this article was originally published here: http://www.eia.doe.gov/kids/news_holiday_lights.cfm

Holiday lights add cheer and festivity to holiday celebrations (Christmas, Hanukkah, Kwanzaa, etc.) Lights are easy to set up and beautiful to look at, either inside or outside the home. Yet, how many of us consider the electricity use and cost of these lights? Depending on the type and number of lights that you use and how long you keep them on, the cost of using holiday lights can range from less than one to many dollars over the holiday. Using electricity also results in emissions of carbon dioxide (CO2) and pollutants that have a negative impact on the environment. Here are a few tips that will help you save electricity and money during the holidays:

• The type of lights you choose is very important! In general, larger bulbs use more electricity than smaller bulbs, and incandescent bulbs use more than Light Emitting Diode (LED) lights. The largest holiday incandescent bulbs use between 4 and 10 watts per bulb, and incandescent mini-light bulbs use about one-tenth as much.  LED lights use the least amount – 0.1 to 0.04 watts per bulb!  While LED lights cost the most to buy, they have other advantages besides high efficiency and lower operating costs that can make their higher prices worth it.  LED bulbs can last 50 times longer than incandescent bulbs, and they don’t get hot.  You can connect many more strings of LED lights together than incandescent strings without overloading a typical household circuit.  And if a bulb on a string of LED lights does go out, the rest of the lights in the string will still work.  So there’s no searching for that one bad bulb keeping the rest of the string from operating!
• More lights require more energy. It only makes sense that your electricity use will go up as you add larger and more strings of lights. Keep in mind that not all lights and light strings are the same. The large (C-7 and C-9) holiday light bulbs come in strings of 25 to 30, while mini-lights may have 35 to 200 bulbs per string. LED lights may have 25 to 100 lights per string.  Icicle style light strings use mini-lights (incandescent or LED), but because of their shape, usually require many more strings to cover the same distance as a string of regular mini-lights.
• The longer your lights are on, the more energy they use. It doesn’t take a rocket scientist to figure out that leaving lights on all night (maybe 12 hours) will use 3 times as much electricity having them on for only 4 hours at night. Using a timer for lights is a great way to control when your lights go on and off so you don’t have to remember to do it!