Updated: Jun 2, 2021
With a diminishing supply of fossil fuels and growing concerns over greenhouse gasses, many industries are under pressure to find alternative energy sources. The UK government has pledged to reduce carbon emission, aiming for net-zero by 2050.
Central heating accounts for almost a third of UK greenhouse gas emissions; 8 out of 10 homes using traditional gas boilers. According to some experts, moving from natural gas to hydrogen boilers could be the answer.
What is a hydrogen boiler?
Put simply, a hydrogen boiler is one that runs on, you guessed it; hydrogen instead of natural gas. They are actually very similar to gas boilers and as such, only a few components e.g. flame detector and burner significantly differ. This is key as hydrogen boilers don't require any changes to the existing infrastructure.
Is hydrogen better?
Hydrogen boilers are more efficient and non-polluting. When it comes to emissions, only water is produced - not carbon like gas boilers. The amount of energy released from 2.8kg of natural gas can be achieved with just 1kg of hydrogen. As mentioned, moving from hydrogen to gas boilers would not require any changes to the gas network. This could see a seamless change for home owners, simply replacing the existing boiler with a new hydrogen model. Gas engineers would only require a small amount of additional training for the new fuel, much like those who currently deal with alternative fuels e.g. liquid petroleum gas (LPG).
Sounds great, what's the catch?
As witnessed in automotive and other industries; hydrogen is expensive to produce. The gas is not abundant on its own so has be produced. There are two main methods; Electrolysis, or Steam Methane Reforming (STR). Additionally, the lower density of hydrogen present challenges with storage and transport which aren't an issue with natural gas.
We also have to scrutinise the potential green credentials of hydrogen boilers beyond just the appliance itself. As is the case with many industries, whether it be electric cars or utilities, we have to consider carbon emissions of the final product as well as the impact from manufacturing and production process. Unless the energy from hydrogen production comes from sources such as wind or solar, it cannot be considered carbon neutral.
Is hydrogen the only answer?
No, but it is probably be the easiest and fastest method to reduce carbon emissions. Whilst technologies such as solar and heat pumps can be currently installed, there are a lot more barriers to entry. The former requires the up front cost of solar panels and even then not everyone's home is suitable. The latter works well in a purpose built home but most existing homes would need improved insulation as well new pipes installed which in a small property, can be challenging.
Can I install a Hydrogen boiler now?
Sort of. Whilst boilers that run on 100% hydrogen are not yet available, there are so called 'hydrogen ready' models available that can run a hybrid 20:80 mix of hydrogen and natural gas respectively. Switching to one of these models for your next boiler could be a smart move to future proof the heating system. In the meantime, manufacturers such as Veissmann, Worcester Bosch and Baxi have already reached final prototype stage so it is likely that these will be on sale in the next few years.
So, the silver bullet we need or just hype?
Time will tell but as we have seen with other industries, it may be a case of the right technology at the right time. As discussed, one of the biggest challenges with moving to a new energy source is the infrastructure. With such little change required, hydrogen boilers could potentially be rolled out at quite a pace. However, whilst it's easy to get excited by a single solution, we will probably see a range of alternative energy sources to tackle varying applications such as new builds, older homes and commercial properties.