About a year and a half ago I moved into a new house, with much of the lighting provided by incandescent bulbs. As they burned out, I replaced them with LED bulbs with the intention of never touching them again, and saving a little bit of power… After some quick math though, I quickly ordered and replaced 12 more bulbs, realizing that I was throwing away a lot of money for no apparent reason.
The Money Math Revelation:
In my kitchen, I had 5 incandescent floodlight bulbs at 65W each, plus another 10 in the “formal dining room” AKA kid’s playroom. This gives a total lighting draw of 975W (let’s round up to a full kilowatt) and if each is turned on for 5 hours a day, 5 kilowatt hours (kWh) of energy used. Average price of electricity in the US is around $.10/kWh, so $.50/day for lighting these rooms.
This doesn’t sound so bad, but multiplied by 365 days/year, that gives $182.5 that I’m spending to power these lights/year. The new LEDs that I purchased (Amazon) work off of 11 watts, giving a total power of 165W, roughly 17% of the previous number. So spending in the future on these lights will be around $31, or a savings of $151.5/year at a cost of $55.82 in lights.
Taking this further, consider that your air conditioning unit doesn’t have to cool your house from these lights (especially in hotter climates), so savings are actually a bit higher than this for me being in Florida. The lights that I purchased last up to 10,000 hours, so based on 5 hours/day usage, they should last for over 5 years (or well over 20 years at 3 hours/day per the description, which seems a bit inconsistent)*, so if you multiply this savings out by 5, I’ll be saving over $750 over the life of these lights.
Time for LEDs? Absolutely
This effect is even larger for 100W bulbs (Amazon- these from Philips look good, but not sure which kind I have). While I’ve been replacing lighting with LEDs as needed, I didn’t bother to calculate things out at the time. Just be sure to select the right temperature — I went with 2700k — and dimmable if you need them, since you’ll have the bulbs around for a long, long time.
While LEDs were initially too expensive to consider, and CFLs were a disaster IMO for several reasons that I won’t get into here, it’s time to consider better lighting. While if you only have a light or two to consider it might not make a big difference, but in medium or largish houses the effect could be tremendous.
Note that links to Amazon are affiliate, so I get a small percentage of purchases at no additional cost to you.
*Edit 1/2/2020: Having had these bulbs for a while, they seem to be making an impact, helped along I’m sure by my new water heater. That being said, two of these lights have started to malfunction, so the promise of “20 years” seems extremely optimistic. I think they’re under warranty, but I doubt I’ll go through the hassle of figuring that out. Still worth the price, but a bit disappointing.
*Edit 3/22/2020: After a few more failed, I contacted the manufacturer, and they sent me new bulbs without having to send them back. None of the new ones have had an issue, so perhaps it was a bad batch, or a defect that they’ve since fixed. So I’m no longer disappointed :-).