Macquarie’s Green Investment Group (GIG) will sell the shares, but financial details have not been disclosed by either company.
Currently, Acacia Renewables has two offshore wind farms under construction, with a combined capacity of 1.2GW. The wind farms are expected to come online by 2028.
In addition, the company has four wind farms in the pipeline, located across south-west Japan. The locations of the projects were selected to optimise access to Japanese power auctions.
According to the agreement with the GIG, Iberdrola will hold an equal stake in all the six projects alongside GIG. The partners have also agreed to develop GIG’s offshore wind portfolio.
Iberdrola says the acquisition is in line with its strategy to establish itself in the early development stage of Japan’s offshore wind market, which is estimated to have strong growth potential.
Both GIG and Iberdrola have agreed to strengthen their partnership in the country while including Japanese companies in the projects.
At present, Japan has approximately 70MW of installed offshore wind capacity. However, the country hopes to further decarbonise its energy mix and promote energy independence.
Forecasts suggest that the market will reach 10GW installed in 2030, and up to 37GW in 2050.
In May, Iberdrola Renovables France acquired French renewable energy company Aalto Power for $107m (€100m).
Owned by Aiolos and Caisse des Dépôts et Consignations, Aalto Power is based in Marseille and was established in 2005.