Calculating energy savings for LED holiday lighting

We frequently help our holiday lighting customers analyze the cost savings that can be achieved by using LED lights instead of traditional incandescent lighting. The calculations to determine the cost savings are not very complicated, but it is a lot easier with a good conversion calculator handy. Here’s the data you will need to perform this calculation:

1. Total number of bulbs;
2. Wattage of the individual incandescent bulbs to be replaced. (C9s are generally about 8-9 watts; C7s are generally about 6-7 watts; and mini lights are usually between .50 and 1 watt)
3. Amount of time the bulbs will be illuminated; and
4. The average cost of a kilowatt-hour of electricity in your area. ($.07 is an average rate for Seattle residents.)

Step 1: Calculate total watts

Multiple the total number of bulbs by the wattage of 1 bulb. This equals the total watts of the display.

Step 2: Enter data into conversion calculator

Enter the product of the formula in Step 1 into the “Watts” field in this calculator: http://mhi-inc.com/Converter/watt_calculator.htm. Next, enter the total amount of time the lights will be illuminated in the “Time” section of the calculator. (Note that the time can be in seconds, minutes, hours, days, months, or years.)

This calculator will calculate the total kilowatt-hours consumed by this lighting display.

Step 3: Determine cost of electricity

Multiple the total kilowatt-hours the display will consume (as determined by the calculator in Step 2) and multiply it by the average cost of a kilowatt hour of electricity in your area.

Step 4: Determine to cost to operate Christmas lights using LEDs

Repeat steps 1-3. The average LED holiday style light is between .05 and .07 watts.

Step 5: Calculate the savings

Subtract the cost of operating the LED lights from the cost of operating the incandescent lights. This is the total cost savings you can expect by switching to LEDs.