The winning idea will be nurtured by Cisco and, the company hopes, be turned into a billion-dollar business.

Cisco is being deliberately vague about the details of the winning scheme because it wants to make money off the idea as well as discourage other from trying to exploit it. But a spokesman says the idea calls for making electrical grids more efficient so less energy is wasted, efficiency that could be pushed to homes.

The idea calls for using Cisco infrastructure in the grids to promote the efficiency, the spokesman says.

Here is Cisco's full written description of the winning entry: "The winning team proposed an approach to using the network as the platform for visibility, manageability and, ultimately, optimized control of energy-consuming systems." The winning idea includes "a business plan that improves energy efficiency by taking advantage of Cisco's leadership in Internet Protocol (IP) technology."

The winning team consists of a Russian woman who is a student in Germany, her husband and her brother. Anna Gossen, a computer science student at the Karlsruhe University in Germany, teamed up with her husband, Niels Gossen, a computer science student at the University of Applied Sciences in Germany, and her brother, Sergey Bessonnitsyn, a systems engineer from Russia.