Biomass power generation has been promoted as one of the renewable energy sources in Japan, but most of the fuel, such as wood pellets and palm oil, are imported from overseas. The rapid increase in demand is causing problems such as the clearcutting of valuable natural forests and biodiversity loss. Destroying forests, which have been formed over a long period of time and store large amounts of carbon both above and below ground, will increase the amount of carbon dioxide in the atmosphere.