Water shortages in Southern California made an indelible impression on Evelyn Wang ’00 when she was growing up in Los Angeles. “I was quite young, perhaps in first grade,” she says. “But I remember we weren’t allowed to turn our sprinklers on. And everyone in the neighborhood was given disinfectant tablets for the toilet and…

Concrete already builds our world, and an MIT-invented variant known as electron-­conducting carbon concrete (ec3, pronounced “e c cubed”) holds out the possibility of helping power it, too. Now that vision is one step closer.  Made by combining cement, water, ultra-fine carbon black, and electrolytes, ec3 creates a conductive “nanonetwork” that could enable walls, sidewalks,…