A select committee of Senators, Department of Energy officials and commercial representatives recently gathered in Washington DC to examine emerging offshore and marine energy technologies in the United States, including alternative fuels for maritime shipping.
Chaired by the Senator from Alaska, Lisa Murkowski, the committee comprised the Senator from West Virginia, Joe Manchin, Assistant Secretary for the Office of Energy Efficiency and Renewable Energy, Daniel R. Simmons, Senior Counsel, Clean Air Task Force, Jonathan Lewis, as well as other representatives from the public and private sectors.
Addressing Simmons and Lewis, Senator Manchin asked whether the US was on track to meet the industry needs of commercially viable, low-emission vessels in 10 years.
‘I don’t know is the safe answer,’ said Simmons. ‘Our bioenergy technology office has a new focus on heavier fuels such as biofuel for jet but also biofuel for heavy applications for marine. If it is ammonia, I don’t think we would get there. I think we can get there with a biofuel that is a heavy biofuel… if it’s a pure drop-in fuel, within 10 years.’
Manchin then asked Simmons to identify low-carbon technologies that required the most investment in order for the sector to meet the low-emission goals.
‘Definitely on these heavy biofuels it is very important but also [investment] in ammonia is a critical technology because it’s a hydrogen carrier.’
Manchin then put the same question to Lewis.
‘We think that biofuels present some sustainability and scalability problems, and they’re also going to face serious competition from the aviation sector,’ he said.
He continued: ‘We think ammonia is going to play a critical role in decarbonising the sector. There’s work being done on a handful of different fronts, at universities around the world - including the University of Minnesota and Texas Tech - on ammonia-fuelled internal combustion engines - and there’s work going on in the marine space.’
Lewis then highlighted the ammonia-compatible dual-fuel engines currently being developed by MAN Energy Solutions.
‘The company [MAN Energy Solutions] has said that it can deliver ammonia-compatible engines to the market by 2024. Other engine developers, such as Wärtsilä and Samsung Heavy Industries, are also moving in this direction and American engine companies are also well-positioned to advance the development and deployment of these engines. Caterpillar, for example, filed patent application for an ammonia-fuelled engine in 2008, so they should be ready to move forward as well.’
Manchin noted that Europe had ‘led the way’ in manufacturing and building offshore wind projects.
Manchin said: ‘Given the size of those turbines it seems to me that it would not only make sense to build them here at home for US projects but it would also present an opportunity to reinvest in our port, shipbuilding and domestic workforces. The same should be same for marine energy technologies and low-carbon shipping fuels…’
Manchin noted that industries in his home state of West Virginia could also help boost some of these efforts by drawing on its natural gas resources to make hydrogen or ammonia for shipping.
Next to speak was the junior Senator from Washington, Maria Cantwell, who highlighted Washington State Ferries’ decision to electrify its fleet with the replacement of 13 diesel ferries with hybrid electric vessels and the conversion of six other plug-in hybrids.
‘I have visited some of our shipbuilding facilities in the state who are building these electric ferries for other parts of the United States – very easy onload/offload passenger ships. Where should we be going and further [incentivising] that?’ Cantwell asked.
‘That’s a tough question for me when it comes to further incentivising it,’ said Simmons. ‘There is definitely research that needs to be done in terms of how do we charge. The ferries use an amazing amount of energy.’
Simmons told the select committee that he had had the opportunity to visit the engine room of one of Washington State Ferries’ vessels.
‘It is a huge vessel. When that pulls in and is connected to the dock, it is a lot of electricity that is flowing very quickly. That is a serious challenge for batteries to be able to take in all that electricity – it degrades the battery. There are definitely R&D challenges to further that technology, but it is rather exciting,’ said Simmons.
Senator for Nevada, Catherine Cortez Mastro, then asked Lewis to expand on the economic opportunities that hydrogen and ammonia fuels provide for non-marine states in the US such as hers that are focussing on a robust energy portfolio.
Lewis said: ‘We think there are significant opportunities for inland states because producing enough zero-carbon fuels for the marine sector and other sectors is going to be sort of “all hands on deck” requirement.
‘The key attribute of hydrogen and ammonia fuels is that they can be produced and used in so many different ways. We think it’s likely that scale-up in zero-emission hydrogen production is going to be achieved through the use of expanded renewable energy power, nuclear power and gas reforming with carbon capture.’
Lewis continued: ‘Some of the jobs associated with this scale-up involve new technologies and new skill sets while others are going to be pretty similar to jobs that already exist in the petrochemical industry. Ultimately, we’re going to need to produce liquidating gaseous fuels for using technologies that are similar in many ways to conventional refineries but do a better job managing carbon flows. Those are large installations that require people to build and to run them.
He added: ‘We’re also going to significantly expand our distribution from places like Nevada to ports and other demand centres around the country. That means building a lot of pipelines, storage tanks, fuelling terminals and lots of jobs building, servicing and operating that equipment.’
Junior Senator from Maine, Angus King, then asked the committee to discuss the advantages and disadvantages of ammonia and hydrogen in terms of generating, storing and deploying the fuels.
Lewis said: ‘Whether we’re making hydrogen neat for use in fuel cells or ammonia use in internal combustion engines and other systems, we start with hydrogen and we want to make hydrogen without carbon. But the difference at the point – whether or not you keep it as hydrogen or turn it into ammonia - depends on your intended application.’
He continued: ‘Ferries…are a potential terrific user of hydrogen-based fuel cells because you are working in a near-shore application, you’re not trying to cross the ocean, you can refuel more frequently.
‘If you’re trying to cross an ocean, you need something that is a little more energy dense, that’s easier to store, and ammonia is much easier to store, especially in large volumes than hydrogen.’
King then asked Lewis to compare the energy densities of ammonia and diesel fuel.
‘Ammonia has about half the energy density of diesel fuel,’ Lewis said.
‘Is it used and stored in an internal combustion situation in a liquid form?’ King asked.
‘Yes,’ Lewis replied.
‘So, you need larger tanks,’ King asked?
‘You need a larger tank that is slightly refrigerated,’ explained Lewis. ‘There are engineering firms and shipbuilding firms around the world that are working on mitigating that challenge and they think they see paths forward.’
‘And can current diesel engines be retrofitted to use ammonia?’ asked King.
‘We think so,’ said Lewis. ‘We’re very eager to see some of the first commercial applications of that. There are several companies around the world…that are working on that. These are large engines and significant investments and it would be great if we could take the existing fleet and make it ammonia-compatible.’
‘So, the ideal is hydrogen and ammonia generated by renewable power offshore [where] you could generate during periods of light demand?’ asked King.
‘That would certainly work,’ said Lewis. ‘We think there are a lot of different ways to make zero-carbon hydrogen. Whether it’s from renewables, whether it’s from nuclear, whether it’s from steam methane reforming with [CO2 capture and storage]; all of these technologies would need [Department of Energy] investment.’
