LED light bulbs are replacing the old-fashioned, energy-inefficient incandescent lights that have been illuminating the world since the start of Thomas Edison. But how exactly do they work?LED light bulbs work differently than an incandescent light bulb in that they emit light through a solid semiconductor rather than a wire set inside a vacuum. When an electric charge hits an LED light bulb, it causes electrons to flow from a negatively-charged layer to a positively-charged one. Along the way, the flow of electrons emits light.
Some of the earlier LED bulbs were dimmer than their incandescent equivalents because the light was trapped inside, but currently, you can get good LED bulbs that put out as much light as a 60-watt incandescent, which is more than adequate for home lighting.
One of the great virtues of LED lighting is that the bulbs are very energy-efficient, sometimes 80 or so percent more than incandescent lights, which put out a lot of their energy as heat. Almost as important, an LED light will last 20 years. Combined, both qualities can save a lot of money in the long run.
LED lights used to be very expensive, roughly $100 a bulb. Even though you would save money in the long run, that would be a stiff up-front cost. Fortunately, as a quick look at the Home Depot page indicates, the price of LED light bulbs has collapsed far lower, between $10 and $20, in most cases.