Giant Floating Islands That Turn Atmospheric CO2 into Fuel Could Prevent Climate Change, Scientists Say

Millions of floating islands that convert atmospheric carbon dioxide to fuel could help protect our climate from the burning of fossil fuels, scientists have said. These proposed islands would be clustered together to create large-scale facilities that—if enough were built—could eventually offset the total global emissions from fossil fuels.

A team of researchers from Norway and Switzerland has put forward a proposal for 'Solar Methanol Islands' in a paper published in PNAS. The article argues that most of the technology to build these facilities already exists, and that by creating them on a large scale in ocean regions where they would be safe from large waves and extreme weather, we could drastically reduce the need for fossil fuels, thereby limiting the extent of global warming over the coming decades.

"Humankind must cease CO2 emissions from fossil fuel burning if dangerous climate change is to be avoided," they wrote. "However, liquid carbon-based energy carriers are often without practical alternatives for vital mobility applications. The recycling of atmospheric CO2 into synthetic fuels, using renewable energy, offers an energy concept with no net CO2 emission."

Study author Andreas Borgschulte told Newsweek that one of the main problems with renewable energy is making it competitive with fossil fuels on a large scale. Several concepts have been put forward to try to make renewables a realistic option, but nothing has yet found its way to fruition. He said the idea for the solar islands came when the Norwegian researchers were asked by the government to push fish farms out to open sea. These grids, however, needed their own energy. "Energy 'producing' islands had been proposed some time ago," he said. "What remained was to include energy storage."

In the paper, the researchers suggest floating islands similar to large-scale floating fish farms. They would use photovoltaic cells that could convert solar energy into electricity. This would then power hydrogen production and CO2 extraction from seawater. The gasses produced would then be reacted to form methanol that can be reused as a fuel, "which is conveniently shipped to the end consumer," they wrote.

Solar methanol island
Artist impression of a 'solar methanol island' that could convert atmospheric CO2 into fuel. NOVATON Erneuerbare Energien AG

The team says 70 of these artificial islands would make up a single facility that covers an area of around one kilometer squared (0.4 square miles). Facilities could be placed in areas where wave height reaches less than seven meters, where there is a low probability for hurricanes and the water depth is less than 600 meters, so the islands can be moored properly. Locations for facilities were found across the globe, with the coasts of South America, Australia and Southeast Asia particularly suitable.

The team estimates that the output from 3.2 million floating islands would exceed the total global emissions from fossil fuels.

Production is still some way off and the team acknowledges that the proposal is "ambitious." At the moment, they are working to develop prototypes of the floating islands.

"[The] biggest challenge is the development of a large scale device to extract CO2 from seawater," Borgschulte said. "This process is the only one of the total system [that] has not yet been fully developed. All others exist already on an industrial scale."

Peter Edwards, Professor of Inorganic Chemistry at the U.K.'s University of Oxford, who was not involved in the research, said that while the science behind the study was sound, there are huge technological hurdles to overcome. He told Newsweek that while the authors recognize and acknowledge this to an extent, "I think the challenges extend way beyond what they see, not least the question of how the materials—solar panels—will survive in the ocean environment (chemical and physical), and how the petrochemical plant would really work at the desired scale with the type of maintenance required on an off-shore platform."

However, Edwards also said the proposal should not be discounted "as long as reputable scientists and engineers are engaged to address the real issues."

This article has been updated to include quotes from Peter Edwards.