The H21 project has taken an exciting step forward in the last few weeks, as construction of the test sites at Buxton and Spadeadam got underway.
The H21 NIC project, when delivered in full, will have undertaken an experimental testing programme providing the necessary data to quantify comparative risk between a 100% hydrogen network and the existing natural gas network.
This information is requirexd for the UK to make a policy decision on decarbonisation of heat in the early 2020s, allowing for live trials to progress in 2020/2021 when combined with results of the BEIS Hy4Heat programme. This is examining hydrogen’s use ‘downstream of the meter’, in buildings and appliances.
Phase 1b involves controlled testing trials at the DNV-GL research centre at RAF Spadeadam in Cumbria. DNV-GL /NGN will conduct around 1,000 tests to look at various characteristics of how hydrogen behaves in comparison to our current fuel, natural gas.
The development of the Master Test Plan has defined a set of four experimental work packages, each with distinct build, experimental and analysis / reporting phases:
WBS1: Small Releases Defined as releases of hydrogen with leakage rates high enough to form a hazard but unlikely to break the surface in the case of buried releases.
WBS2: Large Releases Buried releases of hydrogen from larger hole sizes or higher pressure where the release is likely to find a direct route to the surface by crater, or fissure formation or through interference damage.
WBS3: Ignition Potential Idealised experiments to assess the likelihood of specific equipment providing an ignition source to hydrogen/air mixtures in differing equivalence ratios.
WBS4: Explosion Severity Specific to enclosures found on the network and other street furniture, these experiments are specified to provide information on the change in severity of explosion events in representative enclosures for hydrogen/air mixture of varying equivalence ratio.
As part of the trial programme NGN are building or revalidating the on-site test facilities at Spadeadam to undertake the above four packages.
One of the four test facilities to be constructed involves construction of a mini housing complex, set up so we can simulate as close as possible, albeit on a much smaller scale, how hydrogen behaves in a ‘real’ way in a ‘real’ environment which we can then compare against the results we already know for natural gas.
The construction contract for this segment of the works (WBS1) includes three two-storey houses with garage areas, gardens, cellar spaces, various types of internal walls and flooring, various cavity wall insulations. Essentially, this means any scenario which the teams have decided meets the needs of the master test plan is included within the design.
Secondly, an allotment of three sections where it is possible to change soil structures and surface finishes again allows us to meet the needs of the master test plan.
Thirdly, a 200m x 100mm steel ring main to feed the low-pressure PE outlets to all of the properties.
Next are Tarmac and paved ‘street’ surfaces, where all street furniture will be in place alongside utility manholes and ducts.
Lastly, we’re deploying an ex-NGN fleet Ford transit van to be rigged out with instrumentation to become the hydrogen metering vehicle.
We have some great progress to report after just four weeks on site.
Houses are fully internally carcassed like any other new build property. PIC
External and internal entry fittings installed as part of the build PIC An example of one of the floor types (block and beam), as other houses will have different structures.
We’ll continue to update with progress reports as the project continues.