◐ INDEPENDENT · UK · 2026

Will it pay back?
Show me the numbers.

Most home-energy sites are sales funnels in disguise. We're a calculator. Plug in your roof, your usage, your postcode — and see what solar, a heat pump, or a battery would actually save you. Honest maths, current grants, no nonsense.

Solar ROI calculator → Check my grants
◐ TOOLS

Ten calculators. Real maths.

SOLAR
Solar ROI calculator

Postcode-adjusted yield, SEG export earnings, battery uplift, 25-year payback.

10 inputs
BATTERIES
Battery payback

Solar self-consumption uplift + time-of-use arbitrage. The bit most quotes miss.

8 inputs
HEAT PUMPS
Heat pump & BUS grant

Net install cost after the £7,500 grant, running cost vs your boiler, payback.

7 inputs
EV
EV charging vs petrol

Home/public mix, EV-specific tariffs, honest petrol comparison.

7 inputs
EV
EV salary sacrifice

BIK tax, NI savings, net monthly cost vs private lease.

5 inputs
GRANTS
Grants eligibility

ECO4, Warm Homes, BUS, Nest, Home Energy Scotland — what you qualify for.

5 inputs
INSULATION
Insulation savings

Loft, cavity, solid wall, floor, draught-proofing — costs, savings, ECO4 eligibility.

6 inputs
TARIFFS
Octopus Go vs flat rate

Would a time-of-use tariff save you money? Models EV, battery and smart timer shifting.

6 inputs
COMBINED
Whole-home model

Solar + heat pump + battery + EV — combined install, savings and payback.

Interactive
EXPORT
SEG rates by supplier

Octopus 15p, E.On 16.5p, EDF, OVO and more. Updated monthly.

Apr 2026
◐ WHY THIS EXISTS

Most calculators flatter the numbers.

Solar quote sites tend to assume south-facing roofs, no shade, full self-consumption, and 15p export tariffs that almost no one gets. Heat pump comparison tools forget panel-radiator costs. Grant explainers don't say which schemes are closing this year.

We model the boring details — regional yield, panel degradation, battery time-shifting, grant overlaps — and we show our working. If solar isn't worth it for your roof, we'll say so.

◐ GUIDES

Read before you buy.

SOLAR · 8 MIN READ
Are solar panels worth it in 2026?

Current install costs, SEG income, when payback breaks even, and three roofs where it doesn't make sense.

UPDATED APR 2026
HEAT PUMPS · 7 MIN READ
The Boiler Upgrade Scheme, explained

£7,500 for ASHP, £2,500 for air-to-air (new), eligibility, MCS rules, and the application gotchas.

UPDATED APR 2026