Engineering Commons^™

Measured Impacts Of Air Conditioner Condenser Shading, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A study has been conducted by the Florida Solar Energy Center (FSEC) to examine if space cooling energy savings can be achieved from shading of residential air conditioning (AC) condenser units. The investigation consisted of before-and-after experiments conducted on three homes over a two year period. A recent EPA study recommends shading of exterior AC condensers, using landscaping or other means, as a method to reduce space cooling energy use (Akbari et al., 1992).

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 …

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

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

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 …

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 …

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 …

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 …

Measured Natural Cooling Enhancement Of A Whole House Fan, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An experimental study was carried out in the summer of 1991 to investigate the natural cooling potential of use of a whole house fan in Central Florida's hot and humid climate. The residential building, in Cocoa Beach, FL, is typical of much of the existing housing stock in Florida: a concrete block structure with R-11 ceiling insulation. The building was ventilated with all windows open during the three month summer test period (June-August). Air temperatures and relative humidity inside the home interior along with exterior meteorological conditions (insolation, wind speed, air temperature, relative humidity) were scanned every five seconds with …

Impacts Of Duct Leakage On Infiltration Rates, Space Conditioning Energy Use, And Peak Electrical Demand In Florida Homes, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Testing for duct leakage was done in 91 homes. Tracer gas tests found that infiltration rates were four times greater when the air handler was operating than when it was off. Return leaks were found to average 10.0% of air handler total flow. House airtightness, in 63 of these homes, determined by blower door testing, averaged 12.38 air changes per hour at 50 Pascals (ACH50). When the duct registers were sealed, ACH50 decreased to 10.93, indicating that 11.7% of the house leaks were in the duct system.

Duct repairs were made on 25 homes. Blower door tests found 12.30 air …

Field Data Delivery - Thermal Performance Field Monitoring Of Various Conservation Construction Techniques. Final Report., Florida Solar Energy Center, Charles Cromer

FSEC Energy Research Center®

No abstract provided.

Cooling With Ventilation, Florida Solar Energy Center, Subrato Chandra

FSEC Energy Research Center®

In keeping with the national energy policy foal of fostering an adequate supply of energy at a reasonable cost, the United States Department of Energy (DOE) supports a variety of programs to promote a balanced and mixed energy resource system. The mission of the DOE Solar Building Research and Development Program is to support this goal by providing for the development of solar technology alternatives for the buildings sector. It is the goal of the Program to establish a proven technology base to allow industry to develop solar products and designs for buildings that are economically competitive and can contribute …

Latent And Sensible Load Distributions In Conventional And Energy Efficient Residences. Final Report, January 1983 - January 1986. 05-86., Florida Solar Energy Center, Alp Kerestecioglu

FSEC Energy Research Center®

To develop a method to characterize the cooling load distributions in conventional and energy efficient residences, specifically as related to building dehumidification loads, as they pertain to the potential for the use of gas-fired dehumidification and cooling equipment.

Fans To Reduce Cooling Costs In The Southeast, Florida Solar Energy Center, Subrato Chandra

FSEC Energy Research Center®

During the hot, humid summer months in the southeastern U. S., air conditioning costs are a substantial part of the average home's utility bill. In Florida, for example, air conditioning accounts for about 30 percent of the annual utility bill for an all electric house. Fans can help lower air conditioning costs.

There are three generic types of fans to reduce summer air conditioning costs: air circulating fans to create air motion which increases comfort, whole house fans to promote fresh air exchange, and attic vent fans to lower attic temperatures.

Concepts In Passive Design #3 Passive Cooling Categorizations, Florida Solar Energy Center

FSEC Energy Research Center®

Editor's Note: While passive solar heating is relatively well evolved, passive cooling is only on the threshold of development, and many of its terms are new to the practicing professional. At the Fourth Annual Passive Cooling Conference this problem was addressed by William W. Holmes of the University of Nebraska with the presentation of a 10-point categorization of cooling techniques. We are indebted to Mr. Holmes for this contribution to the emerging field of passive cooling and present it here as a point of departure and working vocabulary for the design professional.