140,000 traffic signals to change to LED bulbs

LEDs consume 85 percent less electricity than traditional bulbs, and the California Energy Commission says swapping all the state's traffic signals would save 70 megawatts of electricity -- enough to power 70,000 homes.

The goal of the current switch is to save 6 megawatts by June 1, to help stave off hours of rolling blackouts expected this summer unless the state reduces its power use or more power plants get up and running.

Claudia Chander, spokeswoman with the California Energy Commission, said the lights are brighter, and therefore easier to see in the rain and fog. Each traffic signal is composed of dozens of diodes, each about the size of a miniature Christmas light.

LED bulbs last seven years versus one year, but are considerably more expensive than their traditional brethren. Labor and bulb costs for switching to LEDs costs $3.34 million per megawatt.

But over time, LEDs pay off. A single incandescent traffic signal for seven years costs $430.32 (based on 11 cents per kilowatt hour of electricity). Electricity for an LED is $51.92 over the same time span, according to the Consortium for Energy Efficiency. And since they burn out less frequently, they cost less to maintain.

The commission and the investor-owned utilities are helping fund the current effort to replace the signals. The Energy Commission has $10 million for the project and is paying half the cost for 43 cities, counties and state agencies to change their light bulbs, said Virginia Lew, energy specialist with the commission. Lew said a bill is before the Legislature that would provide an additional $14.5 million for LED traffic lights.

Caltrans wants to convert all 210,000 lights on the 15,000 miles of state, interstate and U.S. Highways it oversees. That would save $5.5 million a year on energy bills, said Gonzalo Gomez, senior electrical engineer for maintenance with Caltrans. So far, the agency has switched about 50,000 red lights since it began in 1996.

But the California Finance Department last month rejected a Caltrans request for $25 million from the state's $1 billion emergency energy conservation fund to pay for future signals.<