Calculators in development
We are building these in 2026, in priority order:
- Heat pump payback calculator — air-source vs. ground-source, with your annual gas usage, electricity tariff, BUS grant eligibility, and retrofit costs.
- Solar + battery storage ROI — based on your roof, postcode irradiance, current tariff, export rate, and battery cycling assumptions.
- Insulation breakeven — cavity, loft, internal/external wall — by EPC band, fuel type, and grant eligibility.
- Smart heating savings — realistic, not the manufacturer claim. Different patterns for working households, retired households, families with young children.
- Whole-home retrofit budget — sequencing the works in the right order to avoid expensive rework.
How we model
Our calculators are deliberately conservative. We use:
- Median real-world performance figures, not best-case.
- Current Ofgem cap and exposure to typical tariff variation, not unrealistic switching scenarios.
- Full installation cost ranges (low / mid / high) so you can stress-test against quotes.
- Grant rates that are confirmed at time of publication, with explicit dates so you know if the model is current.
- Sensitivity analysis — what happens if electricity tariffs change, if the home performs better or worse than spec, if the grant scheme rules tighten.
While the calculators are being built
If you have a specific decision you're trying to model — heat pump quote, solar proposal, insulation contractor — and you'd like an independent second opinion before signing, get in touch. We'll model it for you, free, in exchange for letting us anonymise the inputs into the calculator development.