Abstract
The purpose of this paper is to clarify the total project costs per kW of onshore wind power facilities in Japan and clarify what factors affect the project unit costs. We collected and organized data on onshore wind power generation facilities in Japan. The coverage of the collected project cost data was 48.9% based on the number of facilities and 55.8% based on capacity. The multiple regression analysis yielded the following main results: i) The larger the single unit capacity, the lower the project unit cost. In other words, larger wind turbines contribute greatly to lower project unit costs; ii) The newer the equipment (the more recently it started operation), the higher the total project unit cost tends to be; and iii) By converting project unit costs into real U.S. dollar prices, we confirmed that project unit costs have been on a downward trend since around 2010 or 2012. However, this decline is largely due to the increase in single unit capacity, i.e., the larger size of wind turbines.
