All the alternatives to gas boilers, explained

All the alternatives to gas boilers, explained

Finding alternatives to gas boilers and switching to electric heating systems, powered by renewable electricity, is one of the most urgent changes we need to make in the UK to reduce our carbon emissions. 

Globally, heat accounts for nearly half of all energy consumption and 40% of energy-related carbon dioxide emissions. It is estimated that 19% of the UK’s greenhouse gas emissions come from warming up the places we live and work

Heating UK homes accounts for around 14% of our carbon emissions so, switching the 87% of UK households (22 million homes) to alternatives to gas boilers would make a massive dent in UK emissions.

The government has announced that by 2025, all new homes will be banned from installing gas and oil boilers but, if you’re living in a home which is currently heated by gas what are the best alternatives to gas boilers? And which option is most cost effective?

In this in-depth post we examine the available alternatives to gas boilers.

Alternatives to gas boilers

There are seven main alternatives to gas boilers to provide central heating and hot water, each of which we explain in detail on the following pages:

However, solar thermal and infrared heating panels will require an additional heat source to provide heat and hot water all year round.

We’ve summarised the alternatives to gas boilers, their installation costs and running costs in the table below. Keep in mind that every property is different and these are only estimations. Costs for specific properties can vary considerably depending on size, location, how well insulated the property is and what sort of heating system is being replaced, size of radiators, and a range of other factors.

Heating typeGas boilerAir Source Heat PumpGround Source Heat PumpInfrared Heating PanelsSolar thermal heatingBiomass boilerElectric Combi BoilerDry Core Storage boiler
Can heat the whole house?YesYesYesYes NoYesYesYes
Additional heating required?NoNoNoYes for hot waterYesNoNoNo
Installed cost for 3 bed home£3,800 to £4,500£7,000 to £13,000£14,000 to £19,000£2,800£3,000 to £5,000£14,000 – £20,000£1,500 to £4,500£4,500 to £6,500
Boiler Upgrade grant£0£5,000£6,000£0£0£5,000£0£0
Typical annual running cost £1,307£1,127£845£250£75£1,800£2,500£1,700 
ProsMost homes already have oneCan be efficient with CoP of 3+,
Low or zero carbon, Combines well with solar PV,
Grants available to reduce installation costs
Can be efficient with CoP of 4+,
Low or zero carbon, Combines well with solar PV,
Grants available to reduce installation costs
Minimal installation costs, Operates silently,
Takes up little space,
East to maintain, Highly efficient
Zero carbon, Little maintenance required, Minimal running costs
Carbon neutral, Escape the energy grid and suppliersLow install costs,
Well suited to smaller homes,
Virtually silent,
Works well with solar,
No risks of CO, Easy to maintain, Zero carbon 
Virtually silent,
Works well with solar,
No risks of carbon monoxide, easy to maintain, Zero carbon
ConsNot efficient, high carbon emissionsHigh upfront cost,
Higher electricity bills,
Beware of badly designed or installed systems which deliver a lower CoP
Very high upfront cost, Requires ground space + hot water tank,
Higher electricity bills,
Beware of badly designed or installed systems which deliver a lower CoP, Significant installation works
Doesn’t warm the air, so rooms feel colder immediately when switched off,
Short range of up to 3 metres,
Not effective if objects are placed between the panels and people,
Cannot heat water
Can’t meet 100% of hot water or heating, Requires a secondary heating system,
Installation costs
Very high upfront costs,
Pellet boilers can be noisy, Must maintain, Pellet boilers require electricity, Availability and price of fuel,
Fuel requires space,
Flue requires space & must meet regulations
Higher running costs than gas,
Won’t work during a power cut,
Not suited to larger homes
Higher running costs than gas

Assumptions:

  • 3 bed house, previously using 12,000 kWh of gas a year, (2.5% for cooking) paying 10.3p/kWh + 28p/day for gas, with an 85% efficient gas boiler plus 3,000kWh of electricity at 34p/kWh
  • ASHP with a CoP of 3.0, GSHP with a CoP of 4.0
  • 8 x 500W Infrared panels at £350/panel but only 1 switched on for 8 hours/day each between Oct 1 – March 31
  • Biomass boiler using 3 tonnes of pellets/year at £600/tonne
  • Electric combi boiler 11kWh, sufficient to power 8 radiators
  • Dry core storage boiler with storage running on Economy 7 / night tariff of 17p/kWh

The UK Boiler Upgrade Scheme – grants for installing low carbon heating

The UK government was running the Domestic Renewable Heat Incentive (RHI) to incentivise low carbon heating. In April 2022 the RHI was replaced by the Boiler Upgrade Scheme, which provides grants to cover part of the cost of replacing fossil fuel heating systems with a heat pump or biomass boiler. This scheme is open to people in England and Wales. If you live in Scotland, you might be able to get an interest-free loan or a grant to make your home more energy efficient. If you live in Northern Ireland, you might be able to get a grant to replace your boiler.

The boiler Upgrade Scheme provides grants of:

  • £5,000 towards an air source heat pump
  • £6,000 towards a ground source heat pump
  • £5,000 towards a biomass boiler

Check if you’re eligible for the UK Boiler Upgrade Scheme, and find out how to apply for the grant.

Choosing the best alternatives to gas boilers

Selecting the best alternative to a gas boiler is no easy task and will depend on the type and size of your home. But don’t even consider any of the alternatives to gas boilers until you have insulated every single aspect of your home.

Don’t even consider any alternatives to gas boilers until you have super-insulated your home.

There is one action you must take before any other to reduce emissions and improve the efficiency of your home and that is: INSULATE. Don’t assume your home is well insulated, or that you have done all that can be done. In reality, there is always more you can do to insulate, reduce your bills and improve the thermal efficiency of your home.

There are so many ways to improve thermal efficiency that this point can never be made enough. Heat escapes from walls, floors, roofs, ceilings, windows and fireplaces – anywhere there is an air gap is costing you money and none of the alternatives to gas boilers will be worth your while if your house is letting hot air leak out. Also, consider installing smart radiator valves to shut off the heating in unoccupied rooms.

Alternatives to gas boilers for flats and smaller homes

We’ve produced the following decision making trees to try and help you through the maze of alternatives to gas boilers. They are only guides and your final choices may vary depending on your home, but hopefully they provide a useful guide for the order in which to consider the options.

Alternatives to gas boilers for flats and smaller homes

Alternatives to gas boilers for larger homes

Alternatives to gas boilers for larger homes

Conclusion

There is no one-size-fits-all answer which provides a comprehensive alternative to a gas boiler. Much as we would all like to go zero carbon the reality is that, with the price of electricity being three times the price of gas, electric boilers unfortunately cost more to run than gas boilers. This may well change, and if you have the roof space to generate even some hot water or electricity from solar these are probably the first technologies you should consider installing, once you have insulated your home as much as possible, whatever type of house you have.

Solar thermal and solar photovoltaics capture a completely free source of energy so have no, or very very low running costs – making your home lower carbon and smarter too. Solar thermal can often cover all of a home’s hot water requirements for around 9 months of the year reducing hot water heating bills dramatically. Solar PV systems, of a sufficient size, can provide all of the electricity to power a home and work very well in conjunction with air or ground source heat pumps to reduce the costs of electricity for heating. When combined with batteries, solar PV opens up the possibility to trade energy, providing additional income to subsidize the cost of heating your home.

Air source and ground source heat pump systems are fairly expensive to install and need to be well specified to match your home’s heating system in order to work efficiently. But, when switching from gas to a heat pump which consumes electricity that costs three times more it can take a very long time to see a return on your investment.

Infrared heating panels came out very well in our assessment of alternatives to gas boilers because they are very efficient but they may not be for everyone, or suited to every situation. Since they heat objects and people directly via radiant heat, as opposed to the convective heat from traditional radiators, they are not terribly effective at heating an entire house at once but, since we rarely need an entire house to be warm at the same time – and they work well when combined with occupancy sensors to deliver heat instantly when and where it’s needed – they do offer an effective alternative to gas boilers, for space heating.

Electric combi boilers are a good alternative to gas boilers for flats and small homes. They’re relatively cheap to install and very efficient but, with the price of electricity being three times more than gas, as a direct replacement for a gas boiler an electric combi boiler is highly likely to increase your energy bills.

For larger homes an electric dry core storage boiler offers a viable alternative to gas boilers, with lower running costs than a combi boiler because they can take advantage of smart tariffs which offer lower electricity prices at night, and via Economy 7. But a dry core storage boiler costs more to install than an electric combi boiler and requires more space too, because it needs a heat store.

Biomass boilers are another option for larger homes and provide a good, low carbon alternative to a gas if you have a source of biomass to burn. But if you need to rely on fuel to be delivered, biomass will rarely be a truly zero carbon option, and leaves you susceptible to fluctuations in the price and availability of biomass fuel.

Whichever way you choose to go, remember: insulating your home as much as possible gives the fastest payback of any alternatives to gas boilers.  

If you decide to stick with a gas boiler check out Heatable who offer fixed price quotes and next day installation anywhere in the UK.

We hope the information here helps you make an informed decision and to reduce your bills and carbon footprint.