Hydrogen has long been claimed as one of several possible energy sources that might play a pivotal role in the energy transition, but the scarce element comes with a carbon footprint that does not justify the cost of producing it. Nearly all hydrogen is currently produced as grey using fossil fuels, which emit significant amounts of greenhouse gases, or delivered in its green form using prohibitively costly renewable power. However, a global rush is underway for one other previously neglected colour in the hydrogen rainbow that supporters believe might make a critical difference in the transition away from fossil fuels. Speaking at the inaugural Geneva Dry event about possible shifts in future coal trades earlier this month, Hamish Norton, president of bulker giant Star Bulk Carriers, entertained an idea of geologic hydrogen. Geologic hydrogen, often known as white, gold, or natural hydrogen, is a gas that originates naturally beneath the Earth’s surface from high-temperature interactions between water and iron-rich minerals. It is currently poorly understood, but, according to Norwegian energy intelligence firm Rystad, it could be a potentially groundbreaking energy resource if scientific claims of multiple large deposits of possibly hundreds of years’ worth of energy reserves worldwide can be tapped into. Preliminary research by the US Geological Survey (USGS) estimates up to 5trn tonnes of geologic hydrogen may exist in various rock formations but that they are too deeply buried, too far offshore, or in accumulations that are too small, making it highly unlikely they could ever be economically recovered. Nevertheless, Geoffrey Ellis, a petroleum geochemist with the Energy Resources Program of the USGS, said that even if just a few percent of that estimated volume could be recovered, it would likely be enough to supply all projected demand for hundreds of years. “The key,” he said, “is to understand if hydrogen exists in significant accumulations that can be economically accessed, and if so, how to find these resources.” Geological hydrogen extraction is in its infancy. But if it scales over time, including by utilising the oil and gas industry’s infrastructure expertise, it could provide an additional source of zero-emissions fuel to power the next generation of heavy duty transport including shipping. Most hydrogen today, however, is manufactured using natural gas, requiring large amounts of energy and releasing carbon dioxide that is often left unabated. Current methods for reducing the carbon footprint of producing hydrogen include capturing and storing the carbon dioxide produced, and getting the so-called blue hydrogen in the process, which is more costly than traditional hydrogen manufacturing. Looking at the hype surrounding geologic hydrogen, the gas is on the verge of a scenario that resembles a new gold rush, promising it could potentially rewrite the world’s energy map but also commodities shipping, such as coal, oil/products and other energy sources. “If China turns out to have a lot of that, and it may, we may see a more rapid reduction in coal consumption,” Star Bulk’s Norton pointed out at the dry bulk supply chain gathering in Geneva. Rystad Energy research showed that at the end of last year, 40 companies were searching for natural hydrogen deposits, up from just 10 in 2020. One of the most promising qualities of the potential fuel is its lower cost than other types of hydrogen due to its natural occurrence. Grey hyd