What is turquoise hydrogen?

You’ve heard of grey hydrogen, blue hydrogen and green hydrogen. But what about turquoise hydrogen? Turquoise hydrogen offers all the advantages of grey, blue and green hydrogen -- without their drawbacks.

Quick refresher. There are several ways to produce hydrogen, and their impacts on the environment are not the same:

·??????Grey hydrogen is mainly produced from coal gasification or natural gas via steam reforming.

·??????Blue hydrogen is the same thing, with carbon capture at the end.

·??????Green hydrogen is made from water using electrolysis.

·??????Turquoise hydrogen is made from methane natural gas or biomethane, through a process called plasmalysis, which uses charged particles to break down methane molecules into hydrogen atoms and carbon atoms.

The problems with grey and blue hydrogen

Grey hydrogen is very cost-efficient to produce, but there is a very big downside: It is a significant contributor to greenhouse gas emissions, because steam reforming creates carbon dioxide (CO2) as a by-product. In fact, for every ton of grey hydrogen produced, more than 10 tons of CO2 are released into the atmosphere! Grey hydrogen production also releases a bit of methane (CH4), a greenhouse gas whose negative impact on the quality of the atmosphere is estimated to be up to 86 times greater than CO2 over 20 years.

Blue hydrogen was industry’s first attempt to produce hydrogen in a more environmentally friendly way. Blue hydrogen is produced just like grey hydrogen, but with the addition of CO2 capture and storage to reduce emissions. It’s a good idea, but unfortunately, those capture and storage processes are only about 70% to 85% efficient overall… and that means blue hydrogen still emits some greenhouse gasses.

Green hydrogen to the rescue … or not?

Enter green hydrogen, produced by splitting water molecules into hydrogen atoms and oxygen atoms using an electrical current, a method known as water electrolysis. That process itself does not emit any greenhouse gasses; and if the electricity used to power the electrolyzers is generated from renewable sources, the entire green hydrogen production process tends to be carbon-free.

It sounds great in theory … but unfortunately, green hydrogen production has some drawbacks.

First of all, green hydrogen is expensive right now, both in terms of the cost of producing the large amounts of electricity required for water electrolysis, and the cost of the equipment and infrastructure needed to produce, transport and store it.

But perhaps more importantly, green hydrogen requires a steady supply of very large quantities of water. This has serious implications. Water is a precious raw material, and one that is absolutely necessary for both human life and peace on earth. It is also a resource that is not always readily available.

The advantages of turquoise over green

Turquoise hydrogen produced by methane plasmalysis presents a number of concrete advantages over green hydrogen produced by water electrolysis.

Turquoise hydrogen is much more energy efficient than green hydrogen. Methane plasmalysis requires five times less energy than water electrolysis, because it takes much less energy to split a methane molecule (75 kJ/mol) than it takes to split a water molecule (570 kJ/mol) to produce the same amount of hydrogen.

Producing turquoise hydrogen locally instead of importing green hydrogen can be a more ethical and environmentally-sound decision, because many countries currently positioning themselves as green hydrogen exporters suffer from water shortages and outright droughts – for example, Middle Eastern countries, Morocco, Chile, and even China and Australia.

But perhaps most importantly, turquoise hydrogen is always carbon neutral and sometimes even carbon negative:?

Turquoise hydrogen can be made from natural gas, which is a carbon-containing fuel. By converting that natural gas into hydrogen instead of combusting it, the greenhouse gas emissions that would have occurred from burning it are eliminated before they even happen.

Turquoise hydrogen can also be made from biomethane, a renewable fuel produced by the breakdown of organic matter such as agricultural waste, food waste and animal manure. Biomethane has a negative carbon footprint because it is derived from the CO2 that plants remove from the air during photosynthesis. Performing plasmalysis on biomethane instead of using it in combustion processes contributes meaningfully to the reduction of CO2 in the atmosphere, removing between 10 and 12 kilograms of CO2 for every kilogram of hydrogen produced.?

I believe in turquoise hydrogen

Confession time: I’m not a neutral observer of the turquoise hydrogen phenomenon.

Sakowin, the company I founded in 2017 and have the great honor of leading today, is a pioneer in using methane plasmalysis to produce hydrogen.

Sakowin’s patented equipment for energy-efficient, cost-efficient, on-site, on-demand hydrogen production can be integrated into existing industrial and gas infrastructures. We are also working on ways to help our customers sell the solid carbon by-product.

We have already raised over 8 million euros. We have the support of the European Innovation Council, the European Union’s flagship innovation program. In March 2022, Bpifrance qualified us as one of their official Deeptech companies. ?

I’m proud of the work we do at Sakowin and our contribution to accelerating the energy transition -- and I hope I’ve piqued your interest in turquoise hydrogen.

?

Contact us at Sakowin

Connect with me or someone else on the team at Sakowin. We’d love to talk with you about how our turquoise hydrogen solution could be integrated into your current industrial or gas infrastructure.

?

?

/ / /

?

Sources of the facts and figures cited in this article

• Dean JF. Old methane and modern climate change. Science. 2020 Feb 21;367(6480):846-848. doi: 10.1126/science.aba8518. PMID: 32079756
• Fulcheri, Laurent. (2022). “Turquoise hydrogen, a viable solution without CO2 ?”. Polytechnique insights. https://www.polytechnique-insights.com/en/columns/energy/turquoise-hydrogen-a-viable-solution-without-co2/
• Gravimetric energy density figures: U.S. Department of Energy / U.S. Energy Information Administration
• Howarth, RW, Jacobson, MZ. (2021) “How green is blue hydrogen?” Energy Science & Engineering. 2021; 9: 1676– 1687. https://doi.org/10.1002/ese3.956
• McFarland, Eric. (2021) “Whether green, blue, or turquoise, hydrogen needs to be clean and cheap” Bulletin of the Atomic Scientists. https://thebulletin.org/2022/01/whether-green-blue-or-turquoise-hydrogen-needs-to-be-clean-and-cheap/
• Rastogi, M., & Yadav, A. K. (2018). “Recent developments in water electrolysis for hydrogen production: A review.” Renewable and Sustainable Energy Reviews, 82, 2970-2984. https://doi.org/10.1016/j.rser.2017.11.001
• Wang, Y., & Han, X. (2020). “Advanced materials for efficient hydrogen production via water electrolysis.” Energy Conversion and Management, 219, 113085. https://doi.org/10.1016/j.enconman.2020.113085
• Zhang, Y., Shao, L., Cao, Y. et al. (2021) “Energy and environmental analysis of hydrogen production pathways: A review and multi-criteria decision-making.” Energy & Environmental Science. 2021, 14, 148-174