Tapping into Earth's Natural Hydrogen Reserves

• Gold hydrogen, or naturally occurring hydrogen, has been discovered in numerous locations worldwide and could be extracted in large quantities, offering a clean energy source for industries reliant on high-heat fuels.
   
• Producing green hydrogen requires significant amounts of renewable energy, potentially making it counterproductive for achieving decarbonization goals, while gold hydrogen bypasses the need for energy-intensive production processes.
   
• Despite the excitement surrounding gold hydrogen, it remains largely untested, and concerns exist regarding its environmental impact, potential for fossil fuel discovery, and misuse for greenwashing.
   

 Many climate experts and energy industry insiders believe that hydrogen will be an essential part of achieving global climate goals because of its utility in hard-to-decarbonize heavy industry. Hydrogen can be burned at high heat like fossil fuels, but unlike coal, oil, or natural gas, it leaves behind nothing but water vapor when combusted. This makes it a very attractive alternative for industries that rely on hot-burning fuels like thermal and coking coal, and could potentially transform the steelmaking and shipping industries, just to name a couple of heavy hitters.

The potential benefits of a wide-scale replacement in high-heat industrial applications are difficult to overstate. “Replacing the fossil fuels now used in furnaces that reach 1,500 degrees Celsius (2,732 degrees Fahrenheit) with hydrogen gas could make a big dent in the 20% of global carbon dioxide emissions that now come from industry,” Bloomberg Green wrote in a report titled “Why Hydrogen Is the Hottest Thing in Green Energy.”

There’s just one problem. Creating hydrogen for these kinds of industrial applications is energy intensive, and the resulting hydrogen is only as green as the energy source used to make it. Hydrogen is already widely used in heavy industry today, but the vast majority of it is produced using fossil fuels (known as ‘gray hydrogen’), which defeats the purpose of using it for decarbonization. ‘Blue hydrogen’, which refers to hydrogen produced using natural gas, yields lower emissions than other fossil fuels and is seen by some as a stepping stone to full decarbonization. But the real buzz is around green hydrogen, which is produced using renewable energy and is therefore seen as a clean energy source that could be integral to the global clean energy transition.

There is a serious downside to green hydrogen, however. A 2022 report from the International Renewable Energy Agency (IRENA) warned against the “indiscriminate use of hydrogen,” arguing that extensive use of hydrogen “may not be in line with the requirements of a decarbonised world.” In particular, the report argues that producing green hydrogen requires vast amounts of clean energy that may be better used in other applications, making the mass production of green hydrogen counterproductive for reaching climate goals.

But now a new color has been added to the hydrogen rainbow, and it could completely sidestep the issues faced by existing forms of hydrogen production. Gold hydrogen (also sometimes referred to as white hydrogen) is the name being used to refer to hydrogen which is naturally occurring in certain geological areas of the world (subsurface geologic accumulations, to be exact), sometimes in vast quantities. It’s produced underground when water chemically reacts with iron-rich rocks or radioactive minerals. And it’s the new holy grail of hydrogen exploration. 

This kind of hydrogen was previously dismissed as fictional at worst or untappable at best, but in the last few years “reservoirs have been discovered in the United States, Canada, Finland, the Philippines, Australia, Brazil, Oman, Turkey and Mali, leading would-be gold diggers to believe that there are numerous sources waiting to be discovered,” Reuters recently reported. According to one estimate published in Earth-Science Reviews back in 2020, we could be extracting 23 million tons of hydrogen from the ground each and every year. And there’s already a new wave of startups looking to do just that.

One such startup, Natural Hydrogen Energy (NH2E), was founded by Viacheslav Zgonnik, the chemist who wrote the 2020 Earth-Science Reviews paper. Zgonnik thinks that the potential for gold hydrogen extraction is even greater than his paper, which is based on a conservative estimate of existing tappable reserves, suggests. “That is the currently available estimate of generation of geologic hydrogen from the ground but, in my opinion, the real number should be two to three orders of magnitude higher because we still don't know a lot about the hydrogen system and have very scarce measurements of hydrogen on the planet,” he told Reuters.

Not everyone is as optimistic as Zgonnik, however. Reporting on gold hydrogen is couched in caveats, and while there is a lot of excitement about the fuel’s potential, it’s just far too early to declare that gold hydrogen will be a silver bullet for the climate. It’s almost completely untested – at present, the village of Bourakébougou in Mali has the only place in the world with a functioning hydrogen well already being used as a fuel source. 

Furthermore, there needs to be a whole slew of studies conducted to determine exactly how clean this underground hydrogen is. Many scientists are concerned that when we extract this stored hydrogen, we will release greenhouse gasses along with it. Others worry that hydrogen exploration will lead to the discovery – and use – of new fossil fuel reserves. Still others think that gold hydrogen will be misused for greenwashing purposes á la carbon capture.