LED lighting: The lowest hanging fruit in climate

By Michael Thomas

LED lighting: The lowest hanging fruit in climate

If you’ve read any of these newsletters or the Carbon Switch guides, you know that I’m a sucker for boring climate solutions.

Carbon-free steel, electric trucks that can charge your home, and long term energy storage is cool and all. But what really gets me excited is the boring stuff: heat pumpshybrid water heatersinsulation — the low-hanging fruit, the solutions we’ve already invented that can deliver billions of tons of carbon reductions right now.

And there’s no lower hanging fruit than the LED light bulb. The gigaton-scale climate solution most people don’t even consider a climate solution at all.

This week let’s talk about the surprisingly fun history of LEDs, what kind of carbon reductions they can deliver, and how you experience this climate solution first hand.

Haitz’s Law and accidental inventions

Nick Holonyak, Jr. didn’t mean to invent LED lighting.

In 1962, as an engineer at GE, he tried to create a visible semiconductor laser. Instead he ended up inventing an expensive, inefficient lamp. But despite this accident and the initial high price point, Holonyak knew his invention had big potential.

In 1963 he wrote an article for Reader’s Digest and argued that LEDs would eventually replace Thomas Edison’s incandescent light bulb. And he was right. It just took a lot longer than he expected.

For decades LEDs remained stubbornly expensive. The year of the accidental invention, in 1962, GE sold their first LED for $265. Four decades later LEDs were still inefficient and too expensive for commercial use. But by the turn of the millennium that all began to change.

In February of 2000, a group of lighting engineers gathered at a hotel just outside of San Francisco for the first LED conference. On the first day, a scientist named Roland Haidtz got up on stage and presented a chart. He showed that every decade the efficiency of LEDs had improved by an order of magnitude and their cost had fallen by an order of magnitude.

At the time a typical LED light bulb cost $100 compared to incandescent bulbs which cost a few bucks. Haidtz predicted that due to the dramatic fall in prices, those economics would change faster than anyone might expect. By 2020 he predicted manufacturers could make a bulb capable of producing 200 lumens per watt that cost a few dollars.

This prediction became known as Haidtz Law, a cousin of the more famous Moore’s Law in computing or Swanson’s Law in solar.

Haidtz’s prediction proved remarkably accurate. By 2010 Sylvania and Philips released their first 60-watt-equivalent LED bulb (the type of light bulb you’d want to put in a lamp). It cost $40 per bulb. A few years later, the same bulbs cost $15. And by 2017, Phillips released their first bulb with the magical 200 lumens per watt efficiency three years ahead of schedule. This weekend I picked up some LEDs for less than $3 per bulb.

In many ways LEDs are just another chapter in the story of technological development. If a common theme of literature is the Hero’s Journey, a common theme of technology is the “Learning Curve.” Most inventions start out almost comically expensive and inefficient. And they remain that way for decades. But as R&D investment and production volume grows, people learn how to drive down costs and increase efficiency. Then suddenly one day they are cheaper than anything else on the market.

Fortunately there are many climate solutions riding similar learning curves today. Solar, wind, batteries — all of these things were a joke a little more than a decade ago. Now even climate-denying utilities are deploying them at breakneck speed.

It’s easy to look at a climate solution in the beginning or middle of its learning curve and get pessimistic. “Companies will never pay $1,000 per ton to remove carbon.” “Electric planes are useless if they can only fly 400 miles.” But often climate solutions fall down the cost curve like humans fall in love or fall asleep: slowly, and then all at once.

From 30% to 100%

Still, the work of deploying technology — no matter how efficient or cheap it is — is difficult.

2020 was the first year that LEDs reached a majority of new lighting sales globally. The latest data gathered in the US put the LED penetration rate at about 30%. To avoid a climate disaster we need to speed this adoption up — fast.

If LEDs were installed in every lighting fixture around the world tomorrow, there’d be 800 million less metric tons of carbon emissions. In the US alone, we could save 431 terrawatt-hours (Twh) of electricity and 160 million metric tons of emissions.

Now let’s zoom into what this means for you as an individual.

A typical homeowner in America can save anywhere from $100-200 per year switching their lights to LEDs. That doesn’t sound like much. But LEDs last about 20 years. If you add up the utility bill savings and the savings from buying incandescent bulbs every 2 years, you’re looking at $3,000-4,000 — all for a few hundred dollar investment and 2-4 hours of work.

So what do you say we all replace our light bulbs this weekend and pick some of that low-hanging climate solution fruit?

A while ago, I published three different articles about LEDs that you can find here:

  • LED Lighting Buyer’s Guide — This article walks through how to replace your lights and what kind of bulbs to look for (it turns out lighting is a bit confusing!)
  • LED Temperature and Color Buyer’s Guide — This article will help you choose the right lights for every room (and avoid accidentally buying bulbs that make your bedroom look like a dentist office).
  • How Much Can You Save by Switching to LED Lighting? — This article goes through the numbers on how much most people are currently wasting on inefficient lighting. It’s a little nerdy, but if you like numbers you’ll like this one.

The tl;dr version

Ok, I get it. You’re a busy bee. So here’s the two minute version of everything you need to know about installing LEDs.

First things first, here are two important numbers to look at on a product label:

  • Lumens — This is how bright the bulb will be. For a bedroom aim for 400-500 lumens per bulb. For a living room: 700-800 lumens per bulb. For a kitchen, aim for a total of 3,000-4,000 lumens across all your bulbs.
  • Kelvin (K) — This is the temperature or warmth of a bulb, basically how blue, white or orange it is. If you want that soft warm light, aim for 2,700K. For a kitchen or bathroom go for more like 3000K – 4000K.

I planned to include a link to the LEDs I bought this weekend to make things easy, but everything I bought is out of stock (#supplychainproblems). So here are a couple options with similar specs to what I bought:

I’m planning to do a more in-depth review of the best LEDs out there for every room. But I hope that’s all helpful in the meantime.

Alright, that’s all for this week folks. I hope you enjoyed reading that brief history of LEDs as much I enjoyed researching and writing it.

As always, I’d love to hear from you. Do you have any recommendations on the best LEDs? What’s stopping you from installing LEDs? Are there other climate solutions you want me to research?

Have a great weekend!

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