Centennial Light

Centennial Light
Livermore's Centennial Light Bulb
TypeCarbon-filament
Working principle‍Incandescence

The Centennial Light is an incandescent light bulb recognized as the oldest known continuously operating light bulb. It was first illuminated in 1901, and has only been turned off a few brief times since. It is located at 4550 East Avenue, Livermore, California, and is open to public viewing.[1] Due to its longevity, the bulb has been noted by The Guinness Book of World Records,[2] Ripley's Believe It or Not!, and General Electric.[3] The light has been the subject of many TV shows and news reports along with at least four books, and has its own website.

The handmade lightbulb was originally manufactured by the Shelby Electric Company of Shelby, Ohio, towards the end of the 1890s and donated to the Livermore-Pleasanton Fire Department in 1901. It has been relocated several times since and remains in the care of the fire department to this day. The bulb's longevity has been attributed to the high quality of its manufacture,[4] it being seldom turned off,[5][6] and its low wattage.[5][6] Originally a 60-watt bulb, the light has for many years emitted dim light equivalent to a 4-watt bulb, about the strength of a nightlight.[4]

  1. ^ "Century Light Bulb". National Public Radio. June 10, 2001. Retrieved January 15, 2007.
  2. ^ Longest burning light bulb, Guinness World Records.
  3. ^ "The Little Bulb That Could... and Does", VIA, archived from the original (article) on January 3, 2010, retrieved January 27, 2007.
  4. ^ a b "Livermore's mysterious lightbulb burns 110 years".
  5. ^ a b Cite error: The named reference :1 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference :2 was invoked but never defined (see the help page).