Net zero is impossible without batteries
To reach net zero, we need clean electricity even when the wind drops and the sun sets. Batteries store surplus wind and solar power for later, helping us use more renewables and burn less fossil fuel.
Wind & sun vary
Clean power depends
on the weather
Store the surplus
A battery keeps it
for later
Less fossil fuel
Stored power fills
the gaps
In the International Energy Agency’s net-zero scenario, global electricity storage grows sixfold from 2023 to 2030, with batteries providing 90% of the increase. Read the IEA report.
A smart battery saves you £700 per year
Kilowatt Club offers:
- £1,000 towards a battery and installation: £3,700 → £2,700
- The Brain controls the battery, making it save around £700 a year
Charge cheap, power the peak
A real day on the club’s test battery
Monday 7 September 2026 · FoxESS EP12 · UK time (BST)
The Pi planned to charge from 13:00–16:00 and export from 18:00–20:30. The charts pair the real tariffs and saved plan with the grid readings we recorded.
Loading the recorded day…
Import
What electricity cost to buy
Export
What electricity earned from the export tariff
Shading shows the saved plan, not proof of delivery. Bars are averages of available five-minute grid readings; hatching means no readings. Recording ended at 20:06 and missed much of the export event. The 19:00–20:00 Axle event is marked separately; its reward is not included in the export tariff.
The Pi’s saved plan for this day
Last plan update: 20:00 BST. Self-use lets the inverter manage the battery for the home; hold keeps its charge. Power is the planned battery power, not measured grid power.
| Time (BST) | Plan | Battery power | Import (p/kWh) | Export (p/kWh) |
|---|
Download this day’s data · Recorded example, not a live feed.
Mission first
Our goal is to get a battery in every home. While we think our grant makes Kilowatt Club the most competitive way to do this, if you don’t want to join the club, please get a battery anyway. Some great options:
- Octopus Energy
- Tesla Powerwall
- Predbat — an open-source controller for third-party batteries, similar to The Brain
£15/month
Cancel any time and the Brain reverts to a timer, still covering a lot of the savings.
Join our waitlist and you could have a battery in a month
Join