Good Thesis Proposal On Motivation

Abstract

There are different types of energy harvesting systems that are creating high motivation among engineers to develop the systems that can contribute in making the environment clean and livable. Solar energy is one of the most critical energy sources used for producing different energy systems. Nowadays, solar energy is widely being used to lit the buildings and operate other electrical appliances. This project is aimed at analyzing and designing a solar energy harvesting electrical system to be used for the lightening the bulb and to operate other minor electric appliances in the house. The paper will discuss the equipment to be used in designing the harvesting system, define the electricity and solar energy terms, timeline, and finally make risk assessment related to the project.

Introduction

Energy harvesting is the process in which a little amount of energy is collected from the natural energy sources and stored for later use. There are energy harvesting devices that effectively and efficiently accumulate, capture, store, and supply in a form that can be used for the useful purposes like it may provide energy to light up house or light bulbs, or supply energy to the electronic devices like control circuitry or sensors for intermittent duty applications. Energy harvesting systems may also be used as an alternative source of energy to enhance the overall system reliability, supplement primary power source, and prevent power interruptions .

Energy harvesting systems have triggered great motivation among the engineering communities to develop different applications that use energy harvesting technology for power. Technical institutes are conducting research to improve efficiency of devices to capture energy from environment and transform them into electrical energy. Additionally, the researchers are making advancements in microprocessor technology to increase power efficiency, and effectively reduce power consumption requirements. The system of energy harvesting has already been deployed in various real life applications like wireless sensor network systems like ZigBee systems, and electrical energy power supply.
The common natural sources like solar energy, mechanical energy, and wind energy are used to produce energy by means of energy harvesting system. Mechanical energy can be collected through the sources like mechanical stress, strain, and vibration; thermal energy through sources like heaters, furnaces, friction, and heaters. Similarly, light energy can be generated through solar energy, or photo diodes, photo sensors, or solar panels. Other sources of energy includes, water flow, wind, ocean currents, biological, and chemical sources. This study will focus on the solar energy to harvest electrical energy for lighting the bulb at house.

Objectives

In this study, first the basic terms of electrical and solar energy harvesting system will be defined and discussed. Progressively, the study will move towards the requirements and design of the solar harvesting system. For purpose of designing this project, the timeline will be prepared by breaking down the activities of the complete project. These basic objectives or small tasks will help labors to understand and get an idea of the exact time limit. Thus, it will be easier for the manager to complete the project in time.

Significance

Solar energy can be used for several purposes like to heat up buildings or homes using different solar systems like solar space heating, solar hot water systems, and electrical generation or photo voltaic (PV). The solar energy can be of great help for the environment in the upcoming days of energy crises. Water, oil, coal, and others are finite natural resources that would end up one day; however, sunlight is among those natural resources from which we can take many benefits without worrying about depletion .

Proposed Approach

In order to design the solar energy harvesting electrical system, there needs to review the requirements of both the design of the solar system and the electrical energy requirements of the house. First, the electrical system and the demands of the household electrical appliances and then the solar system equipment that would be used in the design will be discussed.
The common electrical systems terms used in the solar energy harvesting system are AC/DC, electrical load, load, amperage, watts, energy usage, and phantom loads. These are defined as follows,
AC/DC termed as alternating current/direct current. Photovoltaic solar cells generate DC electric current; however, most of the household appliances use AC current to operate. For this purpose, it is important to convert the direct current that was generated through solar system into alternating current. The primary difference between the direct and the alternating current is the direction of the current. The direct current flows in one direction; however, the alternating current flows in opposite direction after every few intervals. To implement the solar energy harvesting electrical system for the house, the inverter would be fixed at the output of direct current that would convert it into alternating current.
Electrical load – it is electricity or energy consuming appliances that demands for the electrical system. Like in case of the house building solar energy electrical system, the bulbs and other illuminating devices are the electrical loads.

Voltage (V) – It is the pressure that makes electrons flow through the wire

Amperage (A or I) – it is also termed as amperes which is the unit of electrical current and is usually denoted as A. In case of the house building electrical system, the amperes would be the current required for lighting the bulb or other illuminating devices.
Watts (W) – It is the unit of power measuring the electricity produced or used. The voltage and current combines to give watt or power.
Energy usage – the number or amount of watts used in the given time is expressed as watt per hour. In case of this project, the electrical demands can be expressed as the watts per hour used by any electrical appliance like the one a 60-watt bulb is lit for 4 hours in a day, so the energy usage of the bulb would be 240 watts-hour. The total energy usage in the house is calculated by measuring the watts per hour consumed by each device and then summing them all.

Design Approach

As discussed earlier, photovoltaic solar panels are designed to convert solar radiation into direct current or DC electricity. PV conversion is implemented in a way that provides highest power density to energy harvesting module. It makes the sun energy harvesting system as one of the best choices to generate energy using a small harvesting module. The solar energy harvesting system although consumes a lot of energy in units of megawatts but requires only a small sized equipment to convert sunlight into electrical energy. It uses energy storage elements like batteries, and ultra-capacitors that have large range of voltage current characteristics. The primary element of the solar harvesting system are the solar panels that catches sunlight energy and convert solar radiations or insolation into direct current electricity or DC. Insolation is expressed in terms of watts per square meter of units. The insolation is higher if the sunlight is bright. On a clear day, usually the insolation is measured to be about 1,000 watts per square meter. Similarly, the peak sun hours can also be measured by determining the insolation. Since, the peak hours of sun vary from area to area, season-to-season, atmospheric conditions, and even earth’s position. Therefore, it is important to deploy the system as according to the environmental conditions and location .
There are number of solar panels installed in the photovoltaic solar systems that are wired together called as array. Solar panels provide energy to the battery bank that makes storage of the power and supply it when solar energy is not available that is at night. In addition to solar panels, the photovoltaic system includes, electrical disconnects, inverter, overcurrent protection, junction box, circuit breakers, fuses, and specialized equipment. These elements are chosen based on the type of application like battery-backup, off-grid, and grid tied. This solar energy harvesting system has to be designed for the home or small building; therefore, off-grid design will be implemented.
In an off-grid design of the solar energy harvesting system, a battery bank is sealed in a box that keep it secure from battery acid spills, or gas escape from the battery. The charge controller controls the battery bank that prevents battery from over-charging and low voltage cut-off. It occurs when a battery tries to operate on low charging that shortens the battery life. The lead-acid and alkaline batteries will be used in a PV solar system. Lead-acid batteries are usually designed to control the frequent discharging and charging; therefore, these batteries are especially used for the household electrical systems.
For an off-grid system, the user has to provide complete demands and autonomy for an electrical system; therefore, to design this system, first, the inventory for electrical loads and demands will be collected. Even the simple and minor acts related to the solar energy system are documented before designing the harvesting system. For example, starting the microwave or turning on light switch, and for how long the electricity will be used in a day or even a week, accounts for the specific design of the electrical system. Similarly, in this case of designing the solar harvesting system for the house, the user must document all the electrical demands so that all load estimations, and electrical loads can be made .

Block Diagram

Figure 1: Solar System Harvesting Electrical Energy System

Software Requirements

Making choice of the right appliances and equipment is very important, since it also affects the budget of the project. There are certain appliances that are capable of saving much energy as compared to other devices with the same performance like in case of energy savers and florescent bulbs. Similarly, battery bank, and wire sizing affects the performance and budget of the solar energy harvesting system. Considering these factors, it is important to choose the design that is most cost efficient, but at the same time provide performance up to the level. There are not as such large number of software programs used in the design of solar energy harvesting system; however, the microcontrollers used in the system require programming. Therefore, the process and input will be stored in the controller so that appropriate actions are performed are automatically when the input is triggered like sunlight sensor gets active and perform the actions as directed in the software program.

Timeline

The following tasks will be performed while designing the solar system harvesting electrical energy for the house building.
Analysis of the weather and location
Assess the suitability of the source of energy for the specific location
Estimate the electrical demands and electric load
Determine the appropriate tools and equipment to be used for the solar system.
Place an order for the equipment used in the solar energy system project.
The project proposal timeline is given as follows,
Risk Assessment
Conclusion
The solar energy harvesting electrical systems are the need of the time; since, most of the naturally occurring energy resources like water, oil, and coal are finite and may end up in the next 50 years. These natural resources are among the basic needs of all living beings; therefore, they must be restored and used for only basic living requirements. The solar energy that is free and unlimited can be used for electrical requirements so that other resources can be stored in reserve. The solar system design analyzed and proposed in this paper can be efficiently deployed; however, there needs to make accurate measurements of environment, location, and equipment so that an exact design can be made. The risks related to the solar system must also be considered so that any unforeseen situations can be professional tackled.

References

Davidson, Joseph and Changki Mo. "Recent Advances in Energy Harvesting Technologies for Structural Health Monitoring Applications." Hindawi Publishing Corporation (2014). Online.
Jones, K. Harvesting Energy from the Sun: Solar Photovoltaics . 10 2009. Online.
Kazmierski, Tom and Steve Bobby. Energy Harvesting Systems. 2011. Online.
Khaligh, Alireza and Omer Onar. Energy Harvesting: Solar, Wind, and Ocean Energy Conversion Systems. CRC Press, 2009. Online.
Mouser Electronics. Solar Energy Harvesting. 2015. http://eu.mouser.com/applications/energy_harvesting_solar/.