Japan identified offshore wind power as one of the core sectors to help cut the nation’s reliance on fossil fuels. As the nation starts to build the offshore wind sector almost from scratch, however, a number of technical challenges have become apparent. One is the knowledge and experience gap in power transmission systems.

Simply put, Japan needs to accelerate R&D in technologies such as power cables. The kind of cables used locally to date are different to the lines that will be required to connect the 45 GW in offshore wind power projects the government envisions in the waters by 2040.

First, however, the government must determine which transmission infrastructure will need to be built or strengthened. After suffering setbacks in the past in developing domestic wind turbines, Japan is keen to avoid the same in technology that will deliver the electricity to consumers.

One type of grid technology gaining attention, and already receiving financing, is long-distance direct current (DC) transmission via undersea cable.