Why hydrogen won’t be a major solution to decarbonising domestic heating
Winter has come are dreaded words in the Song of Ice and Fire books and in the real world. In the former it is due to the risk of an onslaught of legendary monsters. In the later due to the very real massive energy bills that will condemn many to death and around 7 million to fuel poverty. To make future winters less dire, preparation is needed through decisions on infrastructure. In the Song of Ice and Fire this takes the form of a massive wall. In the real world this takes the form of energy systems that deliver affordable central heating and energy efficient homes for us to live in. The government in both cases have adopted a policy of neglect and infighting instead of sensible action. A recent announcement of a consultation mandating boilers are hydrogen ready by 2026 may indicate more years of confusion and dithering leading to us all freezing.
The UK is unusually dependent on fossil gas for keeping residential buildings warm (92% of heat generation compared to the German 46%). It also has a housing stock that is leakier than the European average, by approximately 1 degrees Celsius of heat loss. Finally, it’s proximity to the poles means that the country is relatively cold in winter.
Fossil gas has also recently become extremely expensive, with UK gas spot rising from approximately 85p/therm in September 2021 to 435p/therm a year later. The government – after letting energy bills double – has temporally frozen them and cack-handedly delivered support for the most vulnerable, costing £57 billion. Many people are, however, still at risk of cold-related deaths. The only sustainable way out of this is to heat homes using a cheaper energy source.
Fossil gas is exasperating the weather problem by ensuring more extremes of climate putting pressure on a building infrastructure not constructed to cope with extremes of -10 degrees and +40 degrees. While most UK sectoral Greenhouse gas (GHG) emissions have been trending downwards, heating emissions fell 9% between 1990 and 2017 and appear subsequently to have risen. In 2019 the chair of the Committee on Climate Change (CCC) concluded that without action on housing, “there is no way in which the UK can meet the legally-binding climate change targets”.
Solution 1: Energy efficiency
The first solution to this is less energy to be used to heat homes. This could involve turning down temperatures, but for many people the only way this is possible is to live in a more energy efficient building. The options from here are mass migration to central Europe, or improving the housing stock we already have. The coalition government inherited a number housing efficiency schemes including the zero carbon standard and the Energy Compony obligation (ECO) that drove insulation at a rate of over 2.2 millions houses in 2012.
If the government had retained these programmes it would have saved the UK £1.1bn in 2022, with the poorest feeling most of the benefit. However, under pressure over the cost energy from Ed Miliband, Cameron cut the ECO and following the 2015 election Osborne killed the Green Homes Standard.
Since 2012, insultation rates have fallen between 66-90%. Successful schemes – such as the Green Deal policy – were so poorly managed that the National Audit Office concluded that it increased the cost insultation around the county. Boris Johnson’s and Kwasi Kwarteng’s Green Homes Grant was subcontracted to a US-based private firm and distributed less than 15% of the money and less than 10% of the intended grants and may have led to job losses in the sector.
Somewhere someone is blaming Ed Miliband for this.
I have been unable to find anyone arguing energy efficiency improvements are a bad thing. So we can all be hopeful that the latest and more concerted attempt to restart the UK energy efficiency improvement launched this year meets more success. However, there is also a need to look to the energy source available for heating.
Solution 2: Heat networks
Heat networks supply heat from a central source to consumers often via hot water pipes. They are usually used in flats, or high-density areas.
The carbon intensity of heat networks depends on the source of the heat. Islington uses waste heat from the London tube network, but others may use a gas, or even coal boiler.
Heat networks are only an option in places with high population density and the correct infrastructure. Plans in Oxford seem to have stalled, and even the industry body thinks that heat networks could only provide 17% of UK heat demand.
In 2019, the government announced £19 million to provide five low carbon heat networks. The CCC sees development of this as a low regret option. This is one of few areas which the CCC sees the government as on track to achieve net zero by 2050 – though it notes that most of them are from high carbon energy sources and that the government is targeting heat network delivery 40% lower than the CCC says is needed in 2035.
More progress could be made, but by in comparison to the mess of energy efficiency policy, this is a relative success story. However, heat networks are not a large scale solution. More progress could be made but no one thinks this will be more than a part of the national solution. In summary they are a good thing that we could do with more of, but they are not a matchwinner without other solutions.
Solution 3: Heat pumps
Heat pumps use electricity as a power source to draw ambient heat from air, ground or a combination of both. While unusual in the UK globally they make up 10% of global heat demand and are on the rise. The EU has seen 26% increase in sales of heat pumps in the past two years and has a target of heat pumps providing 40% of heating for all residential buildings by 2030.
Heat pumps have the advantage of being highly efficient: the average gas boiler is approximately 96% efficient, whereas heat pumps generally are between 300%-400% efficient, thereby generating three times the heat energy than the electricity put in. Unlike gas boilers, they take longer to heat large areas, but can run constantly and in many cases also provide cooling. Concerns that they operate poorly in lower temperatures have been addressed by Norway being an enthusiastic adopter of heat pumps with 1 for every 4 people by 2025.
However, heat pumps require an entirely new heating system installed and the UK – through inconsistent and indecisive policy – has hampered the development of supply chain. The cost of installation is still as high as £10,000 per household, though this is failing rapidly. CCC modelling suggests that this cost would be offset by higher efficiency, lower cost power and longer lifespans compared to our current gas boilers. The Office for Budgetary Responsibility chimes in to suggest that this will have net payback to the economy by 2045. As the UK’s electricity mix is less carbon intensive than the fossil gas, it would radically lower emissions.
Solution 4: Hydrogen
Like fossil gas, hydrogen – when burned – can produce heat. It has the appeal of operating similarly to fossil gas. Hydrogen could be blended with the gas grid to slowly develop the market. At low shares of hydrogen in the gas system, components and piping does not need to be replaced. This advantage disappears as more hydrogen enters the gas grid, hence the need for a consultation on hydrogen ready boilers.
Another serious barrier is how hydrogen is produced. I wrote previously in Bright Green about this. In summary, most hydrogen is produced using gas or coal, which is more carbon intensive than just using the gas. There is a small developing green hydrogen sector, where electricity passed though water creates hydrogen. Unfortunately, this process is highly inefficient, at approximately 46%. In the same way that heat pump efficiency ensures that it will result in a saving compared to the current fossil gas dominated heating system, hydrogen’s inefficiency suggests the opposite costing, 73% more than providing the same power with heat pumps.
The UK government has been keen on hydrogen, seeing it as an economic opportunity. The government has targeted 5GW of low carbon Hydrogen by 2030, a maximum of 42 TWH. Fossil gas provided 299 TWH to homes in 2020. Astute readers will notice the chasm between those two numbers.
For the foreseeable future, much of the hydrogen will have to come from high carbon sources or imports. As to the feasibility of imports, the EU capacity for green hydrogen production is approximately 1GW.
Wide use of hydrogen in UK heating would draw it away from sectors where it is the only low-carbon replacement. While 2019 CCC report suggested more research into hydrogen needed to be done but that it could play a role, almost every piece of evidence since then has raised more red flags about hydrogen.
The CCC review of the government heat strategy in March 2022 mentions hydrogen 56 times (heat pump 107, heat network 151) and it is relegated to the role of other with ‘potential for it to play a role in mid 2020s’. A review of scientific evidence and modelling into hydrogen heating found it was – even under favourable conditions – less efficient than electricity leading, to its author commenting to the New Scientist, “It is difficult to think of any circumstances in the decarbonised future when it would make sense to use hydrogen for heating”. The House of Commons Science and Technology Committee report on hydrogen in December 2022 led with the conclusion ‘hydrogen is not likely to be practically and economically viable.” To top it all off, Cornwall Insight added a note to their price cap predictions that hydrogen could increase bills by 90%.
The question therefore remains why in the last days before Christmas 2022 the government announced a consultation into making all new boilers hydrogen ready by 2026.
Why back hydrogen heating
It would be a disservice to the government to suggest that there is not a case for hydrogen ready boilers. The CCC included as a recommendation in a 2019 report that the government considered mandating them by 2026 and suggested in one pathway that hydrogen could meet 11% of UK heat – though this seems to mainly be focused on areas where owing to the poor nature of construction it will be inefficient to electrify or add to district heating. However, policy has been moving in another direction.
In a surprise to civil servants working on the issue in 2019, the then Chancellor of the Exchequer Phillip Hamond used his budget speech to commit the government to backing heat pumps as a solution to low carbon heat, though oddly for a budget speech he announced no attached funding. Subsequently, the government set a target of 600,000 heat pump installations by 2028 and 50% cost reduction. It took until 2022 for the government to put money behind this with the then Chancellor of the Exchequer Rishi Sunak declaring 0% VAT on heat pumps, funding of £5,000-£6,000 for heat pump installation, alongside capital grants to the industry in a package worth £450 million.
For context, the CCC estimated that in order to reach net zero by 2050 900,0000 heat pumps would need be installed annually from 2028 and £12bn would need to be invested into UK building stock each year to 2050.
This is merge progress compared to government targets, or by the progress made across the Channel. By 2026 Germany, the Netherlands, Belgium, Slovenia, Greece and Ireland will all ban gas boilers. France and Austria have already done so. Italy is offering to cover 110% of cost on installation of heat pumps even the USA has new funding to cover 80-100% the cost of installation.
The consultation into hydrogen boilers suggest the government is still considering hydrogen for home heat. This goes against the direction of travel of all our near neighbours (hardly a surprise for a Brexit government) and its own direction of travel.
A sympathetic reading is that the government is merely exploring options and is in line with CCC guidance – just about. Hydrogen could play a role for a limited number of homes. However, given the decade of mess for home heating and the still under-ambitious policy goals, sympathy may be unwarranted.
When winter arrives in the Song of Ice and Fire books, the long-term neglect of the wall leaves an opening for monsters. The solution may be a dragon. Those freezing in the UK this winter can tell you the monsters are already here. A dragon is unlikely to appear and help them. It is on the UK government to throw off its legacy of missed opportunities and set a firm direction so we can get warmer. This consultation seems unlikely to contribute to this.
PS. We hope you enjoyed this article. Bright Green has got big plans for the future to publish many more articles like this. You can help make that happen. Please donate to Bright Green now.
Image credit: Raimond Spekking – Creative Commons