Add the hallowed halls of Congress to places where Cree's LED lights are being installed.

Or at least the cafeteria in Washington's Rayburn House Office Building. Think of it as illuminating a dining hall of power using less power.

U.S. Sen. Kay Hagan, a North Carolina Democrat, took partial credit for the news. In a news release from her office, Hagan wrote that she sent a letter last fall to the Senate Rules Committee encouraging them to select Cree's LEDs for new, energy-efficient lighting.

The light-emitting diodes made by Durham-based Cree are being adopted by cities, schools and businesses eager to embrace LEDs, which cost more than traditional lights but last much longer and use much less electricity.

But shares took a hit Wednesday after Cree reported earnings that didn't exceed optimistic estimates on Wall Street. Also, Cree plans to increase spending on research, which could erode profit.

Cree's shares fell $5.95 to close at $76.22 Wednesday.