How does a hydrogen boiler work?April 30, 2022
Unlike fuel cells, this type of system burns H2 in the same way conventional systems use natural gas.
A hydrogen boiler is just what you think it would be. It is a system that burns Hydrogen instead of using natural gas.
Appliances using hydrogen work quite similarly to the ones that are outfitted for use with natural gas.
Hydrogen boilers use combustion to burn the H2 gas, which produces hot flue gases which can be used for heating water. Once the water is hot, it can be stored to be used at a later time. Among the applications can be hot water that comes from a faucet or to warm up radiators throughout a home for home heating purposes, for instance.
Since H2 is thinner than natural gas, there are certain components that differ between the two systems. For instance, the burner and the flame detector are different between these two types of system. That said, they still essentially work the same way.
100 Percent hydrogen boilers have yet to become available as the energy technology is still in development.
Still, there are a few manufacturers that have created prototypes of the equipment, showing substantial progress in that direction.
The process these systems use is as follows:
- H2 from the main gas supply and oxygen from the ambient air enter the main unit. The gas inlet valves control how much gas can enter and, therefore, the size of the flame.
- The gases combine and are ignited in a catalytic burner. As H2 is more flammable than natural gas, the burners are specially designed to limit the flames if there is too much gas. As the flames are invisible, there is also a flame detection component required.
- Hot flue gases resulting from the combustion enter the heat exchanger. It is a series of pipes surrounded by cold water. As the heated gas moves through the pipes, it warms the water surrounding the pipes, supplying hot water taps or home heating systems.
- Byproducts – that is, water – exit the system through a condensate. The hydrogen and oxygen hot flue gases are also able to exit the system via a flue, without any NOx emissions from the H2 combustion.
From there, the hydrogen boiler continues drawing more H2 and oxygen to continue the process.
Currently, around 85% of homes are heated with natural gas and H2 technology is considered by experts to play a key role in the future of smart heating, because the main byproduct of burning hydrogen is just water. You may well know that by 2025 not far away, gas boilers will be banned from new homes in the United Kingdom and hydrogen is a fuel that’s supported by the government’s 10-point plan.
The big boiler manufacturers have promised that hydrogen-ready boilers and it is rumored that when they’re brought up to scale will cost no more than the existing natural gas boilers. On the supply side researchers are confident that they could easily pump hydrogen through the existing infrastructure.
People can expect once using hydrogen in your home to see that the flame is a slightly different color but otherwise the hydrogen cooks and heats exactly like natural gas. And that’s the main attraction for consumers. They are basically designed and engineered to be exactly the same as your natural gas boiler.
H2 Spotlight Question – What are the pros and cons of hydrogen energy? Discover the answers! Hydrogen energy comes with a lot of potential, but like everything else, it has its drawbacks too. Countries may be betting on a hydrogen economy to meet their climate change targets, but this doesn’t mean that there isn’t a downside worth considering. HFN can help you to learn both the strengths and weaknesses of this carbon emission-free fuel. You can also consider attending boiler training courses to learn more about boilers. For even more details, check out the information in the Learning Center and grab your copy of the free ebook. Don’t miss a single detail by signing up for the newsletter below.
This is a nice effort for net zero. Keep sharing best wishes.
Consultant hydrogen economy and sustainability
Hydrogen burners normally have higher NOx than a NG burner for the same burner design. Thus hydrogen burners nened to be designed to be low NOx and you mention a catalytic burner, which may be low NOx and invisible, but most hydrogen ready appliances have a NOx problem but no flame visibility problem as hydrogen diffusion flames are orange.
The UK Government BEIS hy4heat programme (2019 – 2022) has shown that viable visible low NOx hydrogen burners have been developed for gas cookers, gas fires and gas boilers. So there is no problem in decarbonising domestic heat using hydrogen, at a lower cost to the consumer than for heat pumps. The Government just needs to give the go ahead to repurpose the NG grid for hydrogen, the cost would be funded through the gas network payments in domestic gas bills, as is the current installation of yellow PE gas distribution pipes, which are also suitable for hydrogen,
Hydrogen will be the key fuel for Carbonless power and we have good technical solutions to the design of the system components. At present however it can only be used in domestic applications if every user in a district changes from gas to Hydrogen at the same time for the whole of each district.
This means complete replacement of the distribution pipework, monitoring and control installations and complete duplication, replacement and scrapping of the all the individual users old equipment in whole district wide changeovers. From past experience this type of project seldom works to time or cost. It is very doubtful if the public will accept the nuisance, interference of supply and costs of any such programmes and that they will be an easy target for political activists to try and kill.