Most people use a gas boiler to heat water in their homes. In fact, 23 million UK homes currently use gas boilers.

But there are several alternative water heating methods available. Some people can’t use gas because they are not on the grid, and so they often use oil or LPG (Liquid Petroleum Gas).

So what about more sustainable options?

Mains gas, while the most common way to heat water, is a fossil fuel that produces carbon dioxide. If you want to make your home more eco-friendly, it may be time to consider a sustainable hot water system.

Why change to an alternative water heating method?

If you currently have a gas boiler, here are a few potential reasons to change it for an alternative water heating method:

• Modern heating systems are very effective at heating water and there is a wide range of choices available for different budgets and home sizes.
• Gas central heating is expensive to install, requires annual maintenance and is not as efficient as many alternatives.
• There are more affordable alternatives available that can help you save money on heating your water and maintenance costs.

Perhaps the most important reason for many people to switch to an alternative method is that it can reduce their carbon footprint.

As part of the UK’s Net Zero target for 2050, gas boilers cannot be installed in new-build homes from 2025 onwards. So if you need a new boiler, it may be worth looking at an alternative.

While you can heat your home in a more sustainable way by using bioethanol fireplaces, you will have to resort to other options to heat water as bio fires are not meant to be used for heating of food or liquids.

Thankfully, there are several water heating options available. Here are seven of the best alternative water heating methods our experts would recommend if you’re looking for a more sustainable option.

1. Electric Water Heaters

Many households already use electric water heaters, and these can be a more sustainable option if you use electricity generated from green sources.

Electric combi boilers use electricity to warm the house and produce energy-efficient hot water. They make hardly any noise, are easy to use, and often come with features like touch screens and smart thermostats.

One of the benefits is that they heat up water for your shower faster. They are also small, making them a good option for smaller homes.

They tend to have lower installation costs because there is no need for new piping or ventilation systems when installing them, and they require less maintenance.

Also, the venting process with gas heaters means energy is lost, but this is not a problem with electric heaters.

However, they are typically more expensive to run than gas boilers, and they are not usually as effective at heating large homes.

2. Heat Pumps

Heat pumps are becoming increasingly popular in the UK, and it is likely that these will be the main heating option for new-build properties as the government attempts to hit its Net Zero targets.

In fact, the Government wants to install 600,000 of these each year by 2028.

You can choose from two main types of heat pumps:

• Ground source heat pumps
• Air source heat pumps

Both of these are sustainable options and are a good alternative to gas boilers, but they have some important differences.

Ground Source Heat Pumps

A ground source heat pump involves burying pipes in the ground in the property’s garden. These then extract heat from the ground and use the heat to heat hot water in the home.

Ground source pumps are a good option for very cold areas because soil temperature stays relatively constant throughout the year.

In a horizontal system, the pipes are installed up to two metres below ground, but vertical systems involve installing the pipes much deeper.

They are quite expensive to install, but running costs are low and not much maintenance is required. They are a more suitable option for properties with large gardens.

Air Source Heat Pumps

Air source heat pumps absorb heat from air instead of the ground. They can extract heat even when temperatures are very low.

They need to use electricity to extract the heat, but the heat output is greater than the input, making them an energy-efficient option.

They are suitable for homes with smaller gardens because they don’t require the amount of space as ground source heat pumps.

3. Hybrid Systems

Hybrid heating systems, also called dual fuel systems, combine two heating sources – typically an air source heat pump and a combustion furnace.

When using an air-source pump, if the temperature outside falls too low, it may not provide adequate heating. In this case, a hybrid system switches to the combustion furnace to top it up.

These are good low-carbon heating options because they have reduced carbon emissions compared to using a gas boiler on its own, and the running costs are lower. However, installation costs are high, and planning permission may be required.

4. Solar Water Heaters

Solar energy is one of the greenest options available and a good alternative to gas boilers for heating your water. It can be an excellent option if you want to reduce your carbon footprint.

Solar photovoltaic panels convert energy from the sun into electricity, so the electricity you generate is essentially free.

Solar panels also come with very low maintenance and low running costs, so once they are in position, there’s very little to do.

However, they have a few disadvantages. For a start, solar panels are expensive to install, which can be off-putting.

Solar panels are also affected by weather conditions, and they often need to be used in combination with a standard boiler to make the water hot enough, especially during cooler months.

5. Biomass Boilers

Biomass boilers are similar to conventional boilers, but instead of burning gas, they burn biomass – typically pellets made from wood waste.

Because they burn wood instead of fossil fuels, they are carbon neutral. They also provide a useful way to make use of waste wood and prevent it from going to landfill.

The pellets are also cheaper than fossil fuels and can often be sourced locally, making them a good option for off-grid properties.

Installation, however, can be expensive. The boilers also require a lot of space, so they may not be suitable for smaller properties. Maintenance is high in comparison to other options, and they can also be noisy, so they are not for everyone.

6. Micro-CHP Boilers

Source: viessmann.co.uk

Micro-CHP (Micro combined heat and power) systems are used to generate both electricity and heat using one energy source.

They are similar in size to gas boilers and are powered by either gas or liquefied petroleum gas (LPG).

While they rely on fossil fuels, they have a lower carbon footprint because when they burn gas, they provide both electricity and heat. However, they are more expensive to install than a gas boiler and they have similar maintenance costs.

7. Hydrogen Boilers

Hydrogen boilers are not an option just yet, but they have a lot of promise and could become a good water heating alternative.

One of the primary benefits of hydrogen boilers is that they will be able to use the current infrastructure, making them a more convenient option when it comes to switching from gas.

Many new boilers are hydrogen-ready, so they can be used to make the transition when hydrogen becomes a viable alternative.

However, hydrogen still presents many challenges regarding its feasibility. Producing hydrogen is not cheap, and hydrogen is also harder to store and transport than gas. At present, it is still a few years away from becoming a viable option.

Challenges of switching to a different water heating method

These are the main low-carbon heating options available for heating water in your home that are more sustainable than gas boilers. However, switching heating sources has several challenges:

• The cost of installation.
• The size of the new heating system and the amount of space you have.
• The need for planning permission with some of the heating options.
• The position of your home (e.g. when using solar panels).

These are all things to consider if you are thinking about switching from a standard gas boiler to a more sustainable alternative.

Government Incentives

As we’ve discussed, one of the largest barriers to switching to alternative water heating methods is the cost.

Fortunately, there are several government incentives that may help to reduce the costs and are well worth looking into.

• Boiler Upgrade Scheme (BUS) – This grant is available in England and Wales and runs until April 2028. It can be used to cover part of the cost of replacing your boiler with a biomass alternative or a heat pump.
• Home Upgrade Grant (HUG) – This is available in England for energy efficiency upgrades like heat pump installation.
• The Nest Scheme – This scheme is available in Wales to help low-income homeowners and tenants make energy efficiency improvements for their homes.
• Warmer Homes Scotland – This scheme provides interest-free loans or grants to make homes more energy efficient.
• Affordable Warmth Scheme – This scheme in Northern Ireland provides grants to make improvements to heating systems, insulation and more.

These incentives may or may not be an option for you, but they are worth looking at. Find more information on all of these government schemes.

Choose an alternative water heating method for your home

If you have a gas boiler and you’re considering switching to a more sustainable alternative, the above options should give you some ideas.

These energy-efficient hot water alternatives all have their pros and cons, and some are more expensive than others while some are more practical. Your choice will also depend on factors like the size of your property.

With gas boilers set to be phased out, now is a great time to choose an alternative water heating method. So start looking seriously at these heating alternatives and consider which is the right fit for your home.