The global energy crisis unfolding this year has renewed international interest in hydrogen’s potential as an alternative to fossil fuels across a wide range of industrial applications, from steelmaking to maritime transport. Although green hydrogen remains prohibitively expensive to produce, limiting its commercial adoption, gray and blue hydrogen also rely on the fossil fuels that many global markets are seeking to phase out. Nevertheless, a series of scientific breakthroughs is expanding the range of hydrogen production options, potentially helping overcome these obstacles, reduce carbon emissions and transform some of the hardest sectors to decarbonize.
Hydrogen has significant potential to replace fossil fuels in manufacturing and transportation because it can be burned at high temperatures, much like thermal coal or heavy fuel oil. Unlike these carbon-intensive fossil fuels, however, hydrogen produces only water vapor when burned. For this reason, green hydrogen, produced exclusively using renewable energy, has long been regarded as an important tool for supporting the global clean energy transition and reducing carbon emissions.
Cost barriers drive scientists to explore alternatives
However, ambitions for green hydrogen have yet to materialize as hoped. Separating hydrogen from water is expensive and highly energy-intensive. In many cases, producing hydrogen this way also represents an inefficient use of clean energy, which could be used more effectively through direct consumption.
Against this backdrop, a 2022 report by the International Renewable Energy Agency (IRENA) warned against the “indiscriminate use of hydrogen,” urging policymakers to carefully balance competing priorities. The report noted that widespread adoption of green hydrogen “may not be compatible with the requirements of a decarbonized world.”
However, a growing wave of funding for hydrogen research following the US-Israeli war against Iran has coincided with an important stage in several scientific projects seeking alternative ways to produce hydrogen while maintaining a low carbon footprint.
This week, a team of scientists at Oregon State University published a study revealing a new method for extracting green hydrogen from water using sunlight alone, through sulfur-based chemical reactions.
Compared with conventional methods of splitting water using electricity, “photocatalysis is a much more direct approach, relying on a material that is activated by sunlight and enters a high-energy state, allowing the same reaction to occur more rapidly,” according to a summary published by Interesting Engineering.
“Our work provides a blueprint for designing better materials that can lower the cost of green hydrogen,” Kyriakos Stylianou, a researcher at Oregon State University, said in a press release. “By changing the metal while keeping the rest of the material largely unchanged, we discovered why some metal-organic frameworks perform so much better than others. These findings provide new design rules for developing more effective materials for producing solar fuels.”
The discovery follows a separate scientific breakthrough at the Massachusetts Institute of Technology (MIT), where researchers developed an electrochemical process capable of extracting high-purity hydrogen from ammonia using a fraction of the energy required by conventional cracking, which involves temperatures exceeding 500 degrees Celsius.
Meanwhile, a study published in China in January revealed another method for producing green hydrogen at lower cost and greater efficiency by using sugars extracted from agricultural waste instead of oxygen in the hydrogen separation process. The method reduced production costs to $1.54 per kilogram, a level that could make green hydrogen cost-competitive with natural gas.
White hydrogen opens new possibilities
Perhaps the most significant and intriguing development in the hydrogen sector this year, however, is the potential emerging around so-called “white hydrogen,” also known as geological hydrogen.
Rather than producing hydrogen, this approach involves extracting it from naturally occurring deposits within the Earth’s crust. The technologies needed to release hydrogen from rocks where it has been trapped for millions of years are still under development, but the potential appears enormous.
The field has attracted interest from organizations including the US Geological Survey, which estimates that the Earth’s subsurface contains energy equivalent to approximately 170,000 years of current global oil consumption. The central question, however, is how much of these resources can actually be recovered and at what cost.
What appears clear is that momentum surrounding clean hydrogen has returned strongly after years of relative stagnation, and for good reason. Scientific evidence is mounting that the transition to clean hydrogen could follow multiple pathways, with one of these approaches potentially proving successful and ultimately reshaping the entire global energy landscape.
