January 26, 2015 Dr. Andrew Rawicz School of Engineering Science Simon Fraser University Burnaby, British Columbia V5A 1S6 RE: ENSC 440 Capstone Project Proposal for the Stellar Dish Sun-tracking Solar Cooker Dear Dr. Rawicz, Attached is a proposal for Stellar Dish Sun tracking Solar Cooker. Our purpose is to design and build a working Solar Cooker using an umbrella that will be rotated automatically to track the sun using an arduino microcontroller. By tracking the sun, the cooker will be able to harness approximately 25% more solar power. This proposal will provide an introduction to our apparatus and highlight on the benefits and risks of solar cooking. A section will be included to discuss the current solar power market and the solar power industry which will give insight on the business prospects of this field. It will also include a budget section describing what components we think will be needed. Sun Crest Inc. is comprised of four dedicated and fully-committed 4th-year engineering students: Owen Au, Tenzin Sherpa, Monica Santiago, and Imtiaz Charania. We are all motivated to design and deliver the best possible product to our clients and believe in turning idealities into reality one step at a time. If you have any questions or comments please feel free to contact at me msantiag@sfu.ca. Sincerely, Monica Santiago CEO, Sun Crest Inc. Enclosure: Proposal for Stellar Dish Sun-tracking Solar Cooker
Proposal for Stellar Dish: Sun-tracking Solar Cooker Project Team: Phur Tenzin Sherpa Monica Santiago Owen Au Imtiaz Charania Contact Person: Monica Santiago msantiag@sfu.ca Submitted To: Dr. Andrew Rawicz ENSC 440 Steve Whitmore ENSC 305 School of Engineering Science Simon Fraser University Issued date: January 26, 2015 Revision: 1.1
Executive Summary Cooking is a fundamental element of everyday life. But many developing countries do not have access to modern heat sources and are still cooking with firewood. Using firewood is not only environmentally unfriendly but the resulting smoke is known to cause health problems such as cataracts after repeated, prolonged exposure. We propose to alleviate this problem by harnessing the power of the sun. Most existing, conventional solar cookers on the market are expensive. They use relatively inaccessible materials such as fiber glass, can weigh as much as 4.5kg and require periodic manual repositioning throughout the day. In this document we present a proposal to pursue the development of a solar cooker which addresses these issues. The solar collector of our solar cooker will be made of lightweight, yet sturdy umbrella coated aluminum foil. To tackle the repositioning problem, we aim to design a reliable, yet inexpensive mechanism which will automatically direct the cooker towards the sun throughout the day to maximize amount of sunlight collected. The time frame for the development of our solar cooker is 10 weeks. This period will be divided into 5 main phases: Research, Design, Module Building, Module Integration, and Testing each lasting 1-3 weeks. The tentative cost for this project is $755. Sun Crest Inc. consists of four enthusiastic fourth-year engineering students hailing from electronics, systems and computer engineering concentrations. We are confident that our innate drive to solve problems, combined with our knowledge of electronics, physics, and embedded software will enable us to make this project a success. i
Table of Contents Executive Summary... i List of Figures... ii List of Tables... ii 1. Introduction... 1 2. Proposed Solution... 2 2.1 System Overview... 2 2.2 Solar concentrator... 2 2.3 Sun-Tracking Mechanism... 3 2.4 Potential risks... 3 3. Market Analysis... 4 3.1 Competition... 4 3.2 Research Rationale... 5 4. Budget... 6 5. Schedule... 7 6. The Team... 8 7. Conclusions... 9 8. References... 10 List of Figures Figure 1: Stellar Dish High Level Diagram... 2 Figure 2: Solar-Tracking Control Flow Chart... 3 Figure 3: Gantt Chart showing Milestones and Dates and Durations of Key Tasks... 7 Figure 4 Major Milestones and Deadlines... 7 List of Tables Table 1: Equipment List and Breakdown of Expenditures... 6 ii
1. Introduction I d put my money on solar energy. I hope we don t have to wait till oil and coal runs out before we tackle that -- Thomas Edison, 1931. The goal of this project is to design a system to harness solar energy as clean, renewable, inexpensive and effective alternative to firewood as a heat source for cooking. Our target audience are people living in developing areas of countries which have mostly dry, sunny climates and limited-to-no access to electricity. Firewood has been used for thousands of years as a fuel source for heat required to cook food. 2.6 billion [people] rely on firewood for cooking and heating [1] Although it is tried and true it is not without its drawbacks. Obtaining firewood is excessively time consuming. Women and children must wake up at very early to gather firewood if they do not have enough money to buy it. Women and children who must gather firewood often live in places of political unrest, making the seemingly simple task of gathering firewood a dangerous one. Furthermore, as a result, children often miss school. Since firewood is so difficult to obtain it is often rationed. This discourages them from cooking nutritious foods such as beans, which may require more wood to cook. Fire itself has health and safety risks as well. If the fire is open, as in a traditional campfire, there are risks of it getting out of control, or of children accidentally getting burned. If the fire is contained in an oven (which often does not have a smokestack) the effluent smoke has nowhere to go but toward the user, causing eye, skin and lung problems after repeated, prolonged exposure. The use of firewood also impacts the environment as the resulting smoke releases harmful gasses into the atmosphere. And, perhaps most obviously, the use of firewood requires cutting down trees. Cutting down trees for warmth and shelter may not have been a problem in the past, but with today s increasing rate of deforestation, every little bit helps. 1
2. Proposed Solution 2.1 System Overview Our system will use a reflective umbrella serving as a solar concentrator which will amplify the heat generated such that it can be used to cook. This purpose lends itself into pasteurization of water to provide safe drinking water into rural communities. To optimize the heat generated, the collector will be able to automatically move such that it is facing the sun at all times throughout the day, much like a sunflower. Figure 1: Stellar Dish High Level Diagram 2.2 Solar concentrator From the concept of basic high school physics we all remember (or at least have heard of) setting ants on fire. We are essentially implementing the same concept except to serve a greater humanitarian purpose. Electromagnetic waves (sun rays) bounce off of a parabolic reflective surface causing them to concentrate at one unique point known as the focal point. In this project we plan to use an umbrella covered with aluminum foil to reduce cost. 2
2.3 Sun-Tracking Mechanism We will attach 23 solar cells to the umbrella to generate a total of 60 watts (11 Volts). These cells will be used to power the motor and serve as a light sensor. As indicated in figure 2 below, we will use the measured intensity/ voltage as an input into the micro-controller. This input from the solar cell will be fed into the microcontroller as a source of power and intensity at different angles will be compared to determine how much the dish should be rotated. Additionally, if the sun is blocked by clouds, the micro controller will activate an auxiliary power source such as a battery. Figure 2: Solar-Tracking Control Flow Chart 2.4 Potential risks The main concern that this project entails is the potential for things to catch fire if the heat is not controlled. In one case study, similar designs of parabolic solar cookers were implemented in Altiplano, Bolivia as an alternative to limited firewood. Their solar cookers were placed near their shed causing it to catch fire. In this case, the reflected Electromagnetic Radiation (EMR) was converged to a point; however in non-ideal cases it has spatial extent [2]. This non-ideal case is in our favor as the heat will be evenly distributed over the cooking surface. 3
3. Market Analysis According to research conducted by Michael Grupp at Synopsis, there is a potential for a $1.8 billion annual market for solar cookers. His research also states that 50% of families throughout the world (approximately 333,000,000 families) would buy a solar cooker and save up to 60% of what is being spent on fuel [3]. In terms of market demand, there are several other advantages to solar cooking than just boiling and cooking. Advantages include [3]: Preserving nutrients in food Saving the cost of fuel for other purposes such as school and health Use in potential business such as extracting wax from honey and sanitization of medical instruments 3.1 Competition Throughout the years, there has been a lot of development in creating solar cookers. At present, there are several different kinds available on the market. Some examples include: box-style, panel-style and parabolic. Some of the important features of competing North American companies are stated below. All American Sun : A Solar powered box cooker constructed using fiberglass, raises temperatures up to 300 degrees Fahrenheit. SolSource: This company designs a parabolic solar cooker weighing 4.5 kg and provides a cooking temperature of 750 degrees Fahrenheit All Season Solar Cooker: Cookers produced by this company are parabolic with adjustable reflectors to achieve wide range of temperature. Hot Pot: Reflective layer of the parabolic dish is made from aluminum, providing a temperature of 250 degrees Fahrenheit [4]. All these products are designed to serve different purposes, such as high temperature, varying temperatures and so forth. These products have various advantages yet some disadvantages. At SunCrest Inc. our focus is to create a cost effective solar cooker which solves some of the most common issues with the product present in market. 4
3.2 Research Rationale There are several solar powered cookers available in the market with different features, design and specifications making it difficult for our company to come up with a solution that is different yet helpful to our target audience. After thorough research and brainstorming, the most common disadvantage our team encountered was solar tracking. For maximum reflectivity, the position of the dish has to be changed with respect to the position of the sun, which can be annoying. Our team at Sun Crest Inc. aim to resolve this problem designing an electromechanical system attached to the dish which will help in tracking the sun and moving the apparatus without any manual effort. 5
4. Budget The table below gives a rough estimate for the budget needed to develop the early prototype of our project. It factors in shipping costs for online orders as well as equipment already in our possession. Please note that our list of equipment is subjected to change as we refine the implementation of the project and added costs may apply. To cover the potential added costs, we have included a miscellaneous costs section. Unfortunately we have not received any updates from the ESSEF on how much funding our group will be given at the time of this written proposal. The bulk of our budget is allocated to purchasing the mechanical components controlled by the Arduino Microcontroller which will be incorporated into rotating the sun tracking mechanism. We also plan to put either photo sensors or solar cells evenly around the umbrella as a method of measuring the light intensity at various places on the umbrella. Table 1: Equipment List and Breakdown of Expenditures Item Estimated Cost Arduino Microcontroller $0 Umbrella $30 Stepper Motors, Gears, and Actuators $375 Photo Sensors/Solar Cells $100 Support Structure $100 Power Supply/Batteries $100 Miscellaneous $50 TOTAL $755 6
5. Schedule The following Gantt Chart shown in figure 3 shows the projected start, duration and completion dates for the major phases of this project. They have been scheduled largely around the due dates of the functional and design specifications as well as the wait period for ordered parts. The Modules referred to in the figure are: the solar concentrator, the sun-tracking mechanism, and the support structure for both the dish and the cook pot. A breakdown of the major deadlines and milestones is shown in figure 4. Figure 3: Gantt Chart showing Milestones and Dates and Durations of Key Tasks Figure 4 Major Milestones and Deadlines 7
6. The Team Monica Santiago, Chief Executive Officer (CEO) Monica is a fifth-year computer engineering student. She will be serving a project manager and will be involved with the programming of the sun-tracking mechanism. She has completed two co-ops with BlackBerry as an Audio Engineering Associate where she performed audio tests on handheld devices and wrote documentation for testing processes. She served as project manager of a team of four for an iphone application development project for a software development course. She has also had over four years of experience using electronics lab equipment. Owen Au, Chief Financial Officer (CFO) Owen is a fourth-year electronic engineering student. He will be programming with microcontroller as well as designing breadboard circuits as components of the overall sun-tracking system. He is experienced in designing and working with circuit designing and hardware programming FPGAs. In addition, he is an avid learner of tcp/ip networking routing and is extremely tech-savvy when it comes to routers. He has led a team of 3 people in designing a FPGA guitar device for a digital design course. Phur Tenzin Sherpa, Chief Operational Officer (COO) Tenzin is a fourth year electronics engineering student in Simon Fraser University (SFU) Canada. His primary interests are Electromagnetic theory and its applications in communication systems. His skills include conceptualizing real- world problems and proposing a solutions besides the technical engineering skill set. He has been one of active member of the company and has fully contributed into the design of the sun-tracking mechanism as well as the solar collector. Imitaz Charania, Chief Technology Officer (CTO) Imtiaz is a fourth year Systems Engineering Student at Simon Fraser University. The courses he has taken equip him with both hardware and software skills. He has programming experience in C/C++, JAVA, Assembly language, MATLAB and VHDL which can assist the company in successfully building the project. He also has knowledge about engineering Mechanics, programming sensors and building electromechanical systems and can use software such as SolidWorks, AutoCad and CNC machine programming. With skills in computers, electronics and mechanics makes Imtiaz the best person to assist with the mechanical component of this electromechanical device. He is the company's CTO. 8
7. Conclusions Our team at Sun Crest Inc. aims to design clean, reliable, effective and affordable cooking device for developing countries. Primitive heat sources such as firewood impose health issues such as cancer and cataracts. Modern heat sources require electricity and present solar cookers are also expensive and require repositioning. Our design incorporates solutions to these problems by harnessing solar power more efficiently with our sun tracking system. The initial design will involve optimizing the use of the light focused by the solar concentrators; devising the best support structure for our solar cooking apparatus; exploring options for the power supply and auxiliary power, and developing a high-level blueprint for the sun tracking system. To accomplish these tasks, two members will work on the physics aspects and computations related to the design of the solar collector. The other 2 members will work on the implementation of the sun tracking system. After about 1 month we will combine the two sections. What separates us from our competitors is our ability to integrate available electrical and mechanical technologies to develop this product with inexpensive materials. A product that will not only be used to cook without generating smoke, serious risk of burning or fear of running out of fuel, but also requires limited human effort, while saving time and money. 9
8. References [1] "Uk to help girls and women access clean energy," [Online]. Available: https://www.gov.uk/government/news/uk-to-help-girls-and-women-access-clean-energy. [2] "Wikipedia: Focus (optics)," [Online]. Available: http://en.wikipedia.org/wiki/focus_(optics). [3] "Solar Cooking," [Online]. Available: solarcooking.org. [4] "Solar Cooking Wiki," [Online]. Available: solarcooking.wikia.org. 10