Millions of floating islands, clustered together, that convert carbon dioxide to methanol fuel could help reduce the number of greenhouse gases in the atmosphere, according to researchers from Norway and Switzerland.
The team has put forward a proposal for “solar methanol islands” in a paper published in the Proceedings of the National Academy of Sciences journal, PNAS.
Within the article, they agree that a massive reduction in carbon dioxide emissions from fossil fuel burning is required to limit the extent of global warming. However, carbon-based liquid fuels will continue to be important energy storage media in the foreseeable future. They propose a combination of largely existing technologies to use solar energy to recycle atmospheric carbon dioxide into liquid fuel.
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 carbon dioxide extraction from seawater. The gasses produced would then be reacted to form methanol that can be reused as a fuel.
“[The] biggest challenge is the development of a large scale device to extract CO2 from seawater,” Borgschulte told Newsweek. “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.”
Henry Snaith, Professor of Physics at Oxford University, who was not involved in the research, told Forbes, “I don’t think the idea is totally bonkers, but I also don’t think it’s the world-saving concept its bid to be.”
The Floating solar farms aren’t a new idea, but the challenge is making this floating deployment as cost competitive as rigid deployments. At present – location dependent obviously – land cost still only remain a small fraction of the total deployed PV (photovoltaic) cost. Only this week, the Dubai Electricity and Water Authority announced it was thinking about developing floating renewable energy plants in the Persian Gulf and launched a search for consultants who can advise it on the idea.
“PV is cheap today though, so the statement that alternatives can’t compete with fossil fuels is entirely incorrect,” Snaith said. “In fact, from now on, more new generation capacity [generators] will be [from] renewables – primarily wind and solar – than traditional thermal power stations.
“The other components needed for the idea, are extracting CO2 from seawater and then turning this into fuel. This part would be very energy intensive and costly. Work on creating fuels from electricity – as opposed to directly from sunlight is massively important. This will ultimately enable solar and wind to produce 100% of our power needs and should be encouraged.
“I will just emphasize that producing electricity from PV is cheap and will get much cheaper over the next decade. Hence, aside from battery storage, we now need to create technologies or industry trends that can either use this power when it’s produced in surplus to offset demand when it is not, or convert this electricity into other useful fuels. We don’t need to float our solar farms.”