LEWISTON — A money-saving streetlight timer could mean darker dusks and dawns downtown for the next 90 days.

The city is testing a streetlight controller designed to reduce the amount of time streetlights are lit.

Instead of a light sensor that turns on streetlights as soon as the sun sets, the new timer relies on a calendar and a clock. Streetlights will go on 45 minutes after sunset and turn off 45 minutes before sunrise.

“It turns the lights on closer to real darkness, when they’re really needed,” said Ian Houseal, the city’s energy czar. “The lights are not really helping if they go on at sunset, before it really is dark.”

The controller is designed by Massachusetts-based Consurv Technologies.

The device should save the city about $3,800 over the next three months, Houseal said.

“This all started last spring when councilors requested something like this, but it wasn’t available at the time,” Houseal said. “We were contacted by a company that said they were testing this controller, and would we be willing to try it.”

The single controller, a $150 switch, controls all of the streetlights downtown. Streetlights outside the downtown have individual light sensors that turn them on and off.

“It’s too difficult to change them now,” Houseal said.

The new controller was turned on Oct. 23, and should be in place until late January, he said.

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