Incandescent vs. LED Lighting: What’s the Difference?

Buying light bulbs today can be confusing. Gone are the days when your only decision was between a 100-watt and a 60-watt incandescent. Instead, there are all kinds of lighting options at the home improvement or hardware store, from vibrant colors and designer shapes to smart bulbs you control from your phone. I’m a licensed electrician, and I get confused by the options sometimes even though I’ve installed thousands of lights.

If you regularly buy incandescents, you’ve probably noticed they haven’t been on the shelf for a while. You may even have heard that they’re being squeezed out in favor of light-emitting diode (LED) technology. It’s true. But even as old tech makes way for new, you may still be curious about the differences between them.

We talked to three lighting experts with decades of experience with both lighting types. Here’s what you need to know.

What Is Incandescent Lighting?

Incandescent lights produce light by generating heat. Terry McGowan, director of engineering at the American Lighting Association, says that in the early days of electric lighting, the incandescent light was colloquially called a “hot wire in a bottle”. Things have mostly stayed the same since then. There’s a glass globe, and inside of that is a tiny wire called a filament. Turning on the light forces electricity through the filament, which heats up and glows brightly.

How Incandescent Lighting Works

Incandescent lighting works because it’s harder for electricity to flow through the filament than your home’s electrical wires. When you flip the switch and the electrical current reaches the bulb, the filament acts like a big brake, slowing (aka resisting) the current. This energy needs somewhere to go, so it turns into heat (and light). If you’ve ever looked inside a pop-up toaster to see the red-hot wires browning your toast, it’s the same concept.

Pros and Cons of Incandescent Lighting

Incandescent lighting gives off a warm, comforting light that people love. Incandescent bulbs are cheap to produce… or they used to be, at least. Incandescent light bulbs don’t meet current federal efficiency standards, so as of August 2023, they’re no longer sold in the U.S. except in special-use applications, such as oven lights. (McGowan says that’s because incandescents withstand heat better than other lights.)

Incandescents are relatively short-lived compared to other lights, and George Yianni, chief technology officer at Philips Hue Lighting, says they lose a lot of heat. Only 5–10% of their energy use is actually converted into light. Yianni says the typical lifespan is between 750 and 2,000 hours. So, if you factor in the amount of energy needed to make up for the heat loss and the number of replacement bulbs you’ll have to buy, they cost more in the long run.

What Is LED Lighting?

Light-emitting diodes (LED) are little chips of metal and metal alloys painted with a substance that glows when electricity moves through the diodes. “It’s an entirely different way of creating light, unlike anything else we have,” according to Dara Greaney, founder of LED Light Expert. There’s no filament and almost no heat: “90% of the energy LEDs use is converted into light,” Greaney says.

How LED Lighting Works

The tiny chips that make up an LED light can be attached directly to the light fixture housing, so there’s no need for a delicate glass globe or a glowing filament. “When the electricity flows, light is emitted directly from the surface of the LED,” McGowan says. The coating on the LED, called a phosphor, can be manipulated to produce white light or colors by mixing phosphors that produce red, green or blue.

Pros and Cons of LED Lighting

The biggest pro is energy efficiency. LEDs give off more light (measured in lumens) per unit of energy (measured in watts) than any other available lighting type. “LED light sources with good color characteristics are now commonly rated for 120-150 lumens/watt,” McGowan says. That’s ten times more than an incandescent.

Another pro? “LED lights can be smart, allowing you further customization and energy efficiency,” Yianni says. Yianni points to how dimming a smart LED bulb to 70% brightness cuts their already low energy use by 51%. Setting them to “colors other than white can not only set the mood but also reduce their energy consumption by up to 79%,” Yianni says.

And while early LED technology was costly and faced complaints of stark, sterile ugliness, Greaney says costs have come way down. Today’s LEDs offer warmth and multiple color options. One con is that LED light is highly directional, but Greaney says a frosted cover will diffuse the light naturally.

What’s the Difference Between Incandescent and LED Lighting?

They both produce light, but the similarities mostly end there. Here’s how they stack up head to head:

• Energy efficiency: LEDs produce ten times more light per watt of energy than incandescents.
• Lifespan: According to Yianni, LEDs last “25,000 to 50,000 hours compared to the 750 to 2,000 hours of incandescent bulbs.”
• Versatility: The flexibility and durability of LEDs mean they work across many applications, including general lighting, signage, flashlights, Christmas lights and electronics. Still, incandescent lights are better for specific uses like ovens and bug lights.
• Color rendering: This is where incandescents shine. They’re not very efficient, but “colors look great,” Greaney says. LEDs are catching up, though, “so this benefit is going away.”

Which Is Better, Incandescent or LED Lighting?

LED lighting is better in almost every use case. Incandescent lighting is beloved due to its warmth and because it’s been a staple of our lives for generations. But LED lighting has come a long way from the cold, sterile, “blue” light of early iterations, Greaney says. Look on the label for a high Color Rendering Index and a warm temperature and you’ll get a great light.

But the biggest reason to love LEDs? Their energy efficiency and long life. More than ten times the efficiency as incandescents, LEDs and their dizzying array of colors and styles are the clear winner.

About the Experts

Terry McGowan is the director of engineering at the American Lighting Association. McGowan previously worked at GE Lighting, runs his own lighting design and consulting business and is involved with the International Dark Sky Association and the American Lighting Bureau.

George Yianni is the chief technology officer at Philips Hue, where he developed the smart Hue lighting system. Previously, Yianni worked as a project manager and architect for Phillips Lighting, focusing on lighting controls and connectivity.

Dara Greaney is the CEO and founder of LED Light Expert, an e-commerce lighting retailer. His expertise includes lighting design and LED technology, with a commitment toward sustainability and energy efficiency.