Business Consortium to Develop Green Energy Base Featuring Floating Wind Turbines, Ammonia Plants

The Yomiuri Shimbun
Facility integrated with offshore floating wind farm, ammonia production plant

TOMAKOMAI, Hokkaido — A consortium of companies led by a major concrete manufacturer in Tomakomai, Hokkaido, plans to develop a renewable energy base, featuring floating wind turbines and ammonia production plants.

Ammonia has received a great deal of attention in recent years as a decarbonization fuel.

More than 50 leading domestic companies, including trading, shipping, construction, energy and other firms, will form a consortium in April. They aim to complete construction of the first floating “plantship” in 2028.

Each plantship will be an equilateral triangle 70 meters long and 40 meters high. They will be equipped with concrete floats at each corner, a 120-meter-high wind turbine with a 10,000-kilowatt output, and an ammonia production plant.

In the future, the companies hope to spread the green energy project over a wide area of the ocean, including in Japan’s exclusive economic zone (EEZ).

The company spearheading the project is Aizawa Concrete Corp. of Tomakomai. The company is known for being the first in Japan to commercialize self-healing concrete, which uses bacteria to naturally repair cracks.

Under the plan, electricity generated by floating wind turbines will be used to electrolyze seawater and extract hydrogen. The hydrogen will then be reacted with nitrogen to produce ammonia.

The consortium plans to have 10 plantships per sea area and to transport the ammonia produced by ship.

The Yomiuri Shimbun
Aizawa Concrete Corp.’s booth at Smart Energy Week March 2024, in Tokyo in February

4 candidate sites

Offshore wind power has been identified as a key renewable energy source in the government’s “Basic Plan on Ocean Policy.” However, wind turbines fixed to the seabed, the most common type of offshore power, can only be installed in shallow waters.

The Economy, Trade and Industry Ministry, which plans to conduct tests for floating wind turbines, has currently selected four sea areas around Japan, including around Hokkaido, as candidate sites.

The government has also submitted a bill to the Diet to amend the law to allow deployment of floating wind turbines in the EEZ.

Ammonia produced from renewable hydrogen is called green ammonia because no carbon dioxide is emitted in the production process.

Unlike hydrogen, green ammonia has a wide range of applications as there is technology for transporting the compound safely and simply. Once delivered, ammonia can then be broken down into hydrogen.

In the “Green Growth Strategy” compiled by the ministry in 2020, “ammonia fuel” is listed as one of the 14 key industrial fields.

Mass producing ammonia

Some major electric power companies are also aiming to reduce their use of coal by conducting tests for “mixed-burning.” This involves mixing ammonia with coal for thermal power generation.

“There are hundreds of ports across the country where plantships can be built,” said Yoshihiro Aizawa, president of Aizawa Concrete. “If the construction technology is established and concrete companies from all over the country cooperate, mass production of ammonia will be possible.”