Engineering Commons^™

Insulated Solar Electric Cooker With Phase Change Thermal Storage Medium, Justin Brett Unger, Nathan Robert Christler, Matthew Weeman, Marcus Edward Strutz

Mechanical Engineering

This final design review document outlines the senior design project carried out by a team of four mechanical engineering students at the California Polytechnic State University – San Luis Obispo under the sponsorship of Dr. Peter Schwartz of the Cal Poly Physics department. The aim of this project was to improve upon the design of previously developed Insulated Solar Electric Cookers (ISECs) by adding a thermal storage system to allow for quicker cook times and the ability to cook food at non-peak solar hours. The team’s goal was to develop a working prototype utilizing a phase change medium as the …

Vaccine Cooler For The Global Poor, Benjamin J. Larson, Cooper E. Gibson, Eilbron Younan, Cody R. Volk

Mechanical Engineering

Cal Poly physics professors Peter Schwartz and Nathan Heston approached the Solar Freeze team with the problem that remote communities in Africa have limited access to modern-day medicine or vaccines. They suggested that we try and design a cooling device that can keep vaccines cold for multiple days at a time while the medicine is transported to remote villages. Currently, there are vaccine cooler products on the market, but most of them are very expensive or lack portability. Peter and Nate have tasked the Solar Freeze team to come up with a less expensive solution that is also portable and …

Ares Cleaning System, Andy Sagers, John Cunningham, Peter Greig, Jack Glynn

Mechanical Engineering

In this Final Design Review, the team outlines the general scope of the ARES Cleaning System project and the final design direction chosen and built. This team consists of a group of four mechanical engineering students who have been tasked with designing and manufacturing an autonomous ARES cleaning system to help their sponsor, Fracsun, better track soiling losses measured at large solar arrays. They designed, conceptualized, manufactured, and tested throughout the project as they looked to create a final, functioning product. In creating this Final Design Review, they have identified how the product will perform the desired functions and what …

Solar Irradiance Microforecasting, Austin Jeffrey Fite, Sara Naseem Kipps

Computer Engineering

In late winter quarter 2018 the University of New Mexico and Microgrid Labs provided the Cal Poly Electrical Engineering department with their prototype Solar Irradiance Microforecasting (SIMF) hardware. This hardware was provided to the University under the lone condition that data collected with it would be returned to Microgrid Labs to train their weather model. The goal of this senior project was to take the provided hardware and software and make it usable for students in the Cal Poly Electrical and Computer Engineering departments to hack and expand. The end goal with the hardware is near term cloud and weather …

Grid-Tied Solar System, Virginia Yan

Electrical Engineering

Distribution level solar energy generation has gained importance and popularity, because it helps create a sustainable electricity system while reducing the harmful environmental impacts our current power systems have. This project proposes an alternative energy source, a laboratory-scale grid-connected photovoltaic system. A KC120-1 solar panel produces 120 Watts maximum. A grid-tied solar power inverter does DC-to-AC conversion and minimizes energy transfer losses. The inverter also has an anti-islanding feature, which senses a power outage and prevents back-feeding through isolating the circuit. The circuit breakers isolate electrical components and protect the circuit. Schweitzer Engineering Laboratories SEL-751 feeder protection relay and SEL-735 …

Solar Cell Potential Induced Degradation Sensor, Luc Alexandre Tousignant

Materials Engineering

It is important to maintain Photovoltaic (PV) cells and protect them from damage mechanisms like Potential Induced Degradation (PID), which can contribute to shorter lifespans and lower efficiencies. Current leakage through cell encapsulation can cause charge migration in PV cells that reduces the maximum quantum efficiency, which is the cause of PID. An experiment was setup to determine the feasibility of a non-silicon sensor able to produce similar leakage behavior to traditional PV cells under recorded humidity conditions. Thin sheet metals were encapsulated in EVA, a common PV encapsulant polymer, and mounted in aluminum framing. Three sensors, along with a …

Dc House Solar Panel Cleaner, Sarahanne Heredia, Sophia Deguia

Electrical Engineering

Solar panels lose 0.05% of their power conversion efficiency per day due to soil accumulation, according to an experiment conducted by the University of California, San Diego in 2013 [18]. The project is an electro-mechanical cleaning system that effectively and efficiently cleans solar panels at set intervals. A drip irrigation system with spray jets was attached to a water pump and Arduino, both powered by the DC House Project solar panel battery. The DC House solar panel was the targeted panel set up for the project. Several components of the design could have been chosen more optimally for the system; …

Development Of An Insulated Solar Electric Cooker (Isec) With Thermal Storage For Use In Developing World Countries, Amanda Gyokery, Spencer W. Davis, Kyle Henry Smit

Mechanical Engineering

According to the World Health Organization, about half of the world’s population uses biomass stoves to cook their meals. However, biomass fires can be dangerous. Unattended biomass fires and indoor air pollution are responsible for an estimated 600,000 deaths annually and the creation of approximately 4 million instances of chronic disease. They also release CO2 and other pollutants into the air, and require the families to gather enough material to keep it burning (WHO 2017). Although cleaner cooking technology seems like a clear solution, often families are either unwilling to change how they cook food or are unable to afford …

Dc-To-Dc Buck Converter, Kyle Christopher Roman

Electrical Engineering

The growth of sustainable energy requires many components to work in harmony creating one efficient and effective system. Sustainable energy generation that produces a DC current varying in voltage requires a subsystem to convert voltage to a practical and usable value. The DC to DC Buck converter converts high DC solar generated voltage to a 12V output. This Modular -Level power electronic (MLPE) device performs as a solar charge controller for small lithium ion batteries. Fluctuating voltage levels generated by Photovoltaic cells makes the solar controller a critical part of the solar system. Regulating the DC voltage allows safe and …

Medium Duty Gas-Turbine Engine Blade Removal Tool, Elliott James Greb, Jacob Thomas Syage, Kellen Thomas Field

Mechanical Engineering

Solar Turbines Incorporated sponsored a team of three Cal Poly Undergraduate Mechanical Engineering students to design, manufacture, prototype, and test a tool for the removal of turbine blades from their respective disk assembly without damaging the disk itself. The tool was developed for Solar’s industrial gas turbine engines. The tool complies with all OSHA and Solar Turbines safety and engineering constraints, and was designed for use in a shop facility. The tool was made adaptable for geometric variances in multiple turbine rotor disk stages, and requires no more than one technician to operate using a maximum of two shop resources. …

Solar Powered Single-Axis Heliostat Active Solar Tracking Device, Mason Kyle Roberts

Physics

As a means of cooking food, the burning of biomass accounts for over 4 million premature deaths in third world countries (“Household Air Pollution and Health”). The focus of this project was to explore an alternative that could utilize focused sunlight to cook food. A solar tracker was designed to be affixed to a parabolic, reflective, tilted single axis heliostat to follow the sun throughout the day and focus the reflected light to the bottom of a cooking surface. This surface became hot enough to for the preparation of food or boiling/sterilization of water.

A goal for each project was …

Solar Roller - Solar Powered Usb Charging Station, Aaron Bartfeld, Tanner Mjelde, Kaylan Naicker

Electrical Engineering

As the necessity for renewable energy increases, solar power becomes more and more prevalent. At the same time, as technology increases, the necessity for charging one’s electronic devices also increases. The Solar Roller merges solar energy with the ability to charge one's electronic device in one compact cart. The Solar Roller is a solar-powered USB charging station that allows people of all backgrounds to develop a better understanding of alternative fuels, while charging their USB device. It has a touch screen display that provides voltage levels of the battery as well as a TV that displays solar powered information. The …

Dc House Energy Management System, Zachary L. Eldredge, Zoe M. Hay

Electrical Engineering

In this work, a previously completed proof of concept for an Energy Management System (EMS) for the DC House project has been revised and re-implemented. The implemented design changes will improve the performance and reproducibility of the system. This new design of the EMS replaces the two-separate buck and boost DC-DC converters with a single bidirectional DC-DC converter to reduce components and improve efficiency. Analysis of the bidirectional DC-DC converter shows high efficiency especially at larger load currents. The code of the previous work was updated for smoother operation as well as to accommodate an LCD capable of displaying more …

Solar Powered Electric Vehicle Charger, Jessica A. Bombardier Shaw, Andrew F. Moradpour

Electrical Engineering

This project will look into how to create an efficiently-operated solar powered electric vehicle charger. The solar panel will harvest energy from the sun that will be stored a battery pack to be readily available to charge an electric vehicle. These stations could be commercialized to be located along a highway, or personalized for a in-house installation.

Photovoltaic Cooking In The Developing World, Tyler Watkins, Christopher O'Day, Omar Arriaga

Mechanical Engineering

The challenge of clean cooking is faced by hundreds of millions of people worldwide. We present a cooking technology consisting of a solar panel directly connected to an electric heater in a well-insulated chamber. Assuming continued decrease in solar panel prices, we anticipate that in a few decades Solar Electric Cooking technologies will be the most common cooking technology for the poor. Appropriate use of insulation reduces the power demand making low-power Insulated Solar Electric Cooking systems already cost competitive.

Solar Car Suspension System, Alex Power, Adam O'Camb

Mechanical Engineering

No abstract provided.

Photovoltaic Installation In Ecuador And The Amazon, David Mulder

Construction Management

The Photovoltaic Installation in Ecuador and The Amazon is part of a collaborative effort between two major construction clubs at Cal Poly: NECA and MCAA. Four students, two from each club, traveled with two faculty to install photovoltaics for two different communities. The first project was a solar installation to provide fresh water for the community of Santa Rosa. Project number two, was a sixteen-panel installation in Shell, Ecuador for the non-profit Reach Beyond. The main goals of each project were to provide fresh water, and achieve net zero electrical consumption.

Fluid Analysis In Solar Heat Pipes, Ben Krumholz, Michael Agavo, William Dundon

Mechanical Engineering

Evacuated tube solar collectors are efficient systems that use heat pipes to facilitate heat transfer. They use incoming solar radiation to heat water. Professor Mason Medizade tasked the team with choosing a component of the system to research and test its influence on system performance. The team investigated the working fluid that runs through the heat pipes. Distilled water, acetone, and ethanol at a range of fill volumes form 1 mL to 11 mL were tested. The team's goal was to find a volume for each fluid to maximize performance of the system. Performance was defined as average temperature rise …

Solar Generation's Impact On Fault Current, Kody Heppner

Electrical Engineering

California is paving the road for other states with the capacity of solar installations for residential and commercial entities. The added capacity of solar generation to the state's electric grid has an impact on power flow and fault currents. This project looks at the impact of solar installations on fault currents. Feeders with added residential rooftop solar and larger commercial solar installations may impact the system differently than a large, utility-sized solar installation. This project looks at the impact of both cases on the magnitude of fault current during many different fault types and locations that can occur within a …

Solar-Powered Hot Tub, Jonathan Peterson, Anthony Zepeda

Electrical Engineering

This paper discusses the design and implementation of a solar-powered hot tub. The concept of this project was to design an independently-operated hot tub powered by a 12V rechargeable battery, charged during the day by a single 400W solar panel. For this purpose, a twenty-year-old name-brand hot tub was purchased, in used condition. The plumbing, AC electrical wiring, and mechanical pumps were all removed and replaced with new components to meet our design specifications. Additionally, a solar water-heater was designed and integrated into the system to directly apply the sun’s heat to water pumped in and out of the tub, …

Automated Solar-Powered Chicken Coop Door, Brenna Yagade

Computer Engineering

The purpose of this project was to plan, design, and build an automated, low power system to open and close a chicken-coop door, which is powered through a solar panel.

Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook

Materials Engineering

The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …

Solar Decathlon Instrumentation And Controls, Timothy Ambrose, Mateo Begue, Andrew Elliott

Mechanical Engineering

The Instrumentation and Controls team has designed a control and instrumentation system for the 2015 Cal Poly Solar Decathlon house that will monitor temperature, humidity, and energy usage throughout the house and control the phase change material duct. It will relay information to the user through a tablet application developed by the Computer Science team. The team has also designed a lighting control scheme for use with Lutron’s HomeWorks QS lighting control system.

Smart Solar Oven, Aaron Gragg

Computer Engineering

Though solar oven technology provides a green and cost effective means of cooking, it is often not adopted because it fails to meet the demands of speed and reliability that are commonplace in our society. This project explores the modification of a traditional box solar to meet these demands by allowing the oven to report temperature to a user’s phone as well as orient itself towards the sun throughout the day.

Transimpedance Amplifier For Polymer Photodiodes, Sheridan Knighton

Electrical Engineering

Dr. Braun’s students in the Polymer Electronics Lab currently have a way to measure the light intensity from their light emitting devices however it consumes an unnecessary amount of space and power. I offer to improve upon the existing transimpedance circuit that Dr. Braun currently uses, reducing the total space occupied by the circuit and the power consumption of the current setup. The transimpedance circuit measures the incidence light intensity from the polymer-based photo detector and outputs an accurate, discrete, and measurable voltage. The current setup however utilizes two 20V wall warts for the positive and negative rails of the …

Analysis And Optimization Of The Scheffler Solar Concentrator, Simone Alberti

Master's Theses

The Scheffler reflector is a new solar concentrator design which maintains a fixed focus while only having a single axis tracking mechanism. This design makes the construction and operation of high temperature solar concentrators accessible to developing nations. In this project, I wrote computer simulation codes to better understand the dynamics and the effect of deformation or deviations from ideal conditions in order to define necessary manufacturing and operational tolerances. These tools and knowledge drove the prototyping of new reflector concepts by myself and other students on my team. A fiberglass prototype was able to drive the cost of a …

All Purpose Mobile Gps, James C. Smith, Matt Weege, Kevin Peters

Electrical Engineering

The aim of the All Purpose Mobile GPS (The System) is to create a GPS tracking device that can accurately record location and calculate velocity, distance traveled and elevation change even when the satellite signal is lost. This data can later overlay on existing internet-based maps illustrating a trip to oneself or others. The portable tracker consumes very little power achieving several days’ worth of power in a single charge. A solar cell provides a quick battery boost in a pinch. SD Card storage increases compatibility with computers and other forms of data transfer. Data processing, such as viewing the …

Bike Safe: An Automatic Turn Signal System, Betty He Chan, Ricardo Alberto Duran

Electrical Engineering

Bicycles are vehicles that do not require a license to operate and share the road with cars, motorcycles, and other fast moving vehicles. An improper lane change from a bicyclist, such as one without any warning, can lead to great injury or death (especially after sundown). Bike Safe addresses this safety concern by providing a low-cost device that mimics the warning system motorists’ use every day. The system consists of a red brake light and amber turning signal lights that mounts to the rear of the bike, as well as a white headlamp that mounts to the front handlebars. The …

Investigation Into The Mitigation Of The Effects Of Uncertain Optical Degradation On An Interplanetary Solar Sail Mission Using A Single Model Update, Jordan Smiroldo

Master's Theses

The renewed academic interest in using solar sails as a source of spacecraft propulsion has been accompanied by a recent fervor of investigations into non-ideal and off-nominal sail performance considerations. One of the most influential considerations, uncertain optical degradation, has been shown to present significant trajectory design difficulties. This paper investigates the potential of using a mid-course degradation model update to mitigate the risk of missing the target destination in a sample 300 day Earth-Venus trajectory. Using a range of potential degradation profiles, it is shown that correcting in the first half of the mission is highly likely to result …

Bluelock: A Secure Bluetooth Operated Padlock, Trever Mckee

Computer Engineering

For this project a secure, battery operated, Bluetooth operated padlock was created. The project included both the hardware to integrate with a padlock and an Android application used to interface with the hardware. In order to make the padlock secure both AES encryption and challenge response authentication were used for secure message passing between the device and the Android phone. The project also included power consumption and sustainability tuning including exploring Arduino sleep states and integrating the project with a solar charging unit.