Savings calculatorWhat would solar save you?
Answer a few questions about your property. Results update as you go, and you can download them as a PDF quote or send them to us for a free survey.
1 · Property
2 · Location
3 · Monthly electricity
£75/ month
≈ 300 kWh / month · unit rate 25.0p/kWh
Electricity only, excluding the daily standing charge.
4 · Roof
Which way does the roof face?
Selected
South
Efficiency
100%
Compared with the best angle. Darker means more output.
Roof pitch
35°Usable roof area (if you know it)
5 · Solar panel
6 · System size
3.96kWpRecommended
7 · Battery storage
A battery stores daytime surplus for the evening, so you buy less from the grid.
Estimated payback
12.3years
Likely range 10.2 – 13.6 years
Net gain over 25 years
£7,170
- System size
- 3.96 kWp
- 9 × 440 W panels
- Area used
- ~23 m²
- Tiled
- Yearly generation
- 4,040 kWh
- 112% of your usage
- Orientation & pitch
- 100%
- South, 35°
- Solar used on site
- 36%
- used as it is generated
- Exported
- 2,570 kWh
- to the grid · ~£310 a year
- First-year savings
- £680
- lower bills + export payments
- Estimated cost
- £6,100–7,500
- installed · incl. 0% VAT
- Carbon saved
- 0.8 t
- CO₂ a year
Where does your solar go?
- Used directly
- 36%
- 1,470 kWh
- Exported to grid
- 64%
- 2,570 kWh
First-year value: direct use £367, battery £0, export £309.
Solar you use (directly or from the battery) saves the full unit rate. Exported solar earns the export rate under the Smart Export Guarantee.
A typical day
GenerationUsed directlyUsage
Monthly generation · Bristol
GenerationUsage
Cumulative savings over 25 years
Includes panel degradation (0.5% a year), yearly maintenance and an inverter replacement in year 12. Yearly price rise: 0%.
Suggested equipment
- SSolar panelsMono 440 W panel1762 × 1134 mm×9
- IInverterString inverter 3.6 kWG98 notification to the network operator×1
- MMonitoringApp-based generation monitoring×1
Estimates only (October 2026 prices). Your final quote follows a free survey of your property.
How accurate is the estimate?+
It is a sound first estimate, not a quote. Solar data comes from the European Commission's PVGIS database for your town (991–1,122 kWh per kWp a year across our area), adjusted for your roof's direction and pitch. Shading, the exact roof layout and your fuse board are checked at the free survey, and the final quote is fixed after that.
Which prices does it use?+
Typical October 2026 installed prices for our area, an electricity unit rate of 25.0p/kWh for homes and an export rate of 12.0p/kWh. You can change the unit rate, export rate and future price rises under "Advanced settings".
Is there VAT on solar panels?+
Solar panels and batteries installed on homes are currently zero-rated for VAT, so home prices shown include 0% VAT. Business prices are shown excluding VAT.
Do I need a battery?+
Not always. Without one, you typically use around a third to half of your solar directly and export the rest. A battery stores the daytime surplus for the evening, which raises your savings but also the upfront cost — the calculator shows both sides so you can compare.
Do I need permission?+
Most home installations are permitted development and need no planning application (listed buildings and some conservation areas are exceptions). Systems up to 3.68 kW per phase are simply notified to the network operator (G98); larger ones need approval first (G99), which we handle for you.
How do export payments work?+
Under the Smart Export Guarantee, your electricity supplier pays you for every unit you send to the grid. You need an MCS certificate, which we provide after installation.