Engineering Commons^™

Renewable Energy Limits, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

"The more we get out of the world the less we leave, and in the long run we shall have to pay our debts at a time that may be very inconvenient for our own survival." - Norbert Wiener

Introduction: The world's energy and environmental crises are inextricably linked. The processes of extracting, processing, and burning fossil fuels generates copious pollution of air, water, and land. Fossil-fuel-derived energy lies at the heart of other environmental problems. Fossil energy powers the bulldozers clearing rainforests. It runs the tractors and other farm equipment of industrial agriculture, compacting and mineralizing soils thus increasing …

Qualitative And Statistical Analysis Of The Florida Photovoltaic Rebate Program, Florida Solar Energy Center, Jennifer Szaro

FSEC Energy Research Center®

The Florida Photovoltaic (PV) Rebate Program, which began in March of 1999, has led to the installation of 52 utility interactive PV systems in seven electric utility service territories. The Program offered $4 per installed DC Watt to Florida electric consumers who installed grid-connected photovoltaic equipment in accordance with a series of quality control requirements developed and administered by the Florida Solar Energy Center. All rebated installations are currently being monitored in an effort to collect statistically significant reliability, performance and cost data on grid-connected PV systems. Funding for this program was provided through a one-time grant from the Florida …

Sunup To Sundown - Energygauge Usa 2.0, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

You need special tools to design high-performance homes - residences where energy efficiency creates greater comfort, health, and energy savings. Making decisions about energy efficiency requires the accurate calculation of energy use and demand, and the comprehensive evaluation of proposed improvements.

A new software tool helps meet these requirements. EnergyGauge USA, an hourly simulation tool for the design and analysis of high-performance homes, performs detailed hourly simulation analysis for energy use, ratings and code calculations. Version 2.0 adds many features to the first-generation product, including thermal mass, photovoltaic (PV) system simulation, solar water heating, and detailed hourly outputs.

The software, …

Fsec Approved Solar Energy Systems: Domestic Hot Water And Pool Heating, Florida Solar Energy Center, John Harrison

FSEC Energy Research Center®

This listing contains Florida Energy Factors for solar domestic hot water systems that have been approved by the Florida Solar Energy Center (FSEC) for use in the State. These energy factors represent the dimensionless ratio of the hot water energy made available by each approved system divided by the electrical energy used by the system. The Florida Energy Factor (FEF) is used to determine hot water credit multipliers for residential solar water heating systems in the 1993 Florida Energy Efficiency Code for Building Construction. The FEF can also be used to compare the efficiency of solar water heating systems with …

Air Handler Leakage: Field Testing Results In Residences, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Testing was performed to characterize air leakage in 30 air handler cabinets and at connections to supply and return ductwork. Operating pressures were measured in the air handler and plenums. Q 0.1 (Q 25) in the air handler averaged 23.9 cfm (11.3 l/s) in 30 homes. Leakage at the return and supply ductwork connections averaged 3.9 Q 0.1 (1.8 l/s Q 25) and 2.2 Q 0.1 (1.0 l/s Q 25), respectively. Actual return side leakage of 77.5 cfm (36.6 l/s) and supply side leakage of 3.1 cfm (1.5 l/s) are calculated based on Q 0.1 (Q 25) and measured operating …

Multiple Damage Detection In Structures Using A Coupled Modal Analysis And Wavelet Transform Technique, Nasser S. Bajabaa

Retrospective Theses and Dissertations

A new technique that couples modal analysis and wavelet transforms for detection of multiple damage in structures is introduced. Structural damage may cause local changes in one or more of the following parameters; stiffness, mass and damping that affect the dynamic behavior of the structure. For example, a crack reduces the stiffness of the structure in a localized sense, and thus reducing its natural frequency, and causes changes in both modal damping and mode shapes. In this research, two different structures have been analyzed: beams and plates. First, uniform beams with a single damage (notch) of different sizes at different …

Antenna-Coupled Infrared Focal Plane Array, Francisco Javier Gonzalez

Retrospective Theses and Dissertations

In this dissertation a new type of infrared focal plan array (IR FPA) was investigated, consisting of antenna-coupled microbolometer fabricated using electron-beam lithography. Four different antenna designs were experimentally demonstrated at 10-micron wavelength: dipole, bowtie, square-spiral, and log-periodic. The main differences between these antenna types were their bandwidth, collection area, angular reception pattern, and polarization. To provide pixel collection areas commensurate with typical IR FPA requirements, two configurations were investigated: a two-dimensional serpentine interconnection of individual IR antennas, and a Fresnel-zone-plate (FZP) coupled to a single-element antenna. Optimum spacing conditions for the two-dimensional interconnect were developed. Increased sensitivity was demonstrated …

A Planar Laser-Induced Fluorescence Study On The Effects Of Unsteadiness And Fuel Lewis Number In Hydrogen Laminar Diffusion Flames, Marcos Chaos

Retrospective Theses and Dissertations

Studies on the effect of transport properties coupled with the interaction of fluid dynamics and combustion in acoustically forced laminar hydrogen jet diffusion flames have been performed using the planar laser-induced fluorescence (PLIF) technique. These unsteady diffusion flames are of particular interest because they are reproducible turbulent-like events that can be investigated to gain insight into turbulent combustion. Results reported herein add to the ongoing effort of understanding the complex transport processes taking place in the flames encountered in most modern heat-producing and power-producing devices.

Fuel transport properties (i .e. fuel Lewis number, LeF) were varied by fuel dilution with …

Larger-First Partial Parsing, Sebastian Alexander Van Delden

Retrospective Theses and Dissertations

Larger-first partial parsing is a primarily top-down approach to partial parsing that is opposite to current easy-first, or primarily bottom-up, strategies. A rich partial tree structure is captured by an algorithm that assigns a hierarchy of structural tags to each of the input tokens in a sentence. Part-of-speech tags are first assigned to the words in a sentence by a part-of-speech tagger. A cascade of Deterministic Finite State Automata then uses this part-of-speech information to identify syntactic relations primarily in a descending order of their size. The cascade is divided into four specialized sections: (1) a Comma Network, which identifies …

Solar Dhw Collector Thermal Performance Ratings, Florida Solar Energy Center, John Harrison

FSEC Energy Research Center®

Thermal performance ratings, derived from the FSEC testing and certification program, are a useful tool in comparing the efficiency and economics of various flat-plate solar collectors. Since collectors used in domestic hot water (DHW) systems typically operate in the intermediate temperature range (1200F-1600F), this is the rating provided for comparisons. It must be stressed that these comparisons are only a guide and should not be considered as a rank ordering of collectors. Such considerations as component sizing and proper installation procedures are equally important in determining a system's overall efficiency. In addition, because of the variability of weather conditions, instrumentation …

Flexible Roofing Facility: 2001 Summer Test Results, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

The Flexible Roof Facility (FRF) is a test facility in Cocoa, Florida designed to evaluate five roofing systems at a time against a control roof with dark shingles. The intent of the testing is to evaluate how roofing systems impact summer residential cooling energy use and peak demand. In the summer of 2001, the following roofing systems were tested.

Cell # Description

1. Weathered white barrel tile with sealed attic
2. Double roof with radiant barrier, sealed attic and insulated roof deck
3. High reflectance brown metal shingle with vented attic
4. Terra cotta barrel tile with vented attic
5. Dark shingles with standard attic …

Energy And Environmental Integration Through A Green Municipality Designation, Florida Solar Energy Center, Eric Martin

FSEC Energy Research Center®

Most local green building programs in existence seek to bestow a "green designation" on a builder, building owner, or developer with residential, commercial, and development standards. Municipalities, however, play an important role in making green building become "business as usual" rather than a conscious choice made by few. Municipalities can set an example to the community by incorporating green building techniques in the construction and operation of public and government buildings, play a vital role in community education, and can create incentives and mandates to foster green building within the community. Florida's green building program has set out to create …

Field Testing And Computer Modeling To Characterize The Energy Impacts Of Air Handler Leakage, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

In order to determine the impact of air handler location upon heating and cooling energy use, the amount of air leakage which occurs in the air handler cabinet needs to be known. Also, the leakage which occurs at the connections between the air handler cabinet and the return and supply plenums needs to be known as well because these connection leaks would also be located in the attic or any other location.

In order to assess this leakage, testing was performed on a total of 69 air conditioning systems. Thirty systems were tested in the year 2001 under funding from …

Measured And Simulated Cooling Performance Comparison; Insulated Concrete Form Versus Frame Construction, Florida Solar Energy Center, Dave Chasar

FSEC Energy Research Center®

Four occupied homes near Dallas, Texas were monitored to compare cooling energy use. Two homes were built with typical wood frame construction, the other two with insulated concrete form (ICF) construction. Remote data loggers collected hourly readings of indoor and outdoor temperature, relative humidity, furnace runtime fraction, total building electrical energy and HVAC energy use. Data was recorded from January through August 2000.

Analysis of the measured data shows that insulated concrete form (ICF) construction can reduce seasonal cooling energy use 17 - 19% over frame construction in two-story homes in the North Texas climate. This result includes adjustments to …

Comparative Evaluation Of The Impact Of Roofing Systems On Residential Cooling Energy Demand In Florida, Florida Solar Energy Center, John Sherwin

FSEC Energy Research Center®

Roof and attic thermal performance exert a powerful influence on cooling energy use in Florida homes. The Florida Power and Light Company and the Florida Solar Energy Center instrumented six side-by-side Habitat homes in Ft. Myers, Florida with identical floor plans and orientation, R-19 ceiling insulation, but with different roofing systems designed to reduce attic heat gain. A seventh house had an unvented attic with insulation on the underside of the roof deck rather than the ceiling: (RGS) Standard dark shingles (control home); (RWB) White "Barrel" S-tile roof; (RWS) Light colored shingles; (RWF) White flat tile roof; (RTB) Terra cotta …

Design And Construction Of Interior Duct Systems, Florida Solar Energy Center, Janet Mcilvaine

FSEC Energy Research Center®

To combat the energy, durability, and indoor air quality penalties of duct leakage, energy experts have recommended putting the duct system and air handler inside the conditioned space. Two paths of accomplishing this have emerged: unvented attics/crawl spaces and interior chases. This study focuses on the design, construction, and performance of the interior chase approach as implemented by five different builders in Texas, North Carolina, and Florida.

Researchers found that, in many cases, breeches of the air barrier were evident from simple visual inspection. Critical points of design and construction were identified and will be presented through photos, design and …

Solar Oven Development And Testing Contract Final Report, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) was contracted by the Dorothy Ann Foundation (and its agent and representative, Darwin O. Curtis), to conduct an investigative study into the development of a state-of-the art solar cooker. A major goal of the contract was to investigate the potential means of improving the performance and long-term durability of the existing Cookit solar cooker.

Many of the activities and accomplishments conducted as part of this contract have been provided in the reports and analyses previously sent to the contact representative. The purpose of this final report is to list the various task accomplishments defined …

Solar Thermal Billing Program In Florida, Florida Solar Energy Center, Carlos Colon

FSEC Energy Research Center®

This paper presents the development, implementation, and results of Lakeland Electric's solar thermal billing program in Florida. The three-phase solar program was started in 1997 with funds from the Florida Energy Office (FEO) and the technical assistance of the Florida Solar Energy Center (FSEC). It was designed as a model to expand the concept of distributed energy generation, and to augment the use of solar domestic hot water (SDHW) systems. The solar thermal billing program relies on the proceeds generated from the sale of hot water energy. Twenty-nine SDHW systems, which are owned by Lakeland Electric (LE), gradually began operation …

Performance And Impact From Duct Repair And Ventilation Modifications Of Two Newly Constructed Manufactured Houses Located In A Hot And Humid Climate, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Two nearly identical houses situated next to each other in Bossier City, Louisiana were studied in an effort to better understand moisture and cooling energy related problems in manufactured houses with low thermostat set-points during the cooling season. By design, the major difference between houses was the type of air conditioning units. House A had a standard split air conditioner and House B had a two-speed split air conditioner.

In an effort to make the buildings more similar, the building airtightness was adjusted until it was the same in each house, and duct leaks were sealed so that the ducts …

Suggested Methodologies For Determining The Shgc Of Complex Fenestration Systems For Nfrc Ratings, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

Simple fenestration systems, for the purpose of this paper, are those whose solar heat gain and visible transmittance performances can be accurately simulated using the Window 4 or 5 programs developed at Lawrence Berkeley National Laboratory (LBNL). Complex fenestrations are everything else, including obscure or "privacy" glazing, corrugated or otherwise complex patterned glazing, curved, bent, or domed glazing, fritted glazing, glass blocks, glass fiber reinforced plastic daylighting panels, and glazings with internal or attached shading systems of a variety of types. The latter include exterior awnings and overhangs, attached exterior shade screens and shutters (including roll-up shutters), between-the-panes shades, including …

Research Highlightsfrom A Large Scale Residential Monitoring Study In A Hot Climate, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

This load research project by a large utility has monitored 204 residences in Central Florida, collecting detailed electricity end-use load data. In each home, 15-minute electric demand data is obtained on total electric power, space heating, cooling, water heating, dryers, cooking and pool energy use. Interior and exterior temperatures were also recorded. This is similar to other detailed end-use data monitored in the U.S. Pacific Northwest in the ELCAP project (Pratt et al., 1989) and the PG&E Appliance Metering Project (Brodsky and McNicoll, 1987). However these data are of a more recent vintage and from a cooling dominated climate.

The …

Sunsmart Community Partnerships: Summary And Lessons Learned Report, Florida Solar Energy Center, Jennifer Szaro

FSEC Energy Research Center®

Through a working partnership with the Florida Municipal Electric Association (FMEA), the Florida Solar Energy Center (FSEC), the Florida Municipal Power Agency (FMPA), the Legal Environmental Assistance Foundation (LEAF), and FMEA member utilities, the SunSmart program offers a unified, low-cost solution to providing municipal electric customers with a solar energy option. It also provides its member utilities with a high level of technical and administrative support to alleviate concerns about working with an unfamiliar electric generation technology. It relies on a core team to develop a standardized marketing and public outreach plan which can be utilized by all participants, and …

New Architecture For Heterogeneous Real-Time Simulation, Mandar Anil Mathure

Retrospective Theses and Dissertations

This thesis investigates a new architecture for modeling and simulating complex distributed real-time systems. Modeling adequately a large distributed real time system may involve, due to its complexity, several different theoretical vehicles such as queuing theory, finite state machines, and others. Currently there are no software tools, which would offer combining such heterogeneous features into a single comprehensive simulation environment.

This study involves integrating 3 tools, SES/workbench, an offline simulator using queuing theory as its modeling discipline, ObjecTime as a real-time simulator based on finite state machines as its modeling discipline, and VxWorks real-time kernel used for free modeling in …

Design And Analysis Of Class Ab Rf Power Amplifier For Wireless Communication Applications, Mohamed El-Dakroury

Retrospective Theses and Dissertations

The Power Amplifier is the most power-consulting block among the building blocks of RF transceivers. It is still a difficult problem to design power amplifiers, especially for linear, low voltage operation. Until now power amplifiers for wireless applications is being produced almost in GaAs processes with some exceptions in LDMOS, Si BJT, and SiGe HBT. The submicron CMOS processes for power amplifiers are under research focus since CMOS offers integration for power amplifier with rest of the transceivers blocks due to its high yield. Also CMOS process is cheap.

This thesis report details the design process of a class AB …

High Frequency Communication System Modeling And Performance Enhancement, Employing Novel Adaptive Dsp Techniques, Murad M. Qahwash

Retrospective Theses and Dissertations

High Frequency (HF) communication has been shown to be a useful communication technique from the very beginning of World War I and it accelerated during World War II. This is attributed to its simplicity, ability to provide near globe connectivity at low power without repeaters, moderate cost, and ease of proliferation [1]. In fact, the HF communication system utilizes the ionosphere [2][3][4] to refract the skywave signals to a distant receiver. This ionospheric channel has some disadvantages. First, it is a non-stationary channel as the HF frequency propagation is a function of the sun spot activities, solar winds, and diurnal …

Investigation Of Reflective Materials For The Solar Cooker, Florida Solar Energy Center, John Harrison

FSEC Energy Research Center®

A critical task in developing a solar cooker is to identify reflector materials that would be both suitable for this application as well as economical. FSEC has conducted an extensive search for available reflective materials. This has included contacting reflective materials manufacturers as well as national laboratories that are currently working with private industry in developing reflector that can be used primarily on large concentrating solar energy devices. This investigation used a variety of resources. These included the FSEC solar library, web search engines, solar industry catalogs and directories, personal contacts, aluminum industry sources, solar cooker discussion groups, and a …

Industry Guide To Selecting The Best Residential Window Options For The Florida Climate (Revised), Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

It used to be said that windows are little more than holes in the insulation. It is true to some extent that poorly insulated and drafty windows in certain climates defeat the purpose of wall insulation. However, modern high performance windows are almost as good as opaque insulated wall sections, at least in terms of total energy savings over long periods of time. In some cases, they can be shown to actually out-perform insulated walls. Of course, they have the priceless additional benefits of providing views to the outdoors and natural daylight illumination indoors important issues of quality and comfort. …

Moisture Problems In Manufactured Housing: Probable Causes And Cures, Florida Solar Energy Center, Neil Moyer

FSEC Energy Research Center®

A significant number of new manufactured houses built to HUD code and located in the hot, humid Southeast are experiencing moisture problems. Soft wallboards, buckled floors, damaged wood molding and extensive mold growth are the most common symptoms. These problems do not respond to the standard service and repair strategies for water intrusion

At the request of four manufacturers, over twenty-five such moisture damaged homes were investigated in 1999 and 2000 to determine likely causes. One time blower door, duct tightness and pressure differential measurements were performed on all homes. Field data on ambient, crawlspace, belly and house temperatures and …

An Analysis Of Greenhouse Cookpot Design Considerations For Low-Cost Solar Cookers, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

This analysis is prepared as part of a research project on low-cost solar cookers conducted by the Florida Solar Energy Center for the Dorothy Ann Foundation on behalf of Solar Household Energy, Inc. The overall purpose of the research project is to improve the performance, reliability and cost-effectiveness of low-cost solar cookers for use in developing nations. The analysis reported here concentrates solely on the cookpot and "greenhouse" design considerations for such systems.

Lightweight Cigs2 Thin-Film Solar Cells On Stainless Steel Foil, Florida Solar Energy Center, Neelkanth Dhere

FSEC Energy Research Center®

AM 0 PV parameters of large-grain, {112} orientated chalcopyrite CIGS2 thin films solar cells on 127µm thick SS flexible foil for space power were: V_oc = 802.9 mV, J_sc = 25.07 mA/cm², FF = 60.06%, and efficiency 0 = 8.84%. Detailed current versus voltage analysis gave values of series resistance Rs, shunt resistance Rp, diode factor A, and reverse saturation current Jo of ~0.1 Ω cm2, ~600 Ω cm2, ~2.2 and ~1.85x10^-8 A cm^-2 respectively. A sharp QE cutoff was observed at CIGS2 bandgap of ~1.50 eV. Higher foil roughness resulted in a preliminary …