Energy Systems Commons^™

A Decision Support System For Ship’S Energy Efficient Operation : Based On Artificial Neural Network Method, Yasser Bayoumy Abdelwahab Farag

World Maritime University Dissertations

No abstract provided.

Optimising Energy Efficiency : Split Incentives In The Context Of The Implementation Of Seemp, Edwin Nii Oduah Mensah

World Maritime University Dissertations

No abstract provided.

Analytical Assessment Of Port Energy Efficiency And Management . : A Case Study Of The Kenya Ports Authority, Maryam Mohamed Kidere

World Maritime University Dissertations

No abstract provided.

Semi-Annual Program Progress Performance Report For University Transportation Systems Pppr#8, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

The major activity of the past reporting period has been the completing of the final project research reports. During the period, twelve projects (numbers 3, 7, 10, 14, 17, 9, 22, 4, 5, 13, 20 and 18) were completed and the final project reports forwarded to DOT and the required associated organizations. Two additional final reports (numbers 12 and 21) are close to being completed. Final reports for the other 4 remaining projects (numbers 2, 8, 11 and 15) are in various stages of completion. For this reporting period, EVTC researchers concluded 12 project final reports, authored one publication, made …

Note On The Rate And Energy Efficiency Limits For Additive Manufacturing, Timothy Gutowski, Sheng Jiang, Daniel Cooper, Gero Corman, Michael Hausmann, Jan-Anders Manson, Timo Schudeleit, Konrad Wegener, Matias Sabelle, Jorge Ramos-Grez, Dusan P. Sekulic

Mechanical Engineering Faculty Publications

We review the process rates and energy intensities of various additive processing technologies and focus on recent progress in improving these metrics for laser powder bed fusion processing of metals, and filament and pellet extrusion processing of polymers and composites. Over the last decade, observed progress in raw build rates has been quite substantial, with laser metal processes improving by about 1 order of magnitude, and polymer extrusion processes by more than 2 orders of magnitude. We develop simple heat transfer models that explain these improvements, point to other possible strategies for improvement, and highlight rate limits. We observe a …

Torrefaction Kinetics Of Hemp Hurds, An Emerging Agricultural Byproduct, In A Small Retort, Tel Jensen

Civil and Environmental Engineering Undergraduate Honors Theses

As knowledge concerning the consequences of unsustainable energy sources and agricultural practices grows, development of low-impact alternatives to both becomes more important. Sustainable sources of biomass offer solutions to both problems. This study characterized the reaction kinetics of torrefying an agricultural byproduct, the woody interior of hemp stems, or hurds. Torrefaction was carried out at 250 °C in small and simple retorts made of galvanized steel pipe. A first-order model most closely approximated the reaction. A sensitivity analysis was performed and the data was adjusted to correct for three potential sources of error, and regressed to find the best fit …

Measured Performance Of A High-Efficiency Solar-Assisted Heat Pump Water Heater, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

This paper describes a novel solar photovoltaic-assisted heat pump water heater (PV-HPWH). The system uses two 310 Wp PV modules, micro-inverters and innovative controls to produce and store daily hot water. The system likely costs half that of solar thermal systems, with greater reliability, no freeze protection and potentially superior performance in cloudy locations. Moreover, no net metering is needed for the PV, which with two modules makes for a simple installation.The HPWH controls have been modified through experimentation such that higher tank temperatures are achieved during the day when solar availability is high while avoiding triggering the compressor during …

Evaluation Of Heat Available From Calcium Chloride Desiccant Hydration Reaction For Domestic Heating In San Francisco, Ca, Michael Giglio

Mechanical Engineering Master's Theses

Thermochemical energy storage has the potential to support the use of solar thermal energy collection in ways that traditional thermal energy storage, like sensible and latent heat storage, have fallen short. Thermochemical energy storage has been shown to have higher storage capacities than sensible and latent storage for dehumidifying applications and does not require insulation like sensible and latent heating do. Sensible heating is focused on maintaining an increased temperature of a storage medium while latent heat storage is focused on maintaining a phase of the storage material. Both sensible and latent heat storage have been shown to have lower …

Phased Deep Retrofit Project: Real-Time Measurement Of Energy End-Uses And Retrofit Opportunities, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

This paper describes how utilities can 'make reductions real' through real-time measurement of energy end-uses and corresponding retrofit opportunities. A field evaluation of the methodology was conducted from 2012 to 2016 with Florida Power and Light (FPL), an investor owned utility. A collaborative program between the U.S. Department of Energy (DOE) Building America and FPL led to an ambitious residential energy-efficiency retrofit study aimed to represent FPL's customer base. Fifty-six existing, all electric, occupied Florida homes were instrumented to collect one-minute data on most all energy end-uses in advance of energy-efficiency retrofits. Baseline measurements enabled the development of end-use profiles …

Spectral Phonon Relaxation Time Calculation Tool Based On Molecular Dynamics, Divya Chalise, Tianli Feng, Xiulin Ruan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermal conductivity is an important material property which affects the performance of a wide range of devices from thermoelectrics to nanoelectronics. Information about phonon vibration modes and phonon relaxation time gives significant insight into understanding and engineering material’s thermal conductivity. Although different theoretical models have been developed for studying phonon modes and relaxation time, extensive knowledge of lattice dynamics and molecular dynamics is required to compute phonon modal frequencies and relaxation times. Therefore, a computational tool which can take simple inputs to calculate phonon mode frequencies and relaxation time will be beneficial. Through this research work, such computational tool has …

Numerical Simulations Of Transcritical Natural Convection, Ruiwen Wei, Carlo Scalo, Mario Tindaro Migliorino, Kukjin Kim, Jean-Pierre Hickey

The Summer Undergraduate Research Fellowship (SURF) Symposium

In modern engineering applications, system overheating is a key issue that needs to be solved with efficient and reliable cooling technologies. Among the possible mechanisms that these are based on, natural convection cooling is one of the most frequently employed, with applications ranging from cooling of computer micro-components to large nuclear reactors. While many studies have been performed on natural convection employing supercritical or subcritical fluids, little attention has been given to fluids in their transcritical regime. The latter has the potential to yield high performances while avoiding detrimental effects of two-phase systems (e.g. cavitation). In the present study, 2D …

Enhancing The Performance Of A Transportable Environmental Control Unit (Ecu) Operated In High-Temperature Climates, Quan Jun Sun, Ammar M. Bahman, Eckhard A. Groll

The Summer Undergraduate Research Fellowship (SURF) Symposium

Numerous people live or venture into environments, such as the Middle East, where the temperatures can skyrocket as high as 54°C. This leaves many air conditioners unable to operate efficiently. Although much research has been conducted for incorporating vapor injection processes into refrigeration systems, such as ones used in supermarkets, little has been researched regarding the application in extreme heat environments. While most basic air conditioning units do not require the addition of a vapor injection process along with an economizer, this project requires the air conditioning (AC) unit to operate under extreme high temperature conditions. The project investigates the …

Secondary Atomization: Drop Breakup In A Continuous Air Jet, Grant S. Sondgeroth, Longchao Yao, Catriona M.L. White, Daniel R. Guildenbecher, Jun Chen, Paul E. Sojka

The Summer Undergraduate Research Fellowship (SURF) Symposium

Understanding drop breakup will optimize aircraft engine performance, reduce agro-chemical overspray, and improve pharmaceutical tablet efficacy. Large fuel fragments in engines lead to lowered fuel economy and higher pollutant emissions, while small drops yield more agro-spray drift into surrounding residential and environmental zones. Better pharmaceutical tablets will improve drug uptake and patient comfort.

Engineers and scientists are currently unable to predict the number, size, and velocity of fragments formed during important drop breakup processes. Therefore, we are required to measure these quantities. We use digital inline holography (DIH) to record three-dimensional diameter and position data for fragments formed during multi-mode …

A Spreadsheet Algorithm For Determining The Economic Feasibility Of Micro-Chp Systems In The Arkansas Manufacturing Sector, Ford R. Lewallen

Graduate Theses and Dissertations

Combined heat and power (CHP) systems are not new to the market. However, advances in technology, specifically MicroTurbines, have presented new opportunities for installations of micro-CHP units - defined as 50 kWe to 300 kWe, specifically at small- to medium-sized industrial facilities. One pressing concern is whether or not an industrial plant has a high enough process thermal load requirement to fully utilize the energy output.

This thesis will discuss simulations that were run on several actual electric and thermal load combinations, which correspond to types of manufacturing facilities commonly found in Arkansas. Analysis of the plant usage profiles will …

An Economic Analysis Of Residential Photovoltaic Systems With And Without Energy Storage, Rodney Moses Kizito

Graduate Theses and Dissertations

Residential photovoltaic (PV) systems serve as a source of electricity generation that is separate from the traditional utilities. Investor investment into residential PV systems provides several financial benefits such as federal tax credit incentives for installation, net metering credit from excess generated electricity added back to the grid, and savings in price per kilowatt-hour (kWh) from the PV system generation versus the increasing conventional utility price per kWh. As much benefit as stand-alone PV systems present, the incorporation of energy storage yields even greater benefits. Energy storage (ES) is capable of storing unused PV provided energy from daytime periods of …

Piezoelectric Bistable Buckled Beam Energy Harvester., Brian Edward Allgeier

Electronic Theses and Dissertations

A novel energy harvesting device design is presented to be created via microfabrication techniques. Such devices have countless applications for powering low-current electrical devices, especially wireless sensors or transmitters. This micro-electromechanical system (MEMS) design utilizes the piezoelectric response of a bistable buckled beam to gather electrical energy via ambient vibrations. While many traditional piezoelectric energy harvesters (PEH) consist of simple cantilever beam geometries, this nonlinear design utilizes inertial effects of torsional lever arms to actuate a central buckled beam to snap between its two stable states; such an abrupt strain on the piezoelectric beam potentially produces a significantly increased electrical …

Socio-Economic Implications Of Large-Scale Electric Vehicle Systems, Florida Solar Energy Center, Omer Tatari

FSEC Energy Research Center®

Transportation is a complex, technology-intensive socio-technical system, which needs to be tackled in an integrated manner. Also, transportation as a sector is a significant component of any national economy, and has far-reaching implications both with regard to socio-economic and environmental well-being of the society and within the context of sustainability science. For this reason, sustainable transportation is not only an important field of research within the academia but also an indispensable constituent of a sustainable economy. Therefore, investigating the path to sustainable transportation requires a holistic approach, encompassing the three dimensions of sustainability, i.e. environment, society, and economy. There are …

Evaluation And Enhancement Of Clean Energy Systems: Analytical, Computational And Experimental Study Of Solar And Nuclear Cycles, Nima Fathi

Mechanical Engineering ETDs

Clean (and specifically renewable) energy is steadily improving its global share. However, finite availability of fossil fuels and the growing effects of climate change make it an urgent priority to convince the industry and governments to incentivize investment in the renewable energy field and to make it more attractive by decreasing the capital cost. Until recently, uncertainties in funding limited renewable energy development, especially in the US. That limitation has been one of the barriers to progress. Another limitation of many renewable energy systems is the variability in their output, which makes them unsuitable for baseline power production. Therefore, fossil …

The Impact Of Power Curve Estimation On Commercial Wind Power Forecasts - An Empirical Analysis, Gianni Goretti, Aidan Duffy, Tek Tjing Lie

Conference papers

An increasing number of utilities participating in the energy market require short term (i.e. up to 48 hours) power forecasts for renewable generation in order to optimize technical and financial performances. As a result, a large number of forecast providers now operate in the marketplace, each using different methods and offering a wide range of services. This paper assesses five different day-ahead wind power forecasts generated by various service providers currently operating in the market, and compares their performance against the state-of-the-art of short-term wind power forecasting. The work focuses on how power curve estimations can introduce systematic errors that …

Energy From Chemical Reactions: Understanding The Combustion Engine, Tammy Guthrie, Kathy Prophet, Greg Herzig, Cassie Kautzer

Middle School Lesson Plans

Automobiles produce a large amount of heat generated by the burning of gasoline. Burning gasoline is a chemical reaction that causes a phase change. This is called combustible energy. During combustion fuel combines with oxygen to release energy (such as heat, light, sound) along with another product that is often considered waste. Most of the energy produced is not used to power the automobile, but is released as heat. 19.3 pounds of the greenhouse gas, carbon dioxide, is produced from the combustion of 1 gallon of U.S. gasoline according to the U.S. Energy Information Administration.