Christmas lights create a festive mood for your home or business.  They can also help your business to be noticed and attract customers, especially during our long dark nights in Hawaii.  Interior lights create an inviting mood and memories for people to return.  The lighting can help improve visibility for your customers to see your products, or to read the menu.  In short, they may help to bring you new business, and repeat business, during this competitive time. 

Two types of Christmas lights are most commonly used now: “mini-lights” or LED lights.  The energy difference is enormous; old fashioned mini-lights consume 10 times the energy of newer LEDs.

Mini-lights:  Typical energy use = 20 watts per 50-bulb-string = 0.4 watts/bulb

LEDs:  Typical energy use = 2.5 watts per 60-bulb-string = 0.041667 watts/bulb

Mini-light configurations include the typical light string, as well as light curtains and icicle lights, and most strings have 50, 100 or 150 bulbs per string.  The LEDs are typically configured as 60-bulb strings.

With the LEDs so much more energy-efficient, should you buy new lights?  That depends on the number of lights you are buying, the price per string, and how many years of use you expect for your lights.

Here are the comparison calculations, assuming the cost of energy is 30-cents per kilowatt hour. For this comparison, we are assuming 1,000 bulbs on for 6 hours per day for 30 days in the month.

For mini-lights:
= 0.4 Watt/bulb x 1000 bulbs x 6 hours/day
= 2400 Watt-hours / 1000 = 2.4 kWh per day. 
X 30 days/ month = 72 kWh / month
X $0.30/kWh = $21.60 to operate.
In this case, 1,000 mini-lights consume 72 kWh and cost $21.60 to operate.

For LED lights:
= .041667 Watt/bulb x 1000 bulbs x 6 hours/day
= 250 Watt-hours / 1000 = 0.25 kWh per day. 
X 30 days/ month = 7.5 kWh / month
X $0.30/kWh = $2.25 to operate.
In our example, the 1,000 LEDs consume 7.5 kWh, and cost $2.25 to operate.

The operating savings is $19.35 per month. Results will vary based on the actual cost of  electricity.  With this information, you can determine when the monthly savings-per-1,000-lights justifies the investment in new lights.

May your holidays be bright, safe, healthy and happy!