Hydrogen offers a pathway to the decarbonisation of heat, but it needs political will. A report by NGN on hydrogen conversion in the North seeks to aid the debate.

The biggest barrier to a hydrogen gas grid will be a lack of political will. The decarbonisation of the power sector has gone largely unnoticed by customers and there has been little impact on their everyday lives because the costs have been largely been hidden from view.

That was the message from Malcolm Keay, senior research fellow at the Oxford Institute for Energy Studies, who said the same will not be true for the decarbonisation of heat.

Speaking at the Low Carbon Networks and Innovation conference in October, Keay warned that hydrogen conversion would be too expensive and too disruptive to escape customers’ attention.

He said ministers will therefore be reluctant to bear the associated political costs. Unless the industry takes the lead, hydrogen networks will be doomed to remain a pipe dream.

Hydrogen in the North

As if answering that clarion call, last week saw the publication of the H21 North of England report, which represents the latest attempt by gas networks to present ministers with a clear policy choice.

Report author Northern Gas Networks had already laid out plans to convert the gas network in Leeds to run on hydrogen in its H21 Leeds City Gate report published in 2016.

In partnership with Cadent and Equinor, the company has now extended the blueprint to cover the whole of the North of England, including another nine major cities: Bradford, Wakefield, York, Huddersfield, Hull, Liverpool, Manchester, Teesside and Newcastle.

The conversion, which would cost £22.7 billion, would encompass more than 3.7 million households and 40,000 businesses.

The report includes proposals to extend the scheme to another 12 million homes in the UK by 2050 through a six-stage rollout. It could eventually provide 70 per cent of all domestic, industrial and commercial heating in the country.

Utility Week spoke to Dan Sadler and ­Henrik Solgaard Andersen, the respective H21 programme directors for Northern Gas Networks and Equinor, to find out more.

Given the rationale to deliver a “deep decarbonisation” of heating, one of the most important questions is how the hydrogen would be sourced. Sadler says that over the long run the fuel could ultimately be produced by passing surplus renewable electricity through water – a process known as electrolysis.

But renewables will need to become much cheaper and far more plentiful for this to be viable. In the meantime, hydrogen could be extracted from natural gas using another technique called auto thermal reforming.

Ninety-four per cent of the carbon dioxide released as a by-product of the process would – according to the report – be captured and stored in saline aquifers under the North Sea. The hydrogen produced would have a carbon footprint of 13.1gCO2/KWh and would itself be stored in salt caverns to help meet winter peaks in demand.

The production would most likely take place at a 12GW “megaplant” by the Easington gas terminal near Hull.

“It’s close to where we have a gas supply from Norway,” Andersen explains. “It’s very close to potential inter-season storage in the Albrough area, where you already have natural gas storage in salt caverns.

“And it’s also close to where we expect to store CO2 in the southern North Sea in the area called the Bunter Closure, which is 100km to 150km out from the coast of Easington.”

He says the facility would be capable of delivering up to 110TWh of heat a year, which is more than enough to meet the 85TWh of annual demand from the first phase of the project covering the North of England.

Sadler says the system has been designed to deliver the same level of security of supply as the current gas grid, which was “validated” by the Beast from the East earlier this year. “The Beast from the East was only one day,” adds Andersen. “Our system is designed to deliver that for 30 consecutive days”.

To minimise costs, the H21 programme would reuse the low-pressure gas pipes owned by distribution networks.

But, comparing the gas system to a chocolate fountain, Sadler says the project would also require the creation of parallel transmission infrastructure to allow small sections to be gradually switched over one by one: “If you fill the top one with chocolate, effectively you fill all of them up with chocolate straight away.”

The new hydrogen transmission system would be routed past all the existing or historic power station sites.

Sadler says this would create the opportunity for hydrogen to be “diverted” to combined-cycle gas turbines to provide backup generation for intermittent renewables – particularly during the summer when there is surplus hydrogen production and wind output is low. “It’s a totally complementary system,” he says.

To speed up progress and limit disruption, the work would be undertaken by three teams working in parallel – one for Yorkshire, beginning in Leeds; one for the North West, beginning in Manchester; and one for the North East, beginning in Teesside. The conversion would take place over a period of seven years, beginning in 2028 and finishing in 2034.

“What you’re doing is geographically splitting your workforce, so you can achieve the outputs quicker,” says Sadler.

He says individual customers would have their gas supply disconnected for a maximum of five days: “But actually for the most vulnerable customers it would be less than one day because you would target them first.”

The conversion would also be carried out during the summer “when gas demand is at its absolute lowest, so disruption is at an absolute minimum”.

None of the options for decarbonising heat are cheap. But there is still the question of how the programme will be paid for.

Sadler says the report has looked at funding the conversion under the same regulatory asset base model used to pay for the existing gas and electricity networks.

This, he argues, would minimise costs and spread them across all consumers over a number of years: “The principle is that any large-scale scheme is part of a UK ambition and ultimately a global ambition to meet climate change obligations and it’s not appropriate to effectively penalise the people in the first area to convert just because of where they live.”

On this basis, the financial impact of the first phase of the project would peak in 2034 when it would add 7 per cent to the typical annual energy bill.

He says it is up to the government whether to socialise the costs further by funding all or part of the conversion through taxation.

One of the main aims of the H21 programme is to provide ministers with the evidence necessary to make a policy decision on hydrogen conversion in the early 2020s.

“The only reason we can’t actually make a policy decision now – not withstanding political will and short-term politics – is because we’re still in the process of gathering the remaining pieces of safety evidence to confirm that 100 per cent hydrogen represents a comparable risk to natural gas or town gas,” Sadler explains.

He says the next stage of the programme will be to undertake the front-end engineering and design for the conversion over a period of three to four years starting in 2019. This should enable a final investment decision to be made by 2023.

Live trials are also likely to be conducted in “very small areas” over the winter of 2022/23 to “really underpin the economics and just give a bit more confidence in the end-to-end system.

Sadler is keen to tout the strong local backing for the scheme, noting that numerous local authorities have written letters of support: “There is a collective will from the North for this to happen”.

He says the project would not only deliver benefits in terms of climate change and air pollution, but also “create tens of thousands of jobs for decade after decade” in one of the UK’s least economically productive areas.

For ministers looking to address the economic imbalance between the north and south, this could present an attractive offer.

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