Hydrogen Boiler vs Heat Pump: Understanding Future Heating Scenarios

As the UK aims to achieve net zero emissions by 2050, one of the key challenges is how to decarbonise the heating sector. Two of the most discussed options are heat pumps and hydrogen boilers.

Both have pros and cons, and supporters and detractors. Heat pumps are being actively installed while hydrogen home heating is considered a viable alternative by many. We’ll peel back the layers on each to see what they offer in terms of energy efficiencies, cost savings, and green credentials. We’ll also consider the challenges of rolling out each technology and the current government position.

Hydrogen Boiler vs Heat Pump: Heating Systems of the Future

The UK Government has a definite stance on heat pumps. It sees the technology as crucial to help us move away from traditional boilers. Although there is plenty of discussion on hydrogen’s role in domestic heating, the government’s plans are less certain.

Let’s explore heat pumps and how hydrogen fits into the mix. Ultimately, a mix may be more likely rather than one or the other.

As Mike Foster, head of the Energy and Utilities Alliance, says about future energy: “We will need a wide range of technologies to achieve net zero – heat pumps, heat networks, and hydrogen boilers. That’s what current government policy states.”

Analysing heat pumps

Heat pumps use advanced, low-carbon technology that extracts and moves heat from one place to another, using a relatively small amount of electricity to do so. As a result, ground and air source pumps have emerged as a leading green solution for heating homes.

The UK Government views heat pumps powered by renewable electricity as a vital means to transition to greener energy to achieve the 2050 net-zero carbon targets.

The main types of heat pumps are:

• Air source heat pumps: This system draws thermal energy from the air, using a special refrigerant and compression to convert it into steam to heat your home.
• Ground source heat pumps: Ground source heat pumps extract heat from the ground through a network of pipes buried in the earth. The released heat is then circulated through your house.
• Water source heat pumps: These use the heat energy from nearby water sources to provide heating and hot water for your property.

Heat pump advantages

These systems provide low-carbon heating that potentially burns less fossil fuels and lowers your home’s carbon footprint.

When your pump uses renewable electricity from solar or wind power, it provides environmentally friendly heating that aligns with Net Zero. When it comes to heat pumps vs gas boilers, the prior are more sustainable and efficient than oil or gas, using electricity more efficiently than other heating systems – including those running on hydrogen.

Energy efficiency

Pumps are highly efficient when converting energy to heat. Compared to an electric boiler, a heat pump uses far less electricity to produce the same amount of heat.

Do heat pumps work in cold weather the same way a good gas boiler does? Opponents of heat pumps are quick to tell you that in really cold weather, heat pumps struggle to deliver the same warmth, especially in poorly insulated homes. They point to people keeping a backup heating system just in case their heat pump flops!

Costs

• Installation: Installing a heating pump is expensive. The average installation cost for air source pumps is £8,000 to £18,000, depending on the size, model, house size, and difficulty of installation.Ground source heat pump installation is even more expensive because the job involves more piping, U-loops, trenches, and labour. Cost estimates range from £20,000 to £30,000. If you need to dig a borehole, the pump can cost well over £40,000.Property owners in England and Wales can apply for £7,500 towards air or ground source heat pumps through the Boiler Upgrade Scheme(BUS).
• Running costs: Heat pump running costs depend on the pump design and how it is fueled and operated. Higher energy efficiency usually means lower utility bills, although savings also depend on the system you’re replacing.The Energy Savings Trust estimates that a semi-detached three-bedroom home upgrading from an old gas boiler to an air source heat pump saves £340 a year (based on January 2024 energy prices).

Analysing hydrogen boilers

A hydrogen boiler is similar to a gas boiler except for the fact that the unit is powered by hydrogen instead of natural gas.

Many existing boilers are hydrogen-compatible or mix-ready, meaning that they can take up to 20% hydrogen gas. Boilers that can take 100% hydrogen are not yet widely available.

Why use hydrogen instead of good old gas? When hydrogen burns, it emits hardly any carbon dioxide. It is the cleaner energy that the future demands. For Net Zero, the emphasis is on squeaky green hydrogen produced using renewable electricity.

Advantages of hydrogen boilers

Hydrogen can provide a high heat output and deliver the same levels of comprehensive heating as conventional boilers. This makes them great for homes in colder climates or properties with higher heating demands.

Converting to hydrogen boilers will be less disruptive to consumers than adopting heat pumps. For most homes, the project to switch gas boilers for hydrogen units will be easier than installing heat pumps.

Energy efficiency of hydrogen heating

Unlike heat pumps, which extract heat from the outside air or ground, hydrogen boilers can operate independently of external temperature conditions. This means they can consistently provide hot water and heating regardless of outdoor temperatures.

While a hydrogen boiler provides heating, it doesn’t produce it as efficiently as a heating pump. Hydrogen uses electrolysis to split water into oxygen and hydrogen. Wastage occurs at several stages in the process:

• The electrolysis process to produce the hydrogen is only about 75% efficient.
• Energy is used up in compressing and delivering the hydrogen to consumers.
• Energy is also lost in condensing boilers that burn the hydrogen to generate heat.

It’s estimated that pumps are 4-6 times more efficient than hydrogen boilers, meaning a pump delivers 4-6 times more heat into a building using the same amount of electricity.

Costs

• Installation: Leading boiler company Worcester Bosch says that hydrogen-ready boilers are not expected to be much more expensive than modern gas boilers. If this is the case, you could have a hydrogen boiler installed for under £5,000 – a cheaper prospect than a heat pump installation (though the £7,500 BUS subsidy narrows the gap).
• Running cost: Greenhydrogen can be produced from a range of clean energy sources. Ultimately, hydrogen could be more expensive than gas or it could be slightly cheaper depending on how it is produced and stored. Government incentives may also lower the cost.How does the cost of hydrogen heating compare to heat pumps? Due to their higher efficiency and lower energy consumption, heat pumps are the cheaper option.

Which is Greener – Hydrogen or Heat Pumps?

Green hydrogen boilers and heat pumps are both largely clean and efficient. While both appliances use renewable energy sources, the latter is generally greener.

This is because the overall process of generating and delivering electricity to power heat pumps creates fewer carbon emissions compared to hydrogen production, transportation, and combustion.

As electricity generation increasingly comes from green sources, directing this toward heat pumps is an excellent way to decarbonise our homes.

To understand hydrogen’s eco credentials, know that there are four types of hydrogen:

• Black/brown hydrogen – produced from coal.
• Grey hydrogen – produced from natural gas.
• Blue hydrogen – produced from gas with carbon capture built in.
• Green hydrogen – which uses electricity from renewable sources like solar, hydra, and wind, and uses electrolysis to split water into oxygen and hydrogen.

Green hydrogen is the only eco-friendly option here – black and grey are clearly dirty. Powering boilers with blue hydrogen is cheaper but emissions are unacceptably high and it’s not an environmental win.

Challenges of Adoption

There are pretty sizable challenges to rolling out heat pumps and hydrogen systems successfully.

Heat pumps

• It’s estimated that an additional 100,000 heating engineers will have to be trained to handle installation and servicing.
• Realistically, the cost of pumps needs to come down. Not many households have a spare £40,000 lying around to spend on a new pump. Prices should drop as technology advances and demand increases.
• The national electricity grid will need to be increased to handle over 20 million new heat pumps.

Hydrogen boilers

• The gas network of thousands of miles of pipes will require a substantial upgrade. In particular, older steel pipes will have to be replaced because they are less compatible with hydrogen than plastic polyethylene piping. Another hefty price tag!
• Engineers who work on gas boilers will have to be trained to work with hydrogen setups.
• Like natural gas, hydrogen gas poses a safety risk. All safety concerns about hydrogen will have to be addressed.

Looking Ahead

Future of heat pumps

The government is pushing ahead with its heating pump plans. In late 2023, the Boiler Upgrade Scheme increased the grant for pumps by 50% to £7,500.

With costs hopefully falling and electricity becoming greener, heat pumps remain viable. However, given performance issues and cost, don’t expect heat pumps to dominate the heating market as natural gas boilers did.

Future of hydrogen

The outlook for hydrogen is less clear. This is why hydrogen-ready gas boilers aren’t in mass production.

The National Infrastructure Commission (NIC), the UK’s infrastructure watchdog, is firmly opposed to this heating option. In 2023, following an extensive investigation, the NIC concluded that hydrogen is not suitable for heating homes. In December 2023, the UK Government supported plans to ban hydrogen-ready boilers from new-build homes in England from 2025.

The government has said it still sees the gas network as a crucial part of the country’s energy system, so it will continue working with the heating industry to explore hydrogen’s role. Additionally, conventional gas boilers will still be with us for a couple of years – even decades. In September 2023, the government announced they were slowing down the phasing out of gas boilers.

FAQs

Does the Boiler Upgrade Scheme offer funding for a hybrid heat pump system?

A hybrid heat pump system does not qualify for a grant under the BUS. Some homes use a hybrid heat pump system – such as a combined gas boiler and air source heat pump – for their domestic heating.

Is hydrogen more dangerous than natural gas?

Hydrogen is considered more dangerous than natural gas. It is more prone to leaking, ignites at a lower energy, and is potentially more explosive forming a bigger blast.

How do heat pumps and hydrogen boilers benefit from renewable energy?

Both heat pumps and hydrogen boilers can play a significant role in integrating renewable energy sources into the heating sector, contributing to a more sustainable and low-carbon energy future.

How much money is available in BUS?

As of February 2024, the Boiler Upgrade Scheme has been funded by £1.5 billion.

Conclusion

Home heating in the UK will look different in 2050, but it’s hard to predict exactly how heat pumps and hydrogen boilers will feature in the new regulations. It’s best to keep up to date with the latest developments, including following the latest news from Eco Happy.

If you need guidance about heating pumps, are concerned about a hydrogen future or need advice on any other heating matters, please contact us at Eco Happy to assist.