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Home Grants & Energy2 min check

Energy Bill Savings Calculator

Estimate annual savings from upgrading your home's energy efficiency, based on EST and Ofgem benchmarks.

Short answer

The biggest annual savings on a typical UK 3-bed semi: solar PV (£900–£1,100), cavity wall insulation (£285), loft insulation to 270mm (£250), smart thermostat (£75). Total potential: ~£1,700/year — though most homes won't capture all four. Payback ranges from 2 years (loft top-up) to 8–10 years (solar).
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Your home

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How it works

The calculator uses Energy Saving Trust 2024 benchmarks for a typical gas-heated 3-bed semi at the current Ofgem price cap. It sums the per-measure savings you select, then shows the percentage reduction against your stated bill. Higher bills generally mean larger absolute savings.

Worked example

£2,400 annual bill, no insulation, no solar → adding loft + cavity + smart controls saves ~£610/year (25% off) for a payback under 4 years. Add solar and battery and you double that.

Who should use this

  • Homeowners planning a phased retrofit
  • Renters checking which low-cost measures are landlord-approved
  • Anyone shocked by their last winter bill

Common mistakes

  • ×Installing solar before insulating — wastes generation
  • ×Overspending on a smart thermostat without a wet heating system
  • ×Cavity wall insulation in unsuitable exposed homes (causes damp)
  • ×Believing 100% savings claims from cold-callers

Frequently asked questions

Should I insulate or get solar first?

Insulate first. Reducing demand makes any later renewable system cheaper and smaller.

Is a battery worth it?

Increasingly yes — pairing a 5kWh battery with solar typically adds £200–£400/year by exporting at peak times and using cheap overnight Octopus tariffs.

Will savings keep up with prices?

If energy prices rise, your savings rise too — that's the hidden upside of efficiency.

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