The world is undergoing an energy transition to reduce CO2 emissions and mitigate climate change. The COVID-19 pandemic and the Russia-Ukraine war have further increased the interest of Europe and Western countries to invest in the hydrogen economy as an alternative to fossil fuels. Hydrogen can significantly reduce geopolitical risks if the diversity of future hydrogen energy suppliers is increased.
Hydrogen is a particularly challenging product to transport safely. One option is to liquefy hydrogen, which requires cooling to 20 Kelvin (-253 °C). This is an expensive process and requires around 30% of the energy stored within the hydrogen.
A pioneering approach developed by IIASA researchers and colleagues proposes solid air (nitrogen or oxygen) as a medium for recycling cooling energy across the hydrogen liquefaction supply chain. At standard temperature and pressure, air is a gas, but under certain conditions, it can become a liquid or solid. Solid Air Hydrogen Liquefaction (SAHL) consists of storing the cooling energy from the regasification of hydrogen, by solidifying air, and transporting the solid air back to where the hydrogen was liquefied. The solid air is then used to reduce the energy consumption for liquefying hydrogen. The process is divided into four main steps: hydrogen regasification, solid air transportation, hydrogen liquefaction, and liquid hydrogen transportation.
[...] In their paper, the authors also address the ongoing debate in industry and academia to find the best alternative to transport hydrogen by sea:
"Compared to ammonia or methanol, liquefied hydrogen is the best option for several reasons. Transporting hydrogen with ammonia and other molecules would require around 30% of the energy transported to extract the hydrogen. The hydrogen is liquefied where electricity is cheap. Also, SAHL can lower energy consumption for hydrogen liquefaction by 25 to 50%," Hunt concludes.
Journal Reference:
Hunt, J., Montanari, P., Hummes D., et al. (2023). Solid air hydrogen liquefaction, the missing link of the hydrogen economy. International Journal of Hydrogen Energy DOI: https://doi.org/10.1016/j.ijhydene.2023.03.405
(Score: 2) by sjames on Tuesday May 23 2023, @04:32PM (2 children)
We somehow come up with hydrogen that totally isn't being derived from fossil sources, use a bunch of energy to liquify it, burn some of it delivering it elsewhere, re-gassify it and freeze some air. Burn more hydrogen taking most of that air-ice back to the hydrogen plant and use it to help liquifying the hydrogen.
With all of that, the losses from electrical transmission are starting to look attractive.
(Score: 0) by Anonymous Coward on Wednesday May 24 2023, @03:10AM (1 child)
Not enough progress on hydrocarbon or alcohol fuel cells and "prefilters/preprocessors"?
(Score: 2) by sjames on Wednesday May 24 2023, @10:31PM
That's something I'm wondering. Unlike just shipping the hydrogen, synthesized methane is comparatively easy to transport and we have existing infrastructure for it. Combine it into synthetic propane and it becomes fairly simple and inexpensive to convert an existing ICE to use it.
If it's synthesized with CO2 from the air, it will be just as carbon neutral as hydrogen itself.