Lighting & Control

Where is the World’s Oldest Working Light Bulb?

June 21, 2021

As far as we know, it resides in a fire station in Livermore, Calif.

Did you know the world’s longest-burning light bulb reached 120 years recently? That’s right, and it passed 100,000 hours of service six years ago as well. What kind of lamp could last this long? An incandescent bulb. Yes, you read that one right. An incandescent was declared the oldest working light bulb by Guinness World Records and Ripley's Believe-It-or-Not.

The incandescent bulb's wall of fame at the fire station in Livermore, Calif. The timeline near the top of the ceiling chronicles events from the bulb's installation in 1900 to 2015 — when it reached 100,000 hours of service.

Installed in a fire station located near San Jose, Calif., in the small city of Livermore, it is deemed the oldest working incandescent bulb in the world. The lamp was first installed in 1901 in the old fire station and connected directly to the city’s power (subject to power surges).

It remained mostly turned on for 75 years until it moved to its current location — where it was connected to its own power source at 120V with a UPS back-up system.

Although the UPS failed once for several hours, when it turned back on, the bulb was using 60W again for the first few hours and then slowly dimmed to 4W. It doesn’t provide as much light as it used to — and the color of the bulb has changed over a century of use — but it is still working 24/7, gently lighting the space for fire trucks at night.

Interesting right? If you want to learn more, visitors are welcome. You can even take a picture with it! When I visited, the fireman on duty told me there were between two to five visitors per week, on average, all year long.

This incandescent bulb was declared the oldest working light bulb by Guinness World Records and Ripley's Believe-It-or-Not — 120 years.

For more information, visit www.centennialbulb.org. If you have questions, email [email protected] or contact the fire department directly at (925) 454-2361.

Will an incandescent be the last technology to last for more than 120 years and 100,000 hours of usage? With LED lighting, manufacturers have significantly improved performance and expected lifetime over other lamp technologies. Bets are on, but we will probably never know.

About the Author

Martin Mercier, P.Eng.

Mercier, P.Eng., is strategic marketing manager for IoT and connected systems for Cooper Lighting Solutions, a division of Signify (formerly known as Philips Lighting), based in Peachtree City, Ga. Previously, he was a senior product manager for advanced lighting technology systems for the Americas for eight years with Signify. Since his early days in R&D, he contributed to develop and launch the patented first Philips Lighting LED light engine plate-form deployed in multiple brands and manufacturing sites across the Americas. Shortly after, he helped to bring early cloud-based technology lighting systems for public and private customers in the Americas to market. His insights and ideas helped to strengthen the overall effort in pioneering new technologies for Signify and the lighting industry in general bringing problem-solving solutions for smart city and smart building customers. Detail-oriented and technically gifted, Martin studied electrical engineering at the renowned École de technology supérieure – the largest engineering school in Quebec. He can be reached at [email protected].