MIT Looks Ahead to Hydrogen’s Aviation Future

This article is a part of our unique IEEE Journal Watch collection in partnership with IEEE Xplore.

As funding in hydrogen-powered flight expands, airports and air carriers immediately are realizing that it’s not sufficient to retrofit or design new planes for hydrogen energy. So whereas researchers and firms giant and small put money into the zero-carbon way forward for the sphere, others are starting to review what provides and infrastructure on the bottom would even be wanted to make hydrogen aviation a actuality.

“Hydrogen may be a good thing, but you gotta look at it from the full system level, right?,” asks Professor R. John Hansman, an aeronautics and astronautics professor at MIT and director of the college’s International Center for Air Transportation. “Because it won’t work unless you have all the pieces to make it work as an operating system. There’s a lot of technology that would have to be developed.”

Chicago O’Hare would demand the equal of 719 tonnes of liquid hydrogen per day.

The first problem is hydrogen manufacturing. A paper co-authored by Hansman and a number of other MIT college students—and introduced this summer time on the IEEE International Conference on Future Energy Solutions on the University of Vaasa in Finland— thought-about the case of supplying sufficient liquid hydrogen for 100 airports worldwide, every with long-haul flights. (Only a couple of hundred airports assist flights that journey greater than 4,800 kilometers globally.)

The concept, Hansman says, was to deal with a smaller set of airports and, theoretically, restrict the potential new infrastructure that is perhaps required by hydrogen-powered flight. But simply supporting liquid hydrogen-powered long-haul flights at these airports would quantity to greater than 30 p.c of present international nuclear power manufacturing per day, in line with the researchers’ calculations. Chicago O’Hare, for example, would demand the equal of 719 tonnes of liquid hydrogen per day.

And the hydrogen must both be produced by clear or nuclear power to supply actual local weather advantages, the paper famous.

The analysis hinted at different logistical challenges, too, together with transporting and storing hydrogen in an environment friendly approach. For instance, in line with the researchers, sustaining two days’ value of liquid hydrogen for long-haul flights at Chicago O’Hare would require 5 storage tanks equal to the dimensions of the liquid hydrogen storage tank on the NASA Kennedy Space Center—the biggest on the planet as of 2021.

It’s potential that some airports might produce hydrogen onsite, the researchers added, however others won’t have the room.

Liquid hydrogen might require a brand new loading course of, too. Fueling hydrogen in a approach that’s much like customary jet gasoline might require cryogenic equipment, because the liquid hydrogen would must be transported at extraordinarily low temperatures, in line with Arnaud Namer, the chief working officer at Universal Hydrogen, a hydrogen-focused transportation startup. This equipment might be costly and heavy, he famous, and transporting hydrogen on this approach might additionally create the danger of loss, creating less-than-ideal security and local weather impacts.

One firm is creating modular hydrogen capsules, which might every carry round 200 kilograms of liquid hydrogen—the “Nespresso model.”

In the same vein, a 2022 paper from researchers in Germany analyzing hydrogen refueling logistics thought-about the potential advantages of a number of completely different refueling methods, resembling vans and pipelines and hydrants. The major methodology anticipated by Julian Hölzen, one of many authors of that challenge, are vans.

“These are nearly available [and] commercialized today, easily scalable, come with relatively low capital costs, and at airports with no traffic constraints they are a perfect first step for LH2 aircraft refueling,” Hölzen stated in an e-mail. “The pipeline-and-hydrant option is the best option from an engineering perspective. But might not offer the economics for medium-sized airports and comes with less flexibility.”

Refueling raises one other open query. Hydrogen, Hansman provides, is extraordinarily flammable, which suggests gasoline traces would must be cleared. While NASA usually depends on helium, a brand new method to purge gasoline traces could also be wanted to work for a business aviation setting.

“Let’s just say you want to refuel the airplane in an hour or two, right? Well, so it turns out, it’s tricky to do that,” he stated.

Right now, there are different concepts, however they could not work for all types of flights. Universal Hydrogen is creating modular hydrogen capsules, which might every carry round 200 kilograms of liquid hydrogen. While Hansman notes this strategy won’t be workable for long-haul flights, Namer says this know-how might be used on any sized plane.

“That’s similar to the Nespresso model. You actually use capsules, where you fill the hydrogen at the production site with these capsules,” explains Namer. “In that sense, there’s no infrastructure development to be done at the airports or on the ground handling because you’re moving your fuel like you’re moving cargo with the same kind of equipment.”