Octopus Flux, Agile and Go: Which Smart Tariff Is Best for Solar and Battery Owners

Choosing the right Octopus Flux solar battery tariff or alternative smart rate can make a bigger difference to your annual savings than the brand of battery you install. With Octopus Energy offering several time-of-use tariffs designed specifically for homes with solar panels and battery storage, picking the wrong one could cost you hundreds of pounds a year in missed savings.

Octopus Flux vs Agile vs Go: Which Tariff Is Best for Solar and Battery?

For households with solar panels and a battery, Octopus Flux generally delivers the best overall returns because it offers premium export rates during afternoon peak hours when your battery can discharge to the grid. Agile suits households willing to shift usage around volatile half-hourly pricing, while Go is the simplest option for EV owners who mainly need cheap overnight charging.

This guide breaks down the three main Octopus smart tariffs for solar and battery owners, explains how each one works, and helps you decide which tariff matches your setup and lifestyle.

How Smart Tariffs Work With Solar and Battery Systems

Traditional electricity tariffs charge a flat rate per kilowatt hour regardless of when you use it. Smart tariffs vary the price throughout the day based on wholesale electricity costs and grid demand. For homes with solar panels and battery storage, this creates opportunities to:

• Charge your battery cheaply when electricity costs are lowest, typically overnight
• Use stored electricity during expensive peak hours instead of buying from the grid
• Export surplus solar at premium rates during peak demand windows
• Automate the process so your battery charges and discharges at the optimal times without manual intervention

The combination of solar generation, battery storage and a smart tariff can reduce annual electricity bills by 70 to 90% compared to a standard flat-rate tariff without solar. The tariff you choose determines how much of that saving you capture.

Octopus Flux: The Solar Battery Tariff Explained

Octopus Flux is specifically designed for homes with solar panels and battery storage. It divides the day into three price bands with different import and export rates.

The key advantage of Flux is the premium peak export rate. Between 4pm and 7pm, when grid demand is highest, Flux pays significantly more for your exported electricity than standard SEG rates. If your battery is charged with cheap overnight electricity and your solar panels are still generating in the late afternoon, you can export at 3 to 5 times the rate you paid to charge.

A typical day on Octopus Flux looks like this: your battery charges from the grid between 2am and 5am at the cheapest rate. During the day, your solar panels power your home and top up the battery. Between 4pm and 7pm, you export stored electricity at the peak rate while running your home from the grid or remaining battery charge.

Typical annual saving: homeowners with a 4 kWp solar system and 10+ kWh battery report savings of 800 to 1,400 pounds per year compared to a standard flat-rate tariff.

Intelligent Octopus Flux: Automated Optimisation

Intelligent Octopus Flux takes the standard Flux tariff and adds AI-driven automation. Instead of fixed charging windows, the system analyses weather forecasts, your historical consumption, wholesale prices and solar generation predictions to decide when to charge and discharge your battery.

The platform works with compatible batteries including Tesla Powerwall, GivEnergy and select others. Once connected, you set your preferences (such as maintaining a minimum charge level for backup) and the system handles everything else.

Benefits of Intelligent Octopus Flux include:

• Weather-aware charging: if tomorrow is forecast to be cloudy, the system charges more from the grid overnight to compensate for lower solar generation
• Price-responsive: on days when wholesale prices spike, the system maximises exports to capture higher rates
• Set and forget: no need to manually adjust charging schedules or monitor tariff rates
• Continuous improvement: the AI learns your household patterns and improves its optimisation over time

The main requirement is a compatible battery and inverter that can communicate with the Octopus Kraken platform. Check Octopus Energy’s website for the current list of supported devices.

Octopus Agile: Half-Hourly Wholesale Pricing

Octopus Agile is the most dynamic tariff available, with prices that change every 30 minutes based on wholesale electricity market rates. Prices are published at 4pm the day before, giving you 24 hours to plan your usage.

Agile rates can range from negative prices (you get paid to use electricity) during periods of high wind or solar generation, to over 100p per kWh during extreme peak demand events. The average rate across a year is typically competitive with standard tariffs, but the volatility creates significant opportunities for battery owners.

With a battery and smart controller, you can automatically charge during the cheapest half-hour slots and avoid or export during the most expensive ones. Some battery owners report buying electricity at 5 to 10p per kWh overnight and avoiding peak rates of 35 to 50p per kWh, creating savings of 3 to 5 pounds per day.

The risk with Agile is unpredictability. Prices can spike without warning during cold snaps or low wind periods, and if your battery is empty during a price spike, you pay the full premium rate. Agile rewards active management and suits homeowners who enjoy monitoring and optimising their energy usage.

Octopus Go: Simple Off-Peak for EV and Battery Owners

Octopus Go is the simplest smart tariff, offering a fixed cheap rate for a set number of overnight hours and a fixed daytime rate for everything else. It was originally designed for EV owners but works well for anyone with a battery.

The advantage of Go is simplicity. You know exactly what you will pay for overnight charging, and there are no half-hourly price fluctuations to worry about. The 5-hour overnight window is long enough to fully charge most home batteries from empty.

The disadvantage is that Go does not offer premium export rates. Your export payments will be at the standard SEG rate, which is significantly lower than the Flux peak export rate. This makes Go less suitable for homes with solar panels that generate significant surplus for export.

Best for: EV owners who also have a battery, homeowners who want predictable pricing, people who do not want to manage dynamic tariff complexity.

Octopus Flux vs Agile vs Go: Which Tariff Should You Choose?

Choose Octopus Flux if: you have solar panels and a battery, want premium export payments, and prefer predictable three-tier pricing. Flux is the best all-round tariff for most solar and battery homes.

Choose Octopus Agile if: you enjoy optimising energy usage, have a large battery (10+ kWh), and are comfortable with price volatility. Agile has the highest saving potential but requires more engagement and carries more risk.

Choose Octopus Go if: you primarily want cheap overnight charging for an EV and battery, do not generate much solar surplus for export, and value simplicity over maximum savings.

How to Switch to a Smart Tariff

Switching to any Octopus smart tariff requires a SMETS2 smart meter. If you do not have one, Octopus will install one for free. The process is straightforward:

• Ensure you have a working smart meter that communicates with your energy supplier
• Sign up with Octopus Energy or switch from your current supplier
• Select your preferred tariff through the Octopus app or website
• Configure your battery charging schedule to match the tariff windows
• For Intelligent Octopus Flux, connect your compatible battery through the integration setup

The switch typically takes 2-3 weeks if you are changing supplier, or can be instant if you are already an Octopus customer moving between tariffs.

If you do not yet have solar panels or a battery, get a free quote to find out how much a complete system would cost and what savings you could achieve on a smart tariff.

Frequently Asked Questions

Can I use Octopus Flux without a battery?

Technically yes, but the tariff is designed for battery owners. Without a battery, you cannot charge cheaply overnight or time your exports to the peak window. You would still benefit from premium export rates if your solar panels happen to be generating between 4pm and 7pm, but the savings are significantly reduced.

Do I need solar panels for Octopus Agile?

No. Agile works well with a standalone battery for tariff arbitrage, charging during cheap periods and discharging during expensive ones. However, adding solar panels increases your savings by reducing the amount of grid electricity you need to buy during the day.

Which Octopus tariff saves the most money?

Agile has the highest theoretical saving potential because of its extreme price variations, but it also carries the most risk. Flux is the safer choice with more predictable savings. For most solar and battery homes, Flux or Intelligent Octopus Flux delivers the best risk-adjusted return, with typical annual savings of 800 to 1,400 pounds.

Can I switch between Octopus tariffs easily?

Yes. Octopus allows existing customers to switch between tariffs without penalty. You can try Flux for a few months, switch to Agile to compare, and settle on whichever delivers better savings for your usage pattern. There are no exit fees or minimum contract lengths on most Octopus tariffs.

Are smart tariffs available from other suppliers?

Yes, though Octopus leads the market. E.ON Next offers the E.ON Next Drive tariff for EV owners, and several suppliers offer basic off-peak rates. However, Octopus Flux remains the only major tariff specifically designed for solar and battery homes with premium time-of-use export rates. British Gas, OVO and EDF also offer variable tariffs but with less integration for battery owners.