Wind turbine without propellers tries to protect birds from collisions; System tested in a factory in Hokkaido

KUSHIRO, Hokkaido – A ‘propellerless’ wind turbine is being tested as part of efforts to prevent bird strikes at wind power generators.

The Ministry of Environment has set up a smaller version of the wind turbine at its wild bird rehabilitation center in Kushiro, Hokkaido. The ministry, which is conducting the trial in collaboration with the Institute for Raptor Biomedicine Japan, is monitoring how birds respond to the equipment to identify challenges in using the turbine in a natural environment.

According to the ministry, about 80 birds have died since 2000 after flying into wind power generators, including sea eagles and Steller’s sea eagles, both designated as national wildlife treasures. The number of birds killed could be even higher if offshore facilities are taken into account. The high speed of the propellers on the generators made them difficult to see, causing birds to collide with them.

The test began in early December and is being conducted at the ministry’s Kushiro-Shitsugen Wildlife Center, located near the city’s large swamp area. The new generator, known as the Magnus Vertical Axis Wind Turbine, was developed by Tokyo-based startup Challenergy Inc. Two cylinders are located on opposite sides of a central axis and electricity is generated as they rotate around the axis. Because the cylinders rotate more slowly than regular wind generators, it is believed that the Magnus turbine would reduce the number of bird strikes.

The smaller version, which is 2.6 meters high – about an eighth of the size of the large turbine – operates from dawn to dusk in a cage that currently shelters several sea eagles and other birds. The birds will be monitored and the results of the tests will be made public at the end of March, according to the ministry.

Keisuke Saito, head of the Birds of Prey Institute, said raptor species could likely keep an eye on the cylinders as they rotate slowly. “The Magnus turbine has the potential to both prevent bird strikes and generate renewable energy,” he added.

Lower impact on the environment

According to Atsushi Shimizu, CEO of Challenergy, the blade tips of propeller-type wind turbines spin at speeds of more than 200 km/h, making it difficult for birds to see and avoid them. In contrast, the Magnus turbine’s cylinders rotate at only one-eighth to one-tenth the speed of the propellers. In addition, the Magnus is much quieter, with a noise level comparable to that of a fan or the outdoor unit of an air conditioner.

The Magnus is currently being operated on a trial basis in the Philippines and Ishigaki Island, Okinawa Prefecture. In the Philippines, a turbine has been installed near a lighthouse that is 20 meters high and can generate 10 kilowatts. The electricity generated by the turbine is used to illuminate the lighthouse, which is popular as a tourist spot.

“This is the world’s first attempt to commercially use the Magnus turbine, which aims to live in harmony with nature,” said Shimizu. “Although we face challenges to expand energy generation capacity, we will continue to make further efforts.”