TÜV Rheinland has opened an H2 laboratory in Cologne to pave the way for the safe use of hydrogen in boilers, burners, and instantaneous water heaters: “We look at the efficiency of gas condensing boilers as well as the technical and structural requirements to make hydrogen safe to use,” Mario Reimbold explains. “Devices for operation with pure hydrogen are only just being developed,” says TÜV Rheinland’s business unit manager for heat generators. Because our laboratory also does product testing.
Because H2 has a lower calorific value volume than natural gas, the devices must allow for a higher gas flow. Only natural gas-certified boilers, burners, and instantaneous water heaters require an extra certificate.
“We assess the hydrogen compatibility of their gas condensing boilers on behalf of the manufacturers, and the German Technical and Scientific Association for Gas and Water (DVGW) issues the necessary certificate for an H2 admixture of up to 20%.” Mr. Reimbold explains, “We are now working on certification for functioning only with hydrogen.”
Last-mile dependability
The greatest focus is safety. This also applies to the “final mile” of the gas supply, which is the distance from the home connection to the burner for the building’s central supply or the apartment’s instantaneous water heater. Manufacturers and energy providers can also have fittings and valves examined at the TÜV Rheinland laboratory to verify that no hydrogen escapes.
A Vaillant prototype is the first gas condensing boiler on the laboratory test bench. “Right now, the first field testing for devices that run purely on hydrogen is taking place in the United Kingdom,” explains Lars Christiaans, head of Vaillant’s international licensing department. “We all establish the circumstances together – manufacturers, energy providers, and TÜV Rheinland as the testing service provider – to make climate-neutral hydrogen acceptable for heat generation in buildings,” says Lars Christiaans.
