The U.S. uses about 500 gigawatts of power at any moment. Is it possible to cover that whole demand with emissions-free power sources? Well, nuclear, which has virtually no greenhouse gas emissions, could account for about 20 percent; the rest would have to be renewables. And renewables are intermittent, so they'd have to be backed up by about 80 gigawatts worth of batteries, says Davide Castelvecchi at Scientific American.
Get Grist in Your Inbox
Christopher Mims's dystopian non-fiction is sought after by an ever-growing roster of publications.