[COUGH! COUGH!] What were we talking about? Oh right, right, right. Marijuana's continued prohibition in 48 mellow-harshing states has an unintended side effect (besides making Phish unlistenable): It narfs $6 billion in energy costs and pumps out as much greenhouse gas as 3 million cars. Scientists from the Lawrence Berkeley National Laboratory found that the marijuana industry is responsible for about 1 percent of all U.S. electricity usage.
The reason is simple. To evade detection, growers work indoors -- where lights, ventilation, temperature controls, and presumably industrial-grade lava lamps suck up a lot of juice. From ThinkProgress: