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History of the Light bulb
Video courtesy of the Department of Energy
U.S. Department of Energy


 Direct Current Podcast: Season 2





MATT DOZIER: Welcome to another Direct Current Short Circuit - your quick energy boost in audio form. I’m Matt Dozier.

ALLISON LANTERO: And I’m Allison Lantero. This short circuit is devoted to one of the most ubiquitous items in the world, an item you can probably see from wherever you’re listening...

DOZIER: We’re talking about the light bulb.

LANTERO: That’s right. The story of how the light bulb came to light is a fascinating one that we think even a child could understand.

DOZIER: So with that, stick around for an… illuminating... tale of a mother, child and some particularly enlightened bulbs.


(Car pulls up, stops and then a car door opens and closes.)


(Music plays)

MOTHER: So what did you learn at school today?


(The sound of paper bag being picked up)

SON: We’re learning about electricity!

MOTHER: Really? And what did you learn about electricity?

SON: Well, Thomas Edison invented the lightbulb and then he turned it into a grid…

MOTHER: Hmmm, that’s not quite right.

SON: It’s not? Then who did?

MOTHER: Well, that’s a tough one. No one person can be credited with creating it.


MOTHER: (unscrewing light bulb) Now, you see this bulb that I'm taking out of this lamp, its called an incandescent light bulb.

SON: In-can-dess-dant. Can-dess-ment. (he tries to say incandescent but can’t really say it)

MOTHER: (laughs) Close. Let’s call this light bulb Arc.

MOTHER doing ARC voice: Pleased to meet you Noah.


(SON laughs)

ARC: I was invented by a man named Humphry Davy. Around the year 1809... Gee that’s a long time ago when you say it out loud. He demonstrated the first incandescent light to the Royal Institute in Great Britain, using a bank of batteries and two charcoal rods. ARC lamps, like me, provided many cities with their first electric streetlights.


SON: Pleased to meet you Mr. Arc, I’m Noah!


ARC: Pleased to meet you Noah... I look a little different than I did in those days. In 1904, I got a new filament -- that’s the part of me that heats up to create light. Someone figured out that tungsten filaments lasted longer, were brighter, and more efficient than lamps with carbon filaments. A man name Irving Langmuir filled me with gas.


SON: (giggles) He said gas.

ARC: Well yes! Langmuir realized that inert gas like nitrogen doubled my efficiency. This means I provide the same amount of light but use a lot less energy!


SON: (still giggling) But wait, then why is Thomas Edison famous.


MOTHER: Well, Edison did help improve the lightbulb, but he also focused on the entire lighting system. He showed that you could make electricity in one place and then send it to lots of homes and buildings.


SON: Like powerlines?


MOTHER: Exactly! He actually developed the first power plant, it was called Pearl Street Station.

SON: OK, so why are there some lightbulbs that look like ARC, and then others that are long skinny tubes like the ones at school?


MOTHER: That’s a great question. In the 1800s, two German scientists discovered that they could produce light by removing almost all of the air from a long glass tube and passing an electrical current through it. They called it a GEISSLER tube, let’s see if I can find a picture online.


SON: Can he have a voice too?


GEISSLER voice: Hi, I’m Geissler. I make up the basis of most fluorescent lights, like the ones in schools and office buildings. By 1951, I was way more popular than my grandpa ARC, mostly because people needed efficient lighting during World War II.


SON: OK, so what about the weird curly lights?


MOTHER: Well, the weird curly lights are Arc’s granddaughter, C-F-...Ellie.


CF-Ellie voice: Hey there!


SON: When were you born?


CF-Ellie: I was born in 1976. Edward Hammer at General Electric figured out how to bend the fluorescent tube into a spiral shape, creating the first compact fluorescent light or as we call it CFL. I hit the market in the mid-1980s and ranged from $25-$35 a bulb.  


SON: That sounds like a lot of money.


CF-Ellie: It was, but we live a lot longer than ARC lamps, but can fit in the same fixtures.


SON: Aw, so ARC got replaced?

ARC: Well Noah, I look at it more like a retirement. These young whippersnappers outrun me every time, so I’m ok with it. In fact, my great-great-granddaughter LEDdie is in the bag over there.


(sound of paper bag rustling)


SON: This one, Mommy?


ARC: Yep, that’s LEDdie.


SON: And how do you fit into this whole story?

ARC: Well back in 1962…

SON: I asked LEDdie.


MOTHER: Oh right.


LEDdie voice: Well, the first three letters of my name, L-E-D, stand for light-emitting diode. And I’m technically older than CF-Ellie, but back then I was only able to shine red.


SON: Back when?

LEDdie: Oh, way back in 1962. That’s when Nick Holonyak, Jr. at General Electric invented me. I shined yellow, then green, but for decades no one could figure out how to make me shine white. And what that means an even balance of all the different colors in the visible spectrum.


SON: What changed?

LEDdie: Well, they invented blue LEDs, and then in the 1990s scientists figured out they could coat bulbs like me in a substance called a phosphor to make us shine white. I need 75% less energy and last 25 times longer compared  to incandescent lighting. That’s because I don’t waste heat like other types of bulbs. We’re talking 90% less than incandescents and 80% less than CFLs.


But that’s not all! I can fit into the same fixtures as CF-Ellie. Since 2008, I’m 85 percent cheaper, and most recently, a number of stores announced that they will be selling me for $10 or less. That’s a bargain.


SON: Wow, even I have $10.


MOTHER: (laughs) Yeah, but I’m not going to make you spend that on light bulbs sweetheart. Lights like LEDdie also save Mommy money on our electric bill, meaning I can buy you more clothes and toys and candy.


(Kid giggles, small feet and then keys jingle.)


SON: Here’s your keys mommie.


MOTHER: Where are we going?


(footsteps running keys jingle)


SON: We need to go get more LEDdie, and then maybe we can stop by the toy store.

MOM: Huh! Cute.




DOZIER: It’s time to turn out the lights on this episode of Direct Current. You can learn all about the history of the light bulb, including an interactive timeline, at While you’re there, you can find plenty of other fascinating energy stories.

LANTERO: And if you have questions about this episode or any other episode you can email us at or tweet @ENERGY. If you’re enjoying Direct Current, help us spread the word! Tell your friends about the show, and leave us a rating or review on iTunes. We appreciate the feedback.

DOZIER: We’d like to give a big thank-you to Vernon Herron for writing this episode.

LANTERO: And another big thank you to our cast of characters. The mother and son duo were played by Faiza Akhtar and her son Noah. ARC was played by Ernie Ambrose. Vernon Herron played the role of Geissler. CF-Ellie was played by Bianca Ktenas, and Cort Kreer was Leddie.


DOZIER: Direct Current is produced by Simon Edelman, Allison Lantero and me, Matt Dozier. Art and design by Cort Kreer. With Support from Paul Lester, Ernie Ambrose, and Atiq Warraich.


LANTERO: We’re a production of the U.S. Department of Energy and published from our nation’s capitol in Washington, D.C.

DOZIER: Until next time, thanks for listening!




We devote this Short Circuit to one of the most ubiquitous items in the world.

It's an item you can probably see from wherever you’re listening… the light bulb! The story of how the light bulb came to light is a fascinating one that we think even a child could understand. The History of The Light Bulb is an illuminating tale of a mother, child and some particularly enlightened bulbs.

After you've listened to the episode, explore the light bulb's evolution with our interactive timeline:

Then, get the scoop on the best lighting choices for your home or business with the help of our EnergySaver program:

Finally, dive into the ever-expanding world of ultra-efficient LED lighting, and the wide range of Energy Department-funded R&D projects helping drive the technology forward.