Portable Charger

by

Martinna Angelina P. MacaspacMikhael MachaClarissa May M. Ocampo

CHAPTER IINTRODUCTIONA. Background of the StudyIf not all, most of the people today are engaged with new technological advancements that bring us entertainment and relaxation. We can browse the internet, send messages, play different kinds of games, read and view files and other miscellany, all in one handheld device. Because of the frequent use of these gadgets, power is easily consumed, resulting in the reduction of its battery life. Among gadget users, one common problem is reaching low / critical battery level and where to recharge these devices, especially if users are mobile or far from any power outlet / source.A current solution for this problem is the use of power banks, but it also needs to be charged as well. For a power bank to be fully functional, it needs to be fully charged. Also, not all power banks can accommodate all types of gadgets, because the power storage capacity varies with each power bank unit. Sometimes, it provides less than the required power of the gadget. A higher power storage capacity means a more expensive power bank.To lessen the problem, a portable charger is created. The portable charger will use a thermoelectric generator to convert heat into power, which will be stored to the battery. Heat is chosen because it is already present, and it is easily harnessed. Our body produces heat, so there is no need to find other sources. The thermoelectric generator consists of two ceramic tiles placed on top of each other, with conductor seeds placed in between. When one ceramic tile is hotter than the other, the thermopower of the conductor pieces add together to maximize the amount of energy produced. The thermoelectric generator operates based on the Seebeck effect. The Seebeck effect is the conversion of temperature differences into electricity.With this technology, we can recharge our devices without using non-renewable energy, thus conserving energy. Finding a power outlet is not a worry anymore, because this technology runs on body heat.

B. ObjectivesThe main objective of this project is to harness surplus energy from a renewable energy source, specifically body heat. To achieve this, the following procedures are followed: (a) to generate power from body heat using a thermoelectric generator, and by the principles of Seebeck effect, (b) to create a portable battery charger that uses body heat as an energy source, and (c) to charge gadgets and other electronic devices using the generated body heat, (d) and to make charging possible without the availability of electricity outlets.

C. Scope and DelimitationThe device, a portable charger, operates mainly on body heat. The body heat harnessed is converted into electrical energy, which will then be stored in the battery. The portable charger can accommodate smart phones, mobile phones, power banks, and other gadgets. It is also limited to charging only, not as a power supply to other devices.It can be used when gadgets and phones run out of battery. Users just have to attach the portable charger in their bodies using an arm strap or a wrist strap, and connect the charger to the gadget. However, charging time is not instant. Anyone can use this portable charger, as long as they produce body heat.

CHAPTER IIREVIEW OF RELATED LITERATURE AND STUDIESBack in the day, people had to rely on pure muscle power to generate energy. Today, people are now continuing to develop energy systems that do not require full human effort. The evolution of energy development seems to be in sync with the evolution of humans. From human ability, it all evolved into smarter energy sources such as coal, steam, biomass, and renewable sources such as wind, water, solar, and heat. With the continuous growth in sourcing energy, mechanical functions also continue to increase, to meet the unlimited needs of humans. Majority of the energy we get and use are from fossil fuels. Because of this, some energy sources have become scarce, not to mention it slowly harms the environment. With the scarcity of energy sources, researchers and scientists have studied and discovered how to develop energy from alternative sources, which are easily renewable and environment friendly.Energy CrisisToday, there are a lot of ways to produce energy or electricity from different sources. Because as human beings progress, they need to gain more and more energy to satisfy the needs that they require to have a sustainable lifestyle and to be updated to the things that all people are hooked on to. Like us Filipinos, they are fond with new electronic devices, appliances, and many other things that consume electricity in order to work or to be operational. They use it without thinking how much energy they are exhausting to satisfy their craving for fame and to be updated in every event or issue that is present nowadays. Many issues are being discussed in the World Wide Web about the problem concerning on the production of electricity, especially the price and production of electricity in the Philippines. According to the article of Richard Javad Heydarian,power-generating companies to introduce a further hike in electricity prices. To put things into perspective, the Philippines already has Asia's most expensive electricity rates, even higher than post-Fukushima Japan. Such prohibitive rates have not only hurt ordinary consumers, but have also served as among the strongest disincentives against manufacturing investments in the country. [1]Many factors are being blamed, dirty politics, internal demons in the government, bad economy, and other things that affect the production of electricity in the country. Looking at these factors will never solve any problem and will just create more and more issues to be discussed without dealing with the main problem. The article mainly discussed how the price of electricity became the Asia's most expensive electricity rate and how the government acts in the issues that Manila Electric Company (Meralco) will introduce an unprecedented electricity rate hike in three trenches beginning in 2014,[1] added by Heydarian in his article. This news made a public outrage to surface among the Filipinos but President Aquino did not ignore this update from the Meralco and made the agency of the government do their jobs to hold the price hike. But holding the hike is not really the solution, it is just an impermanent aid on the long term problem of the country. Looking at the broader side, the price hike is not the lone problem of the Philippines. There is a predicted energy shortage in the summer of 2015 according to The Philippine Star.[2] The Department of Energy have their precautionary measures but it focused solely on old technologies to produce energy. That is seen in the article of Gonzales:The committed power projects for next year include the 87-MW Burgos wind farm scheduled to commence in February; 150-MW coal plant and 18-MW biomass facility in May; 10.8-MW biomass and 13.2-MW hydropower plant in August; 67.5-MW Pililia Wind in September and a 100-MW Avion plant in October. [2]Using these power plants will increase the energy stock, but did the department contemplate about the bad effects of the non- renewable energy that will be implemented just to ensure the sustainable amount of energy for the Filipinos?Alternative EnergyAt this moment, we have seen that some people are now using alternative energy sources. Solar panels have been installed, and windmills provide energy to some remote areas. However, a big portion of the society still relies on heat energy, because a heat engine has greater power production.A heat engine is an engine that receives heat and converts it into mechanical energy, which is used to do mechanical work that generates electric power. Like energy, heat is also something that can be transferred from one body to another.Steam engines are an early form of heat engine. During its prime, steam engines were commonly used in factories, mills, pumping stations, and mines, as well as trains, ships, and land vehicles. A steam engine has two fundamentals components: the boiler and the steam engine. The boiler, a vessel that contains the water to be boiled into steam, provides the heat to be absorbed by the steam engine. The steam engine converts the steam into work. However, it had its flaws. First, the steam engine has low efficiency, which means that energy is not really utilized to work. Second, it consumes a large space. Notice how large is the first cart of the early trains, as it was entirely occupied by the steam engine. Third, steam engines potentially harm the environment. The burning process produces too much smoke, and could eventually explode due to high pressure.On the other hand, electrical power plants generate electricity through the use of heat engines. In an article written by Quick (2012), he stated that 90 percent of the worlds electricity is generated by heat energy. Unfortunately, electricity generation systems operate at around 30 to 40 percent efficiency, meaning around two thirds of the energy input is lost as waste heat. Despite this, the inefficiency of current thermoelectric materials that can convert waste heat to electricity has meant their commercial use has been limited.[3]Utilization of heat energy is a common practice. In a study conducted by Weisse (2010), he stated that the increasing price of oil, concerts about climate, and the depletion of our natural resources have drawn much attention to renewable energy technology. In 2007, the world consumed roughly 500 quadrillion BTUs of energy and is expected to increase at 1.4% per year. About 90% of this energy was generated through fossil fuel combustion with a typical efficiency of 30-40%. The remaining 60-70% of the energy was lost to the environment via automotive exhaust, industrial processes, and more. It is highly desired to use the wasted heat to improve the overall efficiency of energy conversion. The energy of the wasted heat can be collected and transformed to electricity through a thermoelectric device.[4]Thermoelectric EffectTo begin with, thermoelectricity, or thermoelectric effect, is the direct conversion of heat into electricity, vice versa. A thermoelectric device creates voltage when there is a difference in temperature, or creates a difference in temperature when voltage is applied. The thermoelectric effect of producing electricity from heat is called the Seebeck effect, wherein an electromotive force and consequently, anelectric current is producedin a loop of material. The loop of material is consisted of at least two dissimilar conductors when two junctions are maintained at different temperatures. The conductors are commonly metals, though they need not even be solids.[5] It was discovered by physicist Thomas Seebeck during the 1820s. Thermoelectricity arises when a circuit has two dissimilar conductors or semiconductors that are joined at their ends. When one of the junctions is at a different temperature than the other, a direct electric current will flow in the circuit. For a given thermoelectric circuit operating in a given temperature range, the magnitude of the current depends mainly on the temperature difference between the two junctionin general, the greater the temperature difference, the larger the current.[6] Thermoelectric Generators (TEG)Thermoelectric generators are all solid-state devices that convert heat into electricity. Unlike traditional dynamic heat engines, thermoelectric generators contain no moving parts and are completely silent. Such generators have been used reliably for over 30 years of maintenance-free operation in deep space probes such as the Voyager missions of NASA. But for small applications, thermoelectric can become competitive because they are compact, simple (inexpensive) and scalable. Thermoelectric systems can be easily designed to operate with small heat sources and small temperature differences. Such small generators could be mass produced for use in automotive waste heat recovery or home co-generation of heat and electricity. Thermo electrics have even been miniaturized to harvest body heat for powering a wristwatch. [7]A thermoelectric produces electrical power from heat flow across a temperature gradient. As the heat flows from hot to cold, free charge carriers (electrons or holes) in the material are also driven to the cold end. The resulting voltage (V) is proportional to the temperature difference (T) by the Seebeck effect. By connecting an electron conducting (n-type) and hole conducting (p-type) material in series, a net voltage is produced that can be driven through a load. Many thermoelectric couples need to be connected in series to make the thermoelectric device as shown in Figure 1. [7]

Figure 1For small portable applications, power sources that are smaller and lighter than conventional batteries are of great commercial interest. Even for low thermal-to-electric conversion efficiencies (e.g. a few percent), a small combustor supplying heat to a thermoelectric generator could provide greater energy density than a battery. However, a 10% efficient generator can require at least 500C. In addition, to ensure that the heat is directed through the thermoelectric and not lost in the exhaust, the heat exchangers must be carefully designed. [7]In a study conducted by Kim, We, & Jo (2014), they developed a glass fabric based thermoelectric power generator using a screen printing technique and the self-sustaining structure of a thermoelectric device without the top and bottom substrates. With the technology they used, they were able to create a thin, lightweight, and flexible thermoelectric generator which can be worn. This study can be the grounds for developing new devices such as a self powered wristwatch, or other mobile devices.Environmental ImpactBan Ki-moon is determined to put global warning at the top of the global political agenda and determined to build th trustt so urgently needed if we are to succed in combating climate change. Under his leadership, the UN is credentials by action on the ground and by good housekeeping at home. - Achim Steiner, Executive Director, UNEP Geneva, 117th Assembly of the Inter-Parliamentary Union

A generator can be used as an energy producing unit in it, because it is producing DC or more commonly, AC voltage. Their typical use is to deliver electrical power at places where the main power supply is unstable or non-existent. Such generators may be in operation from a few hours each month to 24 hours a day.Thermoelectric generator is the one kind of generator that we use in making a project. (In research article by Thomas Seebeck, he observed that when heat is transferred between two objects, a current is produced. Since then, electromagnetic field has been harnessed and converted into electricity with the advent of thermoelectric generators.) Thermoelectric generators have a wide range of applications in different fields ranging from household appliances to spacecraft technology. Though thermoelectricity has the potential to greatly impact energy waste, limitations remain in terms of cost and efficiency.The environmental impacts of the thermoelectric generators are particularly useful because they turn a waste product, in the form of heat, into a usable resource in the form of electricity. And these thermoelectric generators are solid-state devices that provide a method for converting the necessary waste product of heat into a reusable energy resource. Heat energy is responsible for almost 90 percent of global electricity production, but the limitations of existing system efficiency results in more than half of that heat energy being wasted as "waste heat." These thermoelectric generators have the potential to reduce the amount of waste heat and, in turn, provide a renewable source of electricity generation. But other generators like the Diesel generators are widely used in many areas where electrical power is unreliable or non-existing. There are generators that are used as a supplement to the main power supply, or as the main power supply as well as emergency backup for hospitals, schools, for computer data-storage, server application that are only used a few extensively as they cause major problems locally, regionally, and on the global plan.

Chapter IIIMETHODOLOGYThis chapter is about the approach used to implement the planned project and to keep the validity and consistency of the study. This part includes the flow chart of the project development, block diagram, testing procedures and evaluation procedures which can help in improving the studys integrity.

Flow Chart of the Project Development The study starts with the research on what topic the proponents would want to focus their research on. The search for possible topics took time and effort before arriving at the present topic. After proposing and making this topic pass, circuitry and other verification methods are needed to verify if this study is feasible with time, money, and effort of the researchers. Proceeding to the next step is another challenge for their resources to produce the components and how to assemble everything that is needed in the circuitry of the device including its strap. The next thing to do is to test and to produce testing parameters to see if the device is accurate and precise in the quantity it gives off. Lastly, if all the given conditions are satisfied, the research is done. The proponents need extra effort to pursue this kind of study because it is a young technology to be used as topic for a research. Only few are able to produce this application of TEG and other organizations / people use TEG on different applications or different conversions of energy.

YESNOYESNO Circuit Simulation and VerificationStartTopic ResearchIf proposed and passed?Pricing and AssemblyIf all conditioned are satisfied?AYESNOA:Testing If working?End

Figure 2Project DesignThe device will solely produce current from the heat of human arm or wrist. This device derived its function from the Seebeck effect, which was previously discussed in Chapter 2 under the topic Thermoelectric Generator (TEG). It is being used in wrist watch according to the article and most likely, the TEG is used to power the watch. But watches are low powered devices, comparing it to the results of this study is irrelevant, but it is still used to power a device that needs current to be operational.In this study, the thermoelectric generator (TEG) is used to charge smartphones or other similar devices. The TEG alone cannot do it but with the help of a DC to DC boost converter, it can achieve a reasonable voltage to charge up batteries from different gadgets and it must be regulated so that every gadget is safe from overvoltage that the TEG can cause. This device is not always placed at the wrist or arm of the user that is why there is battery in the power bank and it is also the initiator of the biasing of the transistor that might be used to produce the boost converter of the device.

Thermoelectric GeneratorBoost Converter and RegulatorBattery

Figure 3

Testing ProcedurePre-testing of components involves carefully examining each component if there are any faults or irregularities that might effect on the progress and the output of the device that needs to be assembled in an ample amount of time for research to have an outcome or prototype per se. It is important on the TEG to be tested before anything else is done, and the output voltage of the TEG must be known to the proponents before the next steps are put into place to ensure the success of this study. Testing the temperature response of the TEG and the assembled device are the next test that must be done to know if it produces the expected voltage to charge up the said gadget. Tabulating the input temperature and the output voltage will help the proponents analyse if the device works perfectly. Evaluation ProceduresThe project will undergo evaluation in order to observe if the objectives of the system were met. Five (5) individuals will be asked to try and test the finished project, and ask them to evaluate it by answering the evaluation form.Each individual will rate the project according to the following factors and ratings:5 Excellent4 Satisfactory3 Very Good2 Good1 FairQuestions:1. Is it accurate and consistent?2. Is it user-friendly?3. How is the quality of the sound?4. How is the quality of the video?5. It is helpful?

REFERENCES[1] Heydarian, Richard Javad (2013, December 23). Philippines Electricity Crisis: How Regulatory Capture Undermines Emerging Markets. Retrieved from http://www.huffingtonpost.com/richard-javad-heydarian/philippines-electricity-crisis_b_4490680.html[2] Gonzales, Iris (2014, July 22). Power crisis looms in 2015. Retrieved from http://www.philstar.com/headlines/2014/07/22/1348931/power-crisis-looms-2015[3] Quick, Darren (2012, September 20). Worlds most efficient thermoelectric material developed. Retrieved from http://www.gizmag.com/most-efficient-thermoelectric-material/24210/[4] Weisse, Jeffrey (2010, October 24). Thermoelectric Generators. Retrieved from http://large.stanford.edu/courses/2010/ph240/weisse1/[5] http://www.britannica.com/EBchecked/topic/532358/Seebeck-effect[6] http://science.howstuffworks.com/thermoelectricity-info.htm[7] Snyder, G. J. Small Thermoelectric Generators. Retrieved from https://www.electrochem.org/dl/interface/fal/fal08/fal08_p54-56.pdf