UK Domestic Solar & Smart Export Calculator 2026

UK Solar Panel & Battery Storage Savings Calculator

Estimate your 25-year return on investment for home solar panels and battery storage. Tailored for UK roof orientations, standard variable import rates, and premium Smart Export Guarantee (SEG) tariffs.

0% UK VAT IncentiveSmart Export Income (SEG)Carbon Reduction Metrics

Property & Solar Array Parameters

UK Standard Benchmark

Annual Electricity Usage: 3,400 kWh / year(UK Avg ~3,400 kWh)

1,200 kWh (Flat / 1 Bed)3,400 kWh (3-Bed Semi)12,000 kWh (Heat Pump & EV)

Roof Pitch Orientation:

Solar Array Installed Size: 4 kWp(~10 Solar Panels)

2 kWp (~5 panels)4 kWp (~10 panels)12 kWp (~30 panels)

Pair with Home Battery Storage (e.g. 5.5kWh – 13.5kWh)?

Batteries boost solar self-consumption from 35% to 75% by storing daytime solar for evening peak use.

Grid Electricity Import Rate: 24.5p / kWh

SEG Export Guarantee Rate: 15p / kWh

Estimated Financial Returns

£841 / year

Combined bill reduction + Smart Export Guarantee (SEG) cash payout.

25-Year Cumulative ROI

£30,662

Assumes 3% annual grid inflation

Estimated Fitted Cost

~£8,800

0% UK VAT Applied

Estimated Payback

10.5 Years

Break-even timeline

Annual Generation

3,800 kWh

Solar power produced

Self-Consumed at Home: 2850 kWh (75%)Exported to Grid: 950 kWh

Environmental Impact: Offsets 0.79 tonnes CO2/yr (19.8 tonnes over 25 years).

Compare Tariffs with Best Export (SEG) Rates

Energy suppliers like Octopus (Outgoing Octopus 15p/kWh), E.ON Next (Next Export), and OVO offer premium export tariffs for home solar owners.

Complete UK Solar Guide 2026

How Much You Save Going Solar & How To Do It Step-by-Step

Everything you need to know about rooftop solar panel installation, 0% VAT rules, Smart Export Guarantee payouts, battery storage pairing, and break-even timelines.

How Much You Save

A standard 4 kWp rooftop solar array produces approx **3,800 kWh of clean electricity annually** in the UK, reducing annual grid import dependence by up to 75% when paired with a home battery.

**Direct Bill Reduction**: Saves **£850 to £1,200/year** on grid electricity.
**SEG Cash Income**: Earn **15p/kWh** on unused solar exported back to grid (~£150–£300/yr).
**0% UK VAT Incentive**: Government tax exemption saves **£1,000+ upfront**.
**Property Value Boost**: Upgrades home EPC score by 1–2 bands.

How To Do It (4-Step Process)

Transitioning to solar power in the UK is straightforward and usually completed in 1 to 2 days without major structural renovation:

Step A: Roof & Pitch CheckEnsure South, West, or East roof orientation with minimal tree/chimney shading.
Step B: Choose MCS Certified InstallerOnly MCS-certified installations qualify for 0% VAT and mandatory SEG export payouts.
Step C: DNO Grid Connection (G98/G99)Installer files G98 notification with your local DNO (UKPN, National Grid) for grid syncing.
Step D: Register for SEG Export TariffApply for Smart Export Guarantee with Octopus, E.ON Next, or OVO to receive quarterly payments.

What To Do / Next Steps

Maximal financial performance requires smart home energy management:

**Pair with Home Battery**: Adding a 5-10 kWh battery (e.g. Tesla Powerwall 3 or GivEnergy) stores daytime solar for evening use.
**Shift Heavy Loads**: Run washing machines, dishwashers, and EV chargers during 11:00–15:00 solar peak hours.
**Check Warranties**: Demand Tier-1 panels with 25-year linear power degradation warranties (≥ 85% yield after 25 years).