Will the UK’s hydrogen blending experiment pave the way for a low carbon future?

Despite its widespread use in certain sectors, most hydrogen production remains heavily reliant on fossil fuels. The availability of low and zero-emission hydrogen sources is currently limited, and production must increase significantly for utilities to be able to rely on hydrogen as a key component of their sustainability efforts.

To promote production of low-carbon hydrogen, the Department for Energy Security and Net Zero (DESNZ) recently released a consultation asking for a response from industry participants detailing their opinion on the case for hydrogen blending into the GB Gas Distribution Networks.

In the second instalment of this hydrogen deep-dive (read the first here), Francesca Gabriel, Senior Consultant, and Tom Rudgard, Management Consultant, explain the process of blending hydrogen with natural gas, and the UK-specific implications of this experiment in terms of customer, environmental, and long-term net zero benefits.

What is hydrogen blending?

To grasp the concept of ‘blending’, we must first examine it in the context of natural gas.

Gas power stations play a pivotal role in electricity generation, and gas also serves as an essential component of space heating for homes, offices, hotels, and restaurants. In 2019, gas accounted for nearly two-thirds of total domestic energy demand.

However, natural gas is a fossil fuel, emitting CO₂ upon combustion. Therefore, the UK must embark on a concerted effort to reduce its reliance on natural gas as much as possible by 2050 to achieve its emissions targets.

Hydrogen blending provides an option for gas networks to reduce these emissions. Green hydrogen, produced from renewable sources like solar, wind, or biomass, has a low carbon intensity. By blending green hydrogen into the gas pipeline at injection points, the overall carbon content of natural gas can be reduced.

The maximum hydrogen ratio that modern residential end-use appliances can safely handle is still under research. Proposed public trials are limited to small scale villages with a maximum blend of 20% hydrogen to 80% natural gas.

The emissions savings from using a hydrogen blend result from two factors: the carbon intensity of the hydrogen production method and the carbon difference between burning a 20% blend versus 100% natural gas. Blending hydrogen produced from non-renewable sources (e.g. produced from natural gas or coal) unsurprisingly provides little to no carbon reduction. In 2022, 165 Megatons of CO₂ was produced from natural gas. A 20% green/low carbon hydrogen blend could reduce this by 7%, resulting in a 11.5MT decrease of CO₂ released. This is equivalent to taking 8 million cars off the road.

What are the UK-specific considerations for hydrogen blending?

If the UK is to diminish uncertainty for investors in the hydrogen market, then government backing is essential to develop strong infrastructure design. Reducing risk by having the government act as a reserve off-taker of produced low-carbon hydrogen is a key part of the DESNZ consultation proposal. Whilst the intention is to stimulate a low-carbon hydrogen economy, there are considerations as to whether this is the right approach.

1. Environmental benefits of blending hydrogen for domestic heating aren’t clear. There are doubts regarding domestic heating being the most ideal application for low-carbon hydrogen. This scepticism stems from the fact that hydrogen possesses a calorific value roughly one-third that of natural gas. Consequently, by blending hydrogen with natural gas, the resultant gas will have a lower energy content per unit volume. Recent experiments involving the blending of 20% hydrogen with natural gas for use in a combustion turbine, with the aim of maintaining gas volume, have yielded only a 7% reduction in CO₂ emissions. If green hydrogen isn’t used, then the environmental benefits become even more limited.
2. The decision to abandon the hydrogen trials for domestic heating in Whitby and Redcar this year, driven by resident concerns regarding safety, effectiveness, supply, and cost, suggests hydrogen is unlikely to find a substantial role in household heating. Moreover, there are alternative technologies, such as heat pumps, which offer superior performance and have gained traction in the option to decarbonise homes. Public acceptance of the ‘hydrogen economy’ can hinder large-scale deployment and the raised gas bills for the customer (even during a trial) in a time of raised cost-of-living, does not impact public perception positively.
3. The government must consider how this blending consultation would benefit the net zero transition in the longer term. It acknowledges that this would be a transitional blending scheme to reduce emissions in the near term. However, they should consider how this would artificially extend natural gas usage, embedding it in the future energy mix. There is a high risk of creating a broken hydrogen blending market from the start, that doesn’t deliver on environmental or customer return on investment.

What are the most impactful use cases for hydrogen?

Use cases of hydrogen exist in industries that have limited alternative options to fossil fuels. The development of a hydrogen economy is crucial to meeting long term net zero targets for these industries. There are two connected opportunities in decarbonising these industries, firstly low-carbon hydrogen replacing currently used grey and brown hydrogen, and secondly in applying new decarbonisation technologies. It should be considered if these use cases would be a better use of hydrogen to help the UK achieve its Net Zero goals, over utilising hydrogen for heating.

Grey hydrogen is produced from fossil fuels through steam methane reforming (SMR). It’s the most common method of hydrogen production but has a significant carbon footprint. The chemicals, fertiliser and refinery industries already produce and uses 94 million tonnes of grey hydrogen annually, which is 3% of global final energy demand. There is a clear opportunity in these industries by focusing on replacing grey with green hydrogen.

The decarbonisation of steel production is another significant application. In 2020, total direct emissions from the sector were around 2.6billion tonnes, representing between 7% and 9% of global CO₂ emissions.

Notably companies such as H₂ Green Steel have recently secured funding of $1.6 billion to construct a hydrogen-based steel manufacturing plant in Boden, Sweden, which holds the potential to reduce emissions by 95% compared to traditional steelmaking.

The infographic below is from the first blog in this series, and provides further information on use cases:

What’s the key takeaway on hydrogen blending?

Whilst blending is an option the government is investigating, we must consider the ramifications and benefits of an infrastructure scheme such as blending. Whatever the strategy, we must transition away from gas as well as other fossil fuels to meet the UK’s net zero commitment by 2050. The UK needs to prioritise low-carbon hydrogen production and for the most effective use cases to see the largest carbon reductions.

Don’t miss our next instalment, in which we’ll explore the use of digital twins in hydrogen production.

Capgemini and hydrogen.

Our industry experts have authored several in-depth reports on hydrogen and its role in decarbonisation. Download them here:

• Unlocking the hydrogen age
• Low-carbon hydrogen: A path to a greener future
• The path to low carbon hydrogen

You can also hear some of our global perspectives on the topic, over on our YouTube channel:

• Why low-carbon hydrogen is a sustainable solution
• Capgemini Invent Talks: The path to a green hydrogen future
• Creating a hydrogen marketplace

To see our hydrogen expertise in action, read our relevant case study on how we helped take Hyliko from concept to company to provide freight transportation companies with a more sustainable, carbon-negative alternative. https://www.capgemini.com/news/client-stories/hyliko-powers-freight-transport-with-hydrogen/

Get in touch with our experts:

Francesca Gabriel or connect on LinkedIn if you have a specific hydrogen-related challenge or want to explore options for decarbonising your business.
Tom Rudgard, UK Hydrogen SME
Jack Taylor, UK Hydrogen SME
Melissa Leung Pah Hang, Climate Tech Lead
Nicole Alley, VP, Head of Renewables