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Full-Text Articles in Energy Systems

Comparing Building Modeling Software To The Energy Record Of A Preexisting Structure, Nathan Lasley Jun 2017

Comparing Building Modeling Software To The Energy Record Of A Preexisting Structure, Nathan Lasley

Mahurin Honors College Capstone Experience/Thesis Projects

Buildings are complex systems - even "simple" residential structures. Many factors go into building energy consumption and the design to reduce it. Computer energy modeling allows the simultaneous consideration and balance of many of those variables. Computer models are only as good as the information provided however. Tools like blower door and duct blaster can be used to aid in verifying the model or to provide more information to build a better model. In order to verify of building computer energy simulation methods, the Western Kentucky University (WKU) Office of Sustainability located at 503 Regents Ave. in Bowling Green KY …


Development Of A Dynamic Cfd Model For Offshore Oscillating Water Columns With Non-Linear Interactions, Ken O'Connell Jan 2017

Development Of A Dynamic Cfd Model For Offshore Oscillating Water Columns With Non-Linear Interactions, Ken O'Connell

Theses

This thesis focuses on the development of a state of the art modelling technique for offshore Oscillating Water Column (OWC) type Wave Energy Converters (WEC) using Computational Fluid Dynamics (CFD). Current literature indicates a limited amount of work has been completed on studying these devices containing non-linear time dependent flow phenomenon. Initially, a 2D Numerical Wave Tank (NWT) is studied to reduce discretisation error in order to reproduce accurately propagating waves. Further development into a 3D domain permits the geometrical requirements of an OWC type spar buoy to be included.

In parallel, a single Degree of Freedom (DOF) model is …


How Can Occupancy Modeling And Occupancy Sensors Reduce Energy Usage In Academic Buildings: An Application Approach To University Of San Francisco, Paloma R. Duong May 2016

How Can Occupancy Modeling And Occupancy Sensors Reduce Energy Usage In Academic Buildings: An Application Approach To University Of San Francisco, Paloma R. Duong

Master's Projects and Capstones

Buildings are amongst the highest energy consumers relative to industry and transportation. They account for 40% of the world’s energy consumption, due to the need for lighting, equipment, heating, cooling and ventilation. Academic buildings are multi-purpose buildings that create a challenge on energy reduction. Most are old and have fixed occupancy schedules, resulting in high energy consumption because these buildings experience significant occupancy variation throughout the day. Five academic buildings were analyzed; their building information, energy consumption data and methods to project energy savings have been analyzed. The case studies presented different strategies on predicting energy savings, but these have …


Simulation Of An Air Cooled Single-Effect Solar Absorption Cooling System With Evacuated Tube Collectors, Mohsen Jahandardoost Dec 2015

Simulation Of An Air Cooled Single-Effect Solar Absorption Cooling System With Evacuated Tube Collectors, Mohsen Jahandardoost

UNLV Theses, Dissertations, Professional Papers, and Capstones

Consistently increasing CO2 emission and ozone depletion from synthetic refrigerants are serious environmental issues challenging the scientific community. Absorption cooling systems give scope of utilizing low grade energy source for generating cooling effect. Solar energy is one of these low grade energy sources and with considering the fact that cooling demand increases with the intensity of solar radiation, solar refrigeration has been considered as a logical solution.

This thesis consists of two different simulation stages, in the first stage, a single effect lithium bromide absorption cooling system with constant cooling capacity is modeled and the effect of ambient and generator …


Sensible Air To Air Heat Recovery Strategies In A Passive House, Santiago Martin Rodriguez-Anderson Jan 2015

Sensible Air To Air Heat Recovery Strategies In A Passive House, Santiago Martin Rodriguez-Anderson

Dissertations and Theses

Due to rising energy costs and concerns about global climate change, high performance buildings are more in demand than ever before. With roughly 20% of the total energy consumption in the United States being devoted to residential use, this sector represents a significant opportunity for future savings. There are many guidelines and standards for reducing building energy consumption. One of the most stringent is the Passive House Standard. The standard requires that that air infiltration is less than or equal to 0.6 air changes per hour at a 50 Pascal pressure difference (ACH 50), annual heating energy is less than …


Simulating Energy Efficient Control Of Multiple-Compressor Compressed Air Systems, Sean Murphy, J. Kelly Kissock Jan 2015

Simulating Energy Efficient Control Of Multiple-Compressor Compressed Air Systems, Sean Murphy, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

In many industrial facilities it is common for more than one air compressor to be operating simultaneously to meet the compressed air demand. The individual compressor set-points and how these compressors interact and respond to the facility demand have a significant impact on the compressed air system total power consumption and efficiency. In the past, compressors were staged by cascading the pressure band of each compressor in the system. Modern automatic sequencers now allow more intelligent and efficient staging of air compressors.

AirSim, a compressed air simulation tool, is now able to simulate multiple-compressor systems with pressure band and automatic …


Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson Dec 2014

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …


Economic, Energy And Ghg Emissions Performance Evaluation Of A Whispergen Mk Iv Stirling Engine Μ-Chp Unit In A Domestic Dwelling, Gerry Conroy, Aidan Duffy, Lacour Ayompe May 2014

Economic, Energy And Ghg Emissions Performance Evaluation Of A Whispergen Mk Iv Stirling Engine Μ-Chp Unit In A Domestic Dwelling, Gerry Conroy, Aidan Duffy, Lacour Ayompe

Articles

This paper presents an assessment of the energy, economic and greenhouse gas emissions performances of a WhisperGen Mk IV Stirling engine μ-CHP unit for use in a conventional house in the Republic of Ireland. The energy performance data used in this study was obtained from a field trial carried out in Belfast, Northern Ireland during the period June 2004 - July 2005 by Northern Ireland Electricity and Phoenix Gas working in collaboration with Whispertech UK. A comparative performance analysis between the µ-CHP unit and a condensing gas boiler revealed that the µ-CHP unit resulted in an annual cost saving of …


A Metaevaluation Of Energy Efficiency Evaluations, Brandy Brown Apr 2014

A Metaevaluation Of Energy Efficiency Evaluations, Brandy Brown

Dissertations

This study systematically reviews the methodological characteristics of energy efficiency evaluations and uses metaevaluation to assess its quality. Metaevaluation is used to systematically assess the quality of evaluation products, confirm that evaluations deliver sound findings and conclusions, are useful to the client, are credible, are ethically conducted, and are done as cost-effective as possible. The results of this study show that the ability to accurately assess evaluation for methodological quality using evaluations reports as a primary data source depends on the presence of detailed descriptions of evaluation methods. Furthermore, the study suggests that methodological variations of energy efficiency evaluations coalesce …


Predicting The Performance Of A Solar Domestic Water Heating System With Evacuated Tube Collectors And Hydronic Radiant Flooring, Kimberly Nicole Hammer May 2013

Predicting The Performance Of A Solar Domestic Water Heating System With Evacuated Tube Collectors And Hydronic Radiant Flooring, Kimberly Nicole Hammer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Residential solar thermal system installations have been significantly increasing in the last decade and there exists limited resources for reasonably predicting the performance of those systems. A simulated model is developed in MATLAB® and used to predict the performance of a solar domestic water heating system. In the simulated system, hot water is generated using evacuated tube solar collectors and stored in a domestic hot water storage tank, which utilizes immersed coil heat exchangers. The system is designed to provide hydronic radiant floor heating to its occupants based on the heat loss of a building energy model for an energy-efficient …


Computational Models Of Sub-Divided Thermal Energy Storage Tanks Used In Concentrating Solar Power Plants With Parabolic Trough Collectors, Jesus D. Ortega ^, Vinod Kumar * Apr 2012

Computational Models Of Sub-Divided Thermal Energy Storage Tanks Used In Concentrating Solar Power Plants With Parabolic Trough Collectors, Jesus D. Ortega ^, Vinod Kumar *

COURI Symposium Abstracts, Spring 2012

No abstract provided.


2011 Fall Engr333 Project Final Report, Fall 2011 Engr333 Dec 2011

2011 Fall Engr333 Project Final Report, Fall 2011 Engr333

ENGR 333

Analysis of the Bunker Interpretive Center (BIC) began during the spring of 2011 with the Engineering 382 Instrumentation Lab. To determine the energy use at the BIC, sensing equipment was placed on 44 different energy consuming devices, ranging from pumps to lights to heating and ventilation (HVAC) equipment. These data were collected over the spring and summer and then analyzed by the Engineering 333 Thermal Systems Design class during the fall of 2011. The class was tasked with determining whether or not the BIC was eligible for Energy Star certification. While the building was built to be LEED Gold certified, …


2011 Fall Engr333 Student Seminar Presentation, 2011 Fall Engr333 Dec 2011

2011 Fall Engr333 Student Seminar Presentation, 2011 Fall Engr333

ENGR 333

File for student presentation, given by students in the Fall 2010 class of ENGR333.


2011 Fall Engr333 Project Assignment, Matthew K. Heun Sep 2011

2011 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2011 ENGR333 project focused on the Bunker Interpretive Center (BIC) at Calvin University.

I asked the students “What would it take for Calvin College to obtain an Energy Star rating for the BIC? Or, if the BIC already qualifies for an Energy Star rating, what would it take to improve the energy efficiency of the BIC (as measured by Energy Star metrics) by 15%, thereby ensuring Energy Star performance of the building into the future?”

Customer

As I recall, the customer for this project was Biology faculty member Randy Van Dragt.


Wind Energy Potential For Reverse Osmosis Desalination Plants In La Guajira, Colombia, Carlos Martinez-Smit Jan 2011

Wind Energy Potential For Reverse Osmosis Desalination Plants In La Guajira, Colombia, Carlos Martinez-Smit

Faculty-Selected Student Works

Project report required by the Master of Science Degree in Renewable and Clean Energy.

Abstract:

The region of La Guajira, located in the north of Colombia, has a lot of potential for wind power with annual average wind speeds up to 11 m/s at 10 m height in some locations, according to the national wind map. Most of the wind potential is located in Upper Guajira, where 90% of the population is indigenous Wayuu people (among the country’s poorest population) and it is also characterized with low precipitation, 500 mm/yr, high evapotranspiration, 1500 mm/yr, and low humidity. All this creates …


2010 Fall Engr333 Project Final Report, 2010 Fall Engr333 Dec 2010

2010 Fall Engr333 Project Final Report, 2010 Fall Engr333

ENGR 333

Calvin College dorms have a chronic issue with wasting energy. The dorms have little insulation, high infiltration rates, and are heated by low efficiency boilers. These existing characteristics combine for a larger required heating load and increased energy usage. The excess heat, due to poor temperature control, is often vented out through the windows whenever students deem necessary. This project will attempt to reduce wasted energy and efficiently distribute heat as needed.

The Thermal Systems Design class of 2010 was challenged with retrofitting the Bolt-Heyns-Timmer (BHT) dorm to decrease energy consumption and improve efficiency. The class was presented with the …


Agenda: 2010 World Energy Justice Conference: Emerging Solutions For The Energy Poor: Technological, Entrepreneurial And Institutional Challenges, University Of Colorado Boulder. Center For Energy & Environmental Security, Colorado Journal Of International Environmental Law And Policy Nov 2010

Agenda: 2010 World Energy Justice Conference: Emerging Solutions For The Energy Poor: Technological, Entrepreneurial And Institutional Challenges, University Of Colorado Boulder. Center For Energy & Environmental Security, Colorado Journal Of International Environmental Law And Policy

2010 World Energy Justice Conference (November 5)

This conference is a sequel to the 2009 World Energy Justice Conference (WEJC 2009) which began examining ways of mainstreaming safe, clean, and efficient energy for the world's Energy Poor (EP). The EP number two and a half billion people living on less than $1-2 a day who have no access to modern energy services. WEJC 2010 more fully develops these themes. WEJC 2010 will explore how the next round of global warming meetings in Cancun could design new flexibility mechanisms that give credits, for example, for the reduction of black carbon by the adoption of cookstoves, and embrace small …


2010 Fall Engr333 Project Assignment, Matthew K. Heun Sep 2010

2010 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2010 ENGR333 project focused on heating and air-conditioning in campus dormitories, which are notoriously leaky and inefficient.

I asked the students “What would it take to retrofit the Bolt-Heyns-Timmer (BHT) dormitory heating and air-conditioning systems in a manner that achieves LEED certification?”

Customer

The customer for this project was Calvin’s VP for finance Henry DeVries.


Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory Jan 2010

Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory

Publications (E)

The National Renewable Energy Laboratory (NREL) is the nation’s primary laboratory for renewable energy and energy efficiency research and development.

NREL’s mission and strategy are focused on advancing the U.S. Department of Energy’s and our nation’s energy goals. The laboratory’s scientists and researchers support critical market objectives to accelerate research from scientific innovations to market-viable alternative energy solutions. At the core of this strategic direction are NREL’s research and technology development competencies. These areas span from understanding renewable resources for energy, to the conversion of these resources to renewable electricity and fuels, and ultimately to the use of renewable electricity …


The Very Basics Of Sustainability - An Alternative Viewpoint, Jim Mcgovern Aug 2009

The Very Basics Of Sustainability - An Alternative Viewpoint, Jim Mcgovern

Other resources

This paper examines the context and meaning of the term ‘sustainability’, the factors that determine and govern climate on Earth, the population of the Earth and its trends and influencers, the requirements for sustaining life and the options that are available to humankind. Some viewpoints are presented that are alternative to ‘conventional alternative’ thinking. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’ and also argues that humankind needs to face …


The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern Aug 2009

The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern

Other resources

This presentation sets out the very basics of ‘sustainability’, although a definition of sustainability is not attempted. Some of the very basics are the context in which the Earth and humankind exist in space and time, the Earth’s climate, the Earth’s population and humankind’s options and choices. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’. The author also argues that, in addressing the challenges that humankind faces, globally concerted effort …


Empirically Derived Formulas To Predict Indoor Maximum, Average, And Minimum Temperatures In Roofpond Buildings Using Minimum Climatic Information, Ibrahim Kivarkis Kako Jan 2009

Empirically Derived Formulas To Predict Indoor Maximum, Average, And Minimum Temperatures In Roofpond Buildings Using Minimum Climatic Information, Ibrahim Kivarkis Kako

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis introduces an empirically developed formula to predict the comfort conditions and thermal performance of a Skytherm(TM) Southwest Roofpond placed over a light-weight un-insulated structure built at the School of Architecture at the University of Nevada, Las Vegas.

The predictive formula introduced in this study may be used in different parts of the world (particularly developing nations where insulation and air-conditioning are rarely used) to predict the performance of a Skytherm(TM) Southwest Roofpond using minimal climate data.

The data collected in the experimental setup at the Natural Energies Advanced Technologies Laboratory included outside and inside temperatures of various surfaces …


2008 Fall Engr333 Project Final Report, 2008 Fall Engr333 Dec 2008

2008 Fall Engr333 Project Final Report, 2008 Fall Engr333

ENGR 333

The Calvin College Engineering 333 class of 2008 was challenged with the question, “What would it take to implement an energy efficiency fund at Calvin?” Before addressing this question, another had to be asked: “What is an energy efficiency fund?” An energy efficiency fund is a revolving fund which takes seed money from donations, tuition, or grants and invests it into projects that save energy. Energy cost savings from the projects are routed back to the fund to help it grow and enable it to finance future projects. In order to begin this, the senior engineering students began organizing and …


2008 Fall Engr333 Project Assignment, Matthew K. Heun Sep 2008

2008 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2008 semester ENGR333 project assessed the feasibility of a Green Revolving Fund for Calvin College. I asked the students “What would it take to implement a Calvin Energy Efficiency Fund (CEEF)?”

The project emerged from the work of the previous year’s students who uncovered the concept of green revolving funds.

Immediately after the Fall 2008 semester, I went on sabbatical to South Africa for all of 2009. While I was away, the Calvin administration established the Calvin Energy Recovery Fund (CERF). Over the next decade, CERF saved hundreds of thousands of dollars in energy costs and was …


Using Building Energy Simulation And Geospatial Modeling Techniques In Determine High Resolution Building Sector Energy Consumption Profiles, Shem C. Heiple Jan 2007

Using Building Energy Simulation And Geospatial Modeling Techniques In Determine High Resolution Building Sector Energy Consumption Profiles, Shem C. Heiple

Dissertations and Theses

A technique is presented for estimating hourly and seasonal energy consumption profiles in the building sector at spatial scales down to the individual taxlot or parcel. The method combines annual building energy simulations for cityspecific prototypical buildings and commonly available geospatial data in a Geographical Information System (GIS) framework. Hourly results can be extracted for any day and exported as a raster output at spatial scales as fine as an individual parcel (


Windmill Documentary, Timothy David Stoltenburg Dec 2006

Windmill Documentary, Timothy David Stoltenburg

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.


Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock Apr 2006

Energy Efficient Process Heating: Managing Air Flow, Kevin Carpenter, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

Much energy is lost through excess air flow in and out of process heating equipment. Energy saving opportunities from managing air flow include minimizing combustion air, preheating combustion air, minimizing ventilation air, and reconfiguring openings to reduce leakage.

This paper identifies these opportunities and presents methods to quantify potential energy savings from implementing these energy-savings measures. Case study examples are used to demonstrate the methods and the potential energy savings.The method for calculating savings from minimizing combustion air accounts for improvement in efficiency from increased combustion temperature and decreased combustion gas mass flow rate.

The method for calculating savings from …


Quantifying Savings From Improved Boiler Operation, Kevin Carpenter, J. Kelly Kissock Jan 2005

Quantifying Savings From Improved Boiler Operation, Kevin Carpenter, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

On/off operation and excess combustion air reduce boiler energy efficiency. This paper presents methods to quantify energy savings from switching to modulation control mode and reducing excess air in natural gas fired boilers.

The methods include calculation of combustion temperature, calculation of the relationship between internal convection coefficient and gas flow rate, and calculation of overall heat transfer assuming a parallel-flow heat exchanger model. The method for estimating savings from changing from on/off to modulation control accounts for purge and drift losses through the boiler and the improved heat transfer within the boiler due to the reduced combustion gas flow …


Optimisation Of Heat Transfer And Fluid Flow In The Cooling Of Building Integrated Photovoltaic Facades., Eoin Patrick Hodge Jan 2004

Optimisation Of Heat Transfer And Fluid Flow In The Cooling Of Building Integrated Photovoltaic Facades., Eoin Patrick Hodge

Theses

The aim of this research was to explore the effects of mature and developing technologies from aeronautical industries such as impingement and film cooling, and electronic cooling techniques, in the setting up of different laminar and turbulent flow regimes on PV cooling duct heat transfer rates, with air flow as that brought about with natural buoyancy effects in a vertical building facade. The problem of efficiency losses in PV panels, due to overheating, is one of the factors restricting the development and use of this renewable power source. PV panels can experience very high temperatures, due to the heat input …


Estimating Energy Savings In Compressed Air Systems, Chris Schmidt, J. Kelly Kissock Jan 2004

Estimating Energy Savings In Compressed Air Systems, Chris Schmidt, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

Compressed air is typically one of the most expensive utilities in an industrial facility. As a result, potential savings opportunities are aggressively sought out and identified. Once identified, projected energy savings must be calculated in order to justify the cost of implementing the savings opportunity. It is important to calculate projected energy and cost savings as accurately as possible. Unfortunately, savings are frequently overestimated because the methods used to estimate savings neglect to consider important factors such as compressor control and type, storage, and multiple compressor operation.

In this paper, a methodology is presented for modeling air compressor performance and …