Across Europe, natural gas remains the main source of energy in households and industry. But the push to meet carbon reduction targets by replacing natural gas with less polluting hydrogen is creating sharp contrasts in politics and sparking political debate.
In Britain, the government is considering plans to mix hydrogen with natural gas to deliver a less polluting flammable fuel to most homes in the foreseeable future. Around 20 per cent of all carbon emissions in the UK come from residential buildings – mainly natural gas used for heating and cooking.
Later this year, UK Energy Secretary Grant Shapps will decide whether to introduce a blend of up to 20 per cent hydrogen into domestic national gas supplies in the second half of this decade, a blend generally considered safe for hydrogen distribution through existing networks. .
In addition, the UK is considering proposals to make all newly installed domestic boilers ‘hydrogen ready’ – capable of running on full hydrogen – from 2026.
As well as helping to deliver cleaner burning fuels to homes, this stepping stone could also ease pressure on future electricity supplies from the expected introduction of heat pumps and electric heating in UK homes – 85 per cent of which are currently heated by gas boilers. .
However, this British strategy is at odds with the approach taken in Germany. There have been proposals for a major ban on gas boilers in new and replacement heating systems from next year exposed April and split the ruling coalition.
Supporters of the new German laws are putting most of their faith in heat pumps — generally seen as the leading short-term alternative to natural gas for home heating — rather than a rapid transition to blended or “clean” green hydrogen, which is produced by using renewable energy to split water molecules.
Jan Rosenow, European program director at RAP, an independent energy think tank, is also skeptical about the suitability of green hydrogen for heating homes – although he sees the gas as key to decarbonising the wider energy supply.
“The good news for the green hydrogen industry is that we need a lot of it,” he says. “But the priority should be where it’s clear it’s a good use of hydrogen.”
His an overview of 32 studies from around the worldpublished last October, concluded that “compared to other alternatives such as heat pumps, solar thermal and district heating, the use of hydrogen for domestic heating [was] less economical, less efficient, more resource-intensive and associated with greater environmental impact”.
Instead, it advocates favoring green hydrogen as a replacement for large volumes of “dirty” fossil fuel-derived hydrogen in existing industrial processes. These include fertilizer production and heavy industry such as steel and cement production.
It also points to seasonal energy storage – converting excess renewable solar and wind energy through hydrolysis into green hydrogen, which can later be burned to generate electricity. Although this involves large energy losses, Rosenow argues that “seasonal storage is not so bad.”
British gas companies are pushing ahead with feasibility trials that envisage a growing role for fuel stocks for both green and blue hydrogen – where carbon capture and storage is used to mitigate the pollution caused by converting it from natural gas.
Regional gas distributor Cadent hopes to carry out a government-backed local trial of 100% hydrogen home heating in Whitby, Cheshire, while Northern Gas Networks aims to carry out an equivalent trial in Redcar, North East England, from 2025.
Cadent has already run a test called HyDeploy with Keele University, which has shown that a 20 percent mixture of hydrogen in natural gas can be used to heat homes and buildings with the potential to reduce carbon emissions without replacing gas appliances or pipes.
Jake Tudge, director of corporate affairs at National Gas, which runs the backbone of the UK gas network, estimates that half of UK homes, if properly insulated, could be suitable for heat pumps. But it insists on other alternatives to natural gas – including hydrogen – to heat the remaining housing stock.
It suggests that the requirement to install “hydrogen-ready” boilers when replacing obsolete units from 2026 could lead to “no regrets” investment in homes unsuitable for a heat pump – if hydrogen-only units achieve price parity with conventional boilers. .
Industry estimates put the cost of hydrogen-ready boilers at around £2,000, compared to £9,000 to £15,000 for an air-fired heat pump.
According to a UK parliamentary report published in December, there is no clear consensus on the “optimal mix” for deploying hydrogen, heat pumps, heat networks and other hybrid solutions to decarbonise heating.
However, on cold, dark and still winter days when wind and solar power shut down, stored green or blue hydrogen could be replaced with natural gas to boost low-carbon electricity supplies. However, this will require a significant reconfiguration of gas networks and the modernization of gas turbines in power plants.
“We need huge amounts of energy backup with hydrogen storage and hydrogen gas turbines, and if you want to decarbonize industry, hydrogen plays an important role for those who can’t electrify,” says Tudge. “Hydrogen has a huge storage role in the system.”
James Earl, director of gas at the UK’s Energy Networks Association, which represents the country’s biggest electricity and gas distributors, says green and blue hydrogen will be needed to meet net-zero ambitions.
“Looking out to 2050, there’s no way to do that without some form of ‘green’ gas in the mix,” he says. “We will all have to embrace change – whether it’s a shift to hydrogen, increased electrification or a combination.”
National Gas’ Tudge agrees: “We have to use every tool in the box.”