(Carol M. Highsmith)

Interior Secretary Ken Salazar and Energy Secretary Steven Chu plan to flip the switch Monday night on newly installed LED lights that will illuminate most of the Mall — and reduce the National Park Service’s energy bill.

The energy-efficient lights, donated by bulb maker Osram Sylvania and installed for free by Pepco, should cut the energy usage of the bulbs by 60 to 65 percent, Interior Department officials said. With a long stretch of walking and bike paths and dozens of structures accessible to the public at all hours of the day, the Mall consumes the most electricity of the 397 national parks.

LEDs provide brighter lighting and last longer, so much so that the Park Service expects to not have to replace the bulbs for up to 25 years.

Using the bulbs to light the nation’s most high-profile national park might earn bulb manufacturers — and Pepco — some goodwill.

The Energy Independence Act of 2007 requires light-bulb manufacturers to begin phasing out less-efficient bulbs this month. Retailers must stop selling less efficient 100-watt incandescent bulbs on Tuesday, while less efficient 75- , 60- and 40-watt bulbs must be phased out by Jan. 2014. Retailers can still sell off what light bulbs are in stock or in their supply chain and manufacturers are producing more efficient 100-watt incandescent bulbs filled with halogen gas.

The new federal bulb standards anger conservatives, who consider the changes another example of government interference. The federal spending bill that passed in December provided no funding for the Energy Department to enforce the changes, but the new rule changes will still take effect as scheduled.

And having Pepco personnel install the bulbs for free might earn the company some love from Washington area customers long frustrated with years of missteps by the company, especially in the aftermath of major winter storms.

Follow Ed O’Keefe on Twitter: @edatpost

Editor’s Note: A previous version of this report incorrectly stated some stipulations of the Energy Independence Act.

Further reading:

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President Obama cracks jokes at elite Alfalfa Club dinner

Comparing Obama and Reagan’s economic records

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