How to Light Bulbs Work: The Science Behind the Invention

The invention of the light bulb was a real breakthrough in the late 1800s. Although electricity was being produced through chemical reactions and mechanically generated, there weren’t many uses for it. Early electrical pioneers discovered that electrical currents could make a wire glow, but the wire would eventually disintegrate. The light bulb was the solution that protected the wire and provided light at the flick of a switch.

The light bulb was invented simultaneously on both sides of the Atlantic in the 1870s by Joseph Swan and Thomas Edison. The light bulb’s basic design has barely changed since then. It is made of thin glass and contains a wire filament, usually made from tungsten, wound in a coil pattern. Early light bulbs contained a partial vacuum, which was later replaced by an inert gas that doesn’t react with the white-hot element, to reduce the potential for an oxidizing reaction to take place.

The result is a bulb that can provide up to 1000 hours of light or even more. Some light bulbs manufactured in the late 1800s are still in daily use today, over 130 years later. However, the light bulb is not very efficient; over 90% of the energy it consumes is converted into heat, with only a small amount of visible light as a by-product.

In recent years, more efficient compact fluorescent ‘energy-saving’ light bulbs and LED-based lights have become more popular. The production and sale of old incandescent light bulbs are regulated in many countries, with believers in the old ways having to buy in stocks of bulbs for the future. Even in the automotive industry, LED-based lights are replacing traditional bulbs.

The humble light bulb has become a threatened species, with more modern and efficient alternatives available. While the light bulb will always be remembered as a significant invention, it’s clear that the future of lighting is moving towards more eco-friendly and energy-efficient options.