Will Green Hydrogen Fulfill High Hopes for Trucking and Shipping Emissions?

by Angeli Mehta (Reuters Events) While there's debate over whether the technology stacks up against batteries for long-distance trucking, the case in maritime usage seems more clear-cut. Angeli Mehta reports

“Everyone loves hydrogen,” observed Fatih Birol, executive director of the International Energy Agency (IAE), recently during a recent conference called to discuss an element that has long been used in industry but is now seen as essential in the race to net-zero.

From Namibia to Canada, Chile to the EU, policymakers are looking at hydrogen as never before.

The IEA believes hydrogen has an important role to play in decarbonising heavy transport, shipping and aviation, sectors that are difficult to electrify, but to get anywhere, demand will have to grow seven-fold from today, and that will require policy and infrastructure to kickstart the industry.

Julia King, a cross-bench peer and engineer who chairs the Carbon Trust, told the same conference that hydrogen would inevitably be more expensive than methane or electricity. “It's only when we have the driver of the commitments governments are making to net-zero, and the requirement to decarbonise processes that we can't electrify, that hydrogen becomes really essential in bulk for energy purposes.”

An entire industry must be created because hydrogen doesn’t exist on its own in nature. It has to be made either from fossil fuels, which creates carbon dioxide (so-called grey hydrogen), or by using renewable energy to electrolyse water, splitting it into hydrogen and oxygen (green hydrogen).

In Europe, sectors such as chemicals already use some 10m tonnes of hydrogen a year, with about 4% being produced by electrolysers.

The use of carbon capture and storage to remove emissions from grey hydrogen, so called blue hydrogen, is promoted as an interim solution until green hydrogen is cost-competitive, but the world's first at scale CCS project on hydrogen, Equinor's venture in the north-east of England, isn't scheduled to begin operating until 2026.

Partnerships are being formed across the world to make hydrogen in industrial clusters that will create supply and demand in close proximity; hubs in the UK and the port of Rotterdam are examples. ... Chile, Morocco and South Africa have huge untapped renewable energy resources that could make them players in a hydrogen economy. Already Germany is backing a plant in Morocco to produce green hydrogen. The Orkney Islands, off Scotland’s northern coast, have been producing hydrogen from excess renewable energy and using it to power vans and a prototype ferry.

Taking into account losses in conversion all along the chain, from electrolyser to wheel, suggests three times more electricity is required to move one of its(Scania's) trucks using hydrogen compared to a battery.

“So we think the use of hydrogen in real life is going to be more appreciated if it's converted into thermal energy [to heat buildings, for example], rather than being a fuel cell and on the wheel on a truck.”

Another consortium, HyShip, aims to build a series of prototype vessels running on liquid green hydrogen, beginning with a cargo ferry powered by a combination of battery electric and hydrogen fuel cells. The 14 partners want to have the vessel operating by 2024, taking both cargo and hydrogen fuel to ports and bunkers along the Norwegian coast.

But it will not come cheap. More than $1.4tn of capital investment will be needed if the shipping industry is to decarbonise by 2050. This is based on ammonia (made from hydrogen) being the dominant low-carbon fuel. Ammonia is already moved in huge quantities around the world and, while toxic and corrosive, is easier than hydrogen to ship and distribute.

A joint venture in Saudi Arabia plans to make 1.5m tons of green ammonia a year by 2025 – to be shipped and cracked back into hydrogen for buses and trucks. Hundreds of such plants would be needed to decarbonise shipping. Ammonia has the advantage that it can be burned in an internal combustion engine, although that produces nitrogen oxides, potent greenhouse gases. Methods to eliminate these emissions are being worked on.

Ammonia and hydrogen are also being explored as aviation fuels (see Sustainable aviation fuels get powerful boost from pandemic). In the UK, Reaction Engines and the Science and Technology Facilities Council (STFC) are working to demonstrate how ammonia could be used for short-haul flights (of up to 2,000km). The system wouldn’t require wholesale aircraft or engine redesign, and more of the energy produced by burning ammonia is utilised compared to kerosene. If the concept is proven, the research team anticipates ammonia-based propulsion systems could be ready to enter service by 2030. READ MORE