Solar and wind energy could power your traffic lights

Here's one way of making sure the traffic light is always "green": a team of researchers at the University of Nebraska-Lincoln is working on a three-year green energy project that would use wind and solar energy to power street and traffic lights, while integrating excess electricity into the municipal power grid.

Last year, a small wind generator was installed at an intersection in Nebraska (solar panels will be added this spring), and three more are expected to be placed at a later stage.

Funded by a $1 million grant from the U.S. Department of Transportation, the Energy Plus Roadways project hopes to generate more renewable energy than the city’s infrastructure can consume, and then sell the rest back to power companies.

Currently Lincoln Nebraska spends almost $1 million to run its streetlights and $72,000 to run traffic signals and signs. If all 300,000 roadway intersections in the U.S. that have traffic signals used this system, nearly $50 million would be saved each year, according to University of Nebraska-Lincoln researchers. Beyond just eliminating operating costs, the system will also cut air pollution and create green-collar jobs.

Since the traffic lights are connected to the grid, in case of shady or non-windy days, back-up electricity will always exist.

According to Government Technology, a second phase of the project, scheduled to begin in May, involves "developing the electronic control system that would allow a network of wind and solar power generators to intelligently distribute electricity where it’s needed."

Essentially, turbines from still or shady areas can use the control system and "borrow" power from another generator that's producing excess energy. Existing power lines will be used to transmit the power from one area of the grid to another -- so additional costs will not be incurred.

The system is even designed to cut against all loses. Government Technology adds, "Each power station will be able to transition between three operating modes. In one operating mode, the power station will rely entirely on power from the main grid. This might occur when it’s cloudy or not windy for an extended period. The second operating mode will allow a station to draw power exclusively from solar and wind power on the grid. The third mode allows a working generator to isolate itself from the rest of the grid in case of a problem nearby, minimizing the scope of the problem."

Costs are a little less than $20,000 right now, though researchers are hoping to push the price points down eventually.

As the price of fossil fuel continues to rise and green technology becomes more viable, the advantages of a system like this become clear. The initial investment would eventually save cities tremendous money on power, reduce pollution and cut our over dependence on nonrenewable energy.

This post was originally published on Smartplanet.com