Matching Items (16)

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Experimental Measurements of Power Output of a Cu/Cu2+ Thermogalvanic Brick using Effective Electrode Surface Area Alterations

Description

The research analyzes the transformation of wasted thermal energy into a usable form through thermogalvanic devices. This technology helps mitigate international growing energy demands. Building energy efficiency is a critical research topic, since the loads account for 40% of all

The research analyzes the transformation of wasted thermal energy into a usable form through thermogalvanic devices. This technology helps mitigate international growing energy demands. Building energy efficiency is a critical research topic, since the loads account for 40% of all energy demand in developed nations, and 30% in less developed nations. A significant portion of the energy consumed for heating and cooling, where a majority is dissipated to the ambient as waste heat. This research answers how much power output (µW·cm-2) can the thermogalvanic brick experimentally produce from an induced temperature gradient? While there are multiple avenues for the initial and optimized prototype design, one key area of interest relating to thermogalvanic devices is the effective surface area of the electrodes. This report highlights the experimental power output measurements of a Cu/Cu2+ thermogalvanic brick by manipulating the effective surface area of the electrodes. Across three meshes, the maximum power output normalized for temperature was found to be between 2.13-2.87 x 10-3 μWcm-2K-2. The highest normalized power output corresponded to the mesh with the highest effective surface area, which was classified as the fine mesh. This intuitively aligned with the theoretical understanding of surface area and maximum power output, where decreasing the activation resistance also reduces the internal resistance, which increases the theoretical maximum power.

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Date Created
2019-05

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The Process of an Energy Retrofit at ASU

Description

This study aims to teach the reader about the process of making a building more energy efficient at ASU. In this study the importance of energy efficiency in buildings will be discussed as well as how building efficiency is important

This study aims to teach the reader about the process of making a building more energy efficient at ASU. In this study the importance of energy efficiency in buildings will be discussed as well as how building efficiency is important for the three tiers of sustainability. The case of energy efficiency in the environment, economy, and society will be outlined with the intent of creating urgency for the implementation of energy efficiency. Environment, economy, and society, the three tiers of sustainability fit the model of energy efficiency because efficient energy is a principle of sustainability. Efficient energy can fill the gap between our energy system at present and the energy system of the future. This document outlines the steps that ASU goes through when there is an energy upgrade to a building on campus. It also includes a mock audit of the Psychology North building at ASU. This mock audit serves as an example to justify how the steps outlined in this document can be used to initiate an energy retrofit. A person who reads this document will be able to understand the energy retrofit process. The main argument is that there is room for student inclusion in this process, by giving students the knowledge on how to initiate an energy retrofit they have the tools to be included. Practicing building efficiency on campus will help ASU to succeed in accomplishing numbers two and four of their sustainability goals: "1) Carbon Neutrality, 2) Zero Solid/Water Waste, 3) Active Engagement, and 4) Principled Practice" (ASU, 2011).

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Date Created
2017-05

Our Greener Home Energy Toolkit: DIY Home Energy Solutions for Johnson City, TN

Description

This study examines the creation of a sustainability toolkit that can be implemented in many communities, beginning with Johnson City, Tennessee. This project began in 2019 and will continue to grow indefinitely. For this project, a toolkit that will allow

This study examines the creation of a sustainability toolkit that can be implemented in many communities, beginning with Johnson City, Tennessee. This project began in 2019 and will continue to grow indefinitely. For this project, a toolkit that will allow the public to have access to the tools and information they need in order to make their homes more energy-efficient will be created. It will be stocked in the local library in Johnson City Tennessee for free use to the public, as long as they have a library card, they can check out the toolkits. The toolkits will be used by the public, then returned to the library so that they can be restocked and checked out again. This study looks at the market, business and organizational research and the infrastructure of the project. Methods of research included looking at how the need for a change came about, who will benefit, existing similar programs and how they will be used in conjunction with this project, current organizational structures attached to the project, current team infrastructure and what resources are needed to fill the voids. Findings include what financial resources will be required and how they will be acquired, as well as resources that are currently available for this project and what is still needed in order for this project to be successful. As a result of this project, at least two libraries in the Johnson City area will be stocked with several energy toolkits for free and a partnership for future project expansion will have been established. This study looks at the process and what was learned during the implementation of the project.

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2020-05-18

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Energy-efficient distributed estimation by utilizing a nonlinear amplifier

Description

Distributed estimation uses many inexpensive sensors to compose an accurate estimate of a given parameter. It is frequently implemented using wireless sensor networks. There have been several studies on optimizing power allocation in wireless sensor networks used for distributed estimation,

Distributed estimation uses many inexpensive sensors to compose an accurate estimate of a given parameter. It is frequently implemented using wireless sensor networks. There have been several studies on optimizing power allocation in wireless sensor networks used for distributed estimation, the vast majority of which assume linear radio-frequency amplifiers. Linear amplifiers are inherently inefficient, so in this dissertation nonlinear amplifiers are examined to gain efficiency while operating distributed sensor networks. This research presents a method to boost efficiency by operating the amplifiers in the nonlinear region of operation. Operating amplifiers nonlinearly presents new challenges. First, nonlinear amplifier characteristics change across manufacturing process variation, temperature, operating voltage, and aging. Secondly, the equations conventionally used for estimators and performance expectations in linear amplify-and-forward systems fail. To compensate for the first challenge, predistortion is utilized not to linearize amplifiers but rather to force them to fit a common nonlinear limiting amplifier model close to the inherent amplifier performance. This minimizes the power impact and the training requirements for predistortion. Second, new estimators are required that account for transmitter nonlinearity. This research derives analytically and confirms via simulation new estimators and performance expectation equations for use in nonlinear distributed estimation. An additional complication when operating nonlinear amplifiers in a wireless environment is the influence of varied and potentially unknown channel gains. The impact of these varied gains and both measurement and channel noise sources on estimation performance are analyzed in this paper. Techniques for minimizing the estimate variance are developed. It is shown that optimizing transmitter power allocation to minimize estimate variance for the most-compressed parameter measurement is equivalent to the problem for linear sensors. Finally, a method for operating distributed estimation in a multipath environment is presented that is capable of developing robust estimates for a wide range of Rician K-factors. This dissertation demonstrates that implementing distributed estimation using nonlinear sensors can boost system efficiency and is compatible with existing techniques from the literature for boosting efficiency at the system level via sensor power allocation. Nonlinear transmitters work best when channel gains are known and channel noise and receiver noise levels are low.

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Date Created
2013

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Energy efficiency policy in Arizona: public participation and expert consultation in the policy implementation process

Description

Many different levels of government, organizations, and programs actively shape the future of energy in Arizona, a state that lacks a comprehensive energy plan. Disparate actions by multiple actors may slow the energy policy process rather than expedite it. The

Many different levels of government, organizations, and programs actively shape the future of energy in Arizona, a state that lacks a comprehensive energy plan. Disparate actions by multiple actors may slow the energy policy process rather than expedite it. The absence of a state energy policy or plan raises questions about how multiple actors and ideas engage with state energy policy development and whether the absence of a comprehensive state plan can be understood. Improving how policy development is conceptualized and giving more focused attention to the mechanisms by which interested parties become involved in shaping Arizona energy policy. To explore these questions, I examine the future energy efficiency. Initially, public engagement mechanisms were examined for their role in policy creation from a theoretical perspective. Next a prominent public engagement forum that was dedicated to the topic of the Arizona's energy future was examined, mapping its process and conclusions onto a policy process model. The first part of this thesis involves an experimental expert consultation panel which was convened to amplify and refine the results of a public forum. The second part utilizes an online follow up survey to complete unfinished ideas from the focus group. The experiment flowed from a hypothesis that formal expert discussion on energy efficiency policies, guided by the recommendations put forth by the public engagement forum on energy in Arizona, would result in an increase in relevance while providing a forum for interdisciplinary collaboration that is atypical in today's energy discussions. This experiment was designed and evaluated utilizing a public engagement framework that incorporated theoretical and empirical elements. Specifically, I adapted elements of three methods of public and expert engagement used in policy development to create a consultation process that was contextualized to energy efficiency stakeholders in Arizona and their unique constraints. The goal of the consultation process was to refine preferences about policy options by expert stakeholders into actionable goals that could achieve advancement on policy implementation. As a corollary goal, the research set out to define implementation barriers, refine policy ideas, and operationalize Arizona-centric goals for the future of energy efficiency.

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Date Created
2013

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Sustainability of intercity transportation infrastructure: assessing the energy consumption and greenhouse gas emissions of high-speed rail in the U.S

Description

In the U.S., high-speed passenger rail has recently become an active political topic, with multiple corridors currently being considered through federal and state level initiatives. One frequently cited benefit of high-speed rail proposals is that they offer a transition to

In the U.S., high-speed passenger rail has recently become an active political topic, with multiple corridors currently being considered through federal and state level initiatives. One frequently cited benefit of high-speed rail proposals is that they offer a transition to a more sustainable transportation system with reduced greenhouse gas emissions and fossil energy consumption. This study investigates the feasibility of high-speed rail development as a long-term greenhouse gas emission mitigation strategy while considering major uncertainties in the technological and operational characteristics of intercity travel. First, I develop a general model for evaluating the emissions impact of intercity travel modes. This model incorporates aspects of life-cycle assessment and technological forecasting. The model is then used to compare future scenarios of energy and greenhouse gas emissions associated with the development of high-speed rail and other intercity travel technologies. Three specific rail corridors are evaluated and policy guidelines are developed regarding the emissions impacts of these investments. The results suggest prioritizing high-speed rail investments on short, dense corridors with fewer stops. Likewise, less emphasis should be placed on larger investments that require long construction times due to risks associated with payback of embedded emissions as competing technology improves.

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Created

Date Created
2011

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Short-term reduction of peak loads in commercial buildings in a hot and dry climate

Description

A major problem faced by electric utilities is the need to meet electric loads during certain times of peak demand. One of the widely adopted and promising programs is demand response (DR) where building owners are encouraged, by way of

A major problem faced by electric utilities is the need to meet electric loads during certain times of peak demand. One of the widely adopted and promising programs is demand response (DR) where building owners are encouraged, by way of financial incentives, to reduce their electric loads during a few hours of the day when the electric utility is likely to encounter peak loads. In this thesis, we investigate the effect of various DR measures and their resulting indoor occupant comfort implications, on two prototype commercial buildings in the hot and dry climate of Phoenix, AZ. The focus of this study is commercial buildings during peak hours and peak days. Two types of office buildings are modeled using a detailed building energy simulation program (EnergyPlus V6.0.0): medium size office building (53,600 sq. ft.) and large size office building (498,600 sq. ft.). The two prototype buildings selected are those advocated by the Department of Energy and adopted by ASHRAE in the framework of ongoing work on ASHRAE standard 90.1 which reflect 80% of the commercial buildings in the US. After due diligence, the peak time window is selected to be 12:00-18:00 PM (6 hour window). The days when utility companies require demand reduction mostly fall during hot summer days. Therefore, two days, the summer high-peak (15th July) and the mid-peak (29th June) days are selected to perform our investigations. The impact of building thermal mass as well as several other measures such as reducing lighting levels, increasing thermostat set points, adjusting supply air temperature, resetting chilled water temperature are studied using the EnergyPlus building energy simulation program. Subsequently the simulation results are summarized in tabular form so as to provide practical guidance and recommendations of which DR measures are appropriate for different levels of DR reductions and the associated percentage values of people dissatisfied (PPD). This type of tabular recommendations is of direct usefulness to the building owners and operators contemplating DR response. The methodology can be extended to other building types and climates as needed.

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Date Created
2012

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A longitudinal study of the post-occupancy energy performance of K-12 school buildings in Arizona

Description

Energy performance and efficiency plays of major role in the operations of K-12 schools, as it is a significant expense and a source of budgetary pressure upon schools. Energy performance is tied to the physical infrastructure of schools, as well

Energy performance and efficiency plays of major role in the operations of K-12 schools, as it is a significant expense and a source of budgetary pressure upon schools. Energy performance is tied to the physical infrastructure of schools, as well as the operational and behavioral patterns they accommodate. Little documentation exists within the existing literature on the measured post-occupancy performance of schools once they have begun measuring and tracking their energy performance. Further, little is known about the patterns of change over time in regard to energy performance and whether there is differentiation in these patterns between school districts.

This paper examines the annual Energy Use Intensity (EUI) of 28 different K-12 schools within the Phoenix Metropolitan Region of Arizona over the span of five years and presents an analysis of changes in energy performance resulting from the measurement of energy use in K-12 schools. This paper also analyzes the patterns of change in energy use over time and provides a comparison of these patterns by school district.

An analysis of the energy performance data for the selected schools revealed a significant positive impact on the ability for schools to improve their energy performance through ongoing performance measurement. However, while schools tend to be able to make energy improvements through the implementation of energy measurement and performance tracking, deviation may exist in their ability to maintain ongoing energy performance over time. The results suggest that implementation of ongoing measurement is likely to produce positive impacts on the energy performance of schools, however further research is recommended to enhance and refine these results.

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Date Created
2015

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Sustainable cloud computing

Description

Energy consumption of the data centers worldwide is rapidly growing fueled by ever-increasing demand for Cloud computing applications ranging from social networking to e-commerce. Understandably, ensuring energy-efficiency and sustainability of Cloud data centers without compromising performance is important for both

Energy consumption of the data centers worldwide is rapidly growing fueled by ever-increasing demand for Cloud computing applications ranging from social networking to e-commerce. Understandably, ensuring energy-efficiency and sustainability of Cloud data centers without compromising performance is important for both economic and environmental reasons. This dissertation develops a cyber-physical multi-tier server and workload management architecture which operates at the local and the global (geo-distributed) data center level. We devise optimization frameworks for each tier to optimize energy consumption, energy cost and carbon footprint of the data centers. The proposed solutions are aware of various energy management tradeoffs that manifest due to the cyber-physical interactions in data centers, while providing provable guarantee on the solutions' computation efficiency and energy/cost efficiency. The local data center level energy management takes into account the impact of server consolidation on the cooling energy, avoids cooling-computing power tradeoff, and optimizes the total energy (computing and cooling energy) considering the data centers' technology trends (servers' power proportionality and cooling system power efficiency). The global data center level cost management explores the diversity of the data centers to minimize the utility cost while satisfying the carbon cap requirement of the Cloud and while dealing with the adversity of the prediction error on the data center parameters. Finally, the synergy of the local and the global data center energy and cost optimization is shown to help towards achieving carbon neutrality (net-zero) in a cost efficient manner.

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Date Created
2014

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Operational and technological peak load shifting strategies for residential buildings

Description

Residential air conditioning systems represent a critical load for many electric

utilities, especially for those who serve customers in hot climates. In hot and dry

climates, in particular, the cooling load is usually relatively low during night hours and

early mornings and hits

Residential air conditioning systems represent a critical load for many electric

utilities, especially for those who serve customers in hot climates. In hot and dry

climates, in particular, the cooling load is usually relatively low during night hours and

early mornings and hits its maximum in the late afternoon. If electric loads could be

shifted from peak hours (e.g., late afternoon) to off-peak hours (e.g., late morning), not

only would building operation costs decrease, the need to run peaker plants, which

typically use more fossil fuels than non-peaker plants, would also decrease. Thus, shifting

electricity consumption from peak to off-peak hours promotes economic and

environmental savings. Operational and technological strategies can reduce the load

during peak hours by shifting cooling operation from on-peak hours to off-peak hours.

Although operational peak load shifting strategies such as precooling may require

mechanical cooling (e.g., in climates like Phoenix, Arizona), this cooling is less

expensive than on-peak cooling due to demand charges or time-based price plans.

Precooling is an operational shift, rather than a technological one, and is thus widely

accessible to utilities’ customer base. This dissertation compares the effects of different

precooling strategies in a Phoenix-based utility’s residential customer market and

assesses the impact of technological enhancements (e.g., energy efficiency measures and

solar photovoltaic system) on the performance of precooling. This dissertation focuses on

the operational and technological peak load shifting strategies that are feasible for

residential buildings and discusses the advantages of each in terms of peak energy

savings and residential electricity cost savings.

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Agent

Created

Date Created
2016