The International Energy Agency (iea) reckons the world will add as much renewable power in the coming five years as it did in the past 20. Britain, France and Norway, among others, plan to ban the sale of new internal-combustion cars. Even where bans are not on the statute books, electric-car sales are growing rapidly. Power grids are changing too, as wind turbines and solar panels displace fossil-fuelled power plants. The big economies are embarking on a grand electrification project. Demand for the minerals batteries, and lots of them both to propel the cars and to store energy from intermittent renewable power stations are made is soaring. Will the mining interfere with aquatic life ?