関連ワード:  is biomass a green energy source    is biomass a renewable energy source    biomass is a renewable energy source give reason    is biomass a non renewable energy source    is biomass considered a renewable energy source    is biomass/biofuels a renewable energy source    is biomass a renewable or nonrenewable energy source    biomass is a non renewable energy source...true or false    is biomass an alternative energy source    biomass is renewable energy source or not