A model for how Japan may evolve as it relies more on renewables can be found in the southwestern region of Kyushu. The area has seen renewables capacity expand at over 30% a year. Yet the quick growth has also created a major challenge: excess electricity at certain times of the day is currently wasted.

Due to the intermittent nature of solar and wind energy, local grids are keen to retain traditional energy sources. At times of surplus, some power plants are asked to cut output. To date, solar has been the most frequently curtailed renewable source.
What’s more, Kyushu’s conundrum will soon spread to four more regions of Japan, according to government forecasts. Whether local grids curtail output from solar farms or other power sources, someone will be hit with financial losses. Both operators of renewables assets and older utilities that run thermal and nuclear plants are warning that curtailing their output would discourage future investments.

The ability to resolve the situation in Kyushu will prove vital in creating a roadmap that the rest of the country can deploy.