Kennewick saved enough energy to power 175 homes a year by replacing streetlights and lights in city buildings.
Benton PUD officials gave Kennewick a rebate of almost $793,000 on Tuesday, which will help the city pay for the conservation projects completed last year.
Kennewick invested about $2.2 million to replace more than 5,000 streetlights and lights at 20 city buildings with more energy efficient lights, said Steve Plummer, Kennewick's engineering services manager.
A $600,000 federal grant also helped pay for the project, and Plummer said the city expects to see the rest of the cost paid off by energy savings in about seven years.
City hall and the Toyota Center and neighboring arena are among the buildings to benefit from new lights, he said.
"It's really about cost savings, that's what it all comes down to," said Kennewick Mayor Steve Young.
Altogether, the city's efforts saved 3 million kilowatt hours, said Kevin Fischer, Benton PUD's energy efficiency adviser.
The city replaced older technology fluorescent lights called T-12s with the newer T-8 fluorescent lights that put out more light while using less energy, he said.
The difference between the lights is like comparing a computer from the '80s to one from today, Fischer said.
More than 10,000 lamps were replaced in city buildings, Fischer said.
Just replacing city hall's lights saved enough energy to power six homes for a full year, he said.
The new lights in city buildings have about 100,000 hours of life, and should last almost 12 years before needing replacement, Fischer said. Some of the previous lights had to be replaced every two to six months.
Exit signs also were replaced with LED technology, which will save maintenance costs, Fischer said. Streetlights were changed from a high pressure sodium light to the newer induction lights.
Induction is a fluorescent type of light that uses half the energy while providing better quality light, Fischer said.
Instead of a yellow-tinged light, the new streetlights give off more of a white light. The older, yellow-tinged lights had a tendency to cause colors to blend, while colors are easier to distinguish with the induction lighting.
The induction lights also will last longer, adding to the maintenance savings, he said.
Benton PUD General Manager Chad Bartram said conservation projects like the one completed by Kennewick in partnership with the Bonneville Power Administration and Benton PUD help reduce the amount of energy the utility needs and allows the utility to meet conservation targets.
He said he expects conservation efforts will address half of the utility's expected load growth in coming years.