Poujoulat chimney ranges already compatible with hydrogen

As France and Europe move away from fossil fuels, the potential of hydrogen as an energy carrier is attracting a great deal of interest. While its use is currently limited mainly to industrial applications, in the not-too-distant future it could be extended to other sectors, including energy for buildings. In this respect, hydrogen is already the subject of a great deal of research and experimentation.

Having said that, the question then arises of compatibility with heating equipment, and more specifically with flues: are our chimney flues suitable for hydrogen? Is there any impact on the flue? Here are some of the answers.

What you need to know about hydrogen

Hydrogen is not an energy source in its own right, like wind or biomass, because it has to be produced by a chemical reaction, such as electrolysis: the water molecule H2O is split into hydrogen (H2) and oxygen (O). Hydrogen is rarely found in its natural state (at the bottom of the ocean, underground).

Hydrogen holds great promise...

- Hydrogen has great energy potential,

- It is non-toxic,

- It does not pollute, since its combustion generates only water and no greenhouse gases,

- It is safe, as it diffuses faster than natural gas.

... But there are still a number of technical challenges to be resolved before hydrogen can be produced and used on a large scale:

Its production is only worthwhile if the means of production is carbon-free,

- Transporting and storing hydrogen remains complex,

- It is difficult to detect because it is an odourless, colourless gas and its flame is invisible.

Hydrogen in buildings

Numerous research projects have already been launched in the Netherlands, the UK and France to demonstrate the use of hydrogen in buildings. There are two main types of project:

- Those based on injecting 20% hydrogen into the gas network,

- And those based on 100% hydrogen use.

The conclusions of the various studies show that hydrogen combustion has the following impacts:

- The quantity of condensate is reduced,

- Hydrogen combustion uses less combustion air,

- And the volume of combustion products is reduced.

What impact will this have on the flues used to evacuate combustion products?

- Up to 20% hydrogen injection:

Studies show that there is no impact on existing systems (for type B or C appliances), sensitive boiler components or flues.

- With 100% hydrogen:

Boilers running on 100% hydrogen are already available on the market, but are currently only used in pilot projects. These 100% hydrogen installations require a specific study to design the flue.

Which Cheminées Poujoulat ranges are compatible with hydrogen?

For hydrogen combustion projects of up to 20%, our following flue ranges are suitable and this type of use is covered by our guarantee:

- DUALIS CONDENSATION, the flue for condensing boilers

- FLEXCONDENS, the single-wall flexible flue pipe for condensing boilers

- CONDENSOR, the connecting flue and casing for multi-fuel boilers

- THERMINOX, the double-wall insulated flue pipe for multi-fuel use

- THERM+ CHP, the double-wall insulated flue for mini-cogeneration

For projects using more than 20% hydrogen, a specific dimensioning and feasibility study must be carried out by our Cheminées Poujoulat Customer Design Office.