Ricardo invests in UK hydrogen research centre

Fuel cells are likely to prevail over internal combustion engines (ICEs) in the long-term quest for carbon-free marine propulsion, believes Andrea Trevisan, chief engineer at the UK-based engineering consultant, Ricardo.

It is exploring the potential of hydrogen and ammonia as zero-carbon fuels for both ICEs and fuel cells and Mr Trevisan told The Motorship that fuel cells’ dominance will be because they are more efficient than ICEs, making them cheaper to run. ICEs, meanwhile, will provide an “interim solution … to support hydrogen and ammonia adoption.”

He was speaking in early February, just a few days after Ricardo announced it was investing £2.5M (US$3.4M) in a hydrogen development and testing facility that will “form part of a global centre of excellence for hydrogen, defossilised fuels and electrified transport engineering,” a company statement said, with a focus on hydrogen, fuel cells and green alternative fuels. It is due to open early next year.

Ricardo is also hoping to establish a development facility for hydrogen-fuelled ICEs, but this will depend on securing government funding. A decision was expected as this issue of The Motorship went to press, but the company’s test operations director Richard Murphy was confident that funding would be granted. Once that has been confirmed, it can be in operation within four-six months, he said.

These are not Ricardo’s only recent ventures into hydrogen-fuelling: in mid-January, it formed a strategic collaboration with alkaline fuel cell specialist AFC Energy specifically to create hydrogen fuel cell products and services, initially focusing on marine, rail and stationary power applications.

Although fuel cells may be the eventual winner over ICEs, scaling them up for high-power applications will not be straightforward. With current technology, an individual fuel cell can be up to 60% efficient, which is about 10% more than for an ICE but that optimum figure is reached at around 25-35% load and reduces when cells are stacked together for higher outputs, Mr Trevisan said.

However, Ricardo has developed an advanced control system that can boost the efficiency of such a stack, restoring its efficiency to 50-60% and Mr Trevisan is confident that fuel cell technology is improving rapidly and that its efficiency will improve in the future.

Its planned development and testing facility is expected to support further development for Ricardo’s hydrogen transport technology using what the company described in a statement as a ‘systems-led’ approach. This, Mr Murphy explained, differed from a conventional approach in which various parts of a system, for example, an engine, transmission and other components, would be developed separately and then brought together.

Fuel cell systems, however, have more complex interdependencies, he said, so if that approach were used for their development, “you would then find a whole new set of learning” when they were combined. Because of this, developing systems as a whole “means a faster route to market and cheaper development time, which gives a competitive advantage,” he added.

Ricardo’s new centre will combine highly-detailed models with components to enable this ‘hardware-in-the-loop’ approach. “Swapping [between] the real and the virtual is one of the challenges for modern test facilities,” he added, but Mr Trevisan said this approach has a significant benefit: it reduces development time by 30% and a systems-led approach “makes sure that the customer’s needs are really met.”

Hydrogen fuelling challenges

However, hydrogen faces a significant challenge, particularly for marine use: storage volume. Even when compressed to 700 bar, it takes up nine times the space of the equivalent diesel fuel, Mr Trevisan said. This comes down to a multiple of five if it is held in liquid form and to three times the volume if the hydrogen is provided in the form of liquid ammonia. Other benefits of ammonia are that it can be transported relatively easily and it is already a familiar commodity, he noted.

But now, Ricardo is exploring a storage option that might bring the ratio down even more, by holding hydrogen as a metal hydride, which would absorb and then release hydrogen from its surface, requiring neither high pressurisation nor liquefaction.

In a UK government-funded joint project with London’s South Bank University, Ricardo is exploring the potential of this technology for fuelling buses, for which hydrogen’s cost, safety and on-board storage are significant obstacles to its commercial use, a Ricardo statement about the project said in December. It went on to suggest that metal hydrides would therefore provide a safer storage method with lower operational and maintenance costs.

Reflecting on its potential for marine use, this could be “quite a breakthrough,” Mr Trevisan commented.