Seattle plans to spend an estimated $23 million to upgrade 40,000 of it 84 streetlights over by replacing their high-pressure sodium lights with state-of-the-art light-emitting diodes (LEDs). It's a big up-front investment, one that city officials say will eventually be paid back because the LEDs use half the energy and last three times as long.

"It's part of our plan to invest in lights that will eventually save us money."said City councilman Bruce Harrell, chairman of the council's Energy, Technology and Civil Rights Committee."They will eventually pay for themselves."

Currently it costs the city more than $13 million annually in electricity use and maintenance to operate its street lights using the sodium lights, and officials say the light isn't the greastest.

The city began testing LEDs three years ago as a pilot project, first near City Light's North Service Centre and then on Capitol Hill and in West Seattle and South Part neighborhoods.