A team at the Massachusetts Institute of Technology (MIT) has unveiled a method to produce hydrogen fuel that could significantly cut both costs and carbon emissions. This new process uses recycled aluminium and seawater to generate hydrogen through an aluminium-water reaction (AWR), offering a potential alternative to the carbon-intensive methods currently used in hydrogen production.

Conventional hydrogen generation relies largely on steam methane reforming, which emits between 9 and 12 kilograms of carbon dioxide for every kilogram of hydrogen produced. Even the cleaner alternative—green hydrogen produced via electrolysis powered by solar or wind energy—remains expensive and resource-heavy.

The MIT method is built around the aluminium-water reaction, in which aluminium reacts with water to produce hydrogen gas, heat, and aluminium oxyhydroxide. Aluminium is an attractive option due to its abundance and high energy density, offering twice the volumetric energy of diesel.

A key challenge in utilising this reaction lies in aluminium’s natural oxide layer, which prevents effective contact with water. MIT addressed this by coating recycled aluminium pellets with a gallium–indium alloy. This coating removes the oxide barrier, allowing the reaction to proceed efficiently with seawater.

Life-cycle analysis conducted using MIT’s Earthster tool shows that the process emits just 1.45 kilograms of CO₂ per kilogram of hydrogen—comparable to the cleanest electrolysis technologies and substantially cleaner than fossil-based methods. The estimated cost of hydrogen production using this technique is approximately USD 9.20 per kilogram, which aligns with current green hydrogen solutions.

In addition to hydrogen, the process also produces boehmite, a form of aluminium oxide with high commercial value in the semiconductor and industrial sectors. The sale of boehmite could significantly enhance the economic viability of the process, potentially increasing profitability fivefold.

MIT researchers have already built a working prototype of a “hydrogen reactor” about the size of a water bottle. This device is capable of powering an electric bicycle for several hours. Future iterations are envisioned for powering small boats and underwater vehicles—particularly useful in remote or off-grid environments where infrastructure is limited.

An important advantage of this system is its logistics and safety profile. Instead of transporting and storing pressurised hydrogen gas, the system uses solid aluminium pellets, which release hydrogen only when needed. The gallium–indium alloy used to activate the reaction can also be recovered and reused, adding to the sustainability of the process.

Using recycled aluminium further amplifies the environmental benefits. Producing recycled aluminium requires only about 5 per cent of the energy needed to make new aluminium, significantly cutting emissions. With cleaner smelting methods and more efficient transportation, total emissions could be reduced by up to 25 per cent.

This development builds on earlier research by MIT, which explored the feasibility of using aluminium, seawater, and even caffeine as inputs for hydrogen production. The new work represents a significant step forward in demonstrating how scrap metal and seawater can be transformed into clean, on-demand hydrogen energy.

MIT's research team is now focused on scaling the technology and testing it in real-world scenarios, including transportation, marine applications, and remote energy systems. If successful, this aluminium-based pathway could become a practical and scalable solution for low-emission hydrogen deployment worldwide.

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MIT unveils a cost-effective green hydrogen production tech from recycled aluminium and seawater