Top 7 eco alternatives to gas boilers for a greener future

A huge 80% of British households are warmed by gas central heating systems. And almost a quarter of the UK’s total carbon emissions come from our homes².

So, considering the current climate crisis, and the recent report from the  Intergovernmental Panel on Climate Change (IPCC) which states that the climate crisis has undoubtedly been caused by humans - it’s up to all of us to rise to the challenge of cutting down our carbon emissions.

We need to do as much as we can, as quickly as possible, to slow down the rising temperatures that are causing climate change. 

Why look at alternatives to gas boilers?

Gas boilers and gas central heating systems are damaging to the environment, because of their high carbon emissions. So it's time to decarbonise heat and find greener alternatives, for the health of our planet. 

When will gas boilers be phased out?

The recent Heating and Building Strategy³ stated that the government aims to begin phasing out the installation of new natural gas boilers from 2035. But no specific, legally binding regulatory decision has been made.

What will replace gas boilers in the UK?

With gas boilers potentially on the way out, we have to act quickly to fill the enormous gap left by gas central heating. Read on to find out about the alternatives that are being suggested as possible low-carbon solutions. 

What are the benefits of these eco-friendly alternatives?

In order to reach that all-important 2050 net zero target, the Energy Saving Trust says we need to cut our heating emissions by 95%. The only way to do this is by replacing our heating systems, with greener alternatives. 

And if saving our planet isn’t motivation enough, you could also save energy and money. Read on to find out your options for a greener future. 

Top 7 green alternatives to gas boilers to heat your home the eco way

1. Heat Pumps

Air source heat pumps (ASHPs)

What is it? 

ASHPs work in the same way as a fridge, but in reverse – they take the energy from the air outside (even when it’s cold), and convert it into heat for your home. 

Pros: 

• Potentially lower fuel bills, depending on your current system
• Fewer carbon emissions 
• Very energy-efficient 
• Safer than gas
• Low maintenance 
• Some models can cool your home as well as heat it
• Long lifespan – about 20 years
• Getting an ASHP installed outside frees up space inside

Cons:

• You may need to upgrade radiators in your home as some heat pumps get get water less hot than a boiler
• High upfront cost to install
• Only homes with outside space can get one
• Some (usually older) models can have rather noisy outdoor fans
• Low efficiency if outside temperature is below zero
• The home must be well-insulated

Costs: Between £8,000 to £12,000

Interested? You could be eligible for the government’s Renewable Heat Incentive (RHI). This scheme offers quarterly cash payments over 7 years for those who install low-carbon heating systems.

This incentive will be replaced in April 2022 by the Boiler Upgrade Scheme. The new scheme will offer £5000 up front, to help with the cost of installing an air source heat pump. 

If you're interested in being a heat pump pioneer, share your contact details via this link, and we'll make sure you’re the first to know about OVO’s green tech offers and trials. 

For more information about ASHPs, read our complete guide to air source heat pumps

Ground source heat pumps (GSHPs)

What is it?

A GSHP absorbs heat from the ground, using pipes that are buried outside in your garden – and transports this heat into your home.

Pros:

• Potentially lower fuel bills, depending on your current system
• Fewer carbon emissions
• Some models of GSHP can cool your home too
• Safer than gas
• Low maintenance
• Long lifespan

Cons:

• High upfront cost to install
• Most effective if you have underfloor or air heating systems
•  Disruption to your garden during installation
• Only possible if you have a garden

Costs: Between £10,000 and £18,000

Find out if you’re eligible for the government’s Renewable Heat Incentive (RHI) which offers quarterly cash payments over 7 years. This incentive will be replaced in April 2022 by the Boiler Upgrade Scheme. The new scheme will offer £6000 up front, to help with the cost of installing a ground source heat pump.

Find out how you could use a GSHP as your gas boiler alternative with our guide to ground source heat pumps

2. Heat Batteries

What is it?

Smart electric boilers that charge up using cheap, off-peak renewable energy, and deliver heat to your home when needed. They look and work just like a boiler, but are powered by green electricity.

Pros:

• Fewer carbon emissions
• Very efficient
• Cheaper than a heat pump - starting at around £5,000⁸
• Easy to install : most can fit where your boiler is, or in a space the size of a washing machine
• Long lifespan: some models are expected to last more than 20 years⁹
• Work with existing radiators and pipework
• No need for outside space
• Work with Solar PV and other renewables & electric batteries

Cons:

• Weight: even the smaller units weigh more than100kg. Which means they must be installed on a solid floor and will need some lifting equipment to move into place (provided by the installer).

• Rely on off-peak electricity such as Economy 7 or other off-peak tariffs to be cheap to run.

• Expensive if charged up during peak times or without a time-of-use tariff.

• Not yet widely available. But several companies will be offering heat batteries from 2022.

  Costs: between £3,000 - £12,000

  The cost depends a lot on the size of your home. A typical 3-bedroom semi-detached house would be around £5,000.

  The Heating and Building Strategy¹⁰ stated that the government will look at ways to rebalance energy levies away from electricity to gas over the next decade. This would mean systems using electricity could become cheaper to run.

3. Hybrid heating systems

What is it?

A hybrid heating system is a similar idea to a hybrid car. It combines a heat pump with a gas boiler and alternates between the 2, depending on which is most efficient at the time.  

Pros:

• Fewer carbon emissions
• Very efficient
• Some models can cool your home as well as heat it
• Longer life-span than just a boiler, as the boiler is only used part-time
• Balances eco-friendliness of heat pump with reliability of a boiler

Cons:

• High upfront cost
• Not as eco-friendly as other low-carbon solutions
• Need some outdoor space

Costs: between £5000 and £10,000

Find out if you’re eligible for the government’s Renewable Heat Incentive (RHI) which offers quarterly cash payments over 7 years. This incentive will be replaced in April 2022 by the Boiler Upgrade Scheme.So you may well be eligible for some money up front towards one of these systems. 

4. Infrared heating panels 

What is it?

These panels look a little like normal radiators, but are run on electricity and emit infrared energy as heat. 

Pros:

• Fewer carbon emissions
• Low maintenance
• Completely silent
• Safer than gas
• Take up little space and are portable

Cons:

• Don’t heat the air, so the room feels immediately colder when switched off
• The panels have a short range of up to 3 metres
• You won’t feel warm if an object is between you and the heater
• Infrared energy travels through glass, so they mustn’t be placed opposite a window

Costs: between £150 to £500 per panel

Find out if you’re eligible for the government’s renewable heat incentive (RHI) which offers quarterly cash payments over 7 years. 

The Heating and Building Strategy said that the government will look at ways to rebalance energy levies away from electricity to gas over the next decade. This would mean systems using electricity could become cheaper to run.

5. Solar thermal panels

What is it?

These panels work together with a main heating system. They capture the sun’s energy in a special fluid  and use it to heat the water in your home. 

Pros:

• Lower fuel bills
• Fewer home carbon emissions
• Low maintenance
• Low running costs

Cons:

• Weather dependent
• Can’t be used as sole source of energy
• Not compatible with all heating systems
• High upfront cost

Costs: between £5000 to £7000 depending on the type of home

Find out if you’re eligible for the government’s renewable heat incentive (RHI) which offers quarterly cash payments over 7 years. 

6. Biomass boilers and stoves

What is it?

Biomass boilers work in a similar way to gas boilers. Instead of gas, they burn sustainably sourced material such as wood and plant-based materials.

Pros:

• Cheap fuel
• Fewer home carbon emissions
• Efficient way to use up waste wood and plants
• Practical for remote locations

Cons:

• These boilers can be 4 times as big as gas boilers
• High upfront cost
• High maintenance (due to ash and soot) 
• You’ll need space to store the fuel

Costs: between £5,000 and £13,000 depending on the size and type of home, and the type of boiler used. 

Find out if you’re eligible for the government’s renewable heat incentive (RHI) which offers quarterly cash payments over 7 years. 

7. Solar-powered electric heating

What is it?

Solar panels are groups of photovoltaic (PV) cells that turn sunlight into electricity. 

Pros:

• Lower fuel bills for space heating and hot water
• Fewer home carbon emissions 
• Safer than gas
• Totally silent
• Easy to install
• Costs of installation is dropping all the time
• Low maintenance costs
• You can earn money by selling electricity back to the grid with the Smart Export Guarantee (SEG)

Cons:

• Not all homes are suitable
• Relatively low efficiency levels
• Cost of installation is high, but dropping
• Solar power is reliant on the sun, so you may want to consider battery storage too 

Costs: between £2,500 and £8,000, depending on how many solar panels you need and the size of the home

Traditional alternatives to gas boilers

Modern low-carbon alternatives aren’t the only options available. Other ways of heating homes have been around for decades. So which boilers are eco-friendly, and which aren’t? 

Electric boilers

Although your gas boiler has some electrical components, an all-electric boiler uses only electricity to run. This means if you’re with a green energy supplier like OVO, they can run on 100% renewable electricity⁵. So they definitely tick the eco-friendly box. 

Plus, they’re much safer and less high maintenance than gas or oil boilers. The downside is they can’t pump out as much energy as their gas equivalents, meaning only small homes can benefit from using them. 

Traditional oil or LPG boilers (not eco-friendly)

Although not sustainable or eco-friendly, for those living off-grid, using oil or liquid petroleum gas (LPG) has been a reliable solution for many years. 

They’re a relatively inexpensive alternative (although more expensive than gas) but it does mean you’re keeping high volumes of highly flammable liquid on your property.

Also, the Heating and Building Strategy of October 2021 stated that installation of new oil and LPG boilers will be banned in homes as of 2026. 

How much are the eco-friendly options?

All the eco-friendly alternatives to a gas boiler come at varying costs. Take a look at the following table to see how much you can expect to pay for each option. 

What is the eco mode on a boiler?

Putting your boiler in eco mode simply means your pre-heating function will be switched off. In normal or comfort mode, the pre-heating function gives you instant hot water. In eco mode, you have to run the water for around 10 to 12 seconds. It uses less energy, so it’s slightly cheaper. 

What about hydrogen boilers?

You may have heard the buzz about hydrogen boilers. Read all about them in our guide to hydrogen boilers, and find out if they really can be the solution to net zero home heating. 

So, what is the best alternative to gas central heating for me?

What gas boiler alternative you should choose depends on what kind of home you live in. For example, if you have outside space, you could look at installing a heat pump.  Or, if you have a slanted south-facing  roof, you might want to go with solar. 

It also depends on where you live, the size of your home, and how well-insulated your home is. And of course, cost is a big factor in any purchase. 

But, because of the government’s RHI scheme, - and it's successor, the Boiler Upgrade Scheme - now is a great time to replace your nasty carbon-creating gas boiler if you can. 

What are the challenges when making the switch from gas boilers?

Us Brits love our gas boilers, and it’s not going to be an easy task to wrest them out of the nation’s homes. 

As with any new technology, there are always early adopters and those who drag their heels. When it comes to low-carbon heating systems, many critics are concerned about the costs. But, as the market grows, prices will drop. And there’s the government’s RHI and SEG schemes, which sweeten the deal a little. 

Although green tech can be expensive to install, running costs are much lower, and it will likely last up to twice as long. In the case of heat pumps, they can generate 3 or 4 units of heat for every unit of electricity⁶, making them far more energy-efficient. So to really understand the benefits of low-carbon heating, we need to look at the long-term, not just the short-term. 

But, there is another challenge. Not all “green boiler” solutions are possible in every home. If you don’t have a garden, for example, you can’t get a ground source heat pump. And if you have a flat roof, then solar panels aren’t going to work for you. But, with the number of low-carbon options available, it’s likely you’ll be able to find at least  one that’s suitable for your home. 

Finally, a much broader issue is the overall infrastructure. For everyone to use electrical heating systems, we’ll need a heck of a lot of electricity. And for the electrical systems to be green, they need to be powered by a heck of a lot of green energy. This is something the UK is working hard on. Our main source of renewable energy is wind energy. We already generate enough of it to supply 11 million homes⁷, and the 10 point green plan unveiled by the government last year promised huge investment in this area.

We’re also working hard on new tech such as vehicle-to-grid charging and demand side response, which support the UK’s transition to a zero carbon energy system. Keep your eye on Planet OVO (our content hub), and we’ll make sure we keep you updated with all the new innovations coming from within OVO and worldwide. 

Sources and references:

^{1. https://www.bbc.co.uk/news/science-environment-58130705}

^{2. https://es.catapult.org.uk/brochures/decarbonisation-heat/}

^{3. https://www.gov.uk/government/publications/heat-and-buildings-strategy}

^{4. https://www.thermalearth.co.uk/blog/gas-boilers-banned-new-homes-2025}

^{5. 100% of the renewable electricity we sell is backed by renewable certificates (Renewable Energy Guarantee of Origin certificates (REGOs)). See here for details on Renewable Energy Guarantee of Origin certificates and how these work. A proportion of the electricity we sell is also purchased directly from renewable generators in the UK.}

^{6. https://cat.org.uk/info-resources/free-information-service/energy/heat-pumps/}

^{7. www.renewableuk.com}

^{8. https://tepeo.com/}

^{9. https://www.caldera.co.uk/warmstone-tm-fa}

^{10.  https://www.gov.uk/government/publications/heat-and-buildings-strategy}