The city on Tuesday received a $1.9 million rebate check from the ratepayer­-funded Hawai’i Energy program for converting more than 53,000 city streetlights across Oahu to more energy-­efficient light emitting diode (LED) technology.

The $46.6 million public­-private project was financed through partner Johnson Controls, and the city did not spend any money upfront in completing its two-year project. The company will be paid back from the projected $5 million in savings the city is expected to accrue through the conversion.

The rebate check received Tuesday also will go toward paying Johnson Controls back. Hawai’i Energy is a ratepayer-funded conservation and efficiency program administered by Leidos Engineering LLC under a contract with the state Public Utilities Commission to promote and educate people and businesses about energy efficiency and conservation. Among the ways it does that is through rebates for those who practice energy efficiency.

“Most people don’t realize that energy efficiency can get us half-way to the (carbon dioxide) reductions that we need to achieve to reach our climate goals, and this project will reduce 300,000 tons of CO2 over the life of the streetlights,” said Brian Kealoha, Hawai’i Energy’s executive director.

Mayor Kirk Caldwell said the LED lights also make streets brighter than the conventional lamps they replaced. “I think it’s obvious to most people that a brighter street is a safer street for pedestrians who may be crossing, for people who may be driving down the street, and also to cut down on crime,” Caldwell said.

LED lights are also more “directed” to the street so seabirds and other wildlife won’t be disturbed or become disoriented by seeing them, Caldwell said.

About 99.9 percent of the lamps under the city’s control have converted, leaving about 70 lights in older neighborhoods where jurisdiction is uncertain, he said.

An undetermined number of streetlights in newer subdivisions not under city ownership were not replaced. They include the Villages of Kapolei, which is owned by the state and portions of the Ewa By Gentry project. They will be converted when the city takes ownership of them.

“We’re trying our darndest to become a more resilient community,” Caldwell said.

City Councilman Brandon Elefante said he hopes the city administration will come up with a plan to convert the lights at city parks to LED technology, as well.

Broder McMurtry, Johnson Controls business development manager, said studies have shown that drivers have a quicker reaction time when lights are brighter. Another advantage of LEDs is they last much longer than conventional lights.

Allyn Lee, program administrator for the city Department of Design and Construction’s Mechanical and Electrical Division, said the new lights have a lifespan of 100,000-150,000 hours. Lights are typically on about 4,000 hours each year “so these lights can last 20 to 30 years.”

The old lights would last an average of about 10,000 hours, Lee said. Longer-lasting lights mean additional savings in both replacement lights and personnel hours to switch them out, he said.

The LED conversion drew complaints from the Sierra Club Oahu chapter and local astronomers and other scientists who said the LEDs installed by the city are “bluer” and have a more harmful impact than more technologically advanced versions now on the market.

They urged the city to use 2700 kelvin color temperature LEDs, instead of the 4000K and 3000K bulbs used in the project. Kelvin is the term used to express “color temperature” with the higher kelvin emitting a “cooler” or more bluish-white light.

Lee said city officials met with the scientists several times about using the lower kelvin LEDs.

“When we analyzed the light output, did illumination calculations with the 2700 at that time, it didn’t meet the minimum requirements (for brightness of city street lights),” Lee said. “So therefore we stuck with the 3000K LED lights.

Lee said only about 10 percent of the lights converted, primarily those on major arterial streets around the island, used 4000K bulbs while the rest used 3000K.