H100 NIA: Domestic Metering Solution diagram
Project Name: Domestic Metering Solution
Project Lead: SGN
Partners: Kiwa Gastech Ltd
As a first-of-its-kind demonstration project, the H100 Fife green hydrogen gas network will potentially require the use of gas meters before dedicated hydrogen gas meters have been developed through the Hy4Heat programme. It is therefore important to understand what meters are currently available, and how supply of hydrogen will affect it.
Conventional diaphragm gas meters without smart metering functions or other sources of ignition should be suitable for hydrogen metering. Meter accuracy needs to be laboratory tested with hydrogen to prove or disprove functional performance.
Due to the volumetric calorific value of hydrogen being lower than that of natural gas, existing installed meters are unlikely to be large enough to meter the flows that will be seen in a hydrogen-heated property. Compact meters with sufficient hydrogen capacity for most domestic users are available from several suppliers, with dimensions that would allow their installation within conventional domestic gas meter boxes.
Larger domestic consumers would require meters with more capacity again, which would require installation of larger meter boxes. These are available as off the shelf items.
This project element delivered a batch of hydrogen gas meters, plus ancillary equipment, that will enable accurate hydrogen metering and effective customer interaction.
Key requirements
- We are specifying that the meter should contain additional safety devices to prevent accumulations of hydrogen gas in properties. After the meter, an Excess Flow Valve (EFV) will be installed to shut off the gas flow when there is a leak
- Meters will be located outside of the property to reduce likelihood of a ‘Gas in Building’ event