Independent UK home energy calculators
We don’t capture your details, route you to installers, or earn commission on the result. Just transparent calculations using authoritative public data, with every assumption shown and every source dated.
Heat pump savings
Compare a heat pump's annual cost against your current gas, oil, or LPG heating - including the £7,500 BUS grant and your local price cap rates.
Solar + battery payback
Calculate solar panel returns with optional battery storage, including comparison across all current SEG export tariffs.
Grant eligibility
Which UK grants you can actually get, across all four nations - Boiler Upgrade Scheme, ECO4, and the Scottish, Welsh and Northern Irish schemes. No details captured.
Battery-only ROI
Does a battery charged on cheap overnight electricity pay for itself? Models the whole tariff switch, including the day-rate penalty most calculators ignore.
Is my energy use normal?
Your annual electricity against three million UK household profiles, by property type, heat pump and EV - plus what each month should cost, and why Ofgem's typical figure is lower than the real average.
Open data
UK domestic electricity consumption, by household type
The aggregates behind these calculators, published in full: 150 cohorts covering property type, EPC band, month, heat pump and EV ownership, each with a mean daily total and an hourly load shape. Free to use commercially, CSV and JSON, no registration.
Take the dataWhy another calculator hub?
Most existing tools are built by installers, manufacturers, or energy suppliers. They’re free because they capture your details for sales follow-up. The numbers they produce often nudge toward a particular outcome.
We aim to be different: independent, evidence-based, and fully transparent about every assumption and data source. Each tool shows when its underlying data was last verified.
Energycosting is independent and currently free to use. We’re focused on getting the calculations right and the dataset trustworthy before anything else. If you find the tool useful, the best thing you can do is share it with someone who’d benefit.
Guides
Plain-English explainers on the decisions behind the numbers - every figure sourced and dated.
How much electricity does a heat pump actually use?
Not modelled from SCOP - measured across 45,602 UK heat pump households. Why the headline figure is nearly three times too high, and what the honest number is.
Heat pump vs gas: the honest UK numbers
Does a heat pump actually cost less to run than a gas boiler? The real arithmetic, the SCOP that decides it, and the cases where gas still wins.
Why home batteries mostly don’t pay for themselves
The tariff switch nobody models, the losses nobody counts, and the capacity ceiling that makes a bigger battery earn nothing.