I’ve written a fair amount in the past about LED Christmas lights and the environmental benefits and costs savings they can provide.  But one thing I don’t think I’ve discussed is the power consumption differences of various types of incandescent Christmas lights.  Because some of the older style C7 and C9 Christmas lights draw as much as 7 watts of electricity per bulb, upgrading your old style incandescent lights to LED first will likely have the biggest payoff.  I do not want to infere or suggest that small changes don’t make a big impact but sometimes it makes economic sense to prioritize certain lighting upgrades over others.

Let’s use a simple example to illustrate this point.  A average size two store home that is decorated with 1000 C9 incandescent Christmas lights which are illuminated for 8 hours a day will consume about 40 KWh of electricity each day.  The total cost of operating these lights for a 30 day period would be about $115.00.  The same set up using a C7 LED replacement bulb would only consume about .48 KWh of electricity each day for a 30 day cost of only $1.37.  That is a total savings of over $100 in less than a month.

While someone using 1000 incandescent mini lights for the same amount of time during the holiday season would save a lot of energy and money by switching to LED Christmas lights, the savings are not nearly as substantial as in the example above.  The 1000 mini lights would consume about 120 KWh of power during the 30 day period while the LEDs would consume less than 15.  This is still 80% less power and money but as you can see the financial impact as not nearly as great as in the first example.

In the long run switching over to LEDs will make a big difference in holiday energy consumption no matter what type of incandescent lights you are replacing; however, if you have both C7 or C9 and mini lights and you can’t upgrade all of them at once it makes a lot of sense to start with the C7 and C9s.