HOW TO PLAY IT

“If you want to overhaul the electric grid, you need copper,” says Lucas White, natural resources and climate-change portfolio manager at $63 billion (assets) GMO, based in Boston. Solar, wind and electric vehicles all need more of it than fossil-fuel plants: “Copper is the oil of the cleanenergy economy.”

White likes Grupo Mexico, a conglomerate—controlled by billionaire German Larrea Mota Velasco (net worth $27 billion)—that has a 90% stake in Southern Copper,

which has mines in Mexico and the Andes mountains of southeastern Peru. Also attractive is Sandfire Resources Ltd., a western Australia gold-and-copper miner. U.S. investors can buy both stocks over the counter.