Houston wants to replace every one of its traffic lights, and the city will soon take bids on the project — where each new bulb costs 20 times more than the old one!

You spend plenty of time stuck at them, but can you tell the difference between one red light and the next?

To a driver it may not mean much, but to the city: “Why we haven’t done this sooner I don’t know,” City Councilman Adrian Garcia said.

The difference between an incandescent traffic light and a high-efficiency LED light is almost too good to believe.

The Department of Energy said the LED lights use 90 percent less electricity than incandescent bulbs. They last six times longer. So starting next month, the city will replace all the old traffic lights in and around downtown with LEDs.

“I think Houston, being the fourth-largest city in the United States, being an energy capital; we need to show that we are serious about our energy consumption,” Garcia said.

But the transition will be expensive. The old bulbs cost $2.50. The LEDs are $46 each.

“Yes they cost more, but they do net savings,” Garcia said. “They do net results.”

Once downtown makes the switch, the rest of Houston’s traffic lights will gradually go green.

Right now taxpayers spend $4 million a year on electricity alone for traffic lights. Factoring in the extra cost for the new lights and that 90 percent energy savings, the city expects to save $3 million dollars a year once it moves to LEDs.

The lights use so little power, in theory, even a solar panel could run some of them. But that’s down the road. For now a red light may not save you any time, but it could already be saving a whole lot more.

To put that $3 million annual savings into perspective, that’s about what the city of Houston spends every year on stamps.

Or as one city councilman put it — that’s enough another police academy class. But in the short term, the energy savings will actually pay for the new lights themselves at all 2,500 intersections across the city by the year 2013.