Most solar households in the UK are still on a standard variable tariff (SVT) with a basic Smart Export Guarantee arrangement paying 5–7p for every unit they export. That is a problem. Smart tariffs pay two to four times more for the same electricity if you export it at the right time. Choosing the right tariff is one of the easiest ways to improve the return on a solar investment — no hardware required.
Why Your Energy Tariff Matters as a Solar Owner
When you generate more solar electricity than you consume, the surplus is exported to the grid. Your energy supplier is required to pay you for this under the Smart Export Guarantee (SEG). The rate they pay varies enormously:
- Standard SVT SEG rate: 5–7p/kWh (some suppliers). A flat rate paid for every unit exported regardless of when.
- Standard SEG (competitive): 10–15p/kWh. Better dedicated SEG products exist but are still time-blind.
- Smart export tariffs (Octopus Flux peak): ~30p/kWh during peak demand (4pm–7pm).
If you export 2,000 kWh per year on a 5p SEG, you earn £100. On Octopus Flux with strategic exporting during peak hours, the same 2,000 kWh could earn £400+. That is a £300 annual difference for doing nothing different with your solar panels — just switching supplier and tariff.
The catch: the best tariffs for solar owners require a battery. Without storage, you cannot control when you export. Your panels export when they generate, not when prices are high. A battery lets you store solar generation and release it during the 4pm–7pm peak when prices are highest.
The Main Tariff Options in 2026
1. Standard SEG (Any Retailer)
Export rate: 10–15p/kWh flat
Import rate: Standard variable (~24.67p/kWh)
Battery required: No
Best for: Solar-only households without a battery who want simplicity
This is the baseline. Multiple suppliers offer competitive SEG rates: E.ON Next, British Gas, Octopus (standard SEG), and others. Compare rates at Ofgem’s SEG register. No commitment, no smart meter required beyond basic SEG metering. The simplest option if you are not ready for a smart tariff.
2. Octopus Flux
Export rate: ~30p/kWh peak (4pm–7pm); ~15p/kWh standard; ~10p off-peak
Import rate: ~24p/kWh off-peak (2am–5am); standard unit rate other times
Battery required: Yes (compatible battery)
Best for: Solar + battery households who want the best export earnings
Octopus Flux is the standout tariff for solar + battery households in 2026. The model is: charge your battery cheaply from the grid overnight (2am–5am at ~24p/kWh), top it up with solar during the day, then export to the grid during the 4pm–7pm peak window when the rate is ~30p. The battery acts as a trading vehicle, buying cheap and selling dear.
For this to work, your battery must be compatible with Octopus’s API. Supported batteries include GivEnergy, Growatt, Sigen, Powervault, and others. Octopus updates this list regularly.
3. Octopus Intelligent Flux
Export rate: Same as Flux (~30p peak)
Import rate: Same as Flux
Battery required: Yes (compatible battery with API integration)
Best for: Solar + battery households who want Flux returns without manual management
Intelligent Flux is the automated version of Flux. Instead of manually setting charge and discharge schedules, the Octopus system controls your battery automatically — it knows when grid electricity is cheap, when solar is generating, and when peak prices apply. It makes the charge/discharge decisions for you. If you are not interested in actively managing your battery, this is the version to choose.
4. Agile Octopus
Export rate: Agile Outgoing ~10–15p/kWh average (varies by half-hour)
Import rate: Changes every 30 minutes. Ranges from 2–5p/kWh at night or during windy periods, to 35p+ during peak demand. Occasionally goes negative (you are paid to use electricity).
Battery required: No, but battery amplifies the opportunity
Best for: Engaged households who actively shift usage to cheap periods
Agile is the most complex tariff but can deliver the lowest average import costs for flexible households. On windy or low-demand nights, prices frequently drop below 5p. If you have overnight loads (dishwasher, washing machine, EV charger), putting these on timers to run during the cheap window can cut those costs significantly. With a battery, you charge at 2–5p and use it during the expensive periods.
The downside: prices during peak periods (typically 4–7pm) can hit 30–45p. If you cannot shift consumption away from those peaks, Agile may cost you more than a standard tariff. It is a reward for flexibility, not a universal improvement.
5. Intelligent Octopus (EV Tariff)
Overnight charging rate: ~7–9p/kWh for the EV (smart-scheduled)
Best for: EV owners who want cheap overnight charging
Not a solar-specific tariff, but pairs well with solar. Intelligent Octopus works with compatible EV chargers to charge your car cheaply overnight. Combined with solar panels that reduce your daytime import, it covers both ends: solar reduces daytime import, Intelligent Octopus provides cheap overnight EV charging. See our EV charger installation page for compatible chargers.
6. Cosy Octopus (heat pump tariff)
Off-peak rate: ~14p/kWh in three time windows (morning, afternoon, late evening)
Peak rate: ~36p/kWh for the 4-7pm peak
Battery required: No, but pairs well
Best for: Heat pump (ASHP) owners, particularly with solar
Cosy Octopus is designed for heat pump heating. Three off-peak windows align with when your ASHP would naturally run hardest — morning warm-up, afternoon top-up, late evening pre-bed. If you have solar + ASHP + battery, Cosy lets the heat pump grab cheap grid power outside daylight, with solar covering most of the daytime demand. See our solar + heat pump guide for how to combine them.
Best Tariff by Setup — Quick Reference
| Your setup | Best tariff | Why |
|---|---|---|
| Solar only, no battery | Octopus Outgoing / SEG (best rate) | Maximise export rate per kWh — you can't shift export timing |
| Solar + battery | Octopus Flux or Intelligent Flux | Import/export arbitrage in the peak window |
| Solar + EV (no battery) | Intelligent Octopus Go | Smart EV charging at cheap rates + solar self-consumption |
| Solar + battery + EV | Intelligent Flux + IOG | Best of both — battery arbitrage and cheap EV charging |
| Battery only, no solar | Octopus Agile | Charge at 2-5p, discharge at 24-35p |
| Solar + heat pump | Cosy Octopus | Three off-peak windows match heat pump demand |
| No solar, no battery, flexible user | Octopus Agile | Reward for shifting consumption to cheap periods |
What You Need for Each Tariff
| Tariff | Smart Meter? | Compatible Battery? | Solar Required? |
|---|---|---|---|
| Standard SEG | Yes (SMETS2) | No | Yes |
| Octopus Flux | Yes (SMETS2) | Yes — API-compatible | Yes |
| Intelligent Flux | Yes (SMETS2) | Yes — API-compatible | Yes |
| Agile Octopus | Yes (SMETS2) | No (optional) | No |
| Intelligent Octopus | Yes (SMETS2) | No | No |
All smart tariffs require a second-generation smart meter (SMETS2). If you do not have one, your supplier installs it free of charge before switching you to a smart tariff.
Installing battery storage and want to qualify for Octopus Flux? We install compatible batteries across Milton Keynes and Buckinghamshire.
Battery Storage ServiceReal Numbers: Flux vs Standard SVT
Let us work through a realistic example for a 3-bed household with a 5kWp solar system and a 10kWh battery in Milton Keynes.
Assumptions:
- Annual generation: 4,500 kWh
- Self-consumption (before export): 2,500 kWh
- Annual export: 2,000 kWh
- Annual grid import: 1,500 kWh (after solar self-consumption)
- Battery allows 500 kWh to be exported specifically during the 4pm–7pm peak window
Standard SVT + basic SEG (10p export):
- Export income: 2,000 kWh × 10p = £200/yr
- Import cost: 1,500 kWh × 24.67p = £370/yr
- Net electricity cost: £170/yr
Octopus Flux:
- Peak export (500 kWh × 30p) = £150
- Standard export (1,500 kWh × 15p) = £225
- Total export income: £375/yr
- Off-peak import (1,000 kWh charged overnight at 24p): £240
- Standard import (500 kWh × standard rate): £123
- Net electricity cost: approximately –£12/yr (slightly in credit)
The difference: roughly £158–£200/yr better off on Flux for this household. Add the ability to charge the battery cheaply overnight and the benefit compounds further in winter when solar generation is low.
Real-world results vary. Some Flux households report £300–£500/yr gains over their previous tariff. The key driver is how much you can export during peak windows, which depends on battery size and usage patterns.
The Battery Requirement
The best solar tariffs (Flux, Intelligent Flux) require a compatible home battery. Not all batteries qualify. As of 2026, Octopus’s Flux-compatible battery list includes:
- Growatt (various models)
- SigenStor / SigenEnergy
- Powervault
- Huawei LUNA
- Fox ESS
- Others — check Octopus’s current compatibility list before purchasing
Tesla Powerwall does not participate in Octopus Flux. Instead, Tesla operates its own Virtual Power Plant (VPP) programme, which pays Powerwall owners for grid services. It is a different model with different economics.
See our battery storage page and our SigenEnergy page for details on compatible systems we install. For Tesla Powerwall, see our Tesla Powerwall page.
Octopus Flux rates, battery compatibility lists, and tariff availability change. Always check Octopus Energy’s current offer directly at octopus.energy before switching. The figures in this article were accurate at time of writing (May 2026) but may have changed.
Want to qualify for Octopus Flux?
We install Flux-compatible battery systems across Milton Keynes and Buckinghamshire. MCS & NAPIT certified. Fixed price. Free survey.
Battery Storage SigenStor (Flux compatible) AC Coupled RetrofitRelated guides
- Best SEG export tariff comparison
- SigenStor — Octopus Flux compatible out of the box
- Tesla Powerwall and the Tesla Virtual Power Plant
- All current solar & battery incentives
Frequently Asked Questions
For solar households with a compatible battery, Octopus Flux or Intelligent Flux is the best tariff in 2026. It pays around 30p/kWh during peak hours (4pm–7pm) and ~24p/kWh for overnight imports (2am–5am). For solar-only households without a battery, a standard SEG tariff at 12–15p/kWh export is the simplest option.
Yes. Octopus Flux requires a compatible home battery with API integration. Without a battery you cannot control when you export, so you cannot take advantage of the higher peak export rate. Compatible batteries include Growatt, SigenStor, Powervault, Huawei LUNA, and others. Tesla Powerwall has its own Virtual Power Plant programme rather than Flux.
Agile Octopus is a half-hourly pricing tariff. Import prices change every 30 minutes based on wholesale electricity prices — as low as 2–5p at night or during windy periods, and occasionally negative. During peak demand, prices can reach 35p+. Agile works well for flexible households who can shift consumption to cheap periods. It is not the simplest tariff and it rewards active management of your energy use.
A standard SEG tariff pays 10–15p/kWh flat. Octopus Flux pays ~30p/kWh during peak hours (4pm–7pm). A solar + battery household exporting strategically during peak windows could be £300–£500/yr better off than on a standard SEG. The actual gain depends on battery size, how much you can export during peak periods, and your overall consumption pattern.
Yes. All smart tariffs require a second-generation smart meter (SMETS2) that can report half-hourly consumption and export data. If you do not have one, your supplier installs it free of charge before moving you to a smart tariff. Smart meters are standard for all new solar installs and most households will have been offered one already.