This Week in Engineering explores the latest in Engineering from academia, government and industry.
Episode Summary:
NASA has launched the DART mission to intercept an asteroid and deflect its path. The purpose is to demonstrate how satellites can be used as kinetic energy impactors to alter the course of asteroids and comets that may be on a collision path with Earth. The European Space Agency is collaborating, and the Italian national space agency has supplied a ride along cubesat to photograph the impact. The mission also contains an important development, a test version of an Aerojet Rocketdyne built xenon ion thruster that may form the basis for a new class of deep space satellite propulsion for missions with durations of a decade or more.
Fuel cell technology has been around for decades but has been overshadowed by battery storage and electric motors for transportation purposes. But the field is far from obsolete, and a new way to power them they remove many of the obstacles created using pure hydrogen. New York-based Plug Power has opened a Rochester giga factory to produce hydrogen from electrolysis of water in support of fuel-cell technology and is supplying systems to multinational fertilizer consortium Fertiglobe for an Egyptian plant that will pioneer large-scale green ammonia production. Ammonia is a promising carrier for hydrogen and can itself be a green fuel for combustion engines and in fuel cells.
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Transcript of this week’s show:
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Segment 1: The prospect of an asteroid crashing into the Earth has been a staple of science fiction for decades, and a leading theory about mass extinction events millions of years ago. But could it happen in our lifetime? And if we can see it coming, what can we do about it? Well, NASA has just launched an experimental mission called DART, or Double Asteroid Redirection Test, to determine if a satellite can be used to deflect an asteroid or comet from an Earth collision path.
Launched November 24 on a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California, the test spacecraft will intercept an asteroid that is not a threat to Earth, with the goal of changing its trajectory enough to be measured with ground-based telescopes. The test, built and managed by the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, is ambitious. The DART spacecraft will autonomously navigate to the target asteroid called Dimorphos and collide with it with enough force to change its trajectory noticeably and to create a debris cloud. Dimorphos is a moonlet of a larger asteroid, Didymos, which is approximately 2500 feet in diameter.
The European Space Agency will attempt to detect the collision displacement with a ground based telescope approximately four years after the impact. To photograph the actual collision, the spacecraft will eject LICIACube, a CubeSat provided by the Italian Space Agency (ASI).
Another forward-looking technology will be tested on the mission: ion thrusters. Powered by a pair of 20 foot long rollout solar arrays, the Aerojet Rocketdyne built Evolutionary Xenon Thruster – Commercial (NEXT-C), prototype is expected to be a new class of propulsion systems for deep space exploration, offering low levels of thrust, but for sustained periods of time, delivering much higher spacecraft velocities than conventional chemical rockets in long-duration missions. If the DART mission succeeds, they could form the basis for the first planetary defense system against a threat from space.
Segment 2: Fuel cells were once touted as the CO2 free alternate energy source of the future, at least before Tesla came along, but the technology has never gone away. In fact, it has advanced for many applications, and it still shows promise for many power needs. Latham, New York based Plug Power Inc. a green hydrogen development company, announced several interesting developments in this space.
The company has opened a green hydrogen and fuel cell giga factory in Rochester New York, and has completed the acquisition of Applied Cryo Technologies, a tech and service provider for storage and distribution of cryogenic gases, including liquid hydrogen. The company previously inked a deal with French hydrogen startup Lhyfe to codevelop green hydrogen plants in Europe.
There’s a lot going on a Plug Power, but perhaps the most interesting development is a deal with multinational Consortium Fertiglobe to provide technology for a 100 MW electrolyzer to produce green hydrogen gas at a facility in Ain Sokhna, Egypt. The hydrogen will be used as a feedstock for up to 90,000 tons of annual production of green ammonia for the Egypt Basic Industries Corporation. EBIC is a maker of fertilizer, and ammonia is an important global commodity in that sector, but the system has interesting implications for other carbon neutral purposes.
Green ammonia can be used as a carrier fuel to store and transport hydrogen and can itself be used as a fuel for internal combustion engines and for fuel cells. Ammonia is attractive as a fuel. With energy density of 12.7 MJ per litre, it is significantly more energy dense than even liquid hydrogen at 8.5 MJ per litre, and ammonia can be stored at commercial refrigeration temperatures, -33C, rather than the deeply cryogenic -253C required for liquid hydrogen. Ammonia is also less flammable than hydrogen, although it is toxic.
Can ammonia play a part in future green energy systems? It has one other advantage compared to other renewables in development: the world already manufactures 180 million metric tons of it every year for industrial use and for fertilizer, so the infrastructure is already in place.
