In Bloomington, Minnesota, a brilliantly lit 57-foot oak tree greets commuters passing by on Highway 77. Bob and Julie Little, who have painstakingly wound the tree with 40,000 holiday lights, told the Minneapolis Star Tribune that they call the tree their “Christmas card to the world.”
After a storm last winter wiped out much of the display last year, though, the Littles made a decision to switch to LED lights. The new bulbs are brighter, more durable, and use a lot less energy.
How much less?
Using an online calculator from HolidayLEDs.com, we can make a rough estimation.
The tree has 40,000 bulbs. It’s on from 5 a.m. to 7 a.m. and 5 p.m. to midnight from Thanksgiving to New Year’s, which is about 333 hours total. And for simplicity’s sake, we’ll use an electricity price of 10 cents per kilowatt hour.
If the old bulbs were relatively efficient 1-watt mini-bulbs, the display would use approximately 13,320 kilowatt hours of energy, at a cost of roughly $1,332 for the season.
LED holiday lights are about .07 watts each. That drops the energy use to 932 kilowatt hours, for an electric bill of only $93.20 — a cost savings of 93%. Ho ho ho!
Of course, the energy savings come with a tradeoff – LED lights are quite a bit more expensive than incandescents. Depending on the quality of bulbs the Littles bought, the full cost of the display could run as much as $30,000. Bob Little told the Star Tribune in 2009 that he estimated a 30-year payoff for LEDs, which he figured cost 6 times more than the lights he was using. If we only look at the cost of the new bulbs vs. the energy savings, our calculations appear to be pretty close.
But is that 30-year payoff correct? let’s go back to the numbers.
Little said in 2009 that he was spending about $2,500 a year to replace broken or burned-out bulbs. Assume that continues for 30 years. He’d pay $75,000 for new bulbs, plus almost $40,000 for the electricity (for the sake of simplicity, let’s ignore inflation) – a total – brace yourself – of $115,000. The LEDs, which won’t need to be replaced nearly as often, would cost $30,000, plus $2,800 for the energy. Even if Little had to replace the LEDs every decade, he’d still come out ahead.
But clearly, for the Littles, the money isn’t a concern. From the 2009 Star Tribune article:
“It’s so wonderful for the soul,” Bob Little said. “You only have to see a crippled girl get out of a van at the end of the driveway … and operate this wheelchair, coming up the driveway. Our driveway is 100 yards long. And then you hear her say: ‘Daddy, could we move here? Because this is awesome.’ What better Christmas present can we get?”
Thanks, Bob and Julie, for making the holidays a little brighter (and a little greener).