Design for the Environment/Flashlights

This page is part of the Design for the Environment course

Flashlights are portable, hand held light sources. The company Urban Survival Tools supplies flashlights in their survival kits to be used as emergency light sources.

The three different flashlight design types are compared to determine the most environmentally friendly and economically viable flashlight design type. The three different flashlight design types are: non-rechargeable, or primary battery powered flashlight, dyno torch, and linear generator with supercapacitor flashlight.

A flashlight is essentially an encased power supply which powers a light source. Each of the design types use a Polyethylene casing and white light LED. Therefore, the analysis of the different design types focus on the different power sources of each design.

The non-rechargeable battery powered flashlight uses alkaline manganese battery, Duracell type AA batteries.

The dyno torch converts mechanical energy applied by the user’s hand to electrical energy which powers the light. The dyno torch alternative is hand powered and does not require the use of batteries. The dyno torch is very versatile and reliable and is suitable for emergency conditions.

Linear generator with supercapacitor flashlight is powered by several supercapacitors accompanied by a charging unit. Electric double layer capacitors, commonly known as supercapacitors, are the next generation of capacitors. The electric power creation is accomplished by electromagnetic induction. In the flashlight handle there is a tubular wire coil with a permanent magnet that translates back and forth inducing a current through the wire to be stored in the super capacitor.

The three different flashlights are analyzed to determine which flashlight has the best balance of functionality, environmental impact and economics.

Based on the analysis, it is recommended that Urban Survival Tools use the linear generator with supercapacitor flashlight. The linear generator with supercapacitor flashlight Scores highest on the streamlined life cycle assessment, how comparatively low harmful emissions than the other alternatives and is only slightly more expensive.

Project Information
Section 1 Group A21 Luke Jasudavicius (LJasudavicius) Oxana Kosorukova (Oxana.kosorukova) Sonu Chhibber (Mechysonu) Stephan Kennedy (SKennedy)

Non-rechargeable alkaline manganese batteries
Functional Analysis: General flashlight consumes energy from two alkaline batteries. On average, two Duracell batteries type AA should be replaced every 36 days. These batteries are defined as non-hazardous waste by the Federal Government (US) and can be safely disposed into trash. Recycle of non-rechargeable batteries is somewhat rare and performed during the steel-making process.

Economic Input-Output Life Cycle Assessment: The EIO-LCA used to analyze the non-rechargeable battery powered flashlights provided the following results: Power generation and supply sector, resulted from batteries pre-production and production stages, produce a largest effect on global warming potential. Point air, from factory operation, and non-point air, from truck transportation, plays the most important role in toxic air emissions. Land releases occupy 1630kg from all sectors. Particularly, important pollution metal such as zinc. Coal is the most consumable product for providing energy to manufacturing facilities.

Streamlined Life Cycle Assessment: The qualitative streamlined LCA used to analyze the non-rechargeable battery powered flashlights provided the following results: Overall matrix rating was calculated as 56. Low matrix ratings were given at pre-production and production stages for solid, liquid and gaseous residues, at usage stage for material selection and at disposal stage for solid residues. High matrix ratings were awarded at batteries transportation stage for liquid residues and at usage stage for energy use, solid, liquid and gaseous residues.

Cost Analysis: Total materials cost required for one battery manufacturing is ¢52. Pack of 144 Duracell alkaline batteries, type AA, costs $87.67 with $0.609 for one battery. No cost is required during usage or maintenance. Disposal cost of about 26 drums with alkaline batteries is $5,200. Recycling cost of about 26 drums is $15,600.

Societal Analysis: Primary batteries can discharge at the urgently needed situations and cannot be recharged but replaced only. Truck transportation of batteries releases noise and toxic emissions into the air, contributing to the smog and respiratory problems.

Dyno torch Flashlight
Functional Analysis: The dyno torch is hand powered and does not require the use of batteries. It utilizes more plastic than any other alternative and therefore more environmental impacts associated with the manufacturing and pre-manufacturing of plastic.

Economic Input-Output Life Cycle Assessment: The EIO-LCA used to analyse the dyno torch provided the following results: Large amounts of green houses gases are release in the pre-manufacturing of plastic from the oil extraction and petroleum refinery sectors. Also large amounts green house gases are released from premanufacturing metals from the steel mill sector. A tremendous amount of energy is consumed in the oil extraction and petroleum refinery sectors. the EIOLCA also suggested large Liquid residues are released in the petroleum refinery sectors and large amounts of solid waste in the steel mills sector.

Streamlined Life Cycle Assessment: The qualitative streamlined LCA used to analyze the dyno torch the following results: The stages of life cycle of the dyno torch that causes the most emission and scored the lowest on the SLCA is the pre-manufacturing and manufacturing stage. The usage of virgin petroleum, virgin steel and the significant release of land and water waste contribute such a low SLCA score for manufacturing and pre-manufacturing stage. The emission in the transportation, usage and disposal phase are small in comparison.

Cost Analysis: The unit price to produce and ship one dyno torch flashlight is 95 cents per flashlight.

Societal Analysis: Dyno torch is reliable and suitable for any situation especially emergency ones because of its 'unlimited' power power supply. however the dyno torch must constantly be pressed to generate power and therefore wrist injuries may become a hazard.

Linear generator with supercapacitor flashlight
Functional Analysis: The charging unit will compose of a kinetic energy generator built into the flashlight, which will charge the supercapacitors. Supercapacitors offer many advantages over conventional energy storage devices. They have a very high number of charge-discharge cycles (in the order of millions rather than 200-1000 cycles of a conventional rechargeable battery). For the application of the flashlight, the charge rate may no be consistent; this is one great advantage of the supercapacitor. It can be charged at any rate without degradation, unlike battery that requires a slow constant charge. The energy density and efficiency of the supercapacitor are also both great advantages allowing us to store a lot of energy with little waste. According to ITS (Institute of Transportation Studies, Davis, CA) test results, the specific power of electric double-layer capacitors can exceed 6kW/kg at 95% efficiency orders of magnitude higher that that of battery or conventional capacitors.

Economic Input-Output Life Cycle Assessment: The EIO-LCA used to analyse the linear generator with supercapacitor flashlight battery powered flashlights provided the following results: The power generation and supply create the most greenhouse gas emissions in supercapasitor manufacturing. The largest amount of energy is consumed by the power generation and supply. Ontario's electricity comes largely from coal fueled plants. This accounts for the 1.78 TJ of coal energy used by the sector. A significant amount of energy is also used in the provisioning of the material required for the supercapacitor and generator. The coal and metal mining and processing industries use a large amount of natural gas. The iron and steel mills create the largest amount of toxic releases. It consists mostly of water and land release. The releases come from all the impurities that exist in the iron ore that are removed in the milling process. Sulfur, phosphorous, and excess carbon are the major residues from the milling process.

Streamlined Life Cycle Assessment: The qualitative streamlined LCA used to analyze the non-rechargeable battery powered flashlights provided the following results: The linear generator with supercapacitor alternative has received a streamlined LCA score of 77. All categories given score of four during the entire usage stage of the linear generator because no material is emitted and negligible energy is consumed by the user’s hand. The supercapacitor uses a relatively large amount of activated charcoal compared to its total size. The production of activated charcoal consists firstly of mining the coal, followed by carbonization and oxidation of the coal at very high temperature. This is done to create the large porosity of the material that results in the high energy storage density of the material. This is an energy intensive process. Thus, lows scores are given for the pre-production section.

Cost Analysis: The assembly and the sales of the product would require direct cost as well as resulting indirect costs that may be subject to not only the manufacturing company but other sectors as well. Since a supercapacitor can withstand such high number of charge/discharge cycle and that the flashlight is intended to be used only on occasions, the user will most likely never have any additional cost. Municipal waste disposal for Toronto cost $50.75 per tonne as of 2000. The flashlight will weight approximately 350g thus costing $17.17 per 1000 flashlights discarded. To minimize environmental impact, the flashlight components should be recycled or resold.

Societal Analysis: The supercapacitor is more environmentally friendly than conventional capacitors for several reasons. The smaller size of the supercapacitor allows for less material to be used. The lack of electrochemical reactions reduce eliminate all hazardous waste in the disposal life stage. The supercapacitor is also completely RoHS compliant. The RoHS (Restriction of Hazardous Substances) is a directive to restrict the use of six hazardous commonly used materials in the electronic manufacturing industry. The supercapacitor industry is greatly back by many “green electricity” plans such as the GEL (Green Electricity Initiative).

Recommendation
It is recommended that Urban Survival Tools use the linear generator with supercapacitor flashlight. In the Streamlined LCA comparison, the total scores are as follows: non-rechargeable battery powered flashlight - 56, dyno torch - 72, and linear generator with supercapacitor flashlight - 77. The linear generator with supercapacitor flashlight scored the highest, only slightly higher than the dyno torch mostly due to the additional metals required for the dyno torch. Using EIO-LCA the total global warming potential of each design was found to be: non-rechargeable battery powered flashlight - 582 MTCO2E, dyno torch - 2030 MTCO2E, the linear generator with supercapacitor flashlight - 568 MTCO2E. Using EIO-LCA the total toxic releases of each design was found to be: non-rechargeable battery powered flashlight - 1940 kg, dyno torch - 2150 kg, the linear generator with supercapacitor flashlight - 1950 kg. The linear generator with supercapacitor flashlight has the lowest global warming potential and the second lowest toxic releases, only 10 kg more than the non-rechargeable battery powered flashlight.The linear generator with supercapacitor flashlight only requires to be shaken periodically to be recharged and has a lower mechanical input requirement than the dyno torch. This flashlight has the best functionally for its purpose and it also has the lowest environmental impact. However, it is slightly more expensive. The final cost of a linear generator with supercapacitor flashlight is $3.33 USD, compared to $0.95 for the dyno torch which is the product the current flashlight used in Urban Survival Tools survival kits. But, it is felt that all of the benefits of the linear generator with supercapacitor flashlight outweigh its additional monetary costs.

Non-rechargeable alkaline manganese batteries
Alkaline batteries produce an output voltage of 1.5 Volts and volumetric energy density of 320 Watt-Hours/Litre. It is sufficient for a flashlight to be operated for 6 hours without intermission. These batteries cannot be reused or recharged and therefore must be disposed and replaced by the new ones. There are three active components inside an alkaline manganese battery cell: Anode - contains high purity zinc powder, manufactured to ensure correct particle size and chemical impurity. Cathode – contains powdered manganese dioxide. It is made synthetically by electrolytic process. Graphite is used frequently as an additive to improve electrical conductivity. Electrolyte – alkaline. It contains concentrated aqueous solution of potassium hydroxide. To prevent corrosion of zinc, zinc oxide is added Upon discharge of a battery, the reduction of manganese dioxide leads to the zinc oxidation which is simplified in the following reaction: Zn + 2MnO2 -> ZnO + Mn2O3

The percentages of each composite inside a single battery :

Under test conditions, flashlight power source requires current of 3.9ohms for type AA primary batteries and have on average 6.2 actual service hours.

Metal shelves should be avoided as a storage place for batteries. Storage temperature for batteries has to be maintained between 10°C and 25°C. Relative humidity should not exceed 65%. In order to maximize battery’s shelf life, it should not be stored at the temperature above 25°C. Batteries should be removed from the equipment all the time when it won’t be used for several months. It will prevent possible damage. Replacement of all batteries should be done simultaneously. Mixing batteries, for example alkaline manganese with zinc-carbon should not be practiced as it causes voltage reversal. Recharge of non-rechargeable batteries should never be done, as it creates imbalance inside the cell that results into acid leakage or gassing and possible explosion.

The advantage of non-rechargeable battery is that it does not consume energy while being used. It is safe and easy to use and allowed to be disposed into trash.

The disadvantage of non-rechargeable battery is that it can discharge during unwilling moment without a chance of being recharged. It also produces hazardous wastes during pre-production and production life stages.

Dyno torch Flashlight
Dyno torch does not require the usage of batteries for power. Rather power is generated in the dyno torch by converting mechanical energy to electrical energy where the mechanical energy is produced from the user cyclically pressing down on the crank. Dyno torch is comprised of plastics and metals. The metallic components of the flashlight include copper wires, flywheel, magnet, magnet casing, resistor, spring, pin shafts and screws. The plastic (polyethylene) component of the dyno torch include crank internal, gear rack, internal gears, casing, LED light and lens. Unlike the battery operated or Faraday alternative, the dyno torch’s power source is not storage based (ex. battery or super capacitor).

The advantage of thee dyno torch is that it is hand powered and does not require the use of batteries. The dyno torch is very versatile and reliable and is suitable for emergency conditions.

The disadvantage of the dyno torch is that in order to continuously generate light in the LED like the battery powered alternative; the user must constantly press down on the crank cyclically which can be cumbersome. Another disadvantage is that Dyno torch utilizes more polyethylene (plastic) than the other alternatives as a result of usage of internal gears used to transfer power in the mechanism and therefore cause more emissions as a result of manufacturing process of plastic.

Linear generator with supercapacitor flashlight
Supercapacitors - electric double layer capacitors are the next generation of capacitors. The charging unit will compose of a more conventional kinetic energy generator built into the flashlight. The electric power creation is accomplished by electromagnetic induction. Tubular wire coil with a permanent magnet in a flashlight translates back and forth inducing a current through the wire. The signal is then rectified with a signal diode circuit to create a DC current. The electricity is to be stored in the supercapacitors. Supercapacitor is formed of two collector plates of a common material submersed in an electrolyte solution. The layers are physically separated by a very thin dielectric separator. It is the electrical property of the material known as the electrical double layer principle along with the dielectric separator that allows for the charge separation to occur. Most commonly, supercapacitors use activated charcoal to store the energy due to its porosity thus resulting in an extremely large surface area. Although it is an electrochemical device, there are no chemical reactions occurring to produce energy such as in a conventional battery. The energy is stored electrostatically electrolytic solution.

The advantage of supercapacitor is that it has a very high number of charge-discharge cycles (in the order of millions rather than 200-1000 cycles of a conventional rechargeable battery). For the application of the flashlight, the charge rate may no be consistent; this is one great advantage of the supercapacitor. It can be charged at any rate without degradation, unlike battery that requires a slow constant charge. The energy density and efficiency of the supercapacitor are also both great advantages allowing us to store a lot of energy with little waste. According to ITS (Institute of Transportation Studies, Davis, CA) test results, the specific power of electric double-layer capacitors can exceed 6kW/kg at 95% efficiency orders of magnitude higher that that of battery or conventional capacitors.

The disadvantage of the supercapacitor is that it cannot produce a voltage of more than 2-3 volts. Most electronics operate at low voltage thus solving the problem. In the case where higher potentials are needed, the problem can be circumvented by wiring supercapacitors in series circuits.

Details on Economic Input-Output Life Cycle Assessment
The EIOLCA for the alternatives may be viewed or downloaded

Non-rechargeable alkaline manganese batteries
Power generation and supply is the major sector of battery manufacturing that produces the largest effect, 176 MTCO2E, on global warming potential upon the release of toxic emissions into the air. It is done at the pre-production and production stage of a battery, when materials such as zinc, nickel, alkali, manganese, and carbon are extracted, supplied to the factory and transformed into the useful materials for the manufacturing field. Iron and steel mills, used for steel cans production of batteries, is a second largest sector with great influence on GWP. Truck transportation, caused 43.1MTCO2E of GWP with 42.4MTCO2E of carbon dioxide emmisions, is used for materials and batteries’ shipment, therefore cannot be ignored. When non-rechargeable batteries are used to create 1kWh of energy, the impact on global warming is comparable to driving 457km.

Total toxic releases to the air in primary battery manufacturing process are 18.24kg of emissions. Point air happens during making alkaline manganese dioxide acid from raw materials, steel cans and nickel plates. Non-point air releases produce 10.0 kg of toxic emissions due to the transportation of materials and batteries to the retail stores by trucks.

When non-rechargeable batteries are used to create 1kWh of energy, the impact on air pollution is comparable to driving 2,320km.

The impact on air acidification is comparable to driving 19,812km.

Manufacturing of batteries is an energy intensive process. Mainly, during power generation and supply sector since coal is needed for factory operation to perform paper processing, manganese dioxide formation, steel can punching. Extraction of materials and its supply to the facility consumes energy. Truck transportation of a battery requires fuel and therefore is an energy consuming process.

Dyno torch Flashlight
An custom product EIOLCA was created using the EIOLCA software with the following economic activity distribution $400, 000 for petroleum refinery sector, $400,000 for plastic manufacturing sector, $100,000 for iron and steel mill, $50 000 for steel manufacturing, $40 000 for ferrous manufacturing and finally $10 000 for copper manufacturing.

The phases that release the most emissions throughout the lifecycle of the dyno torch is the premanufacturing (oil extraction and petroleum refining) and manufacturing (plastic resin manufacturing) stage. The sectors that contribute most to green house gas emissions are the oil extraction and petroleum refinery sectors. The GWP (Global warming potential) that oil extraction and petroleum refinery sector release are 353 and 339 MTCO2E respectively. In addition petroleum refinery sector cause a great deal of CO2 emissions (351 MTCO2E) and oil extraction cause large CH4 emissions (282 MTCO2E) Also Large amounts of GWP and CO2 are release pre-manufacturing metal at steel mill sector (both released at 177 MTCO2E).

The largest amount of land and water wastes is produced in the pre-manufacturing stage. The steel mill sector accounts for most of solid and liquid waste releases at 41.1 and 61.6 kg respectively. The petroleum refinery sector that pre-manufactures petroleum to plastic is also a significant source of liquid waste (28.4 kg).

Large energy requirement for a sector indirectly corresponds to large toxic emissions required to generate that energy. The sector that consumes the most energy in the manufacturing of dyno torch is the petroleum refinery sector which requires 6.57 TJ which is significantly higher than the rest of the sectors. The plastic resin manufacturing sector also consumes large amount of energy (3.17 TJ). An interesting observation can be seen from the energy requirement required to manufacture an pre-manufacture dyno torch. It is observed that the main drawback of the dyno torch is that it utilize more plastic than the other alternative and from the EIO-LCA; premanufacturing and manufacturing plastic into product utilizes the most energy inefficient sector (aka petroleum refinery and plastic resin manufacturing).

Linear generator with supercapacitor flashlight
The power generation and supply create the most greenhouse gas emission. due to the energy requirements of the pre-production stage of the supercapacitor life cycle. The emissions from the power generation are mostly CO2 release from coal fueled power stations. In Ontario, there are five coal burning power plants that contribute to the total emissions. The Ontario Power Generation supplies 85% of all power in Ontario and has many initiative progresses that try to minimize the emissions which have led to a reduction of 41% of Nox emission from 1999 to 2004.

The motor and generator manufacturing emit a significant amount of toxic air release due to the amount of metal needed in the production. The energy required and processing of the metal produces a total of 29.4 kg of air release. About 83% of air releases are point. This relatively high percentage of air release is a good thing with regarded to the control and analysis of air emissions. Since the majority of air emissions are stack, they are thus known and can be managed with proper procedure. The iron and steel mills create the largest amount of release. It consists mostly of water and land release. The releases come from all the impurities that exist in the iron ore that are removed in the milling process. Sulfur, phosphorus, and excess carbon are the major residues from the milling process

The largest amount of energy is consumed by the power generation and supply. Ontario's electricity occurs largely from coal fueled plants. It accounts for the 1.78 TJ of coal energy used by the sector. Provisioning of the material required for the supercapacitor and generator uses a significant amount of. The coal and metal mining and processing industries use a large amount of natural gas. The iron ore must be smelted at very high temperature. It requires a large amount of energy taken most commonly from the burning of natural gas. 0.677TJ of energy is required from natural gas to produce the metal components of the flashlight power source. There is possibility to reduce the energy consumption by eliminating the need for metal. The generator casing along with the wire may be replaced with plastic and conductive polymers, although this may not be financially sound.

Non-rechargeable alkaline manganese batteries
Pre-production stage: Solid residues are left during extraction of zinc and nickel.

Product manufacturing stage: Alkaline manganese dioxide, an acid, is used for filling the battery. Paper, zinc, nickel and iron are used inside the specified battery and considered as the materials that cause substantial emissions of toxic, smog-producing or greenhouse gases into the environment. Matrix rating for solid, liquid and gaseous residues in this stage is defined as 1.

Distribution stage: No liquid residues during batteries transportation. Matrix rating for liquid residues sector is given as 4.

Usage stage: Non-rechargeable battery powered flashlight requires its batteries to be replaced periodically. Matrix score of 1 is given for material selection. Battery is a power source; it does not require any energy to operate. Under normal operating conditions battery does not release any solid, liquid and gaseous residues. Matrix rating for energy use, solid, liquid and gaseous residues is given as 4.

Disposal stage: Batteries contain many different solid materials which can not be easily separated. It scores 1 in solid residue. The batteries contain acid, which contribute to its low score in liquid residue.

Dyno torch Flashlight
Pre-production stage: A large amount of energy is consumed to refine virgin petroleum to plastics this SLCA score 1 is given. Refining petroleum to plastics cause large water waste while the usage of plastic is not minimized; a score given score of 1 and can be verified by referring to water emission of petroleum refinery sector in EIOLCA. Solid residues scored 3 due to the minimum usage of metal. Product Manufacturing stage: Manufacturing plastic into desired components produces liquid waste that has not been minimized. Score of 2 is given.

Distribution stage: The components of the dyno torch are small in size and volume. Transportation energy consumption is minimized. A Score of 3 is given.

Usage stage: No material is emitted and negligible energy is consumed from the user’s hand. All categories are given score of 4 during the entire usage stage of the dyno torch.

Disposal stage: The polyethylene components in the dyno torch are recyclable. A score of 4 would have been chosen, but since the dyno torch also contains different kinds of metal components, a conservative score of 3 was chosen instead for solid residue.

Linear generator with supercapacitor flashlight


Pre-production stage: Relatively large amount of activated charcoal is used in supercapacitors compared to its total size. The production of activated charcoal consists firstly of mining the coal, followed by Carbonization and oxidation of the coal at very high temperature.. This is an energy intensive process. Score of 0 is given for the energy use.

Product Manufacturing stage: Production of the components is rather simple and invasive. The material and energy inputs have been minimized as much as possible. The capacitors can use recycled metals as casing. The production of the components produce little residue since the production is in most part a simple assembly process. A score of three is given for this life stage

Distribution stage: The energy of distribution is greatly minimized due to the size of the product. This reduction in size, contributes to a high score in both material and energy. Very little packaging is required and transportation costs are reduced. The material residues are minimized.

Usage stage: No material is emitted and negligible energy is consumed by the user’s hand. Score of 4 is given.

Disposal stage: Components of the linear generator and supercapacitor are distinct and reversibly separable. The linear generator is composed of recyclable metal and rare earth magnet. The supercapacitor's casing is recyclable metal as well as the activated charcoal may be resold or reused since it use in the supercapacitor is not destructive. Activated charcoal is often resold to be used as a component in filters (i.e. charcoal filter).

Non-rechargeable alkaline manganese batteries
Direct Costs: Single alkaline battery weights 23g. Cost of the materials for one battery manufacturing is ¢52.

Supplier’s cost for 144 batteries pack costs $87.67 with $0.609 per battery. Battery does not require any operation costs upon the usage because it is power source and does not consume electricity or materials. There are no maintenance costs, since primary battery is replaced upon discharge only and the flashlight is used in an emergency kit, which means that it will be on rare occasions for the flashlight to be used. At the end of lifetime, batteries are disposed into trash. Disposal of about 26 drums with alkaline batteries costs $5,200. Rare recycling is done during the steel making process and occupies on average $15,600 for 26 drums.

Indirect Costs: Flashlight uses two alkaline batteries at a time. Assuming that a flashlight will be used 10 minutes per day, the user would have to replace two batteries every month.

Dyno torch Flashlight
Direct Costs: The manufacturing cost of the dyno torch includes the cost of pre-production the metal and plastic components of the dyno torch. The cost to run the manufacturing equipment, injection molding machine and extrusion machine used to form the plastic and metal into the dyno torch components (cranks, gears etc.) is also considered. The cost to produce one dyno torch flashlight in China is $0.95. The transportation cost from china to Canada is $9.40 per kg. The weight of each dyno torch is approximately 102.5 gram. Total transportation cost of one dyno torch is $0.9635/flashlight.

No cost at the usage stage as no batteries are required to power flashlight. The disposal cost in Toronto is $50.75 per ton. the cost to dispose of dyno torch is $5.73/1000flashlights.

Linear generator with supercapacitor flashlight
Direct cost: Total direct cost to manufacture one supercapacitor is $3.3259. Conventional capacitors, around 100μF, are sold for $2.29573 opposed to the 1F supercapacitor, sold, for $1.65.

Disposal costs are minimized due to the long life-cycle of the product. When the flashlight life-cycle does come to an end, most likely due to physical damage or lack of need, it will presumably be discarded in normal trash. The waste disposal cost will be incurred by the city. Municipal waste disposal for Toronto cost $50.75 per tonne as of 2000. The flashlight, weighting approximately 350g, costs $17.17 per 1000 flashlights. Flashlight components should be recycled or resold for minimized environmental effects.

Non-rechargeable alkaline manganese batteries
Non-rechargeable alkaline manganese batteries are safe and easy to use. However, discharge of batteries can happen at the unwanted moment. Recommendation for user is to have two extra batteries.

Truck transportation of batteries to the company and retail locations causes a lot of toxic emissions to the air. It causes smoke and may be the cause of respiratory problems.

Dyno torch Flashlight
The dyno torch has a positive affect on society as it is reliable and does not require the use of batteries. It helps users out of emergency situation such as being lost in the woods at night. The dyno torch is the ideal flashlight for emergency lighting situations. One downside that the dyno torch flashlight might have on society is that strain injuries may result in the wrist and arm from continuously pressing down on the crank.

Linear generator with supercapacitor flashlight
The supercapacitor is more environmentally friendly than conventional capacitors. The smaller size of the supercapacitor allows for less material to be used. The lack of electrochemical reactions reduce eliminate all hazardous waste in the disposal life stage. The supercapacitor is completely RoHS compliant. The RoHS (Restriction of Hazardous Substances) is a directive to restrict the use of six hazardous commonly used materials in the electronic manufacturing industry. The supercapacitor industry is greatly back by many “green electricity” plans such as the GEL (Green Electricity Initiative). The technology and efficiency of the supercapacitor is quickly advancing thanks to a large demand and will for more cheap and reliable eco-friendly products.