Oak Harbor city buildings and street lamps are getting new energy efficient lights, an upgrade that is expected to save taxpayers thousands of dollars annually.

Once work is finished, a late night stroll downtown may look a little different too.

The city hired Ameresco, an energy consultant company with offices in Renton, to install new light-emitting diodes at City Hall, the fire station, marina, Public Works, park bathrooms, the windmill at Windjammer Park, police department and senior center.

This project isn’t just about energy savings. Many city buildings use a type of fluorescent light that shortly will no longer be available, said Rich Tyhuis, a city public works operations manager.

Workers also are replacing lights in 253 street lamps. The old high-pressure sodium lights — which produce a yellowish glow — will be replaced with LED fixtures.

The LEDs produce a white light that looks softer from far away but is brighter up close,

“When you stand under them, whatever is underneath brightens up,” Tyhuis said.

“You’ll see people walking underneath better.”

“It’s a different type of light and you’ll notice it.”

Estimated cost of the project is $847,705. A Department of Commerce grant and energy saving incentive money from Puget Sound Energy reduced the city’s bill to $513,644.

Like many “green” projects, the savings come later. Ameresco conducted an analysis of expected energy savings and estimates the payback period for each facility — how long it takes for the energy savings to make up for the upfront costs.

Payback periods range from about three years at the police department to almost 16 years for parks.

The city projects annual energy savings will be about $62,000.

Work is expected to begin later this month and may take several months to complete.