Hydrogen fuel is often seen as a clean energy alternative because it doesn’t produce carbon dioxide when used.
However, most of the hydrogen we use today is made using fossil fuels, which release a lot of pollution during production.
That’s where a new process from MIT engineers could change everything—by using seawater and recycled soda cans to produce hydrogen in a much cleaner and sustainable way.
Last year, researchers discovered that aluminum from used soda cans can help generate hydrogen gas when mixed with seawater and treated with a small amount of a special metal mix called gallium-indium.
This simple chemical reaction breaks down water molecules, producing hydrogen and aluminum oxide. But the big question remained: could this method actually work on a large scale, and would it really be better for the environment?
Now, in a new study published in Cell Reports Sustainability, the team has shown that the process can work at an industrial level—and that it produces far less carbon pollution than traditional hydrogen-making methods.
Using a detailed “life cycle assessment,” the researchers looked at the entire process—from collecting aluminum and producing hydrogen to delivering it to fueling stations—and calculated how much carbon dioxide would be created along the way.
They found that producing one kilogram of hydrogen using this aluminum method would emit just 1.45 kilograms of carbon dioxide.
That’s a major improvement compared to the 11 kilograms of CO₂ produced for every kilogram of hydrogen made using fossil fuels. In fact, this new method matches the low emissions of other “green hydrogen” technologies like solar or wind-powered systems.
Recycling plays a big role in reducing emissions. The team found that using recycled aluminum—such as soda cans—dramatically cuts down the environmental impact compared to mining fresh aluminum.
The salt in seawater also helps in recovering the gallium-indium mix, which can be reused, making the process more cost-effective and sustainable.
The process also creates a byproduct called boehmite, a mineral useful in electronics and other industries. Selling this byproduct could help lower the overall cost of producing hydrogen even more.
To make things even more practical, the team developed a small reactor, about the size of a water bottle, that mixes aluminum pellets and seawater to create hydrogen. This tiny reactor can produce enough hydrogen to power an electric bike for hours. They’ve even demonstrated it can fuel a small car and are now exploring ways to power boats or underwater vehicles directly from the ocean.
The researchers imagine a future where aluminum pellets, treated and ready to go, are shipped to hydrogen fueling stations located near the coast. There, the pellets could be mixed with seawater on demand to make hydrogen, which would then be pumped into fuel cell cars. This setup avoids the dangers of transporting hydrogen itself, which can be unstable.
The team’s work shows that making clean hydrogen using everyday waste like soda cans and ocean water isn’t just possible—it could be a major step forward in solving both our energy and environmental challenges.
