Japan launches first osmotic power plant in Fukuoka

Japan has commissioned its first osmotic power facility in Fukuoka, making it only the second operational plant of its kind globally, reported The Guardian.

The project is expected to generate around 880,000 kilowatt hours of electricity each year, enough to partly power a desalination plant supplying water to the city and nearby areas. According to Dr Ali Altaee of the University of Technology Sydney, the output is equivalent to the electricity use of about 220 households in Japan.

Unlike wind or solar, osmotic power can run continuously, as it depends on the mixing of fresh and salt water rather than weather conditions. The Fukuoka plant places freshwater or treated wastewater on one side of a membrane and seawater on the other. As water moves toward the saltier side, pressure builds and drives a turbine connected to a generator. The facility uses concentrated seawater left over from desalination, which increases efficiency.

The world’s first commercial-scale osmotic plant was developed in 2023 in Mariager, Denmark, by SaltPower.  

Experts say scaling up remains a challenge. Energy losses occur in pumping and as water passes through membranes. However, advances in technology are improving performance.