Grey or Green Hydrogen

Protium explores green hydrogen production in a case study of the Protium Project Pioneer 1, exploring carbon storage and net zero possibilities in energy

Hydrogen is widely seen as a critical component of a net zero future and has a key role to play in decarbonising sectors such as heavy transport and industrial processes.

It has seen a recent boom in interest, driven by the urgent need to tackle climate change, technological improvements, and the challenges faced by industries in decarbonising through electrification.

Is hydrogen the future of energy?

Hydrogen is already commonly used in industries, particularly in chemical processes. The dedicated production of hydrogen as an energy carrier is an emerging trend.

The speed by which demand has grown is nothing short of phenomenal, and it is only increasing, but this has led to two important questions – is it a sustainable solution, and where does it come from?

While it is very encouraging to see a desire for a greener future, it is important to consider how hydrogen is produced to ensure that there is a positive difference being made to a net zero future.

Today, most of the hydrogen in the UK and around the world is produced through a process called Steam Methane Reforming.

As the name suggests, methane (made from natural gas) is broken down by steam and heat into hydrogen and carbon dioxide, the latter being released into the atmosphere. Due to the emissions associated with this, it is often labelled “grey hydrogen”. If all hydrogen for future “green projects” was from “grey” sources, this would simply shift emissions from the point of use to the point of production.

The opportunities of carbon storage

Methods to capture and store carbon, commonly termed CCS for short, are being developed. When CCS is added downstream of the steam reforming process, the hydrogen can be labelled “blue”. However, this process is still not a zero-emission procedure, as not all carbon can be captured.

The best zero-emission method for hydrogen production is called electrolysis, where water is ‘split’ into its constituent parts using electricity. If the power is generated by renewables or nuclear power, there are no carbon emissions, and the hydrogen can be labelled “green” because there are no carbon emissions.

Currently, the availability of green hydrogen is very limited, but this is fast changing with companies like Protium leading the charge.

Pioneering green hydrogen facilities and projects

There is a growing shift taking place towards green hydrogen, with production facilities being planned and developed across the UK.

Protium is one of the companies leading the way, having unveiled its first operational electrolyser earlier this year and with more projects already in development.

The Protium Pioneer electrolyser unit is the largest installation of Enapter AEM technology in the UK. Pioneer 1 consists of 40 Enapter electrolyser modules that can produce over 40kg of hydrogen per day. This is the equivalent to powering 13 cars for 350 km.

The electrolyser load can be adjusted to match the fluctuations and intermittence of the renewable power, while the hydrogen produced can be stored as a gas or liquid and consumed as and when the user needs it. Therefore hydrogen will be so important in a net zero future.

However, developing and implementing this kind of infrastructure is not without its pitfalls.

The impact of energy supply chain disruptions

The effects of the pandemic and ongoing war in Ukraine, coupled with a surge in demand for green hydrogen products have put a squeeze on the supply chain in nearly every area involved in the mechanical manufacturing of products.

There is evidence currently of costs increasing over 30% as well as lead times increasing over 100% in the space of a few weeks. From a developer’s perspective, this has put pressure on getting orders placed early and managing contracts to prevent cost overruns.

Managing inherent hydrogen safety

A key aspect of any project is ensuring that inherent safety is achieved within the design. By its nature, hydrogen is more flammable than natural gas. However, being a much lighter molecule, it also disperses faster.

Therefore, achieving adequate ventilation for a hydrogen system is a key challenge to prevent hydrogen from reaching its flammability limit (4% v/v in air). To achieve an inherently safe site, many key pieces of equipment should be deployed outside of containers to ensure maximum natural ventilation and to prevent hydrogen build-up.

Additionally, the hydrogen container for Pioneer 1 fitted with forced ventilation, ensures hydrogen can never reach its flammability limit. Explosion-proof equipment should also be used where needed.

Stakeholder engagement

Green hydrogen is a nascent industry, and many key stakeholders are unfamiliar with hydrogen in contrast to other fuel sources. The key takeaway is that educating stakeholders and the public about the benefits of green hydrogen as well as the setbacks, should be encouraged.

This will speed up the acceptance of green hydrogen and ultimately allow the general populace to appreciate the need for a quicker move towards a net zero emission future.

Extending the development of the UK hydrogen market

Project Pioneer 1, as well as all green hydrogen production projects, show the ongoing development of the UK hydrogen market.

Project Pioneer 1 demonstrates the importance of scaling up in the market from a smaller project. It also proves that with the required technology and processes, a blueprint can be created to aid in planning for larger-scale green hydrogen projects.

This means that outcomes will be delivered more quickly not only for companies like Protium, but, more importantly, for the wider hydrogen market.

Projects Pioneer 1 demonstrate that green hydrogen can be a viable decarbonising solution and it is a major step forward towards a net zero economy.

Source: Open Access Government