Australian Engineers Turn CO2 Into Fertilizer Using Solar

A team of engineers in Sydney just figured out how to turn two environmental problems into food for half the world.

Researchers at UNSW Sydney developed a new way to make urea, the fertilizer that feeds crops for more than half the global population. Instead of relying on natural gas or coal like traditional factories do, they're using waste carbon dioxide and nitrogen pollutants powered by renewable electricity.

Associate Professor Rahman Daiyan and PhD student Putri Ramadhany led the work, which was recently published in Nature Communications. They designed a catalyst made from copper and cobalt that bonds carbon and nitrogen molecules together at the atomic level.

"Making carbon and nitrogen bond together in a controlled and reliable way is extremely difficult," Ramadhany explains. The catalyst holds the molecules together just long enough for them to react and form urea.

The process tackles two major pollution sources at once. Industrial activities released around 40 billion tons of carbon dioxide in 2024 alone, while nitrogen pollutants from agriculture contaminate waterways worldwide.

Traditional urea production requires extreme heat and pressure in fossil fuel powered plants. This new method runs at normal conditions using solar or wind power, cutting emissions dramatically.

The Ripple Effect

The technology addresses a surprising vulnerability for Australia. Despite being a major agricultural exporter, the country imports around 3.8 million tons of urea annually because it doesn't produce enough domestically.

"This dependence is a pity as well as a strategic vulnerability," Daiyan says. Local production from waste carbon and renewable electricity would strengthen supply chains while lowering emissions.

The team isn't stopping at lab experiments. They're already testing the process in urea electrolysers, the industrial equipment needed for real world production. Using advanced imaging at the Australian Synchrotron, they watched the chemical reactions happen in real time to understand how the materials perform under actual working conditions.

Daiyan emphasizes they're targeting unavoidable emissions from cement factories and agricultural waste rather than trying to capture carbon from thin air. The approach focuses on waste streams that already exist.

The timeline for bringing this to market looks promising. While most lab technologies take over a decade to reach industry, Daiyan expects to partner with commercial producers within two to three years.

He recently presented the work at COP30, the United Nations Climate Change Conference, as an example of circular economy thinking. "There's enough carbon dioxide around," he told government representatives. "We just need to start thinking and investing in a circular economy."

The breakthrough shows how clever engineering can flip problems into solutions, turning pollution into products that help grow the food the world needs.