How Much Could Your Garden Save You?
Pick a kit and tell us who's home in the daytime. You'll see the yearly saving, the total over 10 and 20 years, and the carbon you'd cut.
Checked 4 November 2026
How we calculate it
Saving = power made in a year × the share your home uses as it's made × your unit rate, rounded to the nearest £5.
- Power made. The Energy Saving Trust puts an 800W kit at about 700 kWh a year (south-facing, 30° tilt, unshaded, North West England). Smaller kits scale down. Bigger kits make extra in the mornings, evenings and on dull days but are held at 800W at midday, so we scale them up by panel power less a fifth of the extra: about 850 kWh for the Plus 1030W and 980 kWh for the Max 1260W.
- Used at home. Only power your home uses as it's made saves money. Busy family home (four of you, someone in all day, washing and dishwasher in daylight): 70%. Someone home most of the day: 58%. In and out: 49%. Out at school and work: 40%.
- 10 and 20 years. The yearly saving added up at today's unit rate, with the panels losing 0.5% of their output each year. If electricity prices go up, you'd save more.
- Carbon. About 0.131kg of CO₂e for every kWh you use from the panels instead of the grid (UK Government 2026 figure).
The Energy Saving Trust figure is for North West England. The West Midlands usually sees a little more sun over a year, so for a Birmingham garden it's on the careful side.
Every figure, and where it's from
| What | Figure we use | Source |
|---|---|---|
| Power made, 800W kit | About 700 kWh a year (south-facing, 30°, unshaded, North West England) | Energy Saving Trust: plug-in solar panels, updated 1 October 2026 |
| Kits over 800W of panels | Panel power × 875 kWh per kW, less a fifth of the extra above 800W | Our estimate, built on the Energy Saving Trust figure |
| Share used at home | 40% to 70% (70% = busy four-person home) | Based on Energy Saving Trust figures; 70% is our example for a busy family home |
| Unit rate | 26.32p per kWh, 1 October to 31 December 2026 (Direct Debit, GB average) | Ofgem price cap, announced 26 August 2026. The next cap is announced on 25 November 2026 |
| Power sent to the grid | Counted as zero | Self-installed plug-in kits don't generally qualify for export payments |
| Most a kit sends into your home | 799VA (3.5A), every kit | The maker's datasheets |
| Direction and shade | Not modelled | We don't have sourced figures for other directions or shade yet, so we don't guess them |
| 10 and 20-year totals | Today's unit rate, with panels losing 0.5% a year | Our assumption |
| Carbon saved | 0.131kg CO₂e per kWh used at home | UK Government GHG conversion factors 2026 |
An estimate, not a promise. Your result will depend on your garden, the weather and when you use electricity.
Five ways families use more of their own power
There's no battery with a plug-in kit, so the trick is using the power while the sun's out.
- 1Washer on in the daytimeSet the delay timer so it runs through the middle of the day.
- 2Dishwasher after breakfastRather than after tea. Same wash, sunnier timing.
- 3Charge the garden toolsMower, strimmer and e-bike batteries on a sunny afternoon.
- 4Slow cooker through the dayA low, steady draw that sunny panels can often cover.
- 5Watch the appThe microinverter's app shows what you're making, so you learn the sunny hours in your garden.
Seen your figure? Find the kit that fits your garden.