Future robo-taxis could charge themselves and help balance the electric grid

Electric robo-taxis are a real possibility. Trends in transportation, energy, and demographics indicate that future vehicles will operate autonomously, run on electricity rather than fossil fuels, and be shared instead of privately owned. But before everyone can carpool in self-driving electric cars, we need places to charge them. Today, that's a challenge: there are only about 20,000 charging stations for electric vehicles in the US. McKinsey predicts that major economies (China, Europe, India, and the US) will need to invest $55 billion in charging infrastructure by 2031 to support the 140 million electric vehicles that will be on the road then.