The worst thing about your next flight won’t be getting stuck in the middle seat; it’s the carbon emissions your kerosene-guzzling jet will be producing. Aviation currently accounts for about 1 percent of carbon emissions in the world, but over the next 50 years—with China and India getting into the global-tourism game—flying will jump to 4 percent or more, and further contribute to ozone depletion and noise pollution. The solution for now? Try to keep your flights to a minimum.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.