How hydrogen can help decarbonize global industry

Posted: October 06, 2025

With industries around the world facing mounting pressure to decarbonize, a wide range of possible applications for hydrogen have been developed or explored. Hydrogen, the most abundant chemical element in the universe, has proven to be a versatile clean energy carrier and industrial feedstock; when converted into usable energy in a fuel cell, it only produces water as a byproduct. Global hydrogen demand reached nearly 100 megatons last year and is expected to continue growing into 2025.

When that hydrogen is “green”—that is, when it has been produced using renewable energy sources like wind or solar as opposed to fossil fuels—it holds the potential to vastly diminish the carbon intensity of products and processes in a range of industrial sectors, from oil refining and chemicals production to transportation and building. Some of these applications are more mature and more economically practicable than others. With innovation continuing apace, however, it seems likely that green hydrogen will play a major and multifaceted role in the decarbonization of industry moving forward.

Established use cases in the petrochemical and chemicals industries

Currently, the majority of demand for hydrogen—and thus the majority of potential demand for green hydrogen—lies in oil refineries and ammonia and methanol production.

Oil refineries use hydrogen in vital steps such as the hydrotreating of crude oil, whereby hydrogen reacts with impurities like sulfur and nitrogen to remove the contaminants from the hydrocarbons, and in the hydrocracking process that converts heavy oil fractions into middle distillates and light products like diesel and naphtha. Almost all hydrogen consumed in oil refineries today is derived from fossil fuels, but these facilities are well positioned to adapt to green hydrogen, including through the integration of low-emission hydrogen production directly into the refinery. It has been proposed that green hydrogen could be used in these two major processes, thereby reducing carbon emissions by a notable extent.

Hydrogen is also in great demand for the production of ammonia, an important chemical and agricultural product often used in fertilizers that—according to the WEF in 2023—accounts for over 1% of global energy-related CO2 emissions.  Typically, fossil fuels are used to provide both the hydrogen and the energy required to make ammonia from hydrogen and nitrogen via the Haber-Bosch process.

Using renewable energy and green hydrogen to create green ammonia has massive decarbonization potential. Green ammonia has also been discussed as a possible means for storing and transporting energy. The production of methanol in the chemicals industry, too, might offer the opportunity for green hydrogen to contribute to further decarbonization. Most methanol today is manufactured via steam methane reforming—a carbon-intensive process that uses natural gas and steam to produce a syngas used for methanol production—but it can also be synthesized by combining green hydrogen with captured carbon dioxide, thus producing what is sometimes known as “green methanol.”

Hydrogen for heavy industry: steel, cement and beyond

Hydrogen may also have a major role to play in the decarbonization of iron and steel production. One of the most promising and widespread technologies for reducing carbon emissions involves the use of “direct reduced iron” (DRI). This product can be used as a feedstock for steel-making in place of pig iron, which is typically produced by heating iron to its melting point in a coal-powered blast furnace. DRI, by contrast, is made by removing oxygen from iron ore by use of a gas—thus avoiding the need to melt the iron. This gas is often natural gas, but it is also possible to use green hydrogen in its place.

Australia, the world’s largest producer of iron ore, has announced a major initiative with the aim of making that nation “the center of the global green iron market.” It is very likely that those plans will require the use of green hydrogen in iron-making, although the types of iron involved and the cost of renewable hydrogen may present obstacles.

The hard-to-abate cement industry, too, offers possibilities for the adoption of green hydrogen. Substituting green hydrogen for carbon-intensive alternatives in the fuel mix and introducing hydrogen-based carbon capture technologies both offer potential sustainability gains. While the high temperatures required for producing clinker are usually achieved by burning fossil fuel products, it seems increasingly plausible that hot-burning hydrogen—which combusts carbon-free—can complement other measures to decarbonize the sector.

Additionally, green hydrogen has been proposed for use in the glass-making industry, taking advantage of its high flame temperatures and ability to be blended in gradually along with natural gas. The European H2GLASS initiative aims to design, test and validate totally hydrogen-fueled furnaces, while Air Liquide has announced its tests show that 50% of natural gas can already be replaced by hydrogen without affecting the quality of glass or the furnace’s industrial performance.

Power and transport: Where hydrogen fits (and doesn’t)

Since it is possible to store excess renewable electricity in hydrogen through electrolysis and then convert it back to power without releasing new emissions, it has been suggested that hydrogen could play an enabling role in the overall shift toward renewables by stabilizing power grids that use a lot of wind or solar. Hydrogen can indeed be used to capture and store ‘curtailed’ electricity, which is generated when renewables produce more than the grid can absorb and would often be otherwise lost. Overall, it seems unlikely that hydrogen will be able to outperform batteries or hydropower storage, which remain considerably more efficient at energy conversion—yet it may end up contributing under certain specific circumstances and only in combination with other grid storage techniques.

In difficult-to-abate industries like heavy trucking and transportation, hydrogen has a clear decarbonization potential. Maritime shipping and aviation both have limited practical low-carbon fuel options, which makes hydrogen-based fueling solutions more appealing. Direct hydrogen use and synthetic fuels have both been explored for aviation. In maritime shipping, which accounts for some 3% of global carbon dioxide emissions, the potential for hydrogen-based fuels is considerable—despite the challenges associated with transportation. In 2023, the IEA estimated that hydrogen could grow from current levels of under 1% of total energy used in shipping to 19% by 2050.

For railways, hydrogen fuel cells could provide energy that counts as emissions-free at the point of use while offering more energy density and requiring less up-front infrastructure compared with electric trains. Since Germany launched the world’s first hydrogen-powered train in 2018, programs have been announced in Europe and the UK as well as in San Bernardino, California, home to the first hydrogen-powered, zero-emission passenger train in North America. Regional governments in France have commissioned 12 hydrogen trains from the company Alstom, which will also provide 14 trains to initiatives in northern Italy next year.

When it comes to the road, hydrogen fuel cells have certain advantages and disadvantages compared to battery-powered electric technology. Hydrogen, which is typically transported on the vehicle, is comparatively light, while hydrogen vehicles can be refueled considerably faster than batteries can be recharged. Yet the battery option has considerable advantages in efficiency—not to mention better refueling infrastructure in most places.

As it stands, hydrogen seems likely to make more of an impact in heavy trucking, an industry where battery-based solutions have struggled to meet the challenges posed by long routes and an aversion to carrying large heavy batteries. Toyota, Volvo and Daimler Truck have all been active in the space, while TotalEnergies has partnered with Air Liquide to develop a network of 100 hydrogen truck refueling stations across Europe.

Green hydrogen may also help to decarbonize space transportation, an industry that makes extensive use of liquid hydrogen as fuel for rockets. The European Space Agency has begun an initiative to transition its Spaceport in French Guiana to hydrogen produced locally using solar electrolysis. Honda plans to test a sustainable hydrogen fuel cell system at the International Space Station.

For green hydrogen to really take off worldwide, it requires economies of scale to push down the price as well as the appropriate governmental support. If these are put in place, then not even the sky might be the limit for hydrogen-powered decarbonization.