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Can you use Axle with a Feed-in Tariff? Yes, here's how
If you're on an old FIT, you've probably been told your battery can't earn from exporting. For everyday export that's often true. But grid events are a different thing, and they can work alongside your FIT.
The FIT problem
Older Feed-in Tariffs pay you for every unit your panels generate, and usually pay a "deemed" export rate on top, assuming half of it goes back to the grid whether it does or not. Those payments are often good, which is why most people keep them.
The catch is that many suppliers won't put you on a separate export tariff, such as the Smart Export Guarantee or Agile Outgoing, while you're still on FIT. So you can't sell your everyday surplus at a market rate, and a battery mostly ends up soaking up your own solar.
Why grid events are different
Grid events aren't an export tariff. When the electricity network is short of power, a company like Axle asks batteries to send power back for a short time, and pays for every unit exported during that window. It sits on top of whatever tariff you already have.
Axle says on its own site that it works with any energy supplier, tariff, or FIT arrangement, and you keep your existing tariff. At the time of writing it pays £1 per kWh exported during an event, with events typically happening a few times a month.
I run a home near Wrexham on an old FIT with a Fox ESS battery and Predbat Cloud. We kept the FIT because it pays well. Day to day the battery doesn't export: it charges from solar and from cheap overnight slots, and powers the house. The only time it sends power back is during Axle events, and those pay.
What you need
- A supported battery. Axle lists brands including GivEnergy, Fox ESS, SolaX, Solis, SolarEdge, AlphaESS and Sigenergy. It checks your system when you sign up.
- A working smart meter. Axle pays from your meter readings, so it needs to read your export.
- Your FIT left exactly as it is. You don't need to switch supplier or give anything up.
Getting set up
- Check your system qualifies on Axle's sign-up page.
- Sign up and connect your inverter. Axle then controls the battery during events only.
- If you use Predbat, connect Axle there too, so your battery plan leaves room for events instead of fighting them.
- Leave some charge in the battery during the evening, when events are most likely, so there's something to export.
FIT schemes vary, and the rules on adding a battery to a FIT system have changed over the years. If you're unsure what your agreement allows, ask your FIT provider before you change anything. Axle's terms and payments can change too, so check their current offer.
Is it worth it?
For a FIT household with a battery, it's money you otherwise couldn't earn at all, and it doesn't touch your FIT payments. Earnings depend on how many events there are, how big your battery is, and how much you're allowed to export, so treat any figure as a guide, not a promise.
The Axle button is my referral link. If you sign up through it I may get a reward, and it doesn't change what you're paid. Last updated 17 October 2026. This is my experience, not financial advice.