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Monitored Energy Use Patterns In Low-Income Housing In A Hot And Humid Climate, Florida Solar Energy Center, Danny Parker May 1996

Monitored Energy Use Patterns In Low-Income Housing In A Hot And Humid Climate, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) is metering energy use in two Habitat for Humanity developments. The objective is to understand how energy is used in low income housing and how it can be effectively reduced. The ten "control homes" come from a conventional housing project built by in 1993 Habitat for Humanity in Homestead, Florida. Another ten "experimental homes" have been recruited from the 190 home Jordan Commons development in the same vicinity. These houses, which are soon to be metered, are designed to be energy efficient with high SEER air conditioners, reflective roofing, solar water heaters and energy …


Side-By-Side Testing Of Commercial Office Lighting Systems: Two-Lamp Fluorescent Fixtures, Florida Solar Energy Center, Danny Parker May 1996

Side-By-Side Testing Of Commercial Office Lighting Systems: Two-Lamp Fluorescent Fixtures, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Lighting systems in commercial office buildings are primary determinants of building energy use. In warmer climates, lighting energy use has important implications for building cooling loads as well as those directly associated with illumination tasks. To research the comparative performance of conventional and advanced office lighting systems, Florida Solar Energy Center (FSEC) set up the Lighting Flexible Test Facility (LFTF) which allows side-by-side comparison of lighting options in two otherwise identical 2.7 m x 3.7 m (9' x 12') south facing offices.

The ceiling of the LFTF contains 0.61 m x 1.2 m (2' x 4') recessed fluorescent fixtures designed …


Measured Performance Of Energy-Efficient Computer Systems, Florida Solar Energy Center, David Floyd May 1996

Measured Performance Of Energy-Efficient Computer Systems, Florida Solar Energy Center, David Floyd

FSEC Energy Research Center®

The intent of this study is to explore the potential performance of both Energy Star computers/printers and add-on control devices individually, and their expected savings if collectively applied in a typical office building in a hot and humid climate. Recent surveys have shown that the use of personal computer systems in commercial office buildings is expanding rapidly. The energy consumption of such a growing end-use also has a significant impact on the total building power demand. In warmer climates, office equipment energy use has important implications for building cooling loads as well as those directly associated with computing tasks. Recently, …


Daylighting Dimming And Energy Savings: The Effects Of Window Orientation And Blinds, Florida Solar Energy Center, Lynn Schrum Apr 1996

Daylighting Dimming And Energy Savings: The Effects Of Window Orientation And Blinds, Florida Solar Energy Center, Lynn Schrum

FSEC Energy Research Center®

The Daylighting Test Facility (DTF) located at Florida Solar Energy Center, was used to study daylight dimming systems and how orientation and blinds effect energy savings. To evaluate the impact of blinds on dimming savings, 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. From September through December of 1994, data were collected on the north- and south-facing offices. The DTF was rotated 90 degrees and data were …


Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young Apr 1996

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

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, earthquakes, and other disasters can happen at any time, often with little or no advance warning. They can be as destructive as Hurricane Andrew leaving several hundred-thousand people homeless or as minor as an afternoon thunderstorm knocking down local power lines to your home. Major disasters leave many people without adequate medical services, portable water, electrical service and communications. In response to a natural disaster, photovoltaic (solar electric) modules offer a source of quite, safe, pollution-free electrical power. Photovoltaic (PV) power systems are capable of providing the electrical needs for vaccine refrigerators, microscopes, medical equipment, lighting, radios, …


Uncontrolled Air Flow In Non-Residential Buildings, Florida Solar Energy Center, James Cummings Mar 1996

Uncontrolled Air Flow In Non-Residential Buildings, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The objective of this study was to develop the capability to substantially reduce energy use, building degradation and indoor air pollution caused by uncontrolled air flow in nonresidential buildings. For purposes of the study, 'uncontrolled air flow' was defined as air moving across the building envelope or between zones or components of a building, where the pathways of flow, the direction of flow, and the origin of the air are unknown, unspecified, or unintended. The study comes to three major conclusions as follows: 1. Uncontrolled air flow is pervasive in buildings, often resulting in severe -- and sometimes even catastrophic …


Energy Savings From Repair Of Uncontrolled Airflow In Eighteen Small Commercial Buildings, Florida Solar Energy Center, Charles Withers, Jr. Jan 1996

Energy Savings From Repair Of Uncontrolled Airflow In Eighteen Small Commercial Buildings, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Uncontrolled airflow, including duct leakage, pressure imbalances caused by closed interior doors, and exhaust/intake airflow imbalance, was characterized in 70 commercial buildings. In 18 of these buildings, uncontrolled airflows were repaired and energy savings from these repairs were monitored. In most buildings the retrofit was duct repair. In other cases, outdoor airflow was reduced and return air transfers were provided. Cooling energy use was reduced by an average 15.1% in these 18 buildings. With an average repair cost of $455 and average cooling energy savings of $195 per year, uncontrolled airflow retrofits proved to be very cost-effective. Various factors indicate …


Energy Efficient Office Building Design For A Hot And Humid Climate: Florida's New Energy Center, Florida Solar Energy Center, Philip W. Fairey Dec 1995

Energy Efficient Office Building Design For A Hot And Humid Climate: Florida's New Energy Center, Florida Solar Energy Center, Philip W. Fairey

FSEC Energy Research Center®

Hot and humid climates, such as those in Florida, pose unique challenges to architects and engineers seeking energy efficient office building designs. The severe impact of internal loads on cooling, the intense solar conditions and the need for increased ventilation set against high relative humidities, all serve to limit the success of many conventional methods of reducing building energy use. To provide a high-visibility demonstration of potential energy design solutions, the Florida Solar Energy Center (FSEC) is building a state-of-the-art office complex for its new facility in Cocoa, Florida.


The Measured Summer Performance Of Tile Roof Systems And Attic Ventilation Strategies In Hot, Humid Climates, Florida Solar Energy Center, David Beal Dec 1995

The Measured Summer Performance Of Tile Roof Systems And Attic Ventilation Strategies In Hot, Humid Climates, Florida Solar Energy Center, David Beal

FSEC Energy Research Center®

During 1994, simultaneous full-scale testing of residential plywood-decked roofing system was conducted using a flexible roof facility (FRF). The facility consists of a 24-ft by 48ft rectangular building with one large conditioned space under an attic that is partitioned into six separate test cells. Throughout the test protocol one cell was configured as a residential black-shingle roof system, employed as the baseline for comparison of the alternative roofing systems.

Two identical cells were employed during the summer of 1994 to investigate soffit and ridge venting. Tests of two different configurations best illustrate the results. A comparison of a sealed attic …


Measured Cooling Energy Savings From Reflective Roofing Systems In Florida: Field And Laboratory Research Results, Florida Solar Energy Center, Danny Parker Dec 1995

Measured Cooling Energy Savings From Reflective Roofing Systems In Florida: Field And Laboratory Research Results, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A series of field experiments in Florida have examined the impact of reflective roof coatings on air conditioning energy use in occupied homes. The tests were conducted on nine residential buildings from 1991 to 1994 using a before and after protocol where the roofs were whitened at mid-summer. Measured AC electrical savings in the buildings during similar pre- and post-retrofit periods averaged 19%, ranging from a low of 2% to a high of 43%. Utility peak coincident peak savings averaged 22%. Cooling energy reductions appear to depend on ceiling insulation level and roof solar reflectance, air duct system location and …


Florida Exterior Wall Insulation Field Test: Final Report, Florida Solar Energy Center, Stephen Barkaszi Dec 1995

Florida Exterior Wall Insulation Field Test: Final Report, Florida Solar Energy Center, Stephen Barkaszi

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) and Oak Ridge National Laboratory (ORNL) have conducted a field test of exterior insulation applied to Florida masonry residences. Approximately 50% of Florida's six million existing residences are of concrete block construction. Many of these homes, particularly those 15 years or older, have uninsulated walls.

Within the project, two single-family homes in Central Florida were extensively monitored to measure the energy savings of the technology. The primary objective was to examine the effect exterior insulation has on air conditioning (AC) energy use and peak electrical demand for two typical residences. A secondary objective was …


Smarts2, A Simple Model Of The Atmospheric Radiative Transfer Of Sunshine, Florida Solar Energy Center, Christian Gueymard Dec 1995

Smarts2, A Simple Model Of The Atmospheric Radiative Transfer Of Sunshine, Florida Solar Energy Center, Christian Gueymard

FSEC Energy Research Center®

An upgraded spectral radiation model called SMARTS2 is introduced. The solar shortwave direct beam irradiance is calculated from spectral transmittance functions for the main extinction processes in the cloudless atmosphere: Rayleigh scattering, aerosol extinction, and absorption by ozone, uniformly mixed gases, water vapor, and nitrogen dioxide. Temperature-dependent or pressure-dependent extinction coefficients have been developed for all these absorbing gases, based on recent spectroscopic data obtained either directly from the experimental literature or, in a preprocessed form, from MODTRAN2, a state-of-the-art rigorous code. The NO2 extinction effect, in both the UV and visible, is introduced for the first time in a …


Energy Efficiency Technology Demonstration Project For Florida Educational Facilities: Occupancy Sensors, Florida Solar Energy Center, David Floyd Dec 1995

Energy Efficiency Technology Demonstration Project For Florida Educational Facilities: Occupancy Sensors, Florida Solar Energy Center, David Floyd

FSEC Energy Research Center®

In 1995 the Florida Department of Education and the Florida Solar Energy Center jointly sponsored a test of occupancy sensors used to control lighting in a Florida school. Occupancy sensors replace conventional light switches and use passive infrared or ultrasonic sensing to control lighting in classroom and other spaces. The test was intended to demonstrate the performance of such controls in saving energy in Florida educational facilities.

The evaluation was performed at Northwest Elementary School in Pasco County on Florida's west central coast. A before and after monitoring protocol was utilized for the study which saw lighting circuits for 33 …


Photovoltaic Applications For Disaster Relief, Florida Solar Energy Center, William Young Nov 1995

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

FSEC Energy Research Center®

Hurricanes, floods, tornadoes, and earthquakes are natural disasters that can happen at any time destroying homes, businesses, and natural surroundings. One such disaster, Hurricane Andrew, devastated South Florida leaving several hundred-thousand people homeless. Many people were without electrical service, functioning water and sewage systems, communications, and medical services for days, even weeks in the aftermath of the storm. Emergency management teams, the military and countless public and private organizations staged a massive relief effort. Dependency on electrical utility power became a pronounced problem as emergency services were rendered to survivors and the rebuilding process started.

Many of the energy needs …


Indoor Air Quality Impacts Of Uncontrolled Air Flow And Depressurization In Eight Commercial Buildings In Central Florida, Florida Solar Energy Center, James Cummings Sep 1995

Indoor Air Quality Impacts Of Uncontrolled Air Flow And Depressurization In Eight Commercial Buildings In Central Florida, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Field investigations were done in 68 commercial buildings to identify uncontrolled air flows and pressure imbalances. Results from eight buildings (six restaurants and two sports facilities) are reported in this paper. 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. Six restaurants and one sports facility 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. A second sports facility operates partially at positive pressure and …


Field Commissioning Of A Daylight-Dimming Lighting System, Florida Solar Energy Center, David Floyd Jun 1995

Field Commissioning Of A Daylight-Dimming Lighting System, Florida Solar Energy Center, David Floyd

FSEC Energy Research Center®

An Elementary School cafeteria in Florida was commissioned with a fluorescent lighting system that dims in response to available daylight. The lighting system's performance and commissioning aspects were evaluated through real time measurement of lighting and air conditioning power, work plane illumination, and interior/exterior site conditions. The new system produced a 27% reduction in lighting power due to dimming. Lower than expected dimming system performance was observed prior to effective commissioning. Difficulties encountered are discussed as well as recommendations for performance improvements.


Photovoltaic Applications For Disaster Relief. 11-95. Copies 1, 2&3., Florida Solar Energy Center, William Young Jun 1995

Photovoltaic Applications For Disaster Relief. 11-95. Copies 1, 2&3., Florida Solar Energy Center, William Young

FSEC Energy Research Center®

No abstract provided.


Assessment Of Infiltration Practices In The Florida Energy Code, Florida Solar Energy Center, James Cummings Apr 1995

Assessment Of Infiltration Practices In The Florida Energy Code, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The Florida Department of Community Affairs has contracted with the Florida Solar Energy Center (FSEC) to review the current infiltration practices of the Florida Energy Code to determine, based on analysis of the best currently available infiltration data, whether there is need for three infiltration practices, and to make recommendations of what "point multipliers" should be applied to the infiltration practice(s). An advisory committee of industry, utility, and research representatives was formed to review the findings of the project and express opinions about the form the infiltration practices should take. This committee met twice, reviewed each of the reports produced …


Solar Photovoltaic Air Conditioning Of Residential Buildings, Florida Solar Energy Center, Danny Parker Aug 1994

Solar Photovoltaic Air Conditioning Of Residential Buildings, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The use of photovoltaics (PV) for residential air conditioning (AC) represents an attractive application due to the close match between the diurnal cooling load and the availability of solar radiation. Conventional wisdom suggests that air conditioning is a process too energy intensive to be addressed by PV. Previous investigations have concentrated on the feasibility of matching PV output to vapor-compression machines, and the cost effectiveness of other solar cooling options. Recently, Japanese manufacturers have introduced small (8,000 Btu/hr) grid-connected solar assisted AC systems. These small room-sized systems are inadequately sized to meet air conditioning peak demands in larger U.S. homes …


Barriers To Commercialization Of Solar Energy In Florida, Florida Solar Energy Center, Colleen Mccann Kettles Jul 1994

Barriers To Commercialization Of Solar Energy In Florida, Florida Solar Energy Center, Colleen Mccann Kettles

FSEC Energy Research Center®

Florida has a distinct history of solar system development and use. Solar systems have been operating in the State since the 1920s. During the past several decades, solar technologies have advanced and matured, as have the business entities that deliver solar products to the end user. Solar products made in Florida are U.S. and world industry leaders. Quality control measures, such as collector and system testing and certification, contractor training and licensing, and follow-up site inspection, have assured consumer confidence in solar equipment and installation.


Real Life Applications Of Photovoltaic Power To Hurricane Andrew Relief, Florida Solar Energy Center, William Young Mar 1994

Real Life Applications Of Photovoltaic Power To Hurricane Andrew Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

On August 24, 1992, Hurricane Andrew struck the coast of South Florida and devastated Dade County leaving several hundred-thousand people homeless. Over a million residences were without electrical service, functional water and sewage systems and medical services for days and weeks in the aftermath of the storm. Emergency management teams, medical personnel, the military and countless public and private organizations staged a massive relief effort.

The staff at the Florida Solar Energy Center and SANDIA National Laboratory responded to the disaster with photovoltaics (solar electric) powered equipment to assist in the relief effort. Electricity generated by these systems were used …


Laboratory Testing Of The Reflectance Properties Of Roofing Materials, Florida Solar Energy Center, Danny Parker Aug 1993

Laboratory Testing Of The Reflectance Properties Of Roofing Materials, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Past simulation and test cell studies have shown potential reduction to building cooling loads from higher exterior surface solar reflectances (Givoni and Hoffman, 1968; Givoni, 1976; Chuan and Busching, 1983; Griggs and Shipp, 1988; Anderson, 1989; Akbari et al., 1990; Chandra and Moalla, 1991; Bansal et al., 1992). Furthermore, simulation analysis of macro-climatic effects have shown that light colored surfaces may reduce the magnitude of the urban heat island (Taha et al., 1988; Akbari et al, 1989; Akbari et al., 1992).

Figure 1 shows a graphic illustration of the potential influence of surface reflectance on roof solar heat gain. The …


Selecting Windows For South Florida Residences, Florida Solar Energy Center, Ross Mccluney Jan 1993

Selecting Windows For South Florida Residences, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

To provide some guidance to the victims of hurricane Andrew in Dade County, we performed a study of various types of modern glazing systems that might be incorporated in windows for south Florida residences.

The dominant energy impact of residential windows in south Florida comes from the solar radiant heat gain entering these windows and the corresponding heat loads on cooling systems. Thus any extra dollars spent by homeowners to purchase improved replacement windows should be spent in lowering the solar gains of the windows purchased (by reducing glazing shading coefficients or by adding exterior shading devices or vegetation) rather …


The Implementation Of Photovoltaic Transportation Devices, Florida Solar Energy Center, William Young Dec 1992

The Implementation Of Photovoltaic Transportation Devices, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) and the Florida Department of Transportation (FDOT) are currently involved in a program to implement solar electric (photovoltaic) powered applications in the transportation sector. The objective of the program is to encourage the widespread use of cost-effective, transportation related, photovoltaic-powered systems in all areas of traffic control.

Transportation departments have generally relied on conventional practices of using generators, primary batteries, and extensions of utility grid to fulfil their power needs. There exist many remote and conventional electric power requirements within the FDOT that may be effectively satisfied by photovoltaic (PV) power. Applications ranging from …


Rebuilding For Efficiency: Improving The Energy Use Of Reconstructed Residences In South Florida, Florida Solar Energy Center, Danny Parker Dec 1992

Rebuilding For Efficiency: Improving The Energy Use Of Reconstructed Residences In South Florida, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

On August 24th, 1992, Hurricane Andrew devastated a large part of South Dade County in Florida. With over 35,000 homes to be rebuilt, there is interest in seeing if these reconstructed residences can be made more energy-efficient.

This report provides a comprehensive assessment of potential energy efficiency improvements for both new and existing homes in South Florida. Over forty energy-efficiency measures were considered in the analysis. Many homes in the effected zone experienced damage to their windows, roofs and the surrounding landscape. As a result, the analysis closely examined options associated with these design aspects. All major end-uses of electricity …


Hurricane Andrew Photovoltaic Traffic Control Relief, Florida Solar Energy Center, William Young Oct 1992

Hurricane Andrew Photovoltaic Traffic Control Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

On August 24, 1992 Hurricane Andrew damaged and destroyed much of South Florida. The storm destroyed buildings, structures, and traffic devices along the highway. Travel was hazardous with debris in the roadway, traffic signals damaged or not working, and signs missing. This disaster offered a unique opportunity to research and evaluate the potential for using photovoltaic power systems in emergency traffic control situations. This report describes the findings of this study completed by the Florida Solar Energy Center sponsored by the Florida Department of Transportation.


Measured Electricity Savings Of Refrigerator Replacement: Case Study And Analysis, Florida Solar Energy Center, Ted Stedman Aug 1992

Measured Electricity Savings Of Refrigerator Replacement: Case Study And Analysis, Florida Solar Energy Center, Ted Stedman

FSEC Energy Research Center®

There are approximately seven million refrigerator-freezers in the State of Florida. The average demand of these units is at least 1,000 MW. The average life of a residential refrigerator is approximately 20 years (U.S. DOE, 1989). At least 25% of Florida's existing stock are old inefficient units built before the advent of recent appliance efficiency standards. The least efficient are existing models of which approximately 5% of the stock is replaced each year. This represents a significant opportunity for efficiency improvement since recently established standards will greatly improve refrigerator efficiency by 1993 (NAECA, 1987). A number of studies have identified …


Fsec 3.0: Florida Software For Enervironment Computation: V3.0 Draft User's Manual. 01-92, Florida Solar Energy Center, Alp Kerestecioglu Jun 1992

Fsec 3.0: Florida Software For Enervironment Computation: V3.0 Draft User's Manual. 01-92, Florida Solar Energy Center, Alp Kerestecioglu

FSEC Energy Research Center®

FSEC 3.0 was developed to support research. It is a general-purpose software package especially designed to simulate complex building science problems. The program offers several unique features.

The major feature is its ability to solve user-defined systems of governing equations. Up to 250 coupled differential equations and their corresponding boundary conditions may be either selected from libraries or defined by the user. The equations may be linear or nonlinear; spatially-lumped or spatially-distributed; steady-state or transient; ordinary or partial. The structure of the software also allows users to incorporate their own routines or programs. Thus, researchers may define their specific problem …


Simplified Sizing Procedure For Solar Domestic Hot Water Systems, Florida Solar Energy Center, Public Information Office Apr 1992

Simplified Sizing Procedure For Solar Domestic Hot Water Systems, Florida Solar Energy Center, Public Information Office

FSEC Energy Research Center®

This procedure was developed to size residential solar water heating systems in Florida.


Energy-Efficient Lighting For Florida Homes, Florida Solar Energy Center, Danny Parker Mar 1992

Energy-Efficient Lighting For Florida Homes, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Although lighting doesn't constitute a major portion of the average homeowner's electric bill (generally from 3 to 15 percent), you can cut your lighting costs significantly by installing new energy-efficient bulbs. As an added plus for Florida residents, these new bulbs produce less heat, meaning less work for your air conditioner.