FEARGUS O'SULLIVAN for CityLab:  Just outside the Welsh city of Swansea, the U.K. is planning one of the most innovative power plants ever constructed. It’s not the plant’s size that is striking, though it could ultimately provide power to 155,000 homes for 120 years. It’s the source of its power that breaks ground: tides channeled into an artificially constructed lagoon.

Granted full planning permission this June, the Swansea Bay Tidal Lagoon will be the world’s first ever plant to generate electricity using this method. Should it prove successful, the plant’s template could be adopted worldwide as a way of generating green power while simultaneously providing sea wall protection to coastal communities.  Cont'd...