When we talk about the history of lighting and humans we need to understand that humans include all hominids. People first began using fire about 800,000 years ago. Fire was used for lighting, heat, and cooking. The use of fire for cooking vastly improved the diet of humans and resulted in rapid evolution of the human brain. The availability of light from fires changed sleep patterns of humans. The necessity of keeping camp fires burning all night also helped change sleep patterns. Camp fires kept dangerous animals away. Camp fires also probably had an effect on the evolution of dogs since they evolved from camp followers who became domesticated.
The development of better light in the form of oil lamps and candles helped develop civilization. Large cities don't function very well with nothing but wood fires for lighting. Various oil lamps and eventually kerosene lamps had an immense effect on civilization. Whale oil drove a large industry for several centuries and the petroleum industry still dominates much of world economy.
Although electric lighting was first developed in the early 19th century it was not until the early 20th century that it began to be widely distributed. The broad distribution of electric power and lighting was funded by the American people through their government to the considerable profit of a number of wealthy industrialists, much as with the rail system and a number of other industries. Electric lighting came in several different forms. The primary form was incandescent lighting, which uses a filament usually made of metal heated by electrical current. Close behind that was fluorescent lighting, followed by gas-discharge such as neon lighting, and arc lighting.
By the mid 20th century two other forms of lighting began to emerge. One of these, electroluminescence, is primarily used for lighting instrument panels and advertising displays. It is not very useful for lighting even though electroluminescent night lights were available until light emitting diode technology began to develop.
By the beginning of the 21st century developed nations began to try to phase out the use of incandescent lighting because of the extremely poor efficiency of incandescent lighting, usually about 5%. That means that only about 5% of the energy consumed by the lamp is converted into visible light with most of the rest being converted into heat. This compares to up to 60% efficiency for compact fluorescent light bulbs. Many incandescent lights produce so much heat that they can be a fire hazard. Some incandescent bulbs are used for heating purposes.
The initial push to replace incandescent light bulbs was centered on the compact fluorescent light (CFL) bulb. Tube type fluorescent lights have long been used for commercial lighting. A compact fluorescent bulb produces about five times as much light as an incandescent bulb consuming the same amount of electricity. The compact fluorescent lasts about seven to eight times as long. The one environmental concern with all fluorescent lights is that they contain mercury, a toxic environmental concern. Of course, coal burning power plants release mercury and other serious toxins so the danger of accidental release of mercury from fluorescent lights is at least partially offset by the reduction of environmental harm from power plants.
Recently the move to eliminating incandescent lighting has begun to shift to the use of light emitting diodes or LEDs. These lights are almost twice as efficient as CF Ls and last at least 5 times longer. Currently an LED bulb is more expensive than a CFL but considerably cheaper in the long run. Just as the price of CFLs has plummeted in just a few years the cost of LEDs is rapidly falling.
One type of LED fixture which is particularly more efficient is the troffer. Troffer fixtures are the 2'x2' or 2'x4' recessed fixture found in so many commercial settings. LED lights direct all their output in one direction so that none of the output is wasted. In a lighting fixture such as a troffer that means that the efficiency is even greater than the difference between the basic "bulbs". LED lights have several other advantages over fluorescent fixtures. They do not fade, flicker, or buzz and they can be dimmed. They also operate over a wide temperature range. Unlike both fluorescent and incandescent lights they are not affected by being turned on and off frequently. This means that they are particularly suited to use in commercial freezers with motion sensors. Many grocery stores now use such lighting in frozen food displays.
LED Christmas lights are now becoming common. No fire hazard and replacing burned out bulbs. However, your bubble lights still need incandescent bulbs.
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