Cut-Price Green Fuel Promise of “Turquoise” Hydrogen

Russian researchers have claimed they are able to split methane into hydrogen and solid carbon in a way that could be soon slash the cost of automotive grade hydrogen.

The researchers, from the Institute of the Problems of Chemical Physics (IPCP), applied a method called plasmo-chemical methane decomposition to produce so-called “turquoise” hydrogen. “This method has been known and used for production of different substances for at least 50 years,” said Yuri Dobrovolsky, head of the competence center of the National technological initiative at the institute. “However, it has never been optimized for production of hydrogen fuel.”

Unlike other methane decomposition methods, plasmo-chemical technology allows for relatively small-scale production, for example, at a hydrogen fueling station. The research team’s goal is to create and patent a compact production unit capable of producing up to 20kg of hydrogen which is enough to refill some three passenger cars or one bus per day at a price.

Green and blue is not turquoise

Hydrogen’s energy output is roughly three times that of gasoline and also fuel cells are twice as efficient in energy use than ICE. It means that hydrogen becomes a commercially viable fuel if its pump price doesn’t exceed that of 6kg of gasoline. Today, that is a big obstacle before mass uptake of green hydrogen obtained from water via electrolysis with the use of renewable energy sources. Except for the few locations where renewable energy supply is cheap and sufficient, its production cost is close to $10 per kg and that’s just the start. After compression and transportation, the pump price can reach $40 – too much, compared to gasoline’s roughly $1.1 per kg price in the US.

That is why three quarters of today’s global supply of hydrogen is, effectively, derived from natural gas while another quarter from coal via a method called steam methane reforming (SMR) at $1-3 per kg. However, SMR also produces vast amounts of carbon dioxide. Capturing it and applying the carbon tax multiplies the cost by two to three. Worse still, demand for technical CO2 is insufficiently high so the excess must be disposed underground, setting a time bomb for the future generations. “Provided that the threat of anthropogenic GHG emissions demands to upscale hydrogen production by several orders of magnitude as soon as 2035, SMR no longer matches the needs,” said Yury Melnikov, chief analyst of the energy center of Moscow School of Management Skolkovo.

In that respect, plasmo-chemical methane decomposition is a promising alternative for a number of reasons. It’s two to five times cheaper than electrolysis in terms of both electricity consumption or the production unit’s cost. Compared to SMR, it produces no impurities harmful for fuel cells. Instead of carbon dioxide, the process generates carbon as a by-product which can be used as raw material, driving hydrogen’s cost further down. “Our preliminary calculations show that its cost can be comparable to that of blue hydrogen,” Dobrovolsky said with many precautions. Some influencing factors yet remain unclear such as the future production unit’s service interval and lifespan.

The turquoise window

Eventually, the pump price of green hydrogen is going down. However, in many regions where renewable energy sources are scarce and natural gas supply infrastructure is well-developed, turquoise hydrogen will for years remain a preferred option, reducing impact on global warming thanks to eliminated emissions of CO2. It also opens a window of opportunities for countries, such as Russia, where hydrogen producers, currently, can produce only dirty grey hydrogen. Mikhail Ivanov, Russian deputy minister of industry and trade, said at exhibition Innoprom 2021: “They still need to take up carbon capture technologies.”

Before commercialization of turquoise hydrogen is possible, some technical issues still must be solved. “We are already able to split carbon from hydrogen and prevent it from depositing between the electrodes,” said Dobrovolsky. “Work still needs to be done on hydrogen purification and obtaining carbon in the form of homogenous fine powder. Most importantly, we still need to be able to extract carbon yield without interrupting the chemical reaction.”

Non-technical issues include finding new applications for solid carbon, expected to be generated as a by-product in large volumes, said Melnikov. Environmental footprint of methane production must be eliminated as well: “If the developers overcome that issues until 2030s and commercialize the technology, the chances are it will displace the SMR+CCUS combination.”

While a number of labs are globally working on these issues, there is no clear leader in this race. “I haven’t heard that anywhere in the world hydrogen was commercially produced this way,” Dobrovolsky said. “However, in the foreseeable future, I expect a number of technologies to be simultaneously presented by several companies.” He said that the IPCP team was hoping to present its pilot production unit in six months.

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