How LED Lights Became So Cheap

And a fun story about accidental innovation

Last week, a consequential federal climate policy went into effect without much notice or media coverage. 

On Tuesday, new federal rules banned the sale of virtually all incandescent light bulbs. Going forward, consumers will instead have to purchase more energy efficient LED bulbs that use a fraction of the electricity and last five times as long. 

Federal rules that improve energy efficiency in buildings like this aren’t glamorous, but they are remarkably effective.

Since the 1970s the federal government has passed laws requiring buildings and appliances to become more efficient. Homes today, one of the largest sources of greenhouse gas emissions in the country, use about a third less energy per square foot than they did five decades ago. (These gains have been largely offset by the rise of American McMansions—but hey, at least our McMansions are efficient!)

Biden’s bulb ban will accelerate the trend of more efficient homes. The new rule is expected to cut 222 million tons of carbon dioxide emissions by 2050, according to the Department of Energy, equivalent to the annual emissions of 28 million homes. 

That a climate policy like this passed without much backlash is a testament to the remarkable progress in LED lighting technology in recent years. 

No one really cares that they can’t buy an incandescent bulb anymore because they can buy a far more superior LED bulb. Even more importantly, Americans are accustomed to this superior alternative. In 2020, 47% of all light bulbs in U.S. homes were LEDs, up from just 4% in 2015. 

For much of the last half century, the idea that LED lights would replace every bulb in America was a preposterous one. Like so many other climate solutions, LEDs rose from obscurity to dominance like humans fall asleep: slowly, then all at once. 

The accidental invention of LEDs

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 almost immediately, Holonyak knew his accidental invention had big potential.

In 1963, he was quoted in an article by Reader’s Digest arguing that LEDs would eventually replace Thomas Edison’s incandescent light bulb. 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 $260. 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 Haitz 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. Haitz 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 Haitz Law, a cousin of the more famous Moore’s Law in computing or Swanson’s Law in solar.

Haitz’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. By 2017, Phillips released their first bulb with the magical 200 lumens per watt efficiency three years ahead of schedule. Today, you can buy an LED light bulb for less than $2. 

As the price of LEDs fell, they became increasingly popular. In 2020, just ten years after the first LEDs hit the market, the more efficient bulbs captured 69% of the new light bulb market. 

“The rapid adoption of LEDs in lighting marks one of the fastest technology shifts in human history,” Goldman Sachs analysts wrote in a 2016 report. 

From unthinkable to inevitable

Many important climate solutions are today where LEDs were a decade ago. Less than 1% of cars in America are electric. 3.7% of homes have solar panels on their roof. 11% of primary energy is generated from renewable sources. 

It’s easy to look at these numbers and feel hopeless—especially during a hot El Nino summer when it seems like our planet is spiraling towards climate collapse. But to succumb to doomerism or apathy is to miss the full picture of climate change.

LEDs won’t solve all our problems. The story of this technology does, however, prove that change is possible, and sometimes the distance between unthinkable and inevitable is smaller than one might think.