a trade beats the 1p, and left alone when it doesn’t.
Free, with no card. Look round an example home first, and connect your battery when you’re ready.