Executive Summary
The world had experienced much change in the past decades, creating technologies that provide more comfort and freedom to mankind.
In this paper, we will examine human’s dependency on light and the introduction of light bulb to improve their quality of lives. First, we will investigate how light originated and how it will become the necessity of human’s everyday life.
As light technology has been continuously been introduced and improved, new technology such as Light Emitting Diode (LED) will create an impact on the society and will achieve greater heights in the future. The paper will introduce the revolutionary innovation of LED, which seeks to improve the productivity of energy supply, creating a whole new definition of light. This technology will recreate light in the public’s viewpoint both in terms of commercial, and residential with different perspectives.
Introduction and Background
Definition
Light is the electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. As the term suggested, people require light to see and people would be akin to a blind person without light.
Without a doubt, light has become a major part of our everyday lives and people require light to do work. Hence, light bulb is very important as it is able to deliver a constant supply of light during anytime of the day.
Forms of Light
There are many forms of light, and they are evolving throughout the years. The more common forms of light consist of the following:
The first technology of artificial lighting being discovered was Fire during 400000 BC and fire became a source of light for the people in the early centuries. The flaming torch and the campfire enabled human to gain a small degree of freedom from the blindness of night, and some small degree of safety from the fear of unseen prowling creatures. The torch was the first portable lamp and one of the earliest developments was the discovery that a bundle of sticks tied together made a blazing torch, producing a brighter and longer lasting light. With this discovery, human further advanced to control fire and light, leading them to civilization.
Another technology would be candle, which is a solid block of fuel and an embedded wick, lit to provide light and heat. The heat of the match used to light the candle melts and vaporizes a small amount of fuel. Once vaporized, the fuel combines with oxygen in the atmosphere to form a flame and light. This flame provides sufficient heat to keep the candle burning from the top of the mass of solid fuel to the bottom and the flame is diminished once the wax was fully burnt. With technology, different shapes and sizes of candles available in the market for different occasions and uses and provide safe burning technologies.
The improvement in technology enabled the invention of oil lamps in the 18th century and was used to produce light continuously for a period of time using an oil-based fuel source. The fuel source was tightly enclosed in metal and an adjustable metal tube was used to control the intensity of the fuel burning and intensity of the light. Small glass chimneys were added to lamps to both protect the flame and control the flow of air to the flame. Oil lamps were being used until the 20th century, where the technology of light bulb could be used for lighting.
Thomas Edition introduced the incandescent light bulbs in the 1879 which was a major technology invention to the world. The light bulb could be controlled and lit anytime with sufficient power supply, hence giving rise to civilization. The light bulb will be lit when electricity flows through the filament that is inside the bulb and due to the resistance of the filament to the electricity, which increases the filament heat to a high temperature, radiating light on the heated filament. As light bulbs are safer to operate than the other technologies such as fire torch, candle and oil lamps, it became the main choice for the lightings in houses and streets in the 19th century.
Area of Interest
In this paper, we shall narrow our area of interest into the Light Bulbs, in particular the LED light bulbs which brought about revolutionary changes in the society.
Historical Perspective of light bulbs
The earliest light bulb that was invented could be dated back to the 1800s, where Sir Humphry Davy created the first incandescent light. Although the light was not bright enough and didn’t last long, its effort led to the success of the other light inventions over the years. In 1879, Thomas Edison bought over the patent of the light bulb and further invented the technology of incandescent light bulb. Since then, technology has been improving to help mankind invent and improve the quality of lights which are still being used now. These light bulbs are incandescent light bulbs, halogen light bulbs, fluorescent light bulbs and compact fluorescent light bulbs.
Incandescent bulbs work by using electricity to heat a tungsten filament in the bulb until it glows. Most of the energy consumed by the bulb is given off as heat, causing output to be low. Incandescent bulbs produce a steady warm, light that is good for most household applications. A standard incandescent bulb can last for 700-1000 hours, and can be used with a dimmer.
Halogen bulbs are a variation of incandescent bulb technology containing additional halogen gas. The halogen has the advantage of being more efficient and having slightly longer life than the incandescent bulb. They are relatively small in size and are dimmable. The disadvantages are that they are more expensive, and burn at a much higher temperature, which could possibly be a fire hazard in certain areas.
Fluorescent bulbs work by passing a current through a tube filled with argon gas and mercury. This produces ultraviolet radiation that bombards the phosphorous coating causing it to emit light. Bulb life is very long of about 10,000 to 20,000 hours. Fluorescent bulbs are also very efficient, producing very little heat and hence, they are ideal for lighting large areas. With the new type bulbs, and style of fixtures coming out, fluorescents can be used in most places around the home. However, one of the disadvantages is that most fluorescent bulb cannot be used with dimmers. Moreover, fluorescent lamps require the use of electronic ballasts which are more efficient, but cost more to purchase.
Compact Fluorescent Lamps (CFLs) are a modern type of light bulbs that work like fluorescent bulbs, but in a much smaller package. Similar to regular fluorescent bulbs, they produce little heat and are very efficient and normally last up to 10,000 hours. However, most CFLs are dimmer in light quality and cannot be used with dimmers.
Issues, Challenges and Opportunities
Although the introduction of the Compact Fluorescent lamps has many benefits, it is still unable to create a sustainable lighting environment for the world. There are also other flaws of the incandescent and fluorescent light bulb, mainly the high level of heat generation and high energy consumption.
The biggest disadvantage of the light bulb is the heat that is given off by the bulb. On most incandescent light bulbs, 90% of the energy is being wasted through heat while only 10% of the energy is being utilized. This can increase the cost of lighting and it has a negative environmental impact. Currently, there are a few global issues that would affect everyone, which includes rice in the energy consumption, gasoline costs, electric bills, greenhouse gas emissions, dependence on coal and foreign oil and global warming. Human have to deal with all these problems that are arising to build a sustainable environment.
As the current light bulb consumes a lot of energy and due to the limited resources in this planet, scientists have to find solutions such as alternatives and new technology to tackle the shortage of non-renewable energy. Hence, a light bulb with low energy consumption and low heat generation is required to create a sustainable environment for the future generations, which are the LED lightings.
Introduction to LED Lightings
The first known report of a light-emitting solid-state diode was made in 1907 by the British experimenter H. J. Round. However, no practical use was made of the discovery for several decades. The first practical LED was invented by Nick Holonyak, Jr., in 1962 while he was at General Electric Company. They are solid state semiconductor devices which achieves LED illumination when a semiconductor crystal is excited which lead to a direct production of visible light in a desired wavelength range.
The first LEDs which became commercially available in late 1960s were mainly red and commonly used as replacements for incandescent indicators, in seven-segment displays, first in expensive equipment such as laboratory, electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, and even watches. However, these red LEDs were bright enough only for use as indicators, as the light output was not enough to illuminate a small area.
Later, other colors became widely available through the innovative combination of various-coloured LEDs, dramatic colour-changing effects that can be produced from a single fixture through dynamic activation of various sets of LEDs. The increase in the popularity of LED lights was partially due to the development of the white light LED which has the brightest and highest output, through utilization of indium gallium nitride as a semiconductor material.
With the creation of LED white light, LEDs became bright enough to be used for illumination with improved light output and colour rendering capabilities. This resulted in more manufacturers offering a range of LED fixtures for replacing lamps, display lighting, cove lighting, underwater lighting, architectural details and other applications. Currently, there are very few users for the LED light due to its high price, but experts forecast that the LED prices will decline in the next few years and people will replace traditional light bulbs with LEDs. The following table will compare the LED light bulb with incandescent and CFL light bulbs and bringing out the revolutionary change to the lighting industry.
Table 1[1]
Light Emitting Diode | Incandescent Light Bulb | Compact Fluorescent (CFLs) | |
Life Span | 50,000 hours | 1,200 hours | 8,000 hours |
Watts of electricity used (Equivalent to 60Walt Bulb) | 6 to 8 watts | 60 watts | 13 to 15 watts |
Kilowatts Electricity (30 incandescent bulb per year) | 329 kwh/year | 3285 kwh/year | 767 kwh/year |
Annual Operating Cost(30 incandescent bulb per year) | USD$32.85 | USD$328.59 | USD$76.65 |
Contains Toxic Mercury | No | No | Yes. Mercury is very toxic to health and environment |
Carbon Dioxide Emissions | 451 pounds/year | 4,500 pounds/year | 1,051 pounds/year |
Sensitive to low temperature and humidity | No | Some | Yes, may not work under negative 10 degrees or over 1200 degrees farenheit |
Switching on and off quickly may decrease lifespan of bulb | No | No | Yes – can reduce lifespan drastically |
Turns on instantly | Yes | Yes | No – takes time to warm up |
Durability | Very durable, can handle jarring and bumping | Not very durable – glass or filament can break easily | Not very durable as glass can break easily |
Heat Emitted | 3.4 btu’s/hour | 85 btu’s/hour | 30 btu’s/hour |
Failure modes | No typical failure modes | Some | Yes – may catch on fire, smoke, or omit an odour |
Light Output of 1100 Watts with only | 9-13 Watts bulb | 40 Watts Bulb | 18-25 Watts Bulb |
The main features of the LED light bulb that brought about the revolution is the lifespan, energy and power required, less operating cost, safe to use, low carbon dioxide emission, durable and low amount of heat generated. The lifespan of the LED is 50,000 hours, which has increased significantly from the other 2 light bulbs and this would reduce the amount of electricity used to 329 KWH per year, incurring a lower cost of only $32.85. LEDs are also very durable as it can withstand damage better than the other two light bulbs and emits over 9 times less than the other two bulbs. Hence, LED will result in the consumption of less non-renewable energy resources which will improve the environment. Research also shows that widespread adoption of next-generation white LEDs for lighting could, by 2025 reduce electricity consumption by 10 percent worldwide, cutting $100 billion every year from electric bills and saving $50 billion in averted power-plant construction costs. This energy savings would create a huge impact to the society and a step nearer to sustainable development.
Moreover, LED does not contain any toxic materials unlike CFLs, which contains mercury. If human would replace incandescent and CFL light bulbs with LEDs, the carbon dioxide emissions drop by more than half to 451 pounds per year. This could be one of the efforts to reduce greenhouse emissions and global warming and creating a better environment for human to live in.
Discussion and Analysis
With Reference to ‘Guns, Germs and Steel (Vintage 2005)’ by Jared Diamond, this paper would also talk about the application of the theory of Necessity as a Mother of invention to the technology of the LED.
Inventions are mother to necessities
Firstly, it states that technology is cumulative, rather than isolated invention and most people will find the uses only after the technology is invented, rather than invented to meet a demand. This is similar to LED, where some people are already quite satisfied with the current lightings and do not foresee a need for such technology. After LED has been introduced, people then realize the benefits and will start to shift towards a better technology product.
Secondly, it states that inventions supposedly arise when there is an unfulfilled need in the society. This could be the invention of light, where people realize that there is a need for light so that they could carry out activities anytime of the day. However, there are also other views where technologies are invented not for any demand. Some people only discover the uses of the product after its invention has succeeded or after they used the product of technology for a period of time. For instance, people do not realize that they need an apple I Phone before it has been introduced, but when it has been introduced with all its smart functions, it has become a necessity for almost everyone. With the example from ‘Guns Germs and Steel (Vintage 2005)’, motor vehicles were being introduced without the purpose of satisfying a need but was gaining popularity since then and has become a need for those in the urban environment. Similarly, the public is generally satisfied with the currently available technology of incandescent light bulbs and CFLs with the exception of scientists and environmentalists which may deem that there is a need for such technology which will then be linked back to the theory of Necessity’s mother. However, once LED was being introduced with their enormous energy savings and more environmental-friendly effects, people start to use LED and will reckon that there is a need for themselves and the environment to use LED lights. Hence, this is a very good example of having the invention without a need to satisfy initially.
In ‘Guns, Germs and Steel (Vintage 2005)’, it also talks about the factors that actually influence acceptance of people. Basically, all the factors that influence acceptance are the benefits that LED bring to mankind. People are often swayed by the good things they see in the technology and that the product will help them in one way or another. Moreover, people tend to compare the new product with the existing products to weigh the costs to get them and the benefits of using them. For LED, there are many advantages over the other light bulbs which will influence people into accepting and adopting the new technology.
With its technology advancement and improvement, LED lighting is on the edge of becoming the lighting method of choice and surpassing the market dominance that Edison’s invention has held for so long since 1879. The U.S. Department of Energy (DOE) predicts that within 10 years, LEDs will overtake incandescent light bulbs to become the main light source in residential lighting applications because of the advantages that LEDs have over the incandescent bulb which will be explained in detail below.
Advantages and Disadvantages of LED
LEDs offer many benefits such as small size, long lamp life, low heat output, energy savings, durability, instant lighting, ease of dimming, silent operation, little Ultraviolet emissions and increased safety with low-voltage power supply. All these advantages will help to reduce energy consumption, reduce usage of resources for replacement, and reduce environmental damage which will ultimately lead to a sustainable environment for the future.
LEDs are highly efficient, being six times greater than incandescent bulbs. In traffic signal lights, a strong market for LEDs exist as with the red signal operating about 50% of the day, the complete traffic signal unit is estimated to save 35-40% of energy. It is estimated that replacing incandescent lamps in all of America’s some 260,000 traffic signals could reduce energy consumption by nearly 2.5 billion kWh. At the end of 1997, more than 150,000 signals were retrofitted, almost all of them red. LEDs produce efficacies greater than incandescent lamps and rivalling fluorescent lamps.
Besides being extremely energy-efficient, LEDs are also very durable which could be normally used for 50,000 hours while some could even reach100000 hours, about 20 years time. Hence, LEDs are ideal for hard-to-reach or maintain fixtures such as exit sign lighting and, pathway lighting and cathedral ceilings. LED products currently make up about 50% of the exit sign market and a study conducted by the Lighting Research Centre in 1998 found that LEDs were being utilized about 80% of new exit signs in the United States.
LEDs could also be used for art exhibitions or shops as preliminary research suggests that using coloured LED background lighting combined with spot lighting on merchandise may improve energy efficiency and reduce maintenance costs while catching the eye of the consumer in a fresh manner. LEDs produce no UV radiation and little heat, making them ideal for illuminating objects, such as works of art that are sensitive to UV light. A prime early-adopter application for LED white light is in museum or retail settings where light needs to be trained on a specific area. Since LEDs do not emit UV or infrared radiation, there is no concern of damaging sensitive paintings and fabrics. Hence, many people uses LED lighting, with the additional benefit of being able to precisely set the color temperature to best highlight the item on display. One of the key attributes of LED is that it doesn’t emit a lot of heat. Hence, this product can be hard-wired into new construction or retrofitted into a given structure.
However, there are also imperfections of LED lights. One disadvantage is that a single LED is very small and produces little light but can be combined in any shape due to their small size. In addition, LEDs can be considered miniature light fixtures where the distribution of light can be controlled by the LEDs’ epoxy lens to selectively dim individual LEDs, resulting in the dynamic control of distribution, light output and colour. Some companies also utilize unique feedback technology to keep the colour temperature of the light consistent.
With a traditional bulb, light is generated by the glowing filament, creating heat which generally wastes 90 percent of the electricity. While LEDs are more efficient, the heat they generate stays inside the semiconductor and must be extracted and dissipated to prevent the LED from overheating and failing. Hence, other research must be done to improve the thermal traits.
Autocatalytic Process
The light bulb also uses the autocatalytic process mentioned in the ‘Guns, Germs and Steel (Vintage 2005)’, where technology advances based upon previous discoveries. It attributes the autocatalysis to the previous mastery of simpler problems, new technologies and materials available that enabled the generation of other new technologies by recombination.
It applies to the invention of light as well because Thomas Edison was not the one who invented the light bulb but instead, he patented the work of Henry Woodward and Matthew Evans. However, he eventually built upon this technology and invented the element of long lasting filament for the light bulb to work and last. LED light has been discovered in 1907 and the first practical use was in 1967, but it took quite some time to research and develop into the LED now which has a lot of advantages over the other light bulbs due to its limitations in the past. This could also prove the effect that people built upon the previous technologies and combine with new features to make LED better.
Some cities who are trying to attain sustainability seek to reduce environment costs as one of their goals, in which natural resources is one of them. LED has created a huge impact on the environment by saving energy which no other lighting devices or technology has been able to do so.
Taking Things Forward
Although the current LED light bulb has brought to human higher energy savings and more sustainable environment, there is still room for improvement of the LED in the future to create a better lighting technology to head towards sustainability. Recognizing the importance of LEDs in the greater energy-efficiency scheme, the DOE is actively focusing resources on the research and development of solid-state lighting products in an effort to speed up this process. In my opinion, some of the technologies that may contribute to the future of light could be Solar-powered LED, Organic LED or even bio-LED from plants.
Solar-Powered LED
The solar powered LED was another technology that may become the solution for the lack of resources in the future. These LEDs are very efficient and energy saving as they just need 10 percent of the traditional lights, and they can run for about five years without maintenance.
OLEDs
The current research shows that Organic light-emitting diodes (OLEDs) have the greatest possibility to be the next emerging technology that is still in the laboratory. If it can be made practical, it may create more extreme impacts than LEDs or even replace LEDs as an energy-efficient alternative for general lighting in the future.
OLEDs are similar to electroluminescent lighting, in which a sheet of material is excited and emits light. An OLED light source is a thin, flexible sheet of material consisting of three layers, a polymer or sublimed molecular film sandwiched between two layers of electrodes. With one of them being transparent, light will be emitted through its transparent layer when current passes through the material. Mass production of these products could be as simple as ink-jet printing because there is no need for the costly chi-fabrication facilities that make LRDs so expensive. Hence, it will most probably be the technology that replaces LEDs. The main impetus for OLED development is coming from companies that seek backlighting for cheaper, brighter displays.
The manager of the light energy conversion program at GE Global Research also showed a 15 by 15cm prototype which has double the efficiency of OLED. Particles are also added to the OLED substrate to provide more changes for the light to zip from the surface rather than being absorbed by the device. This technology could make OLED-based white lights competitive with fluorescent tubes within a decade.
Unfortunately, such efforts to provide higher efficacies will in turn produce too much heat and reduce the life of the light source. Many renowned manufacturers are all currently working on ways to develop the commercial OLED products.
Lighting designers often try to integrate lighting hardware and architecture in a cohesive manner, but with OLEDs the architecture may be the lighting hardware itself. Sheets of material can be integrated with building materials such as wood, glass and other materials, converting them into luminous surfaces.
Lastly, based on current lumen packages and the great potential for this light source to be adopted for more general lighting applications, the next step is for the fixture community to begin building more products designed to utilize LEDs as the primary or supplementary light source.
Conclusion
Light technology has come so far from the discovery of light, to the invention of light bulb and the advancement into LED. The invention of the LED that could solve all the problems may seem far-fetched, but with the rate of advancement in technology, anything is possible. In our current technology stage, it isn’t difficult to enable the technology of LED light to be the main electronic light chosen by people in the future. The introduction of the LED light has brought about a lot of advantages to human which has existed due to constant research and testing. We have to be very innovative and persevere in our research with beliefs just like Thomas Edison, who was highly motivated and finally succeeded only after the 100th tries of the light bulb.
As technology has been moving very fast, people have to be capable and maintain a different viewpoint from the general public. Therefore, we need people like Sir Humphry and Thomas Edison who could be able to think untraditionally to create more ideas for the society as innovators are usually people who think out of the box to reach creativity.
The introduction of a revolutionary technology will always bring about competition for a better product which is beneficial to mankind. More competition means more effort to create a better technology to impress people as well as bring more impact to the people and environment. Hence, the LED light would definitely constantly be reviewed and tested with new components to improve and provide a better lighting technology for the society. Comparing the LED light that has been created to the other better light bulbs such as incandescent light bulbs, CFLs, LED light has brought about revolutionary changes to the environment and people would definitely try to improve on the current LED to increase efficiency and reduce cost.
In conclusion to this paper, the creation of a better light device will not seem to be easy, but with the current forecast and development of ideas, it would definitely come to light in the future as light is a very important necessity to human. As Kurt Cobain once said, “The sun is gone, but I have a light.”
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