Oman could become world leader in geologic hydrogen

Eden

• Geologic hydrogen occurs naturally
• Oman has multiple sources
• Could cost just $1/kg

Green hydrogen has made global headlines as a potential carbon-free alternative to fossil fuels, but some experts believe another, abundant source of the gas could be under our feet. It is known as geologic hydrogen.

Geologic hydrogen occurs naturally in the earth’s crust and is produced when water reacts with iron-rich rocks in the subsurface.

Highly flammable, hydrogen and methane have been known to escape from a site in Turkey since antiquity. The perpetually burning flame it creates described in Homer’s The Iliad as a fire-breathing monster.

Yet hydrogen’s diffuse and hard-to-detect characteristics mean scientists have rarely tested for it – until recently.

• Adnoc opens region’s first green hydrogen refuelling station
• Oil and gas investments in Oman reach nearly $6bn
• Oman signs 9-year LNG supply deal with BP

For a 2020 research paper, Viacheslav Zgonnik, founder and CEO of Denver’s Natural Hydrogen Energy, conducted a study of Oman’s Western Hajar mountains. It uncovered sites where hydrogen was leaking from the ground at 73 to 147 cubic metres per square kilometre (m3/km2) from peridotite rock – a dense igneous rock. For rock from the Upper Proterozoic era, this increased to up to 1,300 m3/km2.

His work followed earlier research by other scientists in Oman. Overall, these various studies found hydrogen gas releases in the sultanate ranging between 22 and 99 percent purity.

Three-stage project

In September, Oman and US officials staged a joint workshop on the Gulf country’s geologic hydrogen potential in Muscat. This led to Massachusetts-based company Eden signing a memorandum of understanding with Oman to develop geologic hydrogen.

A major challenge is that naturally occurring hydrogen sources rarely emit the gas at commercially viable volumes.

Under the agreement, Eden has begun a three-stage project, having completed a pilot scheme with Oman’s state oil company in early 2023.

First, Eden will conduct a desk-based analysis of existing geological and other data to ascertain the optimal areas for geologic hydrogen within a broader region south and west of Muscat where formations of ophiolite rock – oceanic crust that has been uplifted and exposed – are located.

Next, Eden will drill exploration wells up to 600 metres deep in several locations to gather more data on the potential baseline hydrogen production levels from these seeps.

Finally, Eden will then perform what it describes as stimulation of hydrogen through its patented technology.

This will heat the temperature of the surrounding rock to 180-280C and pump water down the well and into the iron-bearing rock, as well as electrifying and fracturing it. This enhances naturally occurring chemical reactions between water and rock to produce greater quantities of hydrogen, as well as expanding the area in which this reaction occurs.

Another challenge will be to identify any bacteria present that consumes the hydrogen and to deploy chemical or bio-treatments to prevent this occurring. In all, these steps will take around two years to complete.

“Then, we can do a stimulated hydrogen demonstration,” said Ammar Alali, co-founder and president of Eden.

Ease of access

A Saudi national, Alali has a PhD in geophysics.

His company is in negotiations with Oman for a binding contract that will entitle Eden to expand its work in a similar fashion to the early stages of oil and gas exploration. Alali hopes the agreement could be signed by the end of December.

“These seeps undoubtedly emit hydrogen, but the question is whether they’re of commercial scale,” said Alali. “We won’t know for certain the size of the commercial opportunities until we complete our testing.

“Oman might have access to one of the largest prospects of geological hydrogen anywhere on the planet. Oman could become for geological hydrogen what Saudi Arabia is for oil and gas, where there’s not only huge, but also easy-to-access reserves.”

Eden

Eden believes its technology can increase the output of naturally occurring hydrogen by about 500 percent, enabling it to produce hydrogen at the wellhead – before transportation costs are included – of just $1 per kilogram.

“If we can do this, it will be a breakthrough moment for stimulated geological hydrogen,” said Alali.

Green hydrogen, in contrast, currently costs around $3.70 per kilogram to produce, according to consultants Rethink Energy. It deploys renewable energy to power electrolysers that split water into its base elements of hydrogen and oxygen.

Another drawback is that green hydrogen production consumes more energy than it produces, while Alali estimates geologic hydrogen will produce 11 times the energy it consumes.

“It can be much cheaper, too, because we don’t have to build these massive solar or wind farms or an electrolysis plant,” he said. “The capital expenditure is far lower.”

Alali said the Omani wells could produce up to 5 metric tonnes of geologic hydrogen annually per cubic kilometre of subterranean rock, citing a 2022 study by other scientists.

“Oman could become the cheapest source for geologic hydrogen,” he added.