It takes only 48 hours to distill a barrel of whiskey. The next decade is spent making it taste good. The liquor undergoes constant chemical changes, some from the charred oak of the barrel itself, which acts like a sieve, trapping the large-molecule forms of alcohol (methanol, butanol) that give young whiskey such a rough edge. The process takes years, and as a result good whiskey is old and expensive.
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.