DES 40A A03 - Fall 2018
Life Cycle of a Flashlight
Professor Christina Cogdell
DES 40A A03
6 December 2018
Life Cycle of an LED Flashlight - Materials
The rush of the holiday shopping season is here yet again, with thousands of people flocking into stores, prying to get their hands on the latest smartphone or laptop. Yet, in this mad frenzy of purchases and credit card swipes, not one of them questions the true repercussions of this now routine behavior. Recent technological developments in today’s society have contributed to a shared mindset of consumerism in which a large number of goods are produced and purchased without ample consideration. The general public neglects to recognize the consequences of how they were manufactured, and what will become of them when they are no longer useful.
Although new and advanced innovations roam the market today, even the most basic of devices can reveal how complex the manufacturing process is, for example, the flashlight. Being one of the most widely owned electric appliances, it is often taken for granted. However, a comprehensive analysis of its production process will aid in illustrating that even seemingly simple technology is assembled through a wide variety of materials that become detrimental to the environment when extracted and processed on an industrial scale. Let us begin by investigating the most essential component of the flashlight: metal.
Beginning with the bulb itself, LEDs are composed of diodes which are made up of semiconductors with impurities. These semiconductors are typically gallium-based, more specifically, gallium arsenide (GaAs). Although found in trace amounts in minerals and ores, the majority of it is produced as a byproduct of mining other metals like aluminum in bauxite ore and zinc in mineral sphalerite. The other component of the LED are the wires which are often made up of gold and chlorine compounds like gold trichloride (AuCl3) and chloroauric acid tetrahydrate (HAuCl4). These can be found free in nature and are often associated with quartz, pyrite, and other minerals.
In addition to the LED bulb, the flashlight houses a system of metal springs or strips that connect the electrical components of the flashlight together. These are called “contacts” and are usually made from copper, which can be found in many parts of the world, primarily in the form of copper ore. The United States is the 2nd largest producer of copper globally, with the largest mine located in Bingham Canyon in Utah.
With such a heavy reliance on metal as an electrically conductive material, it is necessary to understand the ramifications of the mining process. Mining is a common practice for extracting and refining metals, and while it is necessary to create much of the technology that exists today, it also has its share of negative environmental impacts. Mining requires heavy machinery to dig vast craters in the earth’s crust, producing large pits and sediments of waste rock. These fine mineral particles are capable of polluting water sources in a process called siltation. This sediment, along with dangerous chemicals used onsite, like mercury and arsenic, contaminate the water, which can affect irrigation, fisheries, and clean water supply. In addition to water pollution, mining also worsens air quality. The inevitable removal of soil causes the particles to become airborne due to vehicle traffic and wind erosion. These air particles are harmful to humans and have been linked to causing respiratory illness such as emphysema. Finally, the mining process is destructive to land and biodiversity. Because of the extreme changes in terrain, ecosystems are heavily impacted. Not only does it damage natural habitats, it can also alter local temperature and pH levels, which has the potential to partially or completely eradicate entire species. Though mining is a useful method for obtaining material, it is also incredibly dangerous and influential in terms of the environment and those that inhabit it. This, however, only addresses the metal components of the flashlight; the exterior components that encase them are of equal significance.
Unlike the electrical items, the exterior pieces are generally composed of various plastics and polymers that are altered through chemical processes. Most plastic flashlights use acrylonitrile butadiene styrene (ABS), a durable thermoplastic commonly used in industrial products. The reason ABS is used so often in product design is that it has a strong resistance to corrosive chemicals and is physically strong, making it a long-lasting option. It also has a low melting point, making it easy to manufacture through injection molding, and is a relatively inexpensive material. The polymer is made up of three monomers: acrylonitrile, butadiene, and styrene, all of which are modified composites of natural gas and petroleum.
Outside of the flashlight itself, is another important plastic that is used to package the item. This is called high-density polyethylene (HDPE) and is the most widely-used type of plastic in the world. Due to its light yet strong and durable properties, it is one of the most versatile and common plastics for packaging store-bought goods. This is also made up of petroleum, which is then put under intense heat in a process called “cracking” until it forms polyethylene where it can be molded into a specific shape.
The plastic refinement process, much like mining, involves balancing the benefits of the purified materials with the environmental issues that arise in their formation. Both ABS and HDPE are children of two nonrenewable fossil fuels, natural gas and oil. These sources of energy are formed from the dead remains of ancient marine life that have been subject to high pressure and high temperatures. They are extracted using drilling methods in which giant machines drill beneath the land and ocean floor to bring them to the surface. Throughout this process, however, the water that is trapped below is also brought to the surface and can carry dangerous concentrations of heavy metals, hydrocarbons, and radioactive material which are harmful and difficult to dispose of in a safe manner. This is especially a concern when hydraulic fracturing methods are used because of the large scale of water and chemicals used, many of which have been found to cause cancer and other severe health conditions. Above the surface, even more troubles arise. Drilling wells are known to produce high amounts of methane, a powerful greenhouse gas, much more potent than carbon dioxide. These emissions contribute towards global warming by trapping heat inside of earth’s atmosphere, and this progressive increase in temperatures opens up countless more issues related to extreme weather events, public health, sea level rise, and many more. Additionally, fossil fuels are a large cause for air pollution when they are burned during the manufacturing process. An example of this is nitrogen oxide, which increases smog levels that can cause chronic respiratory diseases like asthma and bronchitis. It is also linked to acid rain which can contaminate lakes and other water sources and tamper with the safety of ecosystems. These cases clearly testify to the fact that plastics are no less innocent than metals in how they affect the environment in their extraction and refinement methods. Yet, even after all of the chemical and mechanical processes are complete, and the parts have been fully assembled and transported to store shelves, the life cycle of the product and its materials continue to unfold.
Now that the flashlight is in use, it becomes an everyday object; however, the materials that comprise the device will remain an influential factor, as it affects the environment after disposal. Upon reaching the consumer, the product will finally serve its purpose for many years to come. Fortunately, LED lights are generally long-lasting over many years; batteries, however, are not. Although it is dependent on the type of battery, the average one consists of cadmium, lead, mercury, nickel, lithium and electrolytes. Because the majority of customers do not think twice before throwing used batteries in the trash, many of them end up in landfill. Over time the casing of the outer shell corrodes, allowing the chemicals inside to absorb into the soil. This can pollute water supply and even reach the ocean where marine life can be impacted. In addition, chemicals like cadmium, nickel, and lead, that are found in batteries, are human carcinogens that have been known to cause health threats upon close contact. Furthermore, lithium has been known to cause landfill fires that send toxic fumes into the air, making it even more likely to reach people and cause illness. The other components of the flashlight are actually, for the most part, reusable. The problem is not whether or not it is recyclable, but whether or not consumers will choose to do so. This simply comes down to society’s awareness of the world’s current state and the importance of recycling. Ignorance and disregard of this evidence will lead only to greater landfill and pollution. Although steps have been taken to bring attention to this crisis, there is no question that this is the result of excessive manufacturing and consumerism.
Society has now reached a point where the consequences of large-scale industrial production are beginning to negatively impact the environment physically, chemically, and biologically. By examining the life cycle of just one simple product, it is evident how much energy and material resources are necessary to manufacture them in large quantities. Ecosystems and natural habitats are being destroyed. Air and water that were once clean are being polluted. Waste emissions from chemical processes are accelerating global warming. Even humans, themselves, are risking their own health. Flashlights are only one small example in a sea of innovations and products that are made by the millions every day, and it is crucial to understand and acknowledge this as we consider the future of industrial and product design. In striving to preserve the environment, it is important to be mindful of what and how we choose to produce goods. If we continue on this road of selfishness and gluttony, we will, at some point, reach a point of no return.
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6 December 2018
LED Flashlight Embodied Energy
Flashlights are a common tool used by many people, yet few know very much about the energy that goes into their production and lifecycle. This paper investigates the energy used in making aluminum-bodied lithium-ion flashlights, from the mining of metals through manufacture of the flashlight body and the batteries, then shipping to consumers, and finally which parts are recycled and which are placed in landfills. The life cycle of the flashlight consumes a great deal more energy than most people realize, which is detrimental to the health of the environment.
First, the beginning of the life cycle of a flashlight is the extraction of the raw materials and the shipment of those materials to the processing plants, both of which consume a lot more energy than most consumers know. The body of the flashlight is made from aluminum, which in its raw form is bauxite ore. During the extraction, bauxite ore is mined from the earth using petroleum-powered mining equipment such as bulldozers. This is a large energy expenditure due to the use of fossil fuels, which affects the environment negatively; in addition, mining typically disrupts local environments through disruption of the soil and destruction of habitats. In bauxite ore mining, explosives are often used to loosen the ground before mining equipment goes over it, which is of course very destructive to the local ecology (“Aluminum Mining and Processing: Everything You Need to Know.”). Bauxite ore is then shipped to the processing plant; shipping is another massive expenditure of energy. Another part of the flashlight, the LED, requires a wide variety of metals, such as “arsenic, gallium, indium, and the rare-earth elements (REEs) cerium, europium, gadolinium, lanthanum, terbium, and yttrium” to be mined, typically as byproducts from aluminum, copper, lead, and zinc mining (Wilburn). Mining itself is very energy intensive as it uses explosives to loosen the ground and mining equipment is powered by fossil fuels, and then these rare earth metals must be processed in order to retrieve them from the waste while mining bauxite. It also has a lot of consequences for the environment, since mining equipment tends to run on internal combustion engines, and ripping up the earth tends to affect animal habitats negatively. A third crucial part of the flashlight comes from the batteries. A common type of battery used is lithium-ion batteries. The lithium is mined in a simple process; there is brine with a high concentration of lithium carbonate, and the water is evaporated out. Then the lithium carbonate is separated from the other miscellaneous contents and can be processed for use in batteries. After these processes, the raw materials are shipped to wherever the processing plant is, which is a massive energy expenditure in itself. For example, a big ship can use 110 tons of fuel oil per day, and crossing the Pacific Ocean can take up to two weeks. As this fuel oil is burned, it releases greenhouse gases into the atmosphere, and permanently decreases our supply of fossil fuels.
Next, the parts must be manufactured, another significant energy expenditure. Once more, this impacts the environment negatively. At the plant, bauxite ore is refined into alumina, which is then heat baked in order to produce aluminum (US DOE LED source). Heat baking is less energy intensive than some of the other processes involved, since producing heat is more efficient than producing electricity. Then the aluminum is typically machined into the shape of the flashlight body and reflector (the shiny part around the light which makes the light brighter), since aluminum is relatively soft and easy to machine. Typical machines for that type of work such as mills and lathes run on electricity, which is a significant energy cost since eight billion kWh was consumed in mechanical engineering operations during 2010 (Rajemi), and most electricity in the US is produced using fossil fuels. Furthermore, in LED manufacture, the machines that produce LEDs are run on electricity (Szypszak). Once more, most of the electricity in the U.S. is generated through coal power plants, so the energy and environmental cost of running these machines on electricity is actually quite high. After the flashlight is produced, it then must be shipped to stores where the consumer can buy it. The locations of manufacture and purchase vary depending on the company. One example is the Surefire company, which manufactures flashlights in Fountain Valley, California. Shipping a Surefire flashlight from Fountain Valley to Davis, CA would not consume as much flashlight as shipping it to New York, for example. Thus, a consumer looking to minimize embodied energy should always try to buy from local companies if possible. Overall, the manufacture of the flashlight is one of the most energy intensive stages.
Then, the flashlights are bought by consumers and used. This is the least energy intensive aspect of the flashlight’s life, since LEDs are very low energy use and flashlights are typically only used at night. Batteries, such as lithium-ion batteries, power the LEDs that produce light. The chemical energy from lithium-ion batteries is converted into electrical energy, which then generates light and heat. LEDs use very little energy compared to their main competitors, incandescent lights. A typical LED light uses ten watts per hour, compared to a fluorescent light bulb, which may use up to sixty watts per hour. This means that flashlights do not use very much energy while in use. Thus, since LED flashlights use very little energy comparatively, the use of the flashlight uses the least amount of energy, even though it is what most consumers think of when they consider their energy consumption.
Finally, the flashlight breaks down in some way, such as the LED wearing out. Depending on the consumer and their location, the flashlight is either thrown in the trash, to be taken to the landfill, or it may be put in an electronics recycling program. At the landfill, the flashlight may be incinerated, or it may be placed in a sanitary landfill - sanitary because it has to be sealed, otherwise toxic metals leak out into the environment. However, the batteries should be recycled, and the aluminum body may be recycled also. Many areas have battery recycling programs; for example, the city of Davis has a recycling program that takes batteries for free. They are collected and the materials are separated out for reuse as much as possible. The collection of these batteries takes a fair amount of energy (driving around collecting recycling, shipping the used batteries to a plant for reprocessing), but it is better than incineration or the landfill because there is less pollution and less wasted space respectively. In other words, recycling is more energy intensive than placing the flashlight in a landfill, but there are high environmental benefits to reusing the materials. Unfortunately, not all metals can be recycled, and even when metals can be recycled, they may not be due to the higher cost of acquiring recycled metal (such as lithium for a lithium-ion battery) rather than simply mining the metal in easy to find natural deposits. It is easy for consumers to think of disposal as the end of the flashlight or battery’s life, but with recycling it becomes a cycle where the materials can be reused, as opposed to discarding them forever.
Overall, there are many different stages of the life cycle of a flashlight where energy is consumed, much more than most consumers know. This use of energy impacts the environment, since the petroleum used in mining pollutes the air. Some parts of the manufacturing process use electricity, which is most often produced in coal power plants - these also pollute the air, making flashlight production detrimental for the environment. Although flashlights are useful, consumers should remember the three R’s: reduce, reuse, recycle. For example, when the flashlight breaks, it is likely cheaper and better for the environment to try to fix the broken part, rather than discarding the flashlight and buying a new one.
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