If you have solar panels and a battery, the tariff you sit on matters almost as much as the kit on your roof. Octopus Flux is one of the most talked-about options for homes like yours, and for good reason. It pays you more for the electricity you sell back at the right time of day, and it lets you buy cheap power overnight. Get the timing right and the same battery that simply stored your spare solar can start earning you money instead.
This guide walks through how the tariff works, who it suits, what the rates look like, and how to squeeze the most value from your setup. We install solar and battery systems across the Midlands every week, so the advice here comes from seeing what actually happens once homeowners switch.
What Is the Octopus Flux Tariff?
Octopus Flux is a time-of-use import and export tariff from Octopus Energy built for homes with solar panels and battery storage. It pairs the price you pay for electricity with the price you get paid for sending it back, and both move depending on the hour of the day. Octopus describes it as a three-rate import and export tariff, and it launched in March 2023 as the supplier’s first time-of-use tariff of this kind.
The clever part is that import and export pricing work together. Cheap power overnight fills your battery, then that stored energy is sold back at a premium during the early evening. Instead of a flat rate for everything, you get rewarded for being flexible about when you draw from the grid and when you give back to it.
How Octopus Flux Works
Electricity moves in two directions between your home and the grid. You import when you take power from the grid, and you export when your solar panels or battery push surplus power back out. Flux puts a different price on each direction at different times.
There are three pricing windows across the day. According to Octopus’s own 02:00–05:00 off-peak and 16:00–19:00 peak windows, the off-peak runs from 2am to 5am with a cheap import rate, the standard rate covers the rest of the day, and the peak window from 4pm to 7pm carries a high export rate. The off-peak window is when you charge up cheaply. The peak window is when selling back pays best. Everything in between sits at the middle rate.
Who the Tariff Is Designed For
Octopus Flux suits homeowners who have solar panels, a battery, and a smart meter. All three matter. The smart meter records your import and export accurately, the solar panels generate free power during daylight, and the battery is what lets you shift energy from cheap times to expensive ones.
Households benefit most when they can stay flexible. If you are home to manage your usage, or happy to set your battery to a schedule, Flux rewards that. It is best for people who like more control and are happy to manually schedule your battery, and it works with any home battery brand. A home with solar but no battery cannot join in any case (see requirements below), because there is nothing to hold cheap energy for the peak window.
Key Features and Characteristics
Flux is defined by four things working together: time-of-use pricing, export incentives, battery-friendly economics, and support for renewable energy.
- Time-of-use pricing means your rate changes by the hour rather than staying fixed, with fixed off-peak and peak windows pinned to UK local time all year round.
- Export incentives mean you are paid more for selling at peak demand.
- Battery-friendly economics mean the gap between the cheap and expensive windows is wide enough to profit from.
- Renewable support means your solar generation feeds straight into the most valuable part of the day. Octopus also matches your consumption with REGO certificates from British renewable generation.
There is also a wider benefit. The tariff nudges households to use and sell power at times that help balance the grid. By encouraging households to shift demand away from the early-evening peak, when the grid is under the most pressure, Flux helps the system as a whole lean less heavily on fossil-fuel back-up during the busiest hours — and you earn more for doing it.
Octopus Flux Import and Export Rates Explained
Your import rate is what you pay for grid electricity, your export rate is what you are paid for sending it back, and both follow the same daily schedule. Rates are highest in the peak window, lowest overnight, and somewhere in the middle the rest of the time.
Rates move depending on the time of day because demand on the grid moves too. Early evening is when most homes switch everything on at once, so power is scarce and valuable. The small hours of the morning are quiet, so power is cheap. Flux passes both ends of that swing on to you.
Octopus Flux Import Rates
You import electricity most cheaply during the off-peak window to keep your costs down. The off-peak import rate runs from 2am to 5am and is the cheapest period to charge your battery, at as little as 7 to 10p per kWh in some regions. This is the moment to fill your battery so you are not buying expensive power later.
Import pricing climbs through the day. The standard daytime rate sits in the middle, and the peak rate between 4pm and 7pm is the most you will pay. As a rough London example, a battery can charge at around 14p per kWh between 2am and 5am, while peak imports cost roughly 34p per kWh. That spread is exactly why scheduling matters.
Octopus Flux Export Rates
Octopus Flux rewards you for exporting at the right moment rather than paying a flat rate for everything. The export rate also follows the three-window pattern, with the evening peak paying far more than any other time.
The peak export window is where the real returns sit. During the 4pm to 7pm peak on weekday evenings, export rates can reach the high twenties to around 30p per kWh depending on region. If your battery is full of cheap overnight power or stored solar, discharging it into the grid across those three hours is the single most profitable thing you can do on this tariff.
Understanding Flux Prices and Tariff Rates
Flux prices are structured around three set bands rather than constant change, and they vary by region. As one published regional example, Octopus Flux export rates have been around 4.99p per kWh from 2am to 5am, 29.32p per kWh from 4pm to 7pm, and 10.11p per kWh at other times. Your own region and the current price cap will shift these figures.
Unlike some half-hourly tariffs, Flux stays steady from day to day. Octopus runs it as a flexible tariff that tracks the price cap, so prices usually only shift when a new cap comes out rather than changing daily. Even so, always check the latest published rates on the Octopus website before you commit, since the numbers above are illustrations rather than a promise.
Solar Panels, Batteries and Smart Meter Requirements
To join Octopus Flux you need solar panels, a smart meter, and a battery, and your system must be certified. Octopus’s eligibility criteria require a solar system and home battery, a smart meter providing half-hourly readings, and an MCS or Flexi-Orb certificate for the installation. A home battery of any brand qualifies. The battery is not optional: without one you cannot store cheap or solar power to sell during the peak window, and you would not meet the eligibility rules in the first place.
Solar Generation and Energy Export
Solar panels generate electricity. They turn daylight into power your home can use straight away, and any surplus can either charge your battery or be exported to the grid.
That generation reduces how much you pull from the grid during daylight hours. Every unit your panels produce is a unit you do not have to buy. Under the 26.11p per kWh average electricity unit rate set by Ofgem for 1 July to 30 September 2026, every unit of solar you use yourself avoids buying grid electricity at roughly that price — which is often where the biggest savings come from, before any export earnings are counted.
Battery Storage Benefits
Batteries store excess energy. Rather than exporting spare solar the moment it is produced, a battery holds it until the time is right to use it or sell it.
This lifts both your self-consumption and your export earnings. You can keep solar back for the evening when the panels have stopped producing, or hold cheap overnight power for the peak export window. Instead of your battery simply acting as storage for excess solar, you can also use it to earn.
Smart Meter Eligibility
Smart meters record energy flows. They measure exactly how much you import and how much you export in half-hourly detail, which is what the tariff is built around — and which is also what the Smart Export Guarantee requires before any supplier can pay you for exported electricity.
Accurate monitoring is essential because your import bill and your export payments both depend on it. Without a smart meter, Octopus cannot see when you drew power or when you sent it back, so the time-of-use pricing simply cannot be applied to your account.
How Octopus Flux Helps Maximise Solar Returns
The way to win on Flux is to control when you charge, when you consume, and when you export. Solar and battery owners who run a consistent daily routine get noticeably more out of the same hardware than those who leave it to chance.
Optimising Energy Usage Patterns
You optimise energy usage patterns by monitoring, managing, and scheduling when your home draws power. The aim is to push heavy use into cheaper windows and keep it out of the expensive 4pm to 7pm slot.
Most solar apps let you set charge and discharge schedules in a few taps. Move high-energy tasks like the washing machine, dishwasher and EV charging outside the peak period, run them overnight or midday, and leave the early evening free for selling back.
Charging and Export Strategies
You charge your battery during cheaper periods and discharge it when prices are high. This is the buy-low, sell-high cycle at the heart of the tariff.
The daily rhythm is straightforward once you picture it. Grid energy comes in overnight, solar comes in during the day, and stored energy goes out during the evening peak. Aim to have your battery as full as possible before 4pm, whether from solar on a bright day or from cheap overnight power when the forecast is poor, then discharge across the peak window.
Reducing Grid Dependence
Renewable generation reduces grid dependence. The more of your own solar you use and store, the less you rely on buying expensive grid power at all.
An integrated solar and battery system supports this by covering more of your day from your own supply. You self-consume during daylight, lean on the battery in the evening, and only top up from the grid at the cheapest times. The result is a home that draws far less from the grid across the year and keeps more money in your pocket.
Savings, Benefits and Potential Drawbacks
On the right setup, Flux can comfortably beat a standard flat electricity tariff, but the size of the gain depends on your generation, your consumption, and how actively you manage things. It is worth being honest about both sides.
Potential Cost Savings
You save through flexible import and export behaviour: buying cheap, using your own solar, and selling at peak. The combination of lower bills and export income is what makes the numbers work.
The figures can be meaningful. In one widely cited model of a home with a 4.9 kWp system and a 5.2 kWh battery on average UK consumption (3,400 kWh a year, exporting around 65% of generation), Flux earned roughly £402 a year from exporting and saved a further £535 a year from importing less grid electricity. Those assumptions matter: a bigger battery, higher generation or a different usage pattern will move the result, so treat it as a guide rather than a guarantee and run your own postcode through the Octopus checker.
Benefits for the Grid and Renewable Energy
The tariff supports grid balancing. By rewarding households for shifting demand and exporting at peak, Flux helps smooth out the evening surge that strains the network.
This benefits more than your own bill. When thousands of homes feed stored energy back during the busiest hours, the grid leans less on expensive, polluting back-up generation. Your battery becomes a small part of a cleaner, steadier energy system, and you are paid for the contribution.
Possible Limitations
The variable pricing model needs some thought before you switch. Because rates change through the day, the value you get is tied to how well you time things, and a home that imports heavily during the peak window could end up paying more, not less.
There is also a hands-on cost. On standard Flux you must schedule the battery yourself, charging roughly 2am–5am and discharging 4pm–7pm; if you would rather not, Intelligent Octopus Flux automates it (see below). And if you have solar only, Flux is not available to you at all — a flat-rate export option such as a 12p Outgoing tariff will serve you better until you add storage.
Octopus Flux vs Agile and Go
Choosing between Flux, Agile, and Go comes down to your kit and how hands-on you want to be. Each tariff has a different pricing philosophy and a different ideal user.
Flux vs Agile
Flux and Agile both vary by time of day, but they behave differently. Flux uses three fixed bands that only move with the price cap, while Agile changes every half-hour in line with the wholesale market, with the next day’s prices published around 4pm. Flux tends to suit solar and battery owners who want predictable windows to schedule around; Agile rewards households who enjoy chasing the cheapest and most lucrative half-hours and do not mind prices shifting daily. If you like a set routine, Flux is easier to live with.
Flux vs Go
Go is built around cheap overnight charging rather than export, so it leans toward EV owners more than solar exporters. Flux pairs cheap off-peak import with a strong peak export rate, which is the combination solar and battery homes want.
The target users differ. Go works well if your main goal is charging a car or battery cheaply overnight. Flux works better if you also want to earn from exporting stored energy during the evening peak. Many solar homes find Flux gives them both a cheap charging window and a paid selling window in one tariff.
Which Tariff Is Best?
The best tariff depends on three things: how much solar you generate, whether you have a battery, and how actively you manage your energy. A solar-plus-battery home that can schedule around set windows is the classic Flux candidate.
A useful rule of thumb: Flux and Intelligent Flux generally earn the most for homes with solar and battery storage because they optimise when you export, while for solar-only homes a flat export rate (such as a 12p Outgoing tariff) is usually the better option — still far above the industry-standard SEG floor, which only has to stay above zero. If you want hands-free running, Intelligent Octopus Flux automates the same idea, though it asks for a battery from an eligible manufacturer.
Eligibility and Switching to Octopus Flux
Moving to Flux is straightforward once your system meets the criteria. The main thing is having the right kit in place and an Octopus account ready to go.
Eligibility Requirements
To qualify you need solar panels, a battery, a smart meter, and a certified installation. Octopus’s Flux eligibility checklist asks for a smart meter giving half-hourly readings, a solar system and home battery, an MCS or Flexi-Orb certificate, and confirmation that your local energy network was notified of the install. You will also need to be an Octopus customer on one of their import tariffs; if you are with another supplier, switching across is part of the process rather than a barrier.
How to Switch
Switching happens through Octopus Energy directly. You sign up to an Octopus import tariff, register your solar and battery system, and apply for Flux through your account.
You will usually need a few details to hand: confirmation of your smart meter, your solar and battery system information, your installation certificate, and the export MPAN (Octopus can apply for one if you do not have it yet). Once that is in place, Octopus sets you up on the time-of-use rates and you can start scheduling your battery to match the windows.
Preparing for Success
Getting the best from Flux means watching how your system performs once you are on it. Use your solar app to monitor generation, consumption, and battery charge, and check that your battery is filling overnight and discharging during the peak window as intended.
It is worth reviewing your import and export rates against your real household needs every so often. Because Flux tracks the price cap, a quick check each time a new cap lands — the next one takes effect on 1 October 2026 — makes sure it is still the right fit. A little attention here is what turns a decent saving into a strong one.
Final Thoughts
Octopus Flux turns a solar and battery system from a passive bill-reducer into something that actively earns. The principle is simple: import when power is cheap, use your own solar through the day, and sell back when the grid pays most between 4pm and 7pm. Do that consistently and the same panels and battery work harder for you.
It is not the right tariff for every home. You need a battery to join at all, and the variable rates reward active management, so a home that cannot shift its usage may do better elsewhere. But for a properly set up solar-plus-battery home that is happy to schedule around the daily windows, Flux is one of the strongest options going.
If you are weighing up solar, a battery, or the right way to get more from a system you already own, our team designs every installation with the tariff in mind from the start. Get the hardware and the tariff working together and the savings look after themselves.