Building an artificial island on the sea to produce methanol?

Carbon dioxide is considered to be the biggest cause of global warming. However, humans depend on fossil fuels that emit carbon dioxide, such as oil. The idea of constructing an artificial island in the ocean that can generate methanol that can replace fossil fuels while reducing such carbon dioxide is announced in the American Academy of Sciences Newsletter PNAS draws attention.

This initiative was announced by a research team specializing in material engineering, physics, environmental physics, and marine science at the University of Zurich in Switzerland and the Norwegian University of Science and Technology. The announced initiative is to build a circular artificial island with a diameter of 100m that serves as a factory in the ocean. The artificial island is equipped with solar panels and generates 24,000 kW per hour during the day. The generated electricity is accumulated in the battery and used to produce methanol that proceeds day and night.

Methanol production uses hydrogen produced by electrolyzing seawater and extracting excess carbon dioxide from seawater. First, sodium chloride is removed from seawater, desalted, and an aqueous solution obtained by removing salt is separated into an acidic solution and a basic solution. Then, carbon dioxide is extracted from the acidic aqueous solution. After that, the acidic solution and the basic solution are mixed again, and then the aqueous solution is electrolyzed to recover hydrogen.

The carbon dioxide thus obtained becomes methanol hydrogenated by the catalyst. Since the last process of generating methanol from hydrogen and carbon dioxide is an endothermic reaction, thermal energy is required from the outside, but it is said that the heat generated in the process of generating carbon dioxide and hydrogen can be reused and efficient. Under this initiative, artificial islands can produce 15,300 tons of methanol per year, and the produced methanol is transported to land by transport.

According to the research team’s estimate, about 170,000 artificial islands are needed to use methanol produced on artificial islands instead of fossil fuels used for long-distance transportation around the world. 170,000 may sound enormous, but it is said that 170,000 can be sufficiently dried in the sea area suitable for construction of an artificial island that can secure enough sunlight without waves reaching a height of 2.1m.

According to the research team, since this concept is only a prototype, its feasibility depends on the cost of technology required for the construction of the artificial island, the cost of energy used for transportation, and even the cost of cleaning or maintenance required to maintain the artificial island. The research team says that there is still room for optimization by changing the plan to produce other fuels instead of methanol, so there is a possibility that the plan may change in the future. Related information can be found here .