(SIM) AMMONIA POWERED FLIGHT

One engine will run on ammonia and two on conventional jet fuel during test flights, scheduled to begin next year. Photo: Aviation H2

While the world may be focused on pure hydrogen as the most significant promise for clean-burning aviation fuel, Australian company Aviation H2 is looking to speed things up by utilizing the compound of nitrogen and hydrogen, commonly known as ammonia or NH3.

"Green" ammonia is often mentioned when it comes to decarbonizing the transport sector, but mostly in reference to trucking or long-haul shipping. 

Meanwhile, brothers Christof and Helmut Mayer, directors of Aviation H2, are planning to have a Falcon 50 business jet in the air and flying (partially) on ammonia by mid-2023 - in just a little over a year's time. They will then seek to certify and commercialize their engine retrofit product via a planned public listing towards the end of the year.

Could using ammonia instead of pure hydrogen be a way of solving the onboard storage conundrum that the particularities of the gas entail?

The Sydney-based brothers believe so and are focusing on converting existing airframes and engines to be powered by ammonia. Christof Mayer told New Atlas in an interview over the weekend,

"Hydrogen gas is very light for the energy it holds, and liquid hydrogen is even lighter. But the tanks are big and heavy. We certainly don't discount liquid hydrogen or any other form of hydrogen as an option. We're not shutting those down. We're just going with ammonia for now. It's the simplest conversion, and that intrinsically will make it the most reliable, and that in itself makes it intrinsically the safest."

The company is focusing on ammonia as a combustion fuel, which means regular jet engines can be modified to run on the colorless but somewhat distinctly pungent gas. For operators currently investing in new aircraft with lifespans in the decades, this may be a more welcome approach than retrofitting their new acquisitions with hydrogen fuel cell powertrains. Mayer added,

"We need to modify the fuel storage system into something that's basically similar to an LPG tank. So it's the fuel storage, the engine control, and the engine, those are the big-ticket items that we need to develop. But we're not really changing the design of the engine much at all physically."

Aviation H2 has partnered with FalconAir, a specialist aircraft charter operator serving Australia and the Asia-Pacific region. The collaboration will see FalconAir help acquire turbofan engines for ground-based testing. The company will also provide the aircraft itself, a nine-seater Dassault Falcon 50. Simple Flying - link - Linnea Ahlgren - link - more like this (HN3) - link - more like this (Australia) - link

(MAR) AMMONIA FUELLED CAR CARRIER GETS AIP

Ammonia: It's toxic, it's corrosive but it doesn't emit CO2 when burned and K-Line has plans to fuel this car carrier with it.

ClassNK has issued an Approval in Principle (AiP) to Kawasaki Kisen Kaisha, Ltd. (K-Line) and shipbuilder Shin Kurushima Dockyard Co. Ltd. for their jointly-developed design for an ammonia-fuelled car carrier.

Since it does not emit CO2 when burned, ammonia is high on the list of future fuels favoured for shipping decarbonization. However, major issues include that it is both toxic and corrosive. 

While international standards for using ammonia as a ship fuel have yet to be developed, in August ClassNK published its “Guidelines for Ships Using Alternative Fuels.” These address how to minimize the risks presented by ammonia to ships, , crew, and environment by stipulating requirements for installation, controls, and safety devices.

ClassNK, along with K-Line and Shin Kurushima Dockyard, assessed and investigated the car carrier design’s safety measures against the potential leakage risks of ammonia. The knowledge gained from this investigation was incorporated into the design, which was then reviewed in line with the “Guidelines for Ships Using Alternatve Fuels” and granted the AiP. MarineLog - link - Nick Blenkey - link - more like this - link

(PHY) AMMONIA - THE CARBON FUEL ALTERNATIVE

A research team at the University of Wisconsin-Madison has identified a new way to convert ammonia to nitrogen gas through a process that could be a step toward ammonia replacing carbon-based fuels.

The discovery of this technique, which uses a metal catalyst and releases—rather than requires—energy, was reported Nov. 8 in Nature Chemistry and has received a provisional patent from the Wisconsin Alumni Research Foundation.

"The world currently runs on a carbon fuel economy," explains Christian Wallen, an author of the paper and a former postdoctoral researcher in the lab of UW-Madison chemist John Berry. "It's not a great economy because we burn hydrocarbons, which release carbon dioxide into the atmosphere. We don't have a way to close the loop for a true carbon cycle, where we could transform carbon dioxide back into a useful fuel."

To move toward the United Nations' goal for the world to become carbon-neutral by 2050, scientists must consider environmentally responsible ways to create energy from elements other than carbon, and the UW-Madison team is proposing a nitrogen energy economy based on interconversions of nitrogen and ammonia.

The scientists were excited to find that the addition of ammonia to a metal catalyst containing the platinum-like element ruthenium spontaneously produced nitrogen, which means that no added energy was required. Instead, this process can be harnessed to produce electricity, with protons and nitrogen gas as byproducts. In addition, the metal complex can be recycled through exposure to oxygen and used repeatedly, all a much cleaner process than using carbon-based fuels.

"We figured out that, not only are we making nitrogen, we are making it under conditions that are completely unprecedented," says Berry, who is the Lester McNall Professor of Chemistry and focuses his research efforts on transition metal chemistry. "To be able to complete the ammonia-to-nitrogen reaction under ambient conditions—and get energy—is a pretty big deal."

Ammonia has been burned as a fuel source for many years. During World War II, it was used in automobiles, and scientists today are considering ways to burn it in engines as a replacement for gasoline, particularly in the maritime industry. However, burning ammonia releases toxic nitrogen oxide gases. Phys.Org - link - Tatum Lyles Flick - link - more like this - link