A few things you might not know about holiday lights

Find out what they're costing you, too, with this calculator

Lights are strung everywhere in December: lining the streets, buildings, and your house inside and out. As we ooh and ahh at the year's most festive decorations, here are a few fun facts about lights:

1. After inventing the light bulb in 1879, Thomas Edison debuted the first string of Christmas lights at his Menlo Park Laboratory in 1880. The electrified strands wowed railroad passengers, and two years later, his friend and business partner Edward H. Johnson lit up the first Christmas tree with bulbs instead of candles.

2. Twinkling lights and your thermometer have a lot in common. Like a thermometer, the red-tipped light on your tree contains a bimetallic strip. When the strip heats up, the metal bends – momentarily breaking the circuit and causing the light to turn off. As the metal cools, it bends back to its original position, and the light comes back.

3. Shortly after a GE engineer invented the red LED, Rudolph secured his place as a holiday symbol during a 1964 General Electric Fantasy Hour broadcast. The company was still trying to convince the public of the value of artificial light, and who better to do that than Rudolph and his now-signature red nose?

4. In the early 1900s, wealthy families were able to hire electricians to illuminate their Christmas tree for about $300 ($2,000 in today’s dollars.) Luckily, decorating is much more affordable today. According to Christmas Lights Etc., a typical household will spend about $10.78 a month using incandescent bulbs and $1.63 using LEDs to decorate for the holidays.

Ever wonder what your holiday decorations cost?

Find out with this calculator from Duke Energy and discover ways to make your display more efficient.