A head start and big prizes at the finish

Matthews has worked in energy for more than a quarter of a century and is a partner at ERM, a global environmental consultancy that’s played a key role in setting up Dolphyn Hydrogen. He argues that sending hydrogen back to shore, along pipes, is more cost effective than getting electricity back to land. There’s no loss along the way, you need relatively low pressure and excess hydrogen can be stored in tanks or wider pipes, not expensive batteries. Plus you’re making the most of strong winds.

“With this technology, we’ll produce green hydrogen at the same cost as natural gas,” says Matthews. “Offshore hydrogen is more economic than most people believe, if you can get to scale quickly.”

Plus, he adds, it means producers don’t get tangled up with grid connections, which can slow down ambitious projects and lead to missed decarbonisation targets.    

There are other advantages to offshore hydrogen. Amey Karnik, head of industrial decarbonisation at Ramboll, an engineering-focused consultancy, says he expects to see more pilot projects pave the way for serious offshore hydrogen growth.

Karnik, a chartered mechanical engineer and member of the Institution of Mechanical Engineers (IMechE), says that, given how much water it takes to produce hydrogen, it makes sense to do it at sea. Old oil and gas pipelines can be repurposed and there are export opportunities for those who get it right. Karnik agrees that the costs can be pushed down if mass production takes off, and as renewable energy gets cheaper.

“The most important thing is to understand where offshore hydrogen solutions fit the best, and not to force them where they don’t make sense,” he explains. “Go for low hanging fruit. Tap into existing demand from heavy industry, chemicals, transport, shipping and aviation. Hydrogen helps industries that find it difficult to decarbonise.”

Mapping hydrogen storage capacities of UK offshore hydrocarbon fields and exploring potential synergies with offshore wind

As well as creating energy to turn into hydrogen, the North Sea’s hydrocarbon fields offer an opportunity for that hydrogen to be stored, as demonstrated by this map showing the location of offshore wind farms in relation to oil and gas fields.

data by Peecock et al.

It’s not all smooth sailing

Karnik, and other experts, say there are challenges that must be dealt with before offshore hydrogen hits its commercial breakthrough. Safety, for one, has always been a part of the hydrogen story. Going offshore presents new problems.

Building, fixing or maintaining structures on rough seas can be more expensive, Karnik explains. Pumping hydrogen through underwater pipes raises concerns about ecological impacts. There are unanswered questions about excess heat and oxygen created at hydrogen plants (it’s easier to find a use for those back on land). And there are concerns about whether electrolyser technology can develop fast enough to service a booming offshore hydrogen sector – with questions around how long the machines can last and how new designs will adapt to life at sea.      

One person anxiously waiting for answers is Professor Mohamed Pourkashanian, who heads the Energy Institute at the University of Sheffield. With 40 years of energy research under his belt, and an OBE for his contribution to the field, Pourkashanian jokes that his top three concerns are: price, price and price.

Cost of production, he says, remains a major hurdle. Others include clear government policies and electrolyser technology challenges.

“I’m looking forward to full lifecycle analyses,” says Pourkashanian. “Comparing technologies will tell us more about costs, practicality and the robustness of offshore hydrogen.”

Pourkashanian says he’s particularly interested to see how offshore compares to onshore production, and to local hydrogen facilities that could use small modular reactor (SMR) nuclear power instead of wind.  

“Every sector you can think of has the potential to use hydrogen. The sooner we get green hydrogen production, the better. It’s important to get it done, and produce it in large quantities. Otherwise, we won’t meet our 2030 targets.”

Licence to fill (the pipelines)

Matthews agrees, saying it’s important to put different technologies to the test and settle on those that deliver the best results. Failing to do that would be the equivalent of trying to mass-produce cars with hundreds of different engine types.

As Matthews sees it, the tallest hurdle is securing space to run demonstrator projects and stepping-stone facilities.

Offshore licences, he says, are crucial to building confidence and applying a stepped approach to learning and refining. In other words, they’ll give the industry the analysis and comparisons it needs. But competing in large licensing rounds can push projects beyond 2030, so Dolphyn is looking for partners and sites where existing licences can be modified to accommodate offshore hydrogen initiatives.

“One of the most rewarding things for us is to work on a solution that’s fit for our future. This industry is going to show something like a 40% compound annual growth rate,” says Matthews. “It’s innovative. It’s new. And my message is: don’t wait and watch. Get engaged, build up investment and plan to make a move.”

For engineers, endless puzzles to solve

While, like any new technology, offshore hydrogen has its sceptics, what everyone agrees on is that it offers exciting opportunities for engineers.

Matthews says that, as an adjacent industry – as opposed to an entirely new one – offshore hydrogen offers a chance for engineers to transition, relatively easily, from sectors such as oil and gas, construction or steel fabrication. Dolphyn Hydrogen has hundreds of companies in its supply chain and, Matthews adds, once construction begins at scale, thousands of jobs will be created.

Karnik says offshore hydrogen serves up endless puzzles – from solving pressure fluctuations to designing the most effective pipelines. Not to mention designing the kind of infrastructure that can withstand gale-force winds and pounding waves.

Hydrogen Europe, an association representing the industry, says engineers will play a key role in complex projects and can use their talents to bring down production costs.

“If we can crack the economics, it could be the single most important method of green hydrogen production in Europe, with its vast amounts of capacity around our western and north-western shores,” says Daniel Fraile, the association’s chief policy officer. “First movers will pave the way for widespread uptake of offshore hydrogen production.”

An invisible gas with plenty of colours:

There’s green hydrogen, blue hydrogen and even turquoise hydrogen. There’s grey, black and pink hydrogen. That’s a whole lot of colours for an invisible gas.

There are many ways to produce hydrogen. These colour labels help us understand how clean each method is. Ramboll, where Karnik works, has a handy guide to help you understand the hydrogen rainbow.