In Los Angeles, utility companies aren’t solely relying on fossil fuels to feed the city’s hunger for energy. Instead, they are turning to “virtual power plants”: sprawling networks of independent batteries, solar panels, and energy-efficient buildings that are tied together and remotely controlled by software and data systems to collectively reduce customers’ energy demand at peak hours and provide renewable energy supplies in targeted areas. Virtual power plants make economic sense, and could replicated in more cities around the world to use energy wisely.