Here’s why energy saving light bulbs have become so popular and how they light up our homes, schools and workplaces.
Energy saving light bulbs were invented as a greener alternative to traditional bulbs, needing 90% less electricity to produce the same light, according to the Center of Sustainable Energy. But how do they do it?
As bright ideas go, it’s almost impossible to overstate the impact the humble light bulb has had on human civilization. Before Thomas Edison had the original ‘light bulb moment’ and patented his invention all the way back in 1879 people were literally living in the dark ages, according to the Franklin Institute. People depended on oil or gas lamps and candles to light their rooms and streets, and when the sun went down, the world would look much duller than it does today.
The light bulb changed all that and enabled us to have cheap, reliable and powerful lighting at the flick of a switch. They revolutionized how we work and relax after dark, impacting how we build our streets and all of our modern buildings too and ensuring that when the sun goes down, life goes on.
A traditional or 'incandescent' light bulb, consists of a piece of hardy metal wire with a very high melting point, typically made of tungsten, surrounded by a glass cover, according to the BBC. When electricity passes through it, it makes the wire glow, producing the light that fills the room. If you imagine a poker glowing red after being held in a fire, that’s pretty much what the inside of the light bulb and how it emits light.
One of the problems with traditional bulbs, however, is that much of the energy they use is not actually turned into light, but heat, which is why you have to wait for them to cool down before changing them. Only 10% of the energy an incandescent light bulb uses is turned into light, according to Penn State University. This makes them extremely inefficient for what we actually need them to do — after all, nobody turns on a light to stay warm, do they?
Also, the heat irreparably damages the filament to a point where it no longer works, the lightbulb breaks and has to be replaced. This has huge implications for both waste and cost.
So for many years, scientists and engineers have been working on replacements for the traditional light bulb that would be kinder to the environment without compromising on effectiveness.
Certain types of energy saving light bulbs have actually been around for decades. One of the first was the halogen bulb developed in 1955, according to the Edison Tech Center.
They use the same filament technology as traditional bulbs but have some important differences.
Halogen bulbs are similar to incandescent bulbs but contain a small amount of halogen gas which mixes with tungsten vapor. It then deposits it back onto the filament instead of on the inside of the bulb, meaning it can shine more brightly and extends the bulb's lifespan
These bulbs light up when an electric current is passed through a tube containing a gas called argon and a tiny amount of mercury vapor. This process then generates ultraviolet light which is invisible but which excites the molecules in a fluorescent coating — called phosphor — on the inside of the tube, which then emits visible light, according to the National Institute of Environmental Health Sciences. They marked a big step forward in energy saving technology and are still the most commonly used type of energy saving bulb in use today.
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