Octopus Flux for solar and batteries: how it works and what it pays

How Flux works

Flux splits the day into three periods, and the same times apply to what you buy from the grid and what you sell back to it:

• Cheap: 02:00 to 05:00, for filling the battery
• Peak: 16:00 to 19:00, for running the house from the battery and exporting what's left
• Day rate: every other hour

Octopus says the times are UK local time and don't move when the clocks change. On the current South Scotland rates the cheap import rate is about 40% below the day rate and the peak about 40% above it, which is our calculation from Octopus's pricing data.

Flux is a flexible tariff with no exit fee, so the rates can go up or down and Octopus gives notice when they do. To join you need:

• solar panels, which don't have to have been fitted by Octopus
• a home battery
• a smart meter that sends half-hourly readings (a SMETS2, or one of the Secure SMETS1 meters Octopus can connect to)
• an export MPAN, which Octopus can apply for if you don't have one
• the MCS certificate for your installation
• Octopus import and export tariffs already in place

If you're on the old Feed-in Tariff you keep your generation payments, but Octopus says you have to permanently opt out of deemed export payments to be paid for export on Flux.

What it costs and what it pays

Rates vary by region. These are the rates in Octopus's pricing data on 24 October 2026. VAT on home electricity is 0% from 1 October 2026 until 31 March 2027, so there's nothing to add.

For comparison, Outgoing Octopus, the flat export tariff, pays 12p/kWh at any time of day in both regions, which is more than Flux pays for daytime export.

A worked example

Take a winter day with very little solar, a battery with 10 kWh usable, 89% round-trip efficiency (the figure Tesla publishes for the Powerwall 3) and a house that uses 3 kWh between 16:00 and 19:00. On the South Scotland rates:

• filling the battery overnight takes about 11.2 kWh at 15.87p, so £1.78
• 3 kWh runs the house through the peak instead of being bought at 36.70p, which is worth £1.10
• the other 7 kWh is exported at 29.75p, which is £2.08

That's about £3.18 back for £1.78 spent, or roughly £1.40 a day. On a summer day the comparison is different. Five kWh of spare solar exported at midday earns about 55p on Flux, against 60p on Outgoing Octopus, but held in the battery and exported between 16:00 and 19:00 it earns about £1.32 after losses.

Exporting 7 kWh in three hours needs the battery to discharge at about 2.3 kW, so check your inverter's export limit as well. These are our calculations from Octopus's published rates, not an Octopus figure, and they aren't a promise of what you'll earn or pay.

Intelligent Octopus Flux

Intelligent Flux is the version where Octopus controls the battery for you, charging it when electricity is cheap and exporting when the return is highest. Octopus says the import rates are lower than standard Flux.

• On 24 October 2026 Octopus's product page said Intelligent Flux was temporarily unavailable, and also that it's currently only for customers who bought their solar panels and battery from Octopus, so check before you plan around it.
• The battery brands Octopus lists are AlphaESS, Ecoflow, Enphase, Fox ESS, GivEnergy, Hanchu ESS, Huawei, Sigenergy, SolarEdge and SunPower, and Octopus says it can't guarantee compatibility.
• Octopus's FAQ says only one device can be registered per property, so you can't have an EV on Intelligent Flux as well as the battery.
• The FAQ also says the battery keeps a minimum charge of 20%, which Octopus says may vary through the year.

GivEnergy went into administration in April 2026 and the administrator has said hardware warranties won't be honoured, which our home battery guide covers.

Who it suits, and who it doesn't

It suits you if you have solar and a battery that you can schedule, from the battery's own app or something like Home Assistant, and the battery is big enough to run the house through 16:00 to 19:00 with some left to export.

It's unlikely to suit you if:

• you have solar but no battery, as you can't join Flux and a flat export rate pays more for daytime export anyway
• you have a battery but no solar, in which case Agile is the Octopus tariff to look at
• an EV is your main load, as you can only be on one import tariff at a time and Octopus Go gives a longer cheap window overnight