Revolutionizing the skies: Hydrogen tanks paving the way for zero-emission flights

Research Background

In an era where climate change looms large, the aviation industry—responsible for 3%–4% of global CO2 emissions and growing—faces immense pressure to go green without grounding our connected world. Aviation powers trillions in economic activity and millions of jobs, yet its reliance on fossil fuels spews not just CO2 but also NOx, particulates, and other pollutants that harm air quality and accelerate global warming. Enter hydrogen: a boundless, clean-burning fuel that could slash in-flight emissions to zero. But harnessing it means conquering storage challenges onboard aircraft. This survey dives into cutting-edge hydrogen tank technologies, exploring how to safely store gaseous or liquid hydrogen amid extreme pressures and frigid temperatures, all while integrating seamlessly into plane designs. By reviewing materials, structures, and innovations, it highlights hydrogen's role in aligning aviation with global sustainability goals, making eco-friendly flights not just a dream, but an impending reality.

Results and Benefits

This comprehensive review uncovers key advancements in hydrogen storage that promise to transform aviation. For gaseous hydrogen (GH2), high-pressure tanks made from advanced composites withstand internal pressures up to thousands of psi, while liquid hydrogen (LH2) storage tackles cryogenic conditions as low as -253°C with superior insulation to prevent boil-off. The survey spotlights materials like carbon fiber-reinforced polymers, which offer exceptional strength-to-weight ratios—crucial since hydrogen tanks can be four times larger than kerosene ones yet must not add undue weight. Experimental data from projects like the EU's Cryoplane initiative show that LH2 tanks achieve up to 70%–85% efficiency in hydrogen production via steam reforming, with potential jumps to 60%+ for green electrolysis methods using renewables.

Socially, these breakthroughs mean cleaner skies: hydrogen eliminates CO2 emissions during flight, potentially reducing aviation's climate footprint by 100% if produced greenly. Economic perks include lower operating costs once hydrogen prices match kerosene's around 2040, as projected in studies, with direct operating costs possibly dropping slightly under optimal conditions. Plus, safer designs incorporating structural health monitoring could cut maintenance hikes (estimated at 22%–32% initially) and enhance reliability, supporting 65.5 million jobs in aviation while fostering new industries in hydrogen production and infrastructure. Real-world tests, like the Soviet TU-155's hydrogen engine flights, prove feasibility, paving the way for reduced noise, better air quality, and a sustainable transport lifeline for global economies.

Future Application Prospects

Looking ahead, hydrogen tanks could revolutionize aircraft from short-haul commuters to long-range jets. Imagine retrofitting existing "tube-and-wing" planes with passively insulated cryogenic composite tanks, enabling quick adoption without full redesigns. For broader impact, unconventional aircraft shapes—like blended wings—could optimize LH2 storage, boosting range and efficiency. Further research should focus on cryogenic-resistant composites to minimize hydrogen embrittlement, where materials weaken under H2 exposure, and advanced insulation to curb thermal losses.

Practically, airports might integrate on-site green hydrogen production via solar or wind (with grid upgrades multiplying capacity 1.59 times), alongside storage matching three days' kerosene reserves. This could spawn hybrid systems blending hydrogen with biofuels or batteries, slashing NOx hotspots through better combustion mixing. Ongoing projects, such as those from companies like Airbus and Boeing, hint at commercial prototypes by 2030, with refinements in manufacturing processes potentially halving tank weights. Ultimately, these applications could decarbonize aviation entirely, inspiring similar shifts in shipping and automotive sectors for a greener planet.

Conclusion

This survey boldly underscores hydrogen tanks as a game-changer for sustainable aviation, blending innovative materials and designs to overcome storage hurdles and unlock zero-emission potential. By addressing embrittlement, insulation, and efficiency, it charts a path to aircraft that rival kerosene in performance while safeguarding our environment. As governments, researchers, and industry collaborate, hydrogen-powered flight isn't just innovative—it's essential for a thriving, eco-balanced future where the skies remain open to all.

Reference

Author: Sergio Bagarello ^a b, Dario Campagna ^a, Ivano Benedetti ^a b

Title of original paper: A survey on hydrogen tanks for sustainable aviation

Article link: https://www.sciencedirect.com/science/article/pii/S2773153724000768

Journal: Green Energy and Intelligent Transportation

DOI: 10.1016/j.geits.2024.100224

Affiliations:

^a Department of Engineering, University of Palermo, Edificio 8, 90128, Italy

^b Sustainable Mobility Center, Centro Nazionale per la Mobilità Sostenibile, MOST, Italy