Although Japanese companies have offshore wind assets in countries from Taiwan to Belgium and Britain, they have yet to build large-scale farms at home.

Japan plans to announce by the end of March the winners of a second major round of offshore wind tenders to build 1.8 gigawatt (GW) of capacity in four areas.

HOW DOES JAPAN PLAN TO BOOST CAPACITY?

Japan's 136 megawatt (MW) of offshore wind capacity installed by 2022 was a fraction of Britain's nearly 14 GW and China's 31 GW, the Global Wind Energy Council says.

It aims to have 10 GW by 2030, with up to 45 GW operational by 2040, as it targets a share of 36% to 38% for renewables in its electricity mix by the end of this decade, compared to about 20% now, in its race to be carbon neutral by 2050.

A Marubeni-led consortium launched Japan's first large-scale commercial offshore wind operations at Noshiro port (84 MW) and Akita port (55 MW) in late 2022 and early 2023.

Danish wind turbine maker Vestas provided bottom-fixed turbines for Marubeni's farms.

WHAT WAS THE RESULT OF THE FIRST ROUND?

A Mitsubishi-led consortium won all three offshore wind farm auctions in 2021 in the regions of Akita and Chiba, with combined capacity of 1.7 GW and a target start-up date of 2028 to 2030.

All will have bottom-fixed structures. General Electric will make 134 wind turbines, each of capacity 13 MW, to be assembled and maintained by Japan's Toshiba.

The first round spurred interest by foreign companies in entering the Japanese market, among them Denmark's Orsted, Germany's RWE and Norway's Equinor.

WHAT HAPPENS IN THE SECOND ROUND?

The government wrapped up its six-month auction for another 1.8 GW of capacity in four areas on June 30, with winners set to be announced by the end of March 2024, or even as soon as December.

The revised rules bar companies from revealing intent to bid.

For the second round, the ministry of economy, trade and industry (METI) set a bid price cap of 19 yen per kilowatt hour (kWh), below the first round figure of 29 yen, except for Enoshima, where construction challenges kept the ceiling at 29 yen.

JERA, Japan's top power generator, said it was running environmental assessments of the Oga-Katagami-Akita project and the Happo-Noshiro project.

Other companies making assessments - an indication of a bid - included Mitsui & Co, Osaka Gas, TEPCO Renewable Power, Itochu Corp, Tokyo Gas, Marubeni and some foreigners, environmental ministry documents show.

The government is gathering public opinion until Dec. 17 for a third round of auctions to offer 1.05 GW on two offshore wind farms.

WHAT ARE THE PLANS FOR FLOATING OFFSHORE PLANTS?

In 2021, the government selected a consortium of six companies led by Toda Corp to build the 16.8 MW Goto floating offshore wind farm in Nagasaki prefecture. It was the only auction bidder for the small project.

In September, Toda and its partners flagged a two-year delay in startup of the Goto project, to January 2026, because of defects in a floating structure.

Japan is preparing a new roadmap for floating offshore wind power by the end of March 2024.

WHAT CONSTRAINTS AWAIT?

METI recommends a domestic share of 60% of the supply chain by 2040. All major global renewable energy companies, from Orsted and RWE to BP, Equinor and Iberdrola, have set up offices in Japan.

GE Renewable Energy has teamed with Toshiba Energy Systems & Solutions to make GE's Haliade-X offshore wind turbines near Tokyo from 2026, turning out about 80 units a year, or 1 GW annually.

The partnership is the sole nacelle supplier for the first round.

(Reporting by Katya Golubkova and Yuka Obayashi; Editing by Clarence Fernandez)