Is a home battery worth it on Octopus Flux?
Flux pairs import and export: cheap from 02:00 to 05:00, dear from 16:00 to 19:00, and the export rate follows the same shape, so a battery can sell back at the peak. You need solar panels, a home battery and an MCS certificate to join.
The tariff in brief
| Price pattern | Off-peak 02:00–05:00; peak 16:00–19:00 for import and export. |
|---|---|
| Who can get it | Needs solar panels, a home battery and an MCS certificate; import and export are taken together. |
| Octopus product code | FLUX-IMPORT-23-02-14 |
| London unit rates | 17p / 28.1p / 39.3p per kWh |
| London standing charge | 44.4p per day |
Octopus public API, fetched 25 October 2026. Import prices shown with the normal 5% VAT (VAT is off bills from 1 October 2026 to 31 March 2027).
A day on this tariff in London
All 48 half-hours
| Time | p/kWh | Time | p/kWh |
|---|---|---|---|
| 00:00 | 28.1p | 12:00 | 28.1p |
| 00:30 | 28.1p | 12:30 | 28.1p |
| 01:00 | 28.1p | 13:00 | 28.1p |
| 01:30 | 28.1p | 13:30 | 28.1p |
| 02:00 | 17.0p | 14:00 | 28.1p |
| 02:30 | 17.0p | 14:30 | 28.1p |
| 03:00 | 17.0p | 15:00 | 28.1p |
| 03:30 | 17.0p | 15:30 | 28.1p |
| 04:00 | 17.0p | 16:00 | 39.3p |
| 04:30 | 17.0p | 16:30 | 39.3p |
| 05:00 | 28.1p | 17:00 | 39.3p |
| 05:30 | 28.1p | 17:30 | 39.3p |
| 06:00 | 28.1p | 18:00 | 39.3p |
| 06:30 | 28.1p | 18:30 | 39.3p |
| 07:00 | 28.1p | 19:00 | 28.1p |
| 07:30 | 28.1p | 19:30 | 28.1p |
| 08:00 | 28.1p | 20:00 | 28.1p |
| 08:30 | 28.1p | 20:30 | 28.1p |
| 09:00 | 28.1p | 21:00 | 28.1p |
| 09:30 | 28.1p | 21:30 | 28.1p |
| 10:00 | 28.1p | 22:00 | 28.1p |
| 10:30 | 28.1p | 22:30 | 28.1p |
| 11:00 | 28.1p | 23:00 | 28.1p |
| 11:30 | 28.1p | 23:30 | 28.1p |
Flux is the only Octopus tariff here that pays for exports from the battery itself. The figures below include battery export; solar adds more on top.
What a battery saves on Octopus Flux: four modelled homes
London prices, typical-household profiles (Elexon Profile Class 1 shape), battery 95% usable, 90% round trip. “Most to pay” is the 10-year price ceiling with capacity fading to 80%. Flux also needs MCS solar; these homes are modelled without it, so the battery earns from import and battery export only.
| Home | Bill, no battery | 5 kWh saves | 10 kWh saves | 13.5 kWh saves | Most to pay for 10 kWh |
|---|---|---|---|---|---|
| Typical home, 2,500 kWh a year | £901 | £230 | £418 | £550 | £3,803 |
| Home all day, 3,500 kWh | £1,193 | £244 | £432 | £564 | £3,934 |
| Electric car, 2,700 + 2,000 kWh | £1,300 | £233 | £421 | £553 | £3,833 |
| Heat pump, 2,700 + 3,500 kWh | £1,962 | £279 | £467 | £599 | £4,249 |
For comparison, the typical home pays £901 a year on Octopus Flux without a battery; Flexible Octopus in London is 27.9p per kWh.
Octopus Flux in every region
| Region | Standing charge, p/day | Cheapest rate | Dearest rate |
|---|---|---|---|
| A Eastern England | 54.26 | 17p | 39.3p |
| B East Midlands | 53.28 | 16.2p | 37.4p |
| C London | 44.41 | 17p | 39.3p |
| D Merseyside and North Wales | 70.08 | 17.8p | 41.1p |
| E West Midlands | 59.44 | 16.3p | 37.8p |
| F North East England | 63.74 | 16.2p | 37.6p |
| G North West England | 47.09 | 16.9p | 39.1p |
| H Southern England | 49.85 | 16.9p | 39.1p |
| J South East England | 54.82 | 17.2p | 39.7p |
| K South Wales | 57.08 | 16.9p | 39.2p |
| L South West England | 58.30 | 17p | 39.2p |
| M Yorkshire | 63.90 | 16.3p | 37.8p |
| N South and Central Scotland | 64.51 | 16.7p | 38.5p |
| P North Scotland | 58.04 | 16.8p | 38.9p |
Frequently asked questions
Is a home battery worth it on Octopus Flux?
In Fortyeight’s model of a London home, a 10 kWh battery on Octopus Flux saves about £418 a year for a typical 2,500 kWh home and up to £467 for the heavier users modelled. To pay back in 10 years it would need to cost under £4,249 at best. Your own data will differ.
Who can get Octopus Flux?
Needs solar panels, a home battery and an MCS certificate; import and export are taken together.
What are the cheap hours on Octopus Flux?
Off-peak 02:00–05:00; peak 16:00–19:00 for import and export. Times are UK clock time, as published by Octopus in October 2026.
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