Liverpool and Manchester are to be the testbed for an ambitious £600m project aiming to solve the thorny problem of how the government cuts the carbon footprint of the gas that heats most of Britain’s homes.
Cadent, which runs the connections to half of the UK homes on gas, hopes to undertake a pioneering trial in the 2020s using hydrogen as a cleaner alternative to methane in pipelines across the region.
Formerly known as National Grid Gas Distribution Limited, the company will focus on industrial users in sectors such as chemicals and oil refining, because using 100% hydrogen requires new boilers to be installed.
But some of the hydrogen will also be blended with methane and piped to millions of homes in Liverpool and Manchester.
Cadent believes mixing in hydrogen to account for about a fifth of supplies could be done without harming domestic boilers and cooking equipment, such as hobs.
“We want to help demonstrate a pathway to the decarbonisation of heat that is not only lowest cost to UK plc but is minimally invasive to customers. Any government policy which requires customers making different choices is very difficult,” said David Parkin, the engineering director at Cadent.
Hydrogen had an advantage over alternatives such as local heat networks or heat pumps run off electricity, he argued, because many people had a “strong emotional attachment” to gas.
The existing gas network also meant there was a ready-made way to distribute it.
But to fully switch to hydrogen, the 26m gas boilers in the UK would need to be swapped for hydrogen-compatible models. About 85% of homes are heated by gas. “It does require changes in people’s homes and it is likely to be expensive, so we are looking at a number of alternative pathways,” said Parkin.
That is the reason for the Liverpool-Manchester scheme’s initial focus on industrial users. The area was selected because it has a population of 5m and represents about 11% of Britain’s industrial sector. As well as reducing the number of boilers that need to be converted, industrial heat demand is relatively steady compared with the fluctuating demand from homes, which would probably require the company to build hydrogen storage, an additional cost.
The carbon savings will come from the way the hydrogen is produced. It will be made from natural gas using a method known as steam reforming, but Cadent’s plan is to capture the carbon monoxide and small amount of carbon dioxide generated during the process.
The captured carbon will be pumped using existing pipelines and stored in Hamilton gas field in the Irish sea, which is due to be decommissioned in the early 2020s – a cost that could be avoided if the facility is repurposed as a repository for carbon.
Whether the project goes ahead depends on tests underway on a private gas network at Keele University to identify how much hydrogen can safely be mixed in with methane for heating.
An investment decision in the early 2020s would mean construction starting in the middle of the next decade.
As a regulated monopoly, Cadent’s costs would ultimately be borne by energy bill payers, though the regulator Ofgem would have to approve the anticipated £600m capital cost.
Other parts of the UK exploring hydrogen for heating include Leeds, where Northern Gas Networks has worked with the government on a feasibility report that concluded a national switchover was viable but would cost £2bn for Leeds and billions more to implement across the UK.
Jonathan Marshall, an energy analyst at the ECIU thinktank, said: “This [Cadent] project shows at last some progress towards decarbonising heat, which seems to be perennially avoided as an issue. We’ve seen progress on [emissions from] electricity and transport – heat is the final piece of the puzzle.”
Addressing public perceptions and concerns would be key. “The gas network is massive, hundreds of thousands of kilometres of pipes, so you’d have to do[a switchover from methane to hydrogen] gradually to make sure nothing goes wrong,” he said.