Academic literature on the topic 'Power and Energy'

The wave energy power generation-pendulum system (WEPG-PS) is a four-wheeled instrument designed to convert wave power into electric energy. The first wheel is connected to the pendulum by a double freewheel, the second and third are ordinary wheels, while the fourth is a converter component that is axially connected to the electric generator. This design used the Euler-Lagrange formalism and Runge-Kutta method to examine an ideal dimension and determine the numerical solution of the equation of motion related to the rotation speed of the wheels. The result showed that the WEPG-PS' converter system rotated properly when its mass, length, and moment of inertia are 10 kg, 2.0 m, and 0.25 kgm2, respectively. This is in addition to when the radius of the first, second, third, and fourth wheels are 0.5, 0.4, 0.2, and 0.01 m, with inertia values of 0.005, 0.004, 0.003, and 0.1 kgm2. The converter system has the ability to rotate the fourth wheel, which acts as the handle of an electric generator at an angular frequency of approximately 500 - 600 rad/s. The converter system is optimally rotated when driven by a minimum force of 5 N and maximum friction of 0.05. Therefore, the system is used to generate electricity at an amplitude of 0.3 - 0.61 m, 220 V with 50 Hz. Besides, the lower rotation speed and frequency of the energy converter of the WEPG-PS (300 rad/s) and induction generator (50 Hz) were able to generate electric power of 7.5 kW. ©2020. CBIORE-IJRED. All rights reserved

<abstract> <p>Geothermal energy is one of the strategies employed by the Indonesian government to meet rising electricity demand. Developing geothermal energy is often characterized by uncertainties and requires sequential decision-making which is divided into four development phases: 1) identification, 2) exploration, 3) exploitation, and 4) engineering, procurement, construction, and commissioning (EPPC) before it can be commercialized. Traditional valuation techniques often produce a negative net present value (NPV), suggesting decision to reject the project's investment plan. This paper investigates the economic viability of a geothermal power generation project using both NPV and real options analysis (ROA). Costs and uncertainties associated with the various development phases as well as the investment structure of geothermal projects are studied. We develop a framework for assessing the impact of four uncertainties using a binomial lattice: capacity factor, electricity price, make-up well-drilling costs, and operation and maintenance (O&amp;M) costs. Secondary data from an Indonesian context geothermal power plant was used. Positive option values were found for the lattice approach compared to negative values found for the common NPV calculation. The result of this study showed the successful outcome of the exploration stage is very critical to determining the continuation of the project. The framework supports decision-makers in evaluating the impact of geothermal power generation projects in the face of uncertainty by providing a rigorous analysis. The movement of the underlying asset's value in the whole project's lifetime will assist the management in deciding on whether to exit or continue.</p> </abstract>

<abstract> <p>Nuclear energy currently accounts for a declining share of global electricity, but it is possible that rising concerns about global climate change and China's ambitious nuclear program could reverse this trend. This review attempts to assess the global future of nuclear power, showing how the optimistic forecasts in the early days of nuclear power have been replaced by far more modest forecasts. The review first discusses the controversies surrounding nuclear power. It then briefly examines the prospects for three proposed reactors of the future: Small Modular Reactors; Generation IV breeder reactors; fusion reactors. It finally discusses the social and political context for nuclear power, both today and in the future.</p> </abstract>

Tesis para optar al grado de Magíster en Administración
Eduardo Andres Erices Muñoz [Parte I Análisis estratégico y de mercado], Cristian Patricio Torres Rojas [Parte II Análisis organizativo-financiero]
Autores no autorizan el acceso a texto completo de su documento
La necesidad de aumentar la capacidad instalada de la matriz energética del país es un tema que en la última década se ha instalado en la agenda nacional, dado que el crecimiento económico de Chile implica un mayor consumo eléctrico. A su vez, la estrechez energética se ve representada con mayor profundidad en la industria de la minería, especialmente en el norte grande de Chile. El sector minero, además de ser el principal consumidor de energía eléctrica del país, ha experimentado desde el año 2000 una caída sostenida en su productividad, entre otros factores, por los mayores consumos y costos de la energía eléctrica, enfrentando actualmente uno de los precios más altos de América Latina1. Dado lo anterior, el Gobierno está asumiendo un rol más activo, definiendo una Agenda de Energía que incluye como uno de sus ejes el compromiso que un 45% de la capacidad eléctrica que se instalará en el país hasta el año 2025 sean energías renovables no convencionales (ERNC) y, de esta forma, cumplir con la meta de la Ley 20/25 de ingresar a la matriz energética un 20% de ERNC para dicho año. En este sentido, la energía fotovoltaica es una alternativa técnicamente viable para cubrir el consumo eléctrico, principalmente en el norte grande del país, dado que posee un importantísimo potencial solar. El propósito del presente plan de negocios es evaluar la factibilidad económica y financiera de ingresar al negocio de las energías renovables no convencionales, de una manera no convencional. Más allá de este juego de palabras, dado que la mayoría de los proyectos de generación de energía limpia se basan en el modelo de negocios tradicional, o sea generando e inyectando energía al sistema y transando los precios en el mercado spot, la oportunidad de negocio se visualiza en vender directamente la energía a la industria minera, sin intermediarios ni costos de transmisión relevantes. La industria eléctrica nacional está dividida en tres segmentos: generación, transmisión y distribución de energía eléctrica. Las actividades de transmisión y distribución tienen el carácter de monopolio natural. El sector de generación opera en condiciones de competencia, no obstante se caracteriza por ser un mercado altamente concentrado. Asimismo, existen cuatro sistemas eléctricos siendo los dos más importantes el SING (Sistema Interconectado del Norte Grande) y el SIC (Sistema Interconectado Central). La matriz energética del SING se alimenta en un 95% de fuentes térmicas (carbón, diésel, gas natural). En cuanto al desarrollo de proyectos ERNC, a pesar que el país posee condiciones naturales favorables para las energías solar y eólica, recién en el año 2014 se observó un “despegue” de las ERNC en Chile, materializándose proyectos con una capacidad instalada de casi 1.000 MW. Además, a nivel mundial la curva de aprendizaje en el costo de fabricación y operación de la tecnología solar fotovoltaica, ha permitido alcanzar precios competitivos respecto a las fuentes convencionales de energía. El mercado objetivo se concentra en el segmento de generación, a través del suministro eléctrico en base a energías renovables no convencionales, específicamente solar tipo fotovoltaica, para las empresas mineras (cobre) ubicadas en las regiones de Tarapacá y Antofagasta, ya que reúnen las condiciones de vida útil de la faena minera y disponibilidad de terrenos, de acuerdo a la propuesta de valor del proyecto. El modelo de negocios consiste en satisfacer parte de la demanda de energía eléctrica de las empresas mineras señaladas en el párrafo anterior, por medio de una planta solar fotovoltaica de 3 MW de potencia instalada y a través de un contrato de suministro tipo PPA (Power Purchase Agreement) a 20 años. La ventaja competitiva consiste en ofrecer una tarifa estable durante el período del contrato más baja que su tarifa actual en base a generación convencional, lo cual permitirá al cliente capturar y proyectar el ahorro en sus costos operativos. Además, la propuesta tiene la característica que la planta se construirá in-situ, aprovechando la superficie disponible en la faena minera, generando valor compartido en la economía de escala por el costo del terreno y línea de transmisión y conexión eléctrica. La operación y mantenimiento de la planta fotovoltaica estará a cargo de nuestra empresa. Para el desarrollo del negocio, dado que implica montos de inversión relevantes (USD 5,6 millones para cada planta) y se requiere de un respaldo tecnológico y logístico para realizar ese tipo de proyectos, se creará una Unidad Estratégica de Negocio (UEN) denominada “SUN POWER ENERGY” (SPE), bajo la estructura organizacional de E.CL S.A., una de las empresas principales que operan en el SING. Finalmente, en la evaluación financiera se contempla la ejecución de tres plantas solares dentro de los primeros seis años, con un total de aporte de capital requerido de USD 10 millones. Se ha considerado el apalancamiento financiero del proyecto, mediante la obtención de préstamos bancarios por USD 7,8 millones. Como resultado, través del valor actual de los flujos de caja libres descontados a una tasa del 7,5%, se obtiene un valor de la empresa sin deuda de USD 52.382, con una TIR del 7,5% y un periodo de recuperación de la inversión (payback) de 12 años. La TIR del inversionista alcanza al 7,9% con un VAN ajustado de USD 576.161.

The topic of renewable energy is an evergreen subject, especially, in a world dominated by fossil fuels. Renewable energy is widely discussed in the contemporary world because it is unlimited, which means it’s sustainable and does not emit greenhouse gasses that are harmful to the environment and human life. A classic example of renewable energy is wave energy.

La creixent demanda energètica, l’esgotament dels combustibles fòssils i l’augment de l’escalfament global a causa de l’emissió de carboni ha donat lloc a la necessitat d’un sistema energètic alternatiu, global i respectuós amb el medi ambient. L’energia solar es considera una de les formes d’energia més inesgotables d’aquest univers, però té el problema de la baixa eficiència a causa de les diferents condicions ambientals. El panell solar presenta un comportament no lineal en condicions climàtiques reals i la potència de sortida fluctua amb la variació de la irradiació solar i la temperatura. El canvi de les condicions meteorològiques i el comportament no lineal dels sistemes fotovoltaics suposen un repte en el seguiment de diferents PowerPoint màxims. Per tant, per extreure i lliurar contínuament la màxima potència possible del sistema fotovoltaic, en determinades condicions ambientals, s’ha de formular l’estratègia de control de seguiment del punt de potència màxima (MPPT) que funcioni contínuament el sistema fotovoltaic al seu MPP. Es necessita un controlador no lineal robust per garantir el MPPT mitjançant la manipulació de les línies no lineals d’un sistema i el fa robust contra les condicions ambientals canviants. El control de mode lliscant (SMC) s’utilitza àmpliament en sistemes de control no lineals i s’ha implementat en sistemes fotovoltaics (PVC) per rastrejar MPP. SMC és robust contra les pertorbacions, les incerteses del model i les variacions paramètriques. Representa fenòmens indesitjables com el xerramec, inherent al fet que provoca pèrdues d’energia i calor. En aquesta tesi, en primer lloc, es formula un controlador SMC d’ordre sencer per extreure la màxima potència d’un sistema solar fotovoltaic en condicions climàtiques variables que utilitzen l’esquema MPPT de pertorbació i observació (P \ & O) del sistema fotovoltaic autònom proposat. El sistema proposat consta de dos esquemes de bucles, a saber, el bucle de cerca i el bucle de seguiment. P&O MPPT s’utilitza al bucle de cerca per generar el senyal de referència i un controlador SMC de seguiment s’utilitza a l’altre bucle per extreure la màxima potència fotovoltaica. El sistema fotovoltaic es connecta amb la càrrega mitjançant el convertidor d’alimentació electrònic DC-DC de potència. Primer es deriva un model matemàtic del convertidor d’augment i, basat en el model derivat, es formula un SMC per controlar els impulsos de la porta del commutador del convertidor d’augment. L’estabilitat del sistema de bucle tancat es verifica mitjançant el teorema d’estabilitat de Lyapunov. L’esquema de control proposat es prova amb diferents nivells d’irradiació i els resultats de la simulació es comparen amb el controlador de derivades integrals proporcionals clàssiques (PID). El SMC clàssic representa fenòmens indesitjables com el xerramec, inherent al fet que provoca pèrdues d’energia i calor. A la següent part d’aquesta tesi, es discuteix el disseny del controlador de mode lliscant adaptatiu (ASMC) per al sistema fotovoltaic proposat. El control adoptat s’executa mitjançant un ASMC i la millora s’actualitza mitjançant un algorisme d’optimització MPPT de mètode de cerca de patrons millorats (IPSM). S’utilitza un MPPT IPSM per generar la tensió de referència per tal de comandar el controlador ASMC subjacent. S’ha dut a terme una comparació amb altres dos algoritmes d’optimització, a saber, Perturb \ & Observe (P&O) i Particle Swarm Optimization (PSO) amb IPSM per MPPT. Com a estratègia no lineal, l’estabilitat del controlador adaptatiu es garanteix mitjançant la realització d’una anàlisi de Lyapunov. El rendiment de les arquitectures de control proposades es valida comparant les propostes amb la del conegut i àmpliament utilitzat controlador PID.
La creciente demanda de energía, el agotamiento de los combustibles fósiles y el aumento del calentamiento global debido a la emisión de carbono han hecho surgir la necesidad de un sistema energético alternativo, de eficiencia general y respetuoso con el medio ambiente. La energía solar se considera una de las formas de energía más inagotables de este universo, pero tiene el problema de la baja eficiencia debido a las diferentes condiciones ambientales. El panel solar exhibe un comportamiento no lineal en condiciones climáticas reales y la potencia de salida fluctúa con la variación de la irradiancia solar y la temperatura. Las condiciones climáticas cambiantes y el comportamiento no lineal de los sistemas fotovoltaicos plantean un desafío en el seguimiento de la variación máxima de PowerPoint. Por lo tanto, para extraer y entregar continuamente la máxima potencia posible del sistema fotovoltaico, en determinadas condiciones ambientales, se debe formular la estrategia de control de seguimiento del punto de máxima potencia (MPPT) que opere continuamente el sistema fotovoltaico en su MPP. Se requiere un controlador no lineal robusto para asegurar MPPT manejando las no linealidades de un sistema y haciéndolo robusto frente a condiciones ambientales cambiantes. El control de modo deslizante (SMC) se usa ampliamente en sistemas de control no lineales y se ha implementado en sistemas fotovoltaicos (PVC) para rastrear MPP. SMC es robusto contra perturbaciones, incertidumbres del modelo y variaciones paramétricas. Representa fenómenos indeseables como el parloteo, inherentes a él, que provocan pérdidas de energía y calor. En esta tesis, en primer lugar, se formula un controlador SMC de orden entero para extraer la máxima potencia de un sistema fotovoltaico solar en condiciones climáticas variables empleando el esquema MPPT de perturbar y observar (P&O) para el sistema fotovoltaico autónomo propuesto. El sistema propuesto consta de dos esquemas de bucles, a saber, el bucle de búsqueda y el bucle de seguimiento. P&O MPPT se utiliza en el bucle de búsqueda para generar la señal de referencia y se utiliza un controlador SMC de seguimiento en el otro bucle para extraer la máxima potencia fotovoltaica. El sistema fotovoltaico está conectado con la carga a través del convertidor elevador DC-DC electrónico de potencia. Primero se deriva un modelo matemático del convertidor elevador y, en base al modelo derivado, se formula un SMC para controlar los pulsos de puerta del interruptor del convertidor elevador. La estabilidad del sistema de circuito cerrado se verifica mediante el teorema de estabilidad de Lyapunov. El esquema de control propuesto se prueba bajo diferentes niveles de irradiancia y los resultados de la simulación se comparan con el controlador clásico proporcional integral derivado (PID). El SMC clásico describe fenómenos indeseables como el parloteo, inherente a él, que causa pérdidas de energía y calor. En la siguiente parte de esta tesis, se analiza el diseño del controlador de modo deslizante adaptativo (ASMC) para el sistema fotovoltaico propuesto. El control adoptado se ejecuta utilizando un ASMC y la mejora se actualiza utilizando un algoritmo de optimización MPPT del Método de búsqueda de patrón mejorado (IPSM). Se utiliza un IPSM MPPT para generar el voltaje de referencia para controlar el controlador ASMC subyacente. Se ha realizado una comparación con otros dos algoritmos de optimización, a saber, Perturb \ Observe (P&O) y Particle Swarm Optimization (PSO) con IPSM para MPPT. Como estrategia no lineal, la estabilidad del controlador adaptativo está garantizada mediante la realización de un análisis de Lyapunov.
The increasing energy demands, depleting fossil fuels, and increasing global warming due to carbon emission has arisen the need for an alternate, overall efficiency, and environment-friendly energy system. Solar energy is considered to be one of the most inexhaustible forms of energy in this universe, but it has the problem of low efficiency due to varying environmental conditions. Solar panel exhibits nonlinear behavior under real climatic conditions and output power fluctuates with the variation in solar irradiance and temperature. Changing weather conditions and nonlinear behavior of PV systems pose a challenge in the tracking of varying maximum PowerPoint. Hence, to continuously extract and deliver the maximum possible power from the PV system, under given environmental conditions, the maximum power point tracking (MPPT) control strategy needs to be formulated that continuously operates the PV system at its MPP. A robust nonlinear controller is required to ensure MPPT by handling nonlinearities of a system and making it robust against changing environmental conditions. Sliding mode control (SMC) is extensively used in non-linear control systems and has been implemented in photovoltaic systems (PV) to track MPP. SMC is robust against disturbances, model uncertainties, and parametric variations. It depicts undesirable phenomena like chattering, inherent in it causing power and heat losses. In this thesis, first, an integer order SMC controller is formulated for extracting maximum power from a solar PV system under variable climatic conditions employing the perturb and observe (P&O) MPPT scheme for the proposed stand-alone PV system. The proposed system consists of two loops schemes, namely the searching loop and the tracking loop. P&O MPPT is utilized in the searching loop to generate the reference signal and a tracking SMC controller is utilized in the other loop to extract the maximum PV power. PV system is connected with load through the power electronic DC-DC boost converter. A mathematical model of the boost converter is derived first, and based on the derived model, an SMC is formulated to control the gate pulses of the boost converter switch. The closed-loop system stability is verified through the Lyapunov stability theorem. The proposed control scheme is tested under varying irradiance levels and the simulation results are compared with the classical proportional integral derivative (PID) controller. Classical SMC depicts undesirable phenomena like chattering, inherent in it causing power and heat losses. In the next part of this thesis, the design of the adaptive sliding mode controller (ASMC) is discussed for the proposed PV system. The adopted control is executed utilizing an ASMC and the enhancement is actualized utilizing an Improved Pattern Search Method (IPSM) MPPT optimization algorithm. An IPSM MPPT is used to generate the reference voltage in order to command the underlying ASMC controller. Comparison with two other optimization algorithms, namely, a Perturb & Observe (P&O) and Particle Swarm Optimization (PSO) with IPSM for MPPT has been conducted. As a non-linear strategy, the stability of the adaptive controller is guaranteed by conducting a Lyapunov analysis. The performance of the proposed control architectures is validated by comparing the proposals with that of the well-known and widely used PID controller. The simulation results validate that the proposed controller effectively improves the voltage tracking, system power with reduced chattering effect, and steady-state error. A tabular comparison is provided at the end of each optimization algorithm category as a resume quantitative comparison. It is anticipated that this work will serve as a reference and provides important insight into MPPT control of the PV systems.

With the increased loading and exploitation of the power transmission system and also due to improved optimised operation, the problem of voltage stability and voltage collapse attracts more and more attention . A voltage collapse can take place in systems or subsystems and can appear quite abruptly. Continuous monitoring of the system state is therefore required. The cause of the 1977 New York black out has been proved to be the reactive power problem. The 1987 Tokyo black out was believed to be due to reactive power shortage and to a voltage collapse at summer peak load. These facts have strongly indicated that reactive power planning and dispatching play an important role in the security of modern power systems. A proper compensation of system voltage profiles will enhance the system securities in the operation and will reduce system losses. In this thesis, some aspects of reactive power dispatch and voltage control problem have been investigated. The research has focused on the following three issues: Firstly, the steady-state stability problem has been tackled where, a voltage collapse proximity indicator based on the optimal impedance solution of a two bus system has been generalised to an actual system and the performance of this indicator has been investigated over the whole range (stable and unstable region) to see how useful this indicator can be for an operator at any operating point. Then we went further to implement a linear reactive power dispatch algorithm in which this indicator was used for the first time to attempt to prevent a voltage collapse in the system. Secondly, a new efficient technique for N-1 security has been incorporated aiming at either maximising the reactive power reserve margin for the generators or minimising active power losses during normal as well as outage conditions (single line outage) .The reactive power redistribution after an outage is based on the S-E graph adopted by Phadke and Spong[72].Thirdly, the dispatch (N-1 security excluded) has been incorporated on line in the O.C.E.P.S. control package to improve the quality of the service and system security by optimally controlling the generator voltages (potentially the reactive control system is able to control transformers, switchable capacitors and reactors). A new function called load voltage control (similar to the load frequency control function) has been introduced to allow smooth variation of the reactive control signals towards their targets.

This paper briefly presents the results of a study of various utility rate schedules from across the United States and describes a video produced to explain some major features of these rate structures. In particular, the demand, energy and power factor sections of each rate schedule are explored to understand the impacts of selected features on utility costs and on evaluation of energy conservation projects. The accompanying video was produced for the Energy Systems Laboratory's Industrial Assessment Center (IAC) at Texas A&M University. This video will be used during industrial audits to explain typical demand, energy and power factor structures and savings potentials that can be realized by implementation of energy conservation retrofit projects, known as energy conservation opportunities (ECO's), that may be presented through the energy audit process.

The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy storage systems should be designed and operated in order to increase the penetration and value of wind power in the power system. Optimization models and sequential and probabilistic simulation models have been developed for this purpose.

Chapter 3 presents a sequential simulation model of a general windhydrogen energy system. Electrolytic hydrogen is used either as a fuel for transportation or for power generation in a stationary fuel cell. The model is useful for evaluating how hydrogen storage can increase the penetration of wind power in areas with limited or no transmission capacity to the main grid. The simulation model is combined with a cost model in order to study how component sizing and choice of operation strategy influence the performance and economics of the wind-hydrogen system. If the stored hydrogen is not used as a separate product, but merely as electrical energy storage, it should be evaluated against other and more energy efficient storage options such as pumped hydro and redox flow cells. A probabilistic model of a grid-connected wind power plant with a general energy storage unit is presented in chapter 4. The energy storage unit is applied for smoothing wind power fluctuations by providing a firm power output to the grid over a specific period. The method described in the chapter is based on the statistical properties of the wind speed and a general representation of the wind energy conversion system and the energy storage unit. This method allows us to compare different storage solutions.

In chapter 5, energy storage is evaluated as an alternative for increasing the value of wind power in a market-based power system. A method for optimal short-term scheduling of wind power with energy storage has been developed. The basic model employs a dynamic programming algorithm for the scheduling problem. Moreover, different variants of the scheduling problem based on linear programming are presented. During on-line operation, the energy storage is operated to minimize the deviation between the generation schedule and the actual power output of the wind-storage system. It is shown how stochastic dynamic programming can be applied for the on-line operation problem by explicitly taking into account wind forecast uncertainty. The model presented in chapter 6 extends and improves the linear programming model described in chapter 5. An operation strategy based on model predictive control is developed for effective management of uncertainties. The method is applied in a simulation model of a wind-hydrogen system that supplies the local demand for electricity and hydrogen. Utilization of fuel cell heat and electrolytic oxygen as by-products is also considered. Computer simulations show that the developed operation method is beneficial for grid-connected as well as for isolated systems. For isolated systems, the method makes it possible to minimize the usage of backup power and to ensure a secure supply of hydrogen fuel. For grid-connected wind-hydrogen systems, the method could be applied for maximizing the profit from operating in an electricity market.

Comprehensive simulation studies of different example systems have been carried out to obtain knowledge about the benefits and limitations of using energy storage in conjunction with wind power. In order to exploit the opportunities for energy storage in electricity markets, it is crucial that the electrical efficiency of the storage is as high as possible. Energy storage combined with wind power prediction tools makes it possible to take advantage of varying electricity prices as well as reduce imbalance costs. Simulation results show that the imbalance costs of wind power and the electricity price variations must be relatively high to justify the installation of a costly energy storage system. Energy storage is beneficial for wind power integration in power systems with high-cost regulating units, as well as in areas with weak grid connection.

Hydrogen can become an economically viable energy carrier and storage medium for wind energy if hydrogen is introduced into the transportation sector. It is emphasized that seasonal wind speed variations lead to high storage costs if compressed hydrogen tanks are used for long-term storage. Simulation results indicate that reductions in hydrogen storage costs are more important than obtaining low-cost and high-efficient fuel cells and electrolyzers. Furthermore, it will be important to make use of the flexibility that the hydrogen alternative offers regarding sizing, operation and possibly the utilization of oxygen and heat as by-products.

The main scientific contributions from this thesis are the development of

- a simulation model for estimating the cost and energy efficiency of wind-hydrogen systems,

- a probabilistic model for predicting the performance of a gridconnected wind power plant with energy storage,

- optimization models for increasing the value of wind power in electricity markets by the use of hydrogen storage and other energy storage solutions and the system knowledge about wind energy and energy storage that has been obtained by the use of these models.

Paper 1 is reprinted with kind permission of ACTA Press. Paper 2 is reprinted with kind permission of Elsevier/ Science Direct. http://www.elsevier.com, http://www.sciencedirect.com Paper 3 is reprinted with kind permission of IEEE.

This thesis presents an optimal method of designing and controlling an oscillating energy harvesting system. Many new and emerging energy harvesting systems, such as the energy harvesting backpack and ocean wave energy harvesting, capture energy normally expelled through mechanical interactions. Often the nature of the system indicates slow system time constants and unsteady AC voltages. This paper reveals a method for achieving maximum energy harvesting from such sources with fast determination of the optimal operating condition. An energy harvesting backpack, which captures energy from the interaction between the user and the spring decoupled load, is presented in this paper. The new control strategy, maximum energy harvesting control (MEHC), is developed and applied to the energy harvesting backpack system to evaluate the improvement of the MEHC over the basic maximum power point tracking algorithm.
M.S.E.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering MSEE

The objective of the proposed research is to analyze automated residential energy management technology using primary energy source utilization. A residential energy management system (REMS) is an amalgamation of hardware and software that performs residential energy usage monitoring, planning, and control. Primary energy source utilization quantifies power system levels impacts on power generation cost, fuel utilization, and environmental air pollution; based on power system generating constraints and electric load. Automated residential energy management technology performance is quantified through a physically-based REMS simulation. This simulation includes individual appliance operation and accounts for consumer behavior by stochastically varying appliance usage and repeating multiple simulation iterations for each simulated scenario. The effect of the automated REMS under varying levels of control will be considered. Aggregate REMS power system impacts are quantified using primary energy source utilization. This analysis uses a probabilistic economic dispatch algorithm. The economic dispatch algorithm quantifies: fuel usage and subsequent environmental air pollution (EAP) generated; based on power system generating constraints and electric load (no transmission constraints are considered). The analysis will comprehensively explore multiple residential energy management options to achieve demand response. The physically-based REMS simulation will consider the following control options: programmable thermostat, direct load control, smart appliance scheduling, and smart appliance scheduling with a stationary battery. The ability to compare multiple automated residential energy management technology options on an equal basis will guide utility technology investment strategies.

Approved for public release; distribution is unlimited
As the United States Navy makes leaps forward in technology that is being deployed onboard ships, there is a growing need for research to predict what will be needed to integrate new weapon systems with old. Directed energy weapons are being deployed onboard naval platforms starting in 2014, and this paper seeks to answer the question of what energy storage, if any, must be used in conjunction with high-power lasers in order to integrate them with current ships in the fleet. Four energy storage methods are being researched. These storage medias will allow a ship to fire multiple shots from a high-powered laser without taxing the ship’s electrical system. Lead acid batteries, lithium ion batteries, supercapacitors, and flywheels each have their benefits and drawbacks, and those will be discussed. A computer simulation has been developed and used to represent a DDG-51 Arleigh Burke class destroyer and each of the four energy storage methods. This simulation was run repeatedly with different powered high-powered lasers in order to produce a recommendation for what types of energy storage would be necessary to operate these devices onboard ships.