led streetlight

The Minnesota Department of Transportation (MnDOT) in the US will be replacing more than 28,500 roadway lights in the state with LED lights in the next four years.

The scope of the project includes the replacement of existing high-pressure sodium lights to better quality LED or light-emitting diode technology.

The lighting conversion project along roads and bridges across the state will ensure improved road safety and financial savings of up to $1.45m in energy costs.

The state can save an extra $500,000 every year in maintenance and replacement costs for the light fixtures and bulbs, which will be replaced by LED lights.

MnDOT Twin Cities Metro area signal design and lighting management engineer Michael Gerbensky said: "Drivers will see whiter light, but the biggest impact will be a large reduction in the energy bill and eliminating the cost of bulb replacement every four years.

"This means having our maintenance personnel out on the roadway less often, which reduces traffic control costs and it means improved safety. That savings can go to preserving our roadways."

"The biggest impact will be a large reduction in the energy bill and eliminating the cost of bulb replacement every four years."

Expected to be completed by 2020, nearly 10,000 of the 28,500 new LED roadway lights will be installed in the Greater Minnesota region while the remaining will be used to light the Twin Cities Metro area.

The installation in the Twin Cities is slated to be completed by the end of the year, whereas deployment in Greater Minnesota will take longer time due to its large geographical area.

According to MnDOT, the new LED lights will last about 100,000h, which is equivalent to an average of 18 years compared with the four-year life span of the existing lights.

In 2010, Minneapolis and Hennepin County conducted bulb testing that revealed LED lights emanates less heat and use nearly half the power needed for similar light levels.

Image: LED streetlights. Photo: courtesy of Cgwalther via Wikipedia.