Engineering Commons^™

Pv Powering A Weather Station For Severe Weather, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

A natural disaster, such as Hurricane Andrew, destroys thousands of homes and businesses. The destruction from this storm left thousands of people without communications, potable water, and electric power. This prompted the Florida Solar Energy Center to study the application of solar electric power for use in disasters.

During this same period, volunteers at the Tropical Prediction Center at the National Hurricane Center (NHC) and the Miami Office of the National Weather Service (NWS) were working to increase the quantity and quality of observations received from home weather stations.

Many weather data collecting stations are at remote sites, which are …

Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Retail Strip Mall, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A series of tests were conducted in seven retail shops in a strip mall in Cocoa, Florida to examine how roof whitening would impact air conditioning load. The roof of the strip mall was conventional: unsurfaced galvanized corrugated metal with R-11 insulation suspended by purlins underneath. Below the insulation was the roof plenum which contained both the air handler and duct air distribution system. Cooling was accomplished in each shop by a dedicated direct expansion air conditioning (AC) system between 3 and 4 tons in size. Each had its air conditioning metered for half of the summer in a baseline …

Photovoltaic Equipment For Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Photovoltaic (solar electricity) has been used to power various equipment used in disasters. Previously, no organized program had used photovoltaic powered equipment in disasters. In response to an energy needs study with disaster relief organizations, Sandia National Laboratories for the U.S. Department of Energy sponsored the Florida Solar Energy Center to provide PV equipment to selected disaster relief organizations and evaluate its performance and acceptability. The purpose of the report is to describe the six PV-powered systems that were provided.

Controlling Ventilation And Space Depressurization In Restaurants In Hot And Humid Climates, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Testing was performed in 9 restaurants to identify uncontrolled air flows and pressure imbalances, building and duct system airtightness, building air barrier location, pressure differentials, building air flow balance, and ventilation rates. All restaurants are depressurized under normal operating conditions, ranging from -1.0 to -43 pascals. Space depressurization is a function of exhaust fan flow rates, missing or undersized make-up air, intermittent outdoor air caused by the cycling of air handlers, dirty outdoor air and make-up air filters, and building airtightness. Ventilation rates were found to be high, generally exceeding ASHRAE 62-1989 minimum recommended levels. Pressure imbalances and excessive ventilation …

Moving Mountains With Good Research - A Case Study, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

Mountains can be moved by good ideas based on good research. A wonderful example comes to us from, of all things, the Naval Facilities Command (NAVFAC), headquartered in Washington, DC. This agency of the Department of Defense is responsible for some $5 billion per year in new and retrofit construction, with naval facilities all over the globe. The federal government alone is responsible for $50 billion per year of construction, which Terry Emmons of NAVFAC claims is half of total U.S. construction. It seems that the Navy has 120,000 buildings around the world, some buildings, or groupings, are the size …

Batteries And Charge Control In Stand-Alone Photovoltaic Systems, Florida Solar Energy Center, James Dunlop

FSEC Energy Research Center®

This report presents fundamentals of battery technology and charge control strategies commonly used in stand-alone photovoltaic (PV) systems. This work is a compilation of information from several sources, including PV system design manuals, research reports and data from component manufacturers.

Details are provided about the common types of flooded lead-acid, valve regulated lead-acid, and nickel cadmium cells used in PV systems, including their design and construction, electrochemistry and operational performance characteristics. Comparisons are given for various battery technologies, and considerations for battery subsystem design, auxiliary systems, maintenance and safety are discussed.

Requirements for battery charge control in stand-alone PV systems …

Needs Assessment For Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

When disaster strikes, such as a hurricane, flood, tornado, or earthquake, it can leave many people without adequate medical services, portable water, electrical service and communications. It can be as destructive as Hurricane Andrew, which left several hundred-thousand people homeless. Those fortunate enough to survive the disaster could be without local utility power and other services for long periods of time as services are restored.

When such disasters occur, emergency management teams, the military, and many public and private organizations respond with massive relief efforts. Dependency on electrical utility power becomes pronounced as emergency services are rendered and rebuilding begins. …

Energy Efficiency For Florida Educational Facilities: The 1996 Energy Survey Of Florida Schools, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A detailed survey of energy use and related physical and operational characteristics of Florida's public schools has been completed. A mailed survey instrument was sent to all 2,512 schools throughout the state in March 1996. A total of 1, 298 surveys were returned -- a response rate of approximately 52%. Of these some 680 provided matching utility data. The survey data was analyzed to create a school energy use profile as well as to identify characteristics that may influence efficiency. Based on our findings, the total annual energy cost for the Florida school system totaled $205 million in 1995. As …

The Effect Of Residential Equipment Capacity On Energy Use, Demand, And Run-Time, Florida Solar Energy Center, Jo Ellen Cummings

FSEC Energy Research Center®

Installed central air conditioning system capacities in 368 recently-built Florida homes were compared with Manual J load values calculated from house audit data. Over 50% of the homes had installed systems with a cooling capacity greater than 120% of the calculated Manual J value. Thirty-one percent of the 78 heat pump homes in this study had installed heating capacity greater than 120% of the calculated Manual J value. Using submetered data from the air conditioning system, a definite increase in peak energy use was observed for systems sized over 120% of Manual J calculations. The effect of system sizing on …

Photovoltaic System Design Course For Savannah State College: Course Evaluation, Florida Solar Energy Center, Gerard Ventre

FSEC Energy Research Center®

This report describes the evaluation of a course entitles Photovoltaic System Design (PVSD), which was presented by the Florida Solar Energy Center (FSEC) to faculty members of Savannah State University (SSU). This distance education (DE) course was delivered via a two-way audio/video delivery system from FSEC to SSU. This course evaluation report is included as one of the deliverables in a contract awarded to SSU and FSEC as part of the Advanced Communications Technologies Satellite research project sponsored by the NASA Lewis Research Center, Cleveland, Ohio.

Impact Of Evaporator Coil Air Flow In Residential Air Conditioning Systems, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The performance of conventional split system residential air conditioners is highly dependent on adequate air flow across the evaporator coil. Sufficient air flow is necessary to achieve a proper balance between sensible and latent cooling capacity. Typical target air flow rates are approximately 350 - 450 cubic feet per minute per ton (581 - 747 L/S per kW) of cooling capacity. The authors have measured the air flow across the coil in 27 installations in Florida. Both flow hood and strip heat resistance methods were used to measure air flow with an established protocol. The installations measured ranged in capacity …

Solar Water Heating: A Question And Answer Primer, Florida Solar Energy Center, David L. Block

FSEC Energy Research Center®

Solar water heating is a technology that every homeowner can use to save dollars on utility bills. Questions most frequently addressed to the Florida Solar Energy Center (FSEC) about solar water heating are answered below. Please note that many replies are general and more explanation may be required for those with individual questions. For additional information, contact the FSEC

Solar Water Heating Options In Florida, Florida Solar Energy Center, John Harrison

FSEC Energy Research Center®

This document is intended to acquaint Florida's general public with typical methods of heating household water by means of the sun. The types of solar systems discussed are pumped (both direct and indirect), thermosiphon and integral collector storage.

Identifying Air Flow Failure Modes In Small Commercial Buildings: Tools And Methodologies For Building Commissioning Diagnostics, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

A recent study of small commercial buildings in central Florida found that uncontrolled air flow -- including duct leakage, return air imbalance, and exhaust air/make-up air imbalance -- is widespread. Of 70 buildings studied, only 1 was identified as having no significant uncontrolled air flow. The causes of uncontrolled air flow include failure of design, poor workmanship, O&M problems, HVAC commissioning failures, materials degradation, and building retrofits. This study also found that the consequences of uncontrolled air flow are often quite severe and varied -- including high utility bills, occupant thermal discomfort, high humidity, mold and mildew growth, moisture damage …

Solar Hot Water Energy And Cost Savings For Typical Florida Residential Installations, Florida Solar Energy Center, David L. Block

FSEC Energy Research Center®

The following table presents energy and cost savings for four typical Florida solar water heating systems. Exact savings by a consumer may vary as much as plus or minus 25 from these numbers for numerous reasons. These include hot water usage, storage tank type, thermostat settings, solar system size, collector placement and local weather conditions. Computer simulations were used to generate the energy data.

Solar Heating Of Swimming Pools: A Question & Answer Primer, Florida Solar Energy Center, Charles Cromer

FSEC Energy Research Center®

Solar pool heating is one of the most economically attractive solar technologies in Florida today. If you are interested in heating your pool, or can no longer afford heating it with fossil fuel alone, consider installing a solar pool heater.

The following information helps answer the most frequently asked questions concerning solar pool heating in Florida. Keep in mind that much of this information is "rule of thumb"; your individual situation, if analyzed in detail, may differ somewhat from the general application. A more detailed analysis of pool systems is provided by the publications listed in the bibliography.

Evaluation Of Resources And Energy Systems At Fort Jefferson Garden Key, Dry Tortugas National Park, Florida Solar Energy Center, James Dunlop

FSEC Energy Research Center®

This report presents an evaluation of the resources and energy systems at Fort Jefferson, located on Garden Key in Dry Tortugas National Park, Florida. Conducted by Florida Solar Energy Center staff on June 11-12, 1997, this evaluation builds on a prior evaluation conducted in May 1989. The purpose of this evaluation was to document the energy and resource needs at the site, and to identify possibilities for reduced costs through conservation measures and renewable energy options.

Approximately 700 kWh of electrical energy is used at Fort Jefferson on a daily average, supplied exclusively by diesel-fueled generators. Average diesel fuel consumption …

Batteries And Charge Control In Stand-Alone Photovoltaic Systems: Fundamentals And Application, Florida Solar Energy Center, James Dunlop

FSEC Energy Research Center®

This report presents an overview of battery technology and charge control strategies commonly used in stand-alone photovoltaic (PV) systems. This work is a compilation of information from several sources, including PV system design manuals, research reports, data from component manufacturers, and lessons learned from hardware evaluations.

The Effect Of Varying Temperature, Flux And Pretreatment On The Microfiltration Of Lake Michigan Water, Karen Linda Kopp

Retrospective Theses and Dissertations

This study investigated microfiltration of Lake Michigan Water for the production of drinking water. A 60 gpm Memcor microfiltration pilot plant was operated for nine months at Manitowoc, Wisconsin to determine and model the performance characteristics of a microfiltration pilot plant for varying surface water conditions. Statistical regression and modeling was used to determine and develop quantitative relationships between time of operation and several operational variables for water quality and productivity. Modifications of Darcy's Law and flux decline data were used to develop a model relating temperature and flux to cleaning frequency. Statistical hypothesis testing and associated modeling were used …

Telecourse And Traditional Computer Applications : Exploring The Impact Of Review Sessions, Carol Odette Bourke

Retrospective Theses and Dissertations

The purpose of the study was to explore the effects of review sessions on student achievement and retention in a computer applications course taught by televised distance learning and traditional instruction. Identified within the study were method of instruction, review, and grades in televised and traditional computer applications courses. A quasi-experimental design was used to measure the effects of review sessions on student achievement and retention in computer applications classes. Intact classes were used to form the 4 groups used in this study. Randomization was limited to choices students made in registering for the classes. The control groups for this …

Studies Of Far-Infrared/Submillimeter P-Type Germanium Laser, Kijun Park

Retrospective Theses and Dissertations

A novel p-Ge laser at 165-205 μm wavelengths in Voigt configuration using a regular permanent magnet has been developed and is described here. The necessary magnetic field is provided by a permanent magnet for the first time. Experiments with the traditional, Faraday-configured, superconducting magnet are performed for comparison. Emission is observed over a wider range of electric-field magnitude in Voigt configuration at a· given magnetic field than in Faraday configuration. The spectral response of several different inductive metal meshes for use as output couplers is presented. The widest electric-and magnetic-field range for laser emission was found using a #750 copper …

Field Measurement Of Uncontrolled Air Flow And Depressurization In Restaurants, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Field investigations were done in seven restaurants (subsample of a 63 commercial buildings study) to identify uncontrolled air flows and pressure imbalances. Testing included building airtightness tests, identification of building air barrier location, duct system airtightness, characterization of pressure differentials, building air flow balance, and infiltration/ventilation rates. All restaurants were found to operate at negative pressures which ranged from -0.003 inWC (-0.8 Pa) to -0.173 inWC (-43 Pa) and averaged -0.051 inWC (-12.7 Pa) under normal operation. The variables which affect depressurization are large exhaust fans, missing or undersized make-up air, intermittent outdoor air caused by the cycling of air …

History Of Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, earthquakes, and other disasters can happen any place, any time. Major disasters destroy homes and businesses, and leave many people without adequate medical services, portable water, electrical service and communications. In response to the need for electrical service, solar energy offers a source of quite, safe, pollution-free power. Over the last few years, photovoltaic (solar electricity) power systems have provided energy for various disaster all over the country. Photovoltaics (PV) have been used to power vaccine refrigerators, medical equipment, lighting, radios, fans, communications, traffic devices and other electrical equipment. Previously, photovoltaics have supplied emergency power for Hurricane …

How Contractors Really Size Air Conditioning Systems, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

This paper presents results from 489 of the 5559 Florida air conditioning contractors surveyed (an 8.5% response rate) regarding equipment sizing methods in new residences. Air conditioning sizing is accomplished by using ACCA's Manual-J procedure by 33% of the respondents, software by 34.4% of the respondents, square-footage by 24.2% and other estimate procedures by about 8.4%. Those using square-footage estimates varied from 350 square-feet- per-ton to 700 square-feet-per-ton. Over a third of respondents indicated oversizing intentionally on some jobs, in order to avoid complaints, accommodate future expansions, enable quicker cooling down of homes, and to allow for lower cooling set …

Are Energy Savings Due To Ceiling Fans Just Hot Air?, Florida Solar Energy Center, Patrick James

FSEC Energy Research Center®

Human comfort studies have shown that people prefer higher temperatures when they are subjected to a breeze. Ceiling fans are often used to create air motion in residences. Simulation studies (including one given in this paper) have demonstrated that in Florida, using ceiling fans combined with raising a home's temperature 2° F will generate about a 14% net savings in annual cooling energy use (subtracting out the ceiling fan energy and accounting for internally released heat). This savings drops to 2.6% with a 1° F increase in set point and to a negative 3.7% savings with only a 0.5° F …

Daylight Dimming Systems: Studies In Energy Savings And Efficiency, Florida Solar Energy Center, Lynn Schrum

FSEC Energy Research Center®

Three studies were conducted at Florida Solar Energy Center (FSEC) to study the lighting energy savings of daylight dimming systems. The Daylighting Test Facility (DTF) was used to study daylight dimming systems and how aperture orientation and blinds affect performance. The energy consumption was compared in two pairs of offices for all four window orientations: north, south, east and west. One office in each pair had blinds in a fixed position (down and open) and the other office had no blinds. The study showed that the energy savings ranged from 24% to 51% depending on the orientation and blinds.

The …

Measured Field Performance And Energy Savings Of Occupancy Sensors: Three Case Studies, Florida Solar Energy Center, David Floyd

FSEC Energy Research Center®

Occupancy sensors have the potential to significantly reduce energy use by switching off electrical loads when a normally occupied area is vacated. While occupancy sensors can be used to control a variety of load types, their most popular use has been to control lighting in commercial buildings. Manufacturers claim savings of 15% to 85%, although there is little published research to support the magnitude or timing of reductions. Energy savings and performance are directly related to the total wattage of the load being controlled, effectiveness of the previous control method, occupancy patterns within the space and proper sensor commissioning. In …

Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Our Savior's School, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Architects and designers have long known that light-colored building roofs can reduce cooling needs. Recently, monitoring studies in Florida have made an effort to quantify these savings. Experiments in existing residences have shown that a white reflective roof can reduce cooling requirements by an average of 20%. However, until now there has been no investigation in Florida's climate to examine the potential in commercial scale buildings.

To remedy this need, a two year study was performed on a private elementary school building in Cocoa Beach, Florida. Our Savior's Elementary School was monitored for an entire year in a base line …

Results From A Comprehensive Residential Lighting Retrofit. 09-96, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A single family residence in Miami, Florida was used as a case study to determine how residential lighting energy use could be reduced by substituting energy efficient lamps and fixtures. The three person household was chosen based both on its high utility bills and extensive use of interior lighting. A detailed audit revealed 40 lamps or bulbs on 26 controls (switches) with a total connected load of 2.5 kW.

All major energy using appliances in the home were sub-metered so that lighting and other plug loads could be differenced from the measured total power demand. Also, each of the individual …

Flastar: Florida Alliance For Saving Taxes And Energy Resources. Final Report., Florida Solar Energy Center, John Sherwin

FSEC Energy Research Center®

This document comprises the final project report in supporting the demonstration of the pilot Florida Public Building Loan Concept. This loan program provides low cost funds to eligible public entities for upgrade of building energy systems. The FLASTAR program (Florida Alliance for Saving Taxes And Resources) was modeled after the successful Texas LoanSTAR project [1, 2]. Within that program, funds provided from oil overcharges are loaned to various facilities for building system retrofits. These loans are repaid (with interest) from energy cost savings. As of the most recent reporting, the LoanSTAR program had saved the State of Texas some $13.7 …