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Manufactured in the UK
Cut Your Diesel Costs.
WattBox pairs solar and battery storage with your generator — so the diesel only runs when it has to. Keep your business running on a fraction of the fuel, fully independent of the grid.
- Complete energy independence from the grid
- Minimise generator running time and fuel spend
- Automatic generator backup when the battery runs low
- Use existing grid supply to get more power — no DNO upgrade required
Quarry in Wales
From running a diesel generator for 30 years to a 50kW solar system and 500kWh of batteries — reducing diesel costs and 100% off-grid in summer.
HOW IT WORKS
Solar and battery first. Generator only as backup.
WattBox sits between your solar array, battery and generator and manages them automatically. Energy always comes from the cheapest source first — sun, then stored power, then diesel only when there is no other option.
HOW IT WORKS
A day running on WattBox
Step 1
Solar powers your site by day
During daylight, solar panels supply your operation directly — running machinery, equipment and processes without a drop of diesel.
Step 2
Excess solar charges the battery
Any solar you are not using is stored in industrial batteries instead of being wasted, building a reserve for later.
Step 3
Battery runs your site into the night
When the sun drops, the battery takes over — powering your operation through the evening and overnight with stored solar energy.
Step 4
Generator auto-starts only when needed
If the battery runs low (typically in winter), the generator starts automatically, tops the battery up, then shuts off. No manual intervention, no power gaps.
Run your business on sunshine. Start the generator far less.
One box, hundreds of configurations
Every WattBox is custom-built to match your exact requirements.
Grid-tied or Off-grid
Compatible with any power source - stay connected or go fully independent
Single or Three Phase
Sized for homes, farms, or large commercial operations
32 kWh - 416 kWh storage
Modular battery banks that scale with your needs
10 kW - 350 kW solar
From small rooftop arrays to large ground-mounted systems
Works with existing solar
Already have panels? We integrate seamlessly with your system
Add backup generator
Optional generator integration for ultimate peace of mind
Common Questions
Straight answers about generators, fuel & going off-grid
Stop pouring money into the fuel tank.
Get your free off-grid plan in under 2 minutes. See exactly how much diesel WattBox would replace — no obligation, and if the numbers don't work, we'll tell you.
