Battle of the Bulb💡
A while back, I had the following question: Should I replace the lightbulbs in my house with LEDs?
I knew LEDs were the way to go, but didn't really know how much it mattered. Was it was a no-brainer, or was my money was better spent planting trees. etc.? At the time, I didn't really do any research and replaced some bulbs haphazardly. After doing a bit of research, here is the TLDR: Replace all your commonly-used lights with LEDs! Do it now, don't wait!
LEDs are extremely cheap relative to their efficiency, meaning you'll save a fair bit of energy. Less energy = less carbon, and it's easy as hell, and won't cost you money. Here are Wirecutter's best LED recs. They're $3.50 per and couldn't be easier to get.
How did I draw this conclusion? Well, goggles down friends, because we're going deep...
Does it matter?
In terms of climate change, residential lighting isn't super meaningful in the larger scheme of things. But, that's not quite the whole story. Allow me to indulge in an extended personal analogy (who could have seen this coming from me, really?) I used to think of my allergies - to cats, dust, ragweed, and pollen - as specific. I did everything I could to avoid each allergen. But I still suffered badly in spring and fall. Red-armed and itching at the allergist, I learned that I was allergic to everything: all trees, every kind of plant and animal at varying levels of severity. And that apparently, the body generates an allergic response when the combined allergens reach a threshold. It's an aggregate process - I’m not so super allergic to that one specific cat; the cat just pushed me over the top. The cat dander accrued to all the other allergens in my body. To be less allergic, I had to get pillow covers, comforter covers, change my HEPA filter regularly, etc. rather than just avoiding cats. Energy use, and consequent carbon footprint, feels similar. Any improvement helps. All progress counts.
Area man math:
Average energy usage for an American family is 10,972 KwH per year
Approximately 10% of household energy use in the US is lighting (or 1,097 KwH per year)
Swapping out incandescents for LEDs = 1097 KwH * 85% = 932 KwH saved annually per household
So what?
Well, about one pound of CO2 is released per KwH (apparently depends a fair bit on your local grid) which means ~900 lbs of CO2 that would have been released per year could be avoided. For context, I tried to figure out how much carbon there is in a tree, and couldn't find an easy answer. But according to the Sierra Club, 900 lbs of CO2 is at least two 25-year old silver maples. Or, according to a bunch of crazy math I did*, it's approximately one red oak that's 15 inches in diameter and 40 feet tall. Further context: assuming you cut down that single tree and turned it into firewood, you'd be able to heat my parent's house for a month during Vermont winter with it.
Warning, very deep…
What about embodied carbon in the manufacturing and retail process of the new LED - does that offset potential gains ? Turns out that LEDs aren't like cars or batteries. They're cheap and not energy intensive to manufacture, and cheap to ship and store. There is an impressive amount of information out there, for example, here, in this back-breakingly rigorous academic rundown of how and when to replace your lightbulbs.
Does it actually make financial sense?
Yes. From slightly, to very much so, with the variables being if you 1) have lots of lights in your house and currently use incandescents or halogens, and 2) are going to own your house for the a while.
Non-Area man math:
We spend about $100 a month on electricity, more in winter, less in summer. So, that's about $1,200, which means $120 is spent, over the course of the year, on lighting. I'm going to assume currently half of my lights are LEDs, which means I'm spending, and I've very much estimating here, $100 a year on bad lights, which could be replaced, and drive down my costs by about $85, over the course of the year. So, I save $85, and have to buy new lights.
From a money perspective - year one, I probably am a little net negative on account of buying a pile of LEDs. Year two up a bit. Long run, they say you could save $80 per bulb over 25 years. If you have twenty bulbs that means $64 a year for 25 years.
Upshot? Low investment, solid ROI. You probably won't notice much of a difference in savings. If you do, very likely to be in the few bucks a month range. I'll take it.
But are they ugly?
It's worth mentioning here that I am sensitive to the color of light, and can be picky. I used to find the "warm" LEDs abrasive and white. But now you can get 2700K. At 2700K or warmer they don't feel hospital-ly to me. 3000K is fine but a little white, above that is unpleasant for me. Fear not, they’re not ugly if you pay attention to which LEDs you buy - choose 2700K or warmer.
Have exposed bulbs? They have very nice Edison-style LED bulbs now too. Here.
In sum, why do it now?
No downside: We're likely going to have to sacrifice in the future. For our children, for the planet, for our parents. This isn't one of those times. You get 1) the same light, 2) for less money, 3) while helping the planet, 4) at a low up-front cost.
Change your bulb, change your mind: Like my allergy example, it all counts. Particularly, it counts more if it changes your mind - how you think about using energy, what that energy means and adds up to, and how to seize opportunities to use less of it. More mental foothold than important first step.
Market signal: So I didn't really understand this, but apparently LED tech is improving really rapidly still, which means that more money spent on LEDs will lead to more R&D, and contribute to improving future technology. Definitely a market signal we want to send.
A parting holiday thought:
Are you going home for the holidays? Want to give your parents a wonderful gift? Order a whole pile of LEDs and have them sent to your folks’ place. Help them swap all the lights out, as I think actually doing it is the hardest part for most people. It’ll lower their electric bill, and you’ll get to prove your handiness.
As always, please let me know what you think!
*Addition: 12-18
An old family friend asked if she should donate or recycle or throw away her old incandescents. Good question! I did a little poking around and the answer is: Recycle them. Think of them as eighteen wheelers - we need to get them off the road entirely, so donating them doesn’t help. Incandescents are not toxic, so you can throw them in the trash, but it looks like recycling is an option, so let’s go with that. How? Some curbside will accept it (decisions made by local recycling providers) and transfer stations generally do. I haven’t found a reliable online search for this, however, so calling around may currently be best practice.