Mentawai Off-Grid Biomass Power Plant Project PT Charta Putra Indonesia, known as Clean Power Indonesia (CPI) proposes to develop, implement and operate an Off-Grid Bamboo-Based Biomass Power Plant Project with a total combined generating capacity of 5 MW. The Project will entail constructing a power plant in each of the 20 villages located in Siberut Island of the Mentawai Islands, West Sumatera Province, Indonesia.