Heat is a hot topic in the energy sector. But there are fears that a lack of political will is blocking one of the most likely paths to this decarbonisation – hydrogen.

The UK is doing a lot on decarbonisation. For one thing, the country has a target to reduce emissions by 57 per cent by 2030 against a European Union goal of 40 per cent. It is committed to an even more ambitious 80 per cent reduction by 2050. However, most decarbonisation up to this point has concentrated on the relatively “low-hanging fruit” of electricity generation. Very little progress has been made on the decarbonisation of heat.

The plan – for better or worse – was to decarbonise electricity and then electrify heat, as well as other sectors such as transport. However, it may not be that simple. At approximately 300GW, aggregate peak demand for heat is roughly five times greater than that for electricity, according to Ofgem. Currently, 80 per cent of UK homes are heated by gas, with heat accounting for around one-third of UK CO2 emissions.

“The volatility of heat demand is enormous and extremely difficult to deal with,” says Malcolm Keay, a senior research fellow from the Oxford Institute for Energy Studies. “There is no real alternative at the moment to fossil fuels for seasonal storage. The easiest way to do it is by great big piles of coal – that’s not acceptable any more, we have to move on to something else.”

Speaking at the Low Carbon Networks and Innovation conference – held in Telford by the Energy Networks Association – Keay argued that hydrogen is key to the decarbonisation of heat. However, he warns, from a political perspective it is the “wrong sort of technology”.

Renewable heat

Alternatives are few and far between. “Energy efficiency is certainly going to be an option in terms of the decarbonisation of heat, but there is still a question about whether it can deliver on the scale required – an 80 per cent reduction or 100 per cent reduction,” says Keay. “Renewable heat brings big environmental and economic problems. If anything, there are moves at the moment to reduce the amount of renewable heat in the UK because of the impact of wood burning.

“District heating is, frankly, pretty expensive, and it’s not really clear if it’s compatible with the move towards energy efficiency because there is so much capital cost involved – if heat demand is lower, the result will be a higher cost for the individual users of heat.

“Heat pumps have been mentioned as a large part of the solution, but frankly they’ve been pushed for a long time and have not proved very successful in consumer terms or in economic terms. I think it’s rather optimistic to see them as a part of the solution.”

“Hydrogen could, in principle, form part of a sustainable energy economy,” he says, adding that the fuel could complement intermittent renewables, it could be used in transport – it is the current frontrunner for freight transport – and it could be used in fuel cells. “If that were the case, you might conceivably be able to achieve whole-system co-ordination more easily, by using home fuel cells to provide heat and generate electricity,” he says.

The existing gas pipeline system is, to a large extent, already compatible with hydrogen, because the distribution mains are in the process of being converted to polyethylene. What’s more, the consumer impact would be “relatively manageable”, compared with other options. “People could use basically the same equipment. They might have to replace the burners in that equipment in the way they did when the UK moved over from town gas to North Sea gas.”

Keay asks whether heat decarbonisation – which is inevitably going to affect gas – can be managed more smoothly. One of the main points is that decarbonising heat via electricity is pretty difficult. He says: “I’d argue that the main alternatives would also present problems. One of the frontrunners at the moment – and I agree it’s not the only one – is using hydrogen from methane reforming.” But is a hydrogen solution deliverable?

Bad politics

Keay believes that politically the argument for hydrogen “doesn’t work”. “I’m afraid the policy challenge is far and away the biggest one, and that’s what has to be looked at. It’s not enough to look at the pure economics and the technical aspects of it if a solution will not work politically.”

He adds: “From a political perspective, it’s the wrong sort of technology, it’s got the wrong sort of economics and it’s the wrong sort of policy. What it’s competing with – unless the government intervenes and forces consumers to change – is gas. And there’s a huge gap [in cost].”

The Oxford Institute for Energy Studies carried out research looking at the ways in which the “green gas” option might be taken forward in order to emerge as a “fully-realised policy option”. The group suggests it could only be delivered on the basis of a “major strategic decision by the government” and a “clear vision of the future low-carbon energy system”.

“What’s happened in the electricity industry has basically turned the whole industry upside down and is going to continue to do so. There is at least a prospect that the same is going to happen with gas,” says Keay. “I would argue that electricity markets are broken; I would also argue that regulation is broken. The original regulatory settlement was based on the assumption that there were four “bits” to electricity – generation, transmission, distribution, and supply – that is really not the case anymore.

“There is a huge overlap between transmission and distribution and generation. We’ve seen that, for instance, with the interconnector competing in the capacity market, and with UKPN investing in flexibility as an alternative to distribution strengthening. Dieter Helm [an energy expert and government adviser] has suggested the whole regulatory system for distribution should go out the window. Ofgem is looking at the supplier hub principle. Basically, the whole regulatory system is broken.”

He says the main approach to decarbonisation in the UK has been by encouraging low-carbon generation. “Government started this process by thinking: well it’s just a matter of slotting in a low-carbon source for another – it’s not. It changes the whole dynamic of the system and everything else. That is going to happen in other sectors too, but we don’t know how far and how fast and in exactly what way.”

Now, Keay argues, the country has ended up in a state of “ideological limbo” as far as energy policy is concerned. “Governments are, in principle, committed to markets, but they have to keep intervening in practice, both to meet their carbon objectives and to offset their earlier interventions.”

Oxford Institute for Energy Studies’ work concluded that it is, therefore, “difficult to see a clear way forward for the technology”, given that, in the present state of uncertainty, a clear vision of a hydrogen-based energy economy is needed.

However, others in the energy industry are more optimistic about the prospects for hydrogen. Network companies are doing a lot of work on the feasibility of using the fuel.

In a column for Utility Week, Northern Gas Networks chief executive Mark Horsley says the opportunity to repurpose the gas network to transport a zero-carbon gas such as hydrogen could be “transformational” for heat, making this alternative gas a cornerstone of a diverse and sustainable low-carbon energy mix. “The UK government has recognised hydrogen as a key pathway to decarbonising heat and there are currently several significant hydrogen projects under way in the UK testing different scenarios and advocating various approaches.”

Work in progress


The H21 Leeds City Gate project is a study being carried out by Northern Gas Networks and Wales & West Utilities to determine the feasibility, from both a technical and economic viewpoint, of converting the existing natural gas network in Leeds to transport hydrogen.

The project has been designed to minimise disruption for existing customers and to deliver heat at the same cost as natural gas. It has shown that:

  • The gas network has the correct capacity for such a conversion, which would reduce heat emissions by around 73 per cent reduction.
  • The network can be converted incrementally to minimise disruption to customers.
  • Minimal new energy infrastructure is required compared to alternatives.
  • The existing heat demand for Leeds could be met via steam methane reforming and salt cavern storage using technology in use around the world today.


HyDeploy is an energy trial being hosted at Keele University, Staffordshire, to establish the potential for blending hydrogen into the normal gas supply.

The project is funded by Ofgem’s Gas Network Innovation Competition, Cadent and Northern Gas Networks. Subject to Health & Safety Executive approval, the aim is to run a year-long live trial of blended gas starting in 2019.

In summary, the research aims to:

  • Establish and demonstrate the level of hydrogen blended with natural gas that can be distributed and used safely in the UK (up to 20 per cent).
  • Provide practical evidence that a hydrogen blended gas can be delivered and used without disruption to gas customers.
  • Collate data about how a sample of current UK gas appliances work with hydrogen blended gas.
  • Inform the national debate over routes to ­decarbonisation.


The £25 million Hydrogen for Heat Programme – commissioned by the Department for Business, Energy and Industrial Strategy – will look at the feasibility of converting a small village or estate to use hydrogen for cooking and heating instead of natural gas.

The Arup-led consortium will explore the practicalities of using the zero-carbon gas in homes and will facilitate the design and manufacture of new appliances such as fires, cookers and boilers, for both domestic and commercial use.

The project, expected to run until March 2021, will explore public attitudes to changing to hydrogen. Ultimately, it will have laid all the groundwork for the demonstration of a pilot project in a village or small town.

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