Today, the amount of hydrogen (H2) admixed with natural gas in Germany’s grid is currently limited to ten percent. Several field trials in the past 12 months have demonstrated the safe application of higher admixtures, but with the project H2HoWi, North Rhine-Westphalia's grid operator Westnetz has gone a step further. Together with its partners E-ON and the H2 boiler maker Remeha it is testing the technical viability of using 100 percent H2 in the grid, piped directly into consumer boilers.
For the first pilot in October, a 500-metre-long section of the natural gas pipeline (part of the Westenergie AG Essen grid) was converted to pure H2 gas, supplied by a storage facility, and piped directly to three commercial customers for heating. According to Westnetz, the green hydrogen used for the pilot was 99.9 percent pure (quality level H2 3.0).
In the three connected commercial buildings, four H2-compatible boilers from Remeha then provided entirely CO2-neutral heat. Remeha’s 100 percent hydrogen boilers, which have been piloted in the UK, The Netherlands and France, have an output of 24 kW, with a 45 kW model to be launched shortly.
At the inauguration, North Rhine-Westphalia's Minister of Economics Mona Neubaur said that the project was doing "real pioneering work... Today we are walking 500 important metres towards climate neutrality," according to an article in .
Conventional gas condensing boilers cannot be operated on pure H2, so many heating companies are now making boilers that are H2-ready in anticipation of the share of H2 growing in the pipeline, as Germany is weaned off Russian gas.
According to a study commissioned by the heating industry, however, the market uptake of H2 boilers and the production trajectory for green hydrogen will be too slow to meet official climate targets. The next step for the manufacturer is to test the combination of H2 boilers and heat pumps, where the pump covers the base load and the boiler the peak load. For industrial customers, hybrid solutions may prove more workable.