Could four wind turbines generate enough energy to power an entire city? In Rock Port, Missouri, the answer is yes.

With just 1,300 people, Rock Port doesn't use a whole lot of energy - but most of what it does use, it gets from wind. In fact, Rock Port's four turbines can generate almost 25 percent more electricity than the town needs, so Rock Port sells that surplus to neighboring towns.

The source of all this power is nearby Loess Hills Wind Farm. Loess Hills was built by a partnership of John Deere Capital and the Wind Capital Group, which has similar projects in 16 states. According to the project manager, construction of the farms employed several hundred.

So would wind power work in a city bigger than 1,300? Yes, though the US doesn't have a wind farm big enough to power a major city just yet. Even so, many projects have been built and more are going up. That helps power cities of all sizes, taking the edge off the rising costs of electricity.