California-based start-up C-Zero is to build a turquoise hydrogen pilot plant in the US after securing $34m of investment from French utility Engie, Singaporean energy trader Trafigura and SK Gas, a subsidiary of South Korea’s second-largest conglomerate, SK.

Hydrogen: hype, hope and the hard truths around its role in the energy transition
Will hydrogen be the skeleton key to unlock a carbon-neutral world? Subscribe to Accelerate Hydrogen, powered by Recharge and Upstream, and get the market insight you need for this rapidly evolving global market.

The plant, which will be built at an undisclosed location but is expected to be on line in Q1 2023, will produce about 146 tonnes of turquoise hydrogen per year by splitting methane into hydrogen and solid carbon using a process known as pyrolysis.

Natural gas will be heated to high temperatures in the absence of oxygen inside pyrolysis ovens, breaking CH4 into its constituent elements, without allowing the carbon molecules to bond with oxygen in the air and thus create CO2.

C-Zero has previously secured investment from the billionaires-backed Breakthrough Energy Ventures, Italian oil company Eni, Japan’s Mitsubishi Heavy Industries and London-based venture-capital firm AP Ventures.

“Natural gas provides a quarter of the world’s energy, so the scale of the opportunity ahead of us is enormous,” said C-Zero’s chief technology officer Eric McFarland. “But we cannot do it alone.”

Turquoise hydrogen — the name given for H2 produced via pyrolysis — is said to be emissions-free, although that does not take into account upstream emissions of methane, which is 86 times more powerful a greenhouse gas than carbon dioxide. The US has the third-worst rate of methane emissions in the world, according to its own Energy Information Administration.

But C-Zero states: “When renewable natural gas [ie, purified biogas] is used, the process is carbon negative, effectively extracting carbon dioxide from the atmosphere and storing it as solid carbon.”

There are many companies around the world developing turquoise hydrogen, but the current market leader is probably Nebraska-based Monolith, which produces 5,000 tonnes a year at present, but has received conditional approval for a $1.04bn loan guarantee from the US Department of Energy to expand its manufacturing facilities to 50,000 tonnes per year.

Incidentally, last October, SK signed a memorandum of understanding with Monolith to pursue a joint venture for producing turquoise hydrogen and carbon black (a form of solid carbon) in South Korea.

“We see significant applications for low-carbon hydrogen production through methane pyrolysis which complement Engie’s existing activities and skill sets. Investing early on in C-Zero’s journey brings us familiarity with the technology, and could help Engie achieve its goal of Net Zero by 2045” said Johann Boukhors, Managing Director of Engie New Ventures.

Byung Suk Yoon, CEO of SK Gas, added: “We are eager to bring C-Zero’s technology to Korea, where we see great synergies with our plans to build a hydrogen value chain complex in Ulsan. SK Gas strongly believes in the potential of methane pyrolysis and its ability to help countries like Korea in their decarbonisation efforts by producing low-cost, clean hydrogen.”