Most Americans use electricity, gas or oil to heat and cool their homes. But the small city of Brainerd, Minn., is turning to something a bit less conventional: the sewer.
As it turns out, a sewer — the place where a city's hot showers, dishwashing water and organic matter end up — is a pretty warm place. That heat can generate energy — meaning a city's sewer system can hold tremendous potential for heating and cooling.
It's just that unexpected energy source that Brainerd hopes to exploit.
This week, President Obama signed a law banning synthetic marijuana and other synthetic drugs. Dozens of states and local governments have already tried to outlaw fake marijuana, which has been blamed for hundreds of emergency room visits and a handful of fatalities.
But the bans have proved largely ineffective, and there are fears that the federal law won't be any different.
Synthetic marijuana looks a bit like dried grass clippings. It's readily available on the Internet and in convenience stores and smoke shops, where it's sold as herbal incense or potpourri.