What’s old? How’d it start? What’s new and where’s it going? If you’ve ever wondered about the history of household light bulbs, join host Kevin O’Connor as master electrician Heath Eastman explains.
It All Started with Incandescent
The origins of lightbulbs reaches back to 1802, when a scientist applied battery-supplied electricity to a filament. The current heated the filament until it glowed, producing light. From there, scientists continued to work on producing a reliable light source, which eventually became the incandescent bulb.
The incandescent bulb’s make-up is similar to the original. Electricity is applied to the screw-in base, which then passes through the filament and creates heat and light. Unfortunately, 10% of the energy used produces light, while 90% just produces heat, making these lights inefficient—the reason why they’re being phased out.
As This Old House Magazine explained in its comprehensive guide to light bulbs, “Electricity passes through a tungsten filament inside a sealed glass bulb. The tungsten resists the electrical current, which causes the filament to heat up and glow, or ‘incandesce.’ Over time, it gets thinner and thinner until it finally breaks.” That gradual thinning of the filament is exactly why incandescent bulbs burn out — and why they rarely last more than a couple of years.
Then Came Fluorescent
The next major household bulb was the fluorescent bulb. These bulbs contain a gas mixture of mixture and phosphorus. When electricity is applied to the contacts at either end of the bulbs, the molecules inside the gas begin to produce light.
Fluorescent bulbs are much more efficient than incandescent bulbs (about five times more efficient), so engineers in the 1970s worked on producing a screw-in bulb that could fit in a typical light fixture yet produce fluorescent light. That’s when the pig-tail style bulbs we now know were created. But they, too, are being phased out for a more efficient option.
As This Old House electrician Heath Eastman explained, even traditional fluorescent tubes are becoming hard to find. When he visited a supply house to pick up older fluorescent tubes for a customer, he was told “they’re going to be more and more difficult to get, and I’m probably better off changing that fixture to something newer.” The phaseout applies to both the long tube-style fluorescents common in commercial settings and the compact screw-in CFLs that became household staples.
Today’s Most Efficient Options: LEDs
LED bulbs, or light-emitting diode bulbs, are the most efficient household bulb options we have now. These bulbs are essentially a series of small computer chips that produce light when electricity is applied. When they were first produced, they were ugly and came in strange, futuristic-looking designs. But today, they’re more subdued and capable of producing the same colors and light output as incandescent bulbs, though much more efficiently.
How much more efficient? In many cases, LED bulbs can be up to 10 times more efficient than incandescent bulbs. This is why they’re now the new standard for household bulbs.
Resources
Heath shows the evolution of household light bulbs by breaking them down into incandescent, fluorescent, and LED’s.
Incandescent bulbs are officially banned from being manufactured and sold in the USA. Fluorescents and CFL bulbs are the next to go so Heath doesn’t recommend buying those.
Why Incandescents Fell Behind: As Heath explained on This Old House, incandescent bulbs are remarkably inefficient — producing about 10% light and 90% heat. “So a lot of that energy is really being lost,” Heath noted. That inefficiency, combined with a lifespan of only a couple of years, made them ripe for replacement by newer technologies.
For LED, he showed classic LED bulbs, an LED Edison bulb with a spiral filament, and an LED tube light bulb.
Pro Tip: Heath points out that not all LED bulbs work in every fixture: “Where the bulb is totally enclosed by the glass, that’s an enclosed fixture or even if it’s mostly enclosed, it still can trap in a little bit of the heat in the back. You wanna make sure you get a bulb that’s built for the purpose.” Check the packaging to confirm your LED is rated for enclosed fixtures before installing.
The longest-running light bulb is the Centennial light bulb.
Heath shared a fun detail about the famous Centennial Light: “It started out as a 60-watt bulb. It’s down to a 4-watt. But it’s still there.” Located in a California firehouse, it has been running for over 100 years — a testament to the durability of simple filament design, even if modern LEDs far surpass incandescents in efficiency.
