Wind energy activities in Japan have been increasing since 1999, with a focus on developing suitable wind turbine generator systems for the country's conditions. By the end of 1999, Japan had a cumulative wind power capacity of 75 MW, with plans to reach 100 MW soon. A 20 MW wind farm was completed in December 1999, and another 30 MW farm is under construction. Despite excluding mountainous and offshore areas, Japan's wind potential is estimated to be at least 1,440 MW, with the possibility of capturing even more wind energy. The main challenge to address is the grid problem.