Could a heat pump, solar or a battery cut your bills?

This is a rough guide to help you decide what to look into, not a quote and not financial advice. Your home and installer will make the real difference. Nothing you enter here is sent to us or stored anywhere: it all stays on your device.

Your prices

We use the Ofgem price cap for 1 October to 31 December 2026, as on our energy prices guide. If your tariff is different, change these and everything updates.

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Your home

• We estimate floor area from the number of bedrooms, and heat use from the type of home and its EPC rating. We matched these to how much gas real homes in the South East used in 2023, from the government's National Energy Efficiency Data-Framework. Tested against it, our estimate sits within the middle half of real homes for every type and size of home, and is typically within 4 percent of the median.
• Real homes rated E, F or G use only a little more gas per square metre than homes rated D, because people in colder homes often heat less. We use that real pattern for bills, but the EPC rating still sets the size of heat pump a home needs.
• If you choose your bills, we work backwards from them instead, taking off standing charges. Bills are the better guide, because they reflect how you actually live.
• Boiler efficiency: gas 87%, gas warm air 78%, oil 85%, LPG 86%. Oil has about 10.35 kWh per litre and LPG about 7.08 kWh per litre.

Costs

• Air source heat pumps: the median cost for each size under the Boiler Upgrade Scheme in 2025/26, from about £11,500 for a small unit to £15,500 for a large one. Our range uses the spread of real installs in April to June 2026, when the median was £12,908 and the middle half cost £11,128 to £15,627 (DESNZ, Boiler Upgrade Scheme statistics, August 2026). Size comes from your home's floor area and rating.
• Ground source heat pumps: £18,000 to £42,000, the middle half of installs in April to June 2026 (median £27,232).
• Warm air homes: we add £4,000 to £7,000 for radiators and pipework. This is our rough allowance, not official data.
• Solar panels: £1,546 to £2,150 per kW, from the median and average costs of home installations in April 2025 to March 2026 (DESNZ, Solar PV cost data, May 2026).
• Batteries: about £3,000 to £4,500 for 5 kWh, and £4,500 to £7,500 for 10 kWh. There are no official figures for batteries, so these come from 2026 market prices. Treat them as the least certain.
• Grants: £7,500 towards a heat pump, or £9,000 for oil and LPG homes until 31 March 2027 (gov.uk).
• Loans: up to £20,000 for an air source heat pump, £35,000 for ground source, £15,000 for solar and £15,000 for a battery. Repayments are worked out like a normal fixed-rate loan, with no fees (gov.uk).

Savings

• Heat pumps make about 3 units of heat for each unit of electricity (we use 2.6 to 3.4 for air source and 3.2 to 4.0 for ground source). For gas homes, we include closing your gas account unless you tick that you would keep a gas hob.
• Solar in Sussex makes about 950 kWh per kW a year on a south-facing roof and 800 on an east or west one. You use some of it yourself, which saves the full electricity price, and are paid for the rest.
• Batteries save by storing spare solar power and cheap overnight electricity. We assume about 300 charges a year, and compare a 5 kWh and a 10 kWh battery to show whichever pays back sooner for your home.
• Your bills after the plan never go below your electricity standing charge, which you still pay however much you save.
• Carbon uses the UK Government's 2026 conversion factors: gas 0.182, heating oil 0.247, LPG 0.215 and grid electricity 0.144 kg of carbon dioxide equivalent per kWh. The car comparison uses 0.267 kg per mile for an average car. A battery saves money but little carbon, so we do not count any.
• If Forest Row did this together multiplies your results by 289 homes: one in ten of the roughly 2,890 homes in the area that includes Forest Row (Valuation Office Agency, March 2026). Every home is different, so treat it as an illustration.
• All savings use today's prices. Prices will change, and VAT on electricity is due to return on 1 July 2027.