Compressed hydrogen has received little airtime in the future fuels global frenzy, especially in Australia. Determined to remain a global energy provider by switching exports from brown to green, Australia is infatuated with the question of how to get its hydrogen to the jaws of a hungry global market.
Viewed from this angle, liquefied hydrogen–which involves cooling the loose hydrogen gas until it tenses up and becomes a liquid–looks far more attractive, as you can fit five times more of the shrunken molecule in a vessel. Ammonia, which is composed of one nitrogen atom bonded to three hydrogen atoms, is sexier yet–boasting a density of seven times hydrogen gas. “It all comes down to how much you can make and get to your market. That’s what I think is front-of-mind,” Scott Hamilton, senior advisor and consultant at the Smart Energy Council, told pv magazine Australia.
While attention has fixated on hydrogen’s thicker cousins, Western Australia company Global Energy Ventures (GEV) viewed the issue of transport from its own unique lens. Having spent four years designing a ship to transport compressed natural gas, the company’s dozen employees figured: ‘why not apply the same principles for hydrogen?'
Delightful findings
GEV released its design for a vessel which would not only transport, but also run on, compressed hydrogen in November of 2020. It then went a step further, commissioning GHD Advisory to undertake a scoping study weighing up compressed hydrogen against ammonia and liquid hydrogen as an end-to-end zero-emissions supply chain. To industry surprise, compressed hydrogen emerged far from the ‘Plain Jane' it had initially seemed.
While the company’s clearest offering is its ship design, it is urging the industry to take a broader perspective when it comes to compressed hydrogen. “This is about the end-to-end supply chain, not just the ship,” said Global Energy Ventures executive director Martin Carolan.
The scoping study found compressed hydrogen to be “extremely competitive” when shipped at less than 2,000 nautical miles. Compressed hydrogen remained competitive compared to ammonia and liquefied hydrogen when transported at distances of up to 4,500 nautical miles–roughly the distance between the northern half of Australia and Southeast Asia.
“That was a revelation for the industry because no one had ever thought that compression, from a shipping perspective, would be in the mix for that distance,” Carolan told pv magazine Australia.
“We’re not trying to dismiss the alternatives. Overall, in the next 10 years I think everyone can get there … the point is that the simplicity and efficiency of our [supply chain] should be considered.”
The infrastructural case for compressed hydrogen
The crux of the case rests on speed. Compressed hydrogen’s key advantage is that the gas lines and infrastructure used to load and unload compressed natural gas can be repurposed to carry hydrogen.
“That’s why we talk about minimal technical barriers,” said Carolan. “We just need to [get approvals for] the ship. The other components in our supply chain will be there and ready to go.”
Of course, the re-purposing isn’t quite that easy. Traditional gas lines can only carry a blended gas that is up to 15% hydrogen. And for the SEC’s Scott Hamilton, the rosy picture comes with a caveat.
“There’s quite a lot of debate about whether we should be encouraging the injection of renewable hydrogen into existing gas networks,” he told pv magazine Australia. “When we look at the idea of injecting the gas [hydrogen] into existing pipelines, we need to be very cognizant… to make sure we have excellent leak protection and repair systems and processes in place to make sure that we’re not inadvertently causing a major problem.”
Be that as it may, Hamilton is pro re-purposing, at least in the meantime. “I’m encouraging doing that as a short term measure. In the longer term, we’re going to need purpose-built infrastructure and pipelines.”
This infrastructure leg-up is vital. Carolan estimates it would be possible to get a compressed hydrogen supply chain to be up and running in just three to five years. On the other hand, some estimates place commercial liquid hydrogen and ammonia supply chains a decade away.
The reason for that is that we simply don’t yet have all the technology needed to make liquid hydrogen commercially viable, or the ammonia supply chain with zero emissions. “There’s still technical advances needed there,” Carolan said.
Ammonia and liquid hydrogen’s embedded issues
Liquid hydrogen needs to be stored at -253 degrees Celsius to remain liquid–no easy feat. Likewise, because ammonia throws a nitrogen atom into its hydrogen mix, customers wanting pure hydrogen will need to ‘crack’ their ammonia at the end of its global journey, essentially snapping the molecule apart.
Transporting a liquid at -253 degrees Celsius across the world and cracking ammonia molecules are both, at this point in time, not technically possible at scale. Neither Carolan nor Hamilton believes the problems are unsolvable, the question is just what time and cost.
Likewise, while the density of ammonia and liquid hydrogen make them more attractive for transport, the characteristic comes at a price: embedded energy.
Unsurprisingly, it takes a lot of energy to shrink molecules and to crack them apart. If the aim of the game is a completely zero-emissions supply chain, Carolan argues ammonia and liquid hydrogen are both on the back foot.
Scott Hamilton is less worried by these elements. He thinks the technical hurdles to commercializing green hydrogen supply chains can, and will, happen “quicker than expected.”
Popular content
“Similar to how we’ve underestimated how quickly the cost of solar, wind and now batteries would drop, I think we’ll now see the cost of electrolysis, liquefaction also drop,” he said. “But that doesn’t mean there’s not going to be timing and sequencing issues, and it doesn’t mean there’s not going to be a role for different forms and types of hydrogen.”
A situation of ‘both, and’ not ‘either, or’
For Hamilton, green hydrogen’s formational journey is less a story of dogged competition than one of multiple pathways.
“We have to let the 1,000 green hydrogen roses bloom to see what is going to make the best. I think everyone is going to have a view on this, and I really encourage that. What we’ve really got to do is get these projects happening and get this occurring so we can find out.”
With green hydrogen markets expected to grow tenfold in the coming decades, both Hamilton and Carolan believe there will likely be room for the market to accommodate multiple forms.
“I think there’s going to be various markets and demands for renewable hydrogen in different forms,” Hamilton said. “It’s likely to be an ‘and’ not an ‘or.’”
Potential for use on offshore wind platforms
Carolan says he’s been in discussions with a number of European companies which are exploring the possibility of producing green hydrogen on offshore wind platforms when there is extra capacity available. While not far from shore, the green hydrogen will still need to find its way to land.
“There will be instances where a pipeline will work, and instances where a pipeline will not work. So what’s the alternative? We think that compression is ideally suited to that part of the world, with much shorter distances.”
Carolan proposes that it would be quicker and easier for these companies to compress hydrogen and let GEV’s ships ferry it a few hours to shore, instead of undergoing the more burdensome processes of turning the hydrogen into liquid or ammonia, only to shift it back into gas a few hours later.
“It just doesn’t make sense to us that you would run through such extensive chemical capital and energy-inefficient processes just to move the energy source from A to B.”
Yet the supply chain isn’t limited to short distances, Carolan insists. Buoyed by the results of the scoping study, Carolan has his eyes firmly on Southeast Asian markets for GEV’s green hydrogen.
“It’s really not clear how big the market is, but we know that, within a regional context, if it’s, today, a 10 million ton market, then it’s going to grow tenfold.” Global Energy Ventures is keen to get a piece of the pie and is confident it will be able to deliver the green hydrogen countries like Japan, South Korea and Singapore want more quickly and easily, than the projects which are only looking at liquid and ammonia supply chains will. “We’re a three to five-year scenario for having our ship ready.”
Forget exports, decarbonizing shipping alone is a windfall
While the Smart Energy Council is as excited as anyone about the potential for Australia’s green hydrogen export market, Hamilton noted decarbonizing global shipping alone would be a jackpot for well-positioned companies.
“That’s a huge opportunity for Australia and for companies like [Global Energy Ventures] to be involved in.” As he pointed out, experts expect US$1.9 trillion worth of investment will be needed to decarbonize shipping by 2050.
“I’m happy to be collaborating with these guys, I think they’re really doing some very exciting work in terms of the development of these new technologies,” Hamilton added.
In search of partnerships
This type of collaboration–or, more specifically, partnership–is precisely what Global Energy Ventures needs to proceed to the next stages of its proposal.
After it revealed the designs for its compressed hydrogen vessel less than six months ago, Global Energy Ventures was approached by fuel-cell manufacturer Ballard Power Systems. “It really solidified for us that we were on the right track,” Carolan said. The two companies are now formally working together to get the ship’s propulsion to be as efficient as possible.
The Western Australia company is yet to sign any agreements with partners in the two other areas it seeks them–namely in the form of Australian green hydrogen production projects and end users.
It is looking to make a deal with a production project located anywhere between the mid-west of Western Australia and Gladstone, in Queensland–including all of the Northern Territory–sometime this year.
The ultimate goal there is to partner with a project that would create at least 30,000 tons of green hydrogen annually, which is what the company believes would be the scale required to warrant the construction of three demonstration ships which it would use to prove–then hopefully commercialize–its compressed hydrogen supply chain.
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.
There is a fundamentally new Australian idea for making green ammonia using plasma reactors, roughly how nature does it with lightning: https://www.greencarcongress.com/2021/01/20210122-nh3.html Since the legacy Haber-Bosch process is energy-intensive, we could see a revolution here, or at least a real competitor for molecular hydrogen.
Very imformative, well written article that thoroughly covers the subject. From a lay person who is interested in the subject, thank you, Ms. Peacock.
PS: the company’s pictured ammonia supply chain is absurd. Nobody is going to convert hydrogen to ammonia, ship that, and then convert back to hydrogen (say for DRI) at the destination. Ammonia has a huge current market in fertiliser, and with moderate effort can be used directly as an energy-dense fuel in fuel cells, diesel engines, heat pumps and gas turbines. I assume you would not try to use ammonia for cooking, but that market is going electric anyway.