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Energy Saving Calculator

Enter your home details and we'll show you exactly which improvements will save you the most on energy bills - ranked by payback period, with costs, savings, and CO2 estimates.

Prioritised savings plan10-year projectionCO2 reduction estimateNo email wall
Modern central heating radiator in a well-insulated UK living room

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How this calculator works

Our energy saving calculator analyses your home and identifies which improvements would save you the most on energy bills. You tell us your property type, age, size, current heating system, insulation levels, and window type. The tool then generates a personalised list of upgrades ranked by payback period, showing the installation cost, annual savings, and CO2 reduction for each one.

The 10-year projection accounts for energy price inflation (assumed at 4% per year based on recent trends) and shows the cumulative savings over time. This helps you see how quickly each improvement pays for itself and how much you would save in total. Where applicable, the tool also notes available grants and schemes that could reduce your upfront costs.

Savings estimates are based on data from the Energy Saving Trust and Ofgem, adjusted for your property details. Every home is different, so actual savings will depend on how you use your heating, the quality of installation, and your specific energy tariff. These figures are a useful guide for prioritising improvements, but a professional home energy assessment will give you the most accurate picture.

Frequently asked questions

What is the cheapest way to reduce energy bills in the UK?
Loft insulation and draught-proofing offer the fastest payback. Topping up loft insulation to 270mm costs £300–£600 and can save £150–£250 per year. Draught-proofing doors and windows costs £100–£300 and typically pays for itself within two years.
How much can I save by insulating my home?
A typical 3-bed semi-detached house with poor insulation could save £400–£700 per year by adding loft insulation, cavity wall insulation, and draught-proofing. The exact saving depends on your property type, age, and current heating system.
Is it worth getting solar panels in the UK?
For most homeowners, yes. A typical 4kW solar panel system costs £5,000–£8,000 and saves £300–£700 per year, giving a payback period of roughly 8–15 years. You also benefit from the Smart Export Guarantee, which pays you for electricity you export back to the grid.
Should I replace my boiler or get a heat pump?
If your boiler is old and inefficient, a new condensing boiler (£2,000–£3,500) offers a quicker payback. A heat pump costs more upfront but gives greater long-term savings and qualifies for the £7,500 BUS grant. Heat pumps work best in well-insulated homes.
What home improvements give the best return on energy savings?
In order of typical payback: loft insulation (1–3 years), draught-proofing (1–3 years), smart thermostat (2–3 years), cavity wall insulation (3–5 years), new boiler (7–10 years), solar panels (8–15 years), and heat pump (8–15 years after BUS grant).

How we calculate these estimates

Our savings estimates are based on typical costs and energy reductions published by the Energy Saving Trust, Ofgem, and the UK Government's Energy Performance Certificate database. We adjust for your property type, size, age, region, and current heating system. Actual savings depend on your specific property, usage patterns, and the quality of installation work. We assume 4% annual energy price inflation for the 10-year projection. Always get at least three quotes from qualified professionals before going ahead.

Our methodology|Last updated: April 2026

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