Some of the world’s largest banks and construction firms gathered with seven African governments Monday to chat about plans for an $80 billion hydroelectric dam on the Congo River. The proposed Grand Inga dam could generate twice the electricity of China’s controversial Three Gorges Dam and greatly increase the amount of cheap and clean power currently available in Africa, according to supporters. “It is the greatest sustainable development project, offering Africa a unique chance for interdependence and prosperity,” says Gerald Doucet of the World Energy Council. But critics say electricity generated by the dam would be exported to urban centers as far away as Europe and Israel, while rural, poor areas in the Congo and surrounding countries see none of the benefit. Backers of the dam say they’ll be mindful of the social and environmental implications of the project. If Grand Inga gets the green light, it could be operating by 2022.