Experimental Measurements of Clothes Dryer Drum Heat and Mass Transfer Effectiveness

Accurate system modeling of a clothes dryer requires a drum component that displays correct trends with respect to changing conditions. In this work, a model of drum heat and mass transfer effectiveness is adopted. Within this framework, experimental measurements of drum effectiveness are investigated with respect to several variables: drum volume, load mass, cloth type, drum volumetric air flow rate, and drum entering air temperature. These data can inform the modeling and simulation of any clothes dryer with horizontal-axis, axial-flow tumble-type clothes dryer drum

Moisture performance of sealed attics in the mixed-humid climate

Oak Ridge National Laboratory studied 8 homes in the mixed-humid climate, 4 with vented attics and 4 with sealed attics. ORNL wanted to understand the moisture performance of the sealed attic and how it affected the interior environment. We found that the attic and interior of sealed attic homes were more humid than the attic and interior observed in vented attic homes. This is due to the lack of ventilation in the sealed attic. Historically attics have been vented to dehumidify the attic and interior of the home. A sealed attic design greatly reduces the venting potential and thus this drying pathway and can cause elevated interior moisture over a vented attic home. Despite the elevated attic and interior moisture in the sealed attic homes, so far no mold or material degradation has been found. The roof sheathing moisture content has stayed below 20%, indicating low potential for material degradation. Also the relative humidity at the roof sheathing has stayed within the ASHRAE 160 design criteria except for a short time during the 2011/2012 winter. This was due to a combination of the sealed attic design (minimal venting to the outside) and the duct work not being operated in the attic which usually provides a dehumidification pathway. It was also found that when the humidity was controlled using the HVAC system, it resulted in 7% more cooling energy consumption. In the mixed-humid climate this reduces the cost effectiveness of the sealed attic design as a solution for bringing ducts into a semi-conditioned space. Because of this we are recommending the other alternatives be used to bringing ducts into the conditioned space in both new construction and retrofit work in the mixed-humid climate

Campbell Creek Research Homes FY 2012 Annual Performance Report

The Campbell Creek project is funded and managed by the Tennessee Valley Authority (TVA) Technology Innovation, Energy Efficiency, Power Delivery & and Utilization Office. Technical support is provided under contract by the Oak Ridge National Laboratory (ORNL) and the Electric Power Research Institute.The project was designed to determine the relative energy efficiency of typical new home construction, energy efficiency retrofitting of existing homes, and high -performance new homes built from the ground up for energy efficiency. This project will compare three houses that represented the current construction practice as a base case (Builder House CC1); a modified house that could represent a major energy- efficient retrofit (Retrofit House CC2); and a house constructed from the ground up to be a high- performance home (High Performance House CC3). In order tTo enablehave a valid comparison, it was necessary to simulate occupancy in all three houses and heavily monitor the structural components and the energy usage by component. All three houses are two story, slab on grade, framed construction. CC1 and CC2 are approximately 2,400 square feet2. CC3 has a pantry option, that is primarily used as a mechanical equipment room, that adds approximately 100 square feet2. All three houses are all-electric (with the exception of a gas log fireplace that is not used during the testing), and use air-source heat pumps for heating and cooling. The three homes are located in Knoxville in the Campbell Creek Subdivision. CC1 and CC2 are next door to each other and CC3 is across the street and a couple of houses down. The energy data collected will be used to determine the benefits of retrofit packages and high -performance new home packages. There are over 300 channels of continuous energy performance and thermal comfort data collection in the houses (100 for each house). The data will also be used to evaluate the impact of energy -efficient upgrades ton the envelope, mechanical equipment, or demand -response options. Each retrofit will be evaluated incrementally, by both short -term measurements and computer modeling, using a calibrated model. This report is intended to document the comprehensive testing, data analysis, research, and findings within the January 2011 through October 2012 timeframe at the Campbell Creek research houses. The following sections will provide an in-depth assessment of the technology progression in each of the three research houses. A detailed assessment and evaluation of the energy performance of technologies tested will also be provided. Finally, lessons learned and concluding remarks will be highlighted

Advancing Residential Retrofits in the Mixed Humid Climate to Achieve Deep Energy Savings: Final Report on Knoxville, TN Homes

This is a final report of the Advancing Residential Retrofits in the Mixed Humid Climate to Achieve Deep Energy Savings

Advancing Residential Retrofits in the Mixed Humid Climate to Achieve Deep Energy Savings: Final Report on Knoxville, TN Homes, 2012, October

This is a final report of the Advancing Residential Retrofits in the Mixed Humid Climate to Achieve Deep Energy Savings

CASE STUDY OF DUCT RETROFIT OF A 1985 HOME AND GUIDELINES FOR ATTIC AND CRAWL SPACE DUCT SEALING

The U.S. Department of Energy (DOE) is fully committed to research for developing the information and capabilities necessary to provide cost-effective residential retrofits yielding 50% energy savings within the next several years. Heating, ventilation, and air conditioning (HVAC) is the biggest energy end use in the residential sector, and a significant amount of energy can be wasted through leaky ductwork in unconditioned spaces such as attics and crawl spaces. A detailed duct sealing case study is presented for one house along with nine brief descriptions of other duct retrofits completed in the mixed-humid climate. Costs and estimated energy savings are reported for most of the ten houses. Costs for the retrofits ranged from $0.92/ft2 to$1.80/ft2 of living space and estimated yearly energy cost savings due to the duct retrofits range from 1.8% to 18.5%. Lessons learned and duct sealing guidelines based on these ten houses, as well as close work with the HVAC industry in the mixed-humid climate of East Tennessee, northern Georgia, and south-central Kentucky are presented. It is hoped that the lessons learned and guidelines will influence local HVAC contractors, energy auditors, and homeowners when diagnosing or repairing HVAC duct leakage and will be useful for steering DOE s future research in this area

CASE STUDY OF DUCT RETROFIT OF A 1985 HOME AND GUIDELINES FOR ATTIC AND CRAWL SPACE DUCT SEALING

The U.S. Department of Energy (DOE) is fully committed to research for developing the information and capabilities necessary to provide cost-effective residential retrofits yielding 50% energy savings within the next several years. Heating, ventilation, and air conditioning (HVAC) is the biggest energy end use in the residential sector, and a significant amount of energy can be wasted through leaky ductwork in unconditioned spaces such as attics and crawl spaces. A detailed duct sealing case study is presented for one house along with nine brief descriptions of other duct retrofits completed in the mixed-humid climate. Costs and estimated energy savings are reported for most of the ten houses. Costs for the retrofits ranged from $0.92/ft2 to$1.80/ft2 of living space and estimated yearly energy cost savings due to the duct retrofits range from 1.8% to 18.5%. Lessons learned and duct sealing guidelines based on these ten houses, as well as close work with the HVAC industry in the mixed-humid climate of East Tennessee, northern Georgia, and south-central Kentucky are presented. It is hoped that the lessons learned and guidelines will influence local HVAC contractors, energy auditors, and homeowners when diagnosing or repairing HVAC duct leakage and will be useful for steering DOE s future research in this area

Campbell Creek TVA 2010 First Year Performance Report July 1, 2009 August 31, 2010

This research project was initiated by TVA in March 2008 and encompasses three houses that are of similar size, design and located within the same community - Campbell Creek, Farragut TN with simulated occupancy. This report covers the performance period from July 1, 2009 to August 31, 2010. It is the intent of TVA that this Valley Data will inform electric utilities future residential retrofit incentive program