Ever since the traffic light debuted a century ago — it turned 100 years old in August — motorists have been waiting impatiently at red lights. But what if that became a thing of the past? St. Paul inventor Nick Musachio has an idea to keep drivers moving. He calls it the Always Green Traffic Control (AGTC).

It works like this: As a motorist approaches an intersection controlled by a traffic signal, a variable sign tied into the signal’s control box or computer displays the speed that a driver needs to travel to get through the green light. The changing sign, posted a significant distance from the intersection, would allow the driver to adjust to the advertised speed. Thus, motorists would arrive at the intersection without having to stop or get caught up in a queue.

Though it seems to go against the nature of harried commuters to voluntarily lay off the gas, it would take only one motorist to comply with the variable speed sign to make the system work, Musachio said.

That driver would serve as the “pace car,” and those behind would fall in line, allowing more drivers to make a green light and increasing an intersection’s efficiency.

Stopping “is totally unnecessary,” he said as he explained the system to me while we watched car after car pull up to red lights at the intersection at Larpenteur Avenue and Dale Street on the Roseville-St. Paul border.

Musachio is so convinced the technology could revolutionize traffic flow that he secured a patent. He worked with the University of Minnesota Traffic Observatory to create models showing how the system could eliminate the stop-and-go rhythm that red lights create. That would reduce idling and accelerating, which robs motorists of better gas mileage and sends pollutants into the air.

Congestion wastes gas

The U.S. Treasury Department estimates that traffic congestion wastes 1.9 billion gallons of gas and costs American drivers $100 billion a year in lost fuel and time. With more than 311,000 traffic lights in the country, every second sitting at red lights adds up.

The system, at a cost of $40,000 per intersection, could ease frustrations of Green Line light-rail riders, too, said John Hourdos, director of the Minnesota Traffic Observatory. Trains stopping at red lights has been a complaint.

“It can save some time in the order of 5 to 10 seconds per intersection,” he said. “LRT travel times cannot be greatly improved without pre-emption, but you can provide a smoother, less stop-and-go, and maybe a more environmentally friendly trip.”

David Levinson, a transportation expert at the University of Minnesota, says the Always Green Traffic Control has potential.

“I think it would work best for isolated intersections on rural expressways, but there is no reason it couldn’t work in an urban area,” Levinson said. “Static speed signs have been used for decades on Connecticut Avenue in Washington, D.C. Something dynamic should do even better. I do believe it warrants a field test.”

Musachio faces the challenge of getting somebody to do just that. He’s been bending ears of the St. Paul Public Works Department, but so far they have not bitten.

“In theory the system could work, but it has not been tested in a real environment. Until that happens, we won’t consider it,” said city spokeswoman Kari Spreeman.