Exploring Cost-Effective, High Performance Residential Retrofits for Affordable Housing in the Hot Humid Climate

In 2009, a Department of Energy Building America team led by the Florida Solar Energy Center began working with partners to find cost-effective paths for improving the energy performance of existing homes in the hot humid climate. A test-in energy audit and energy use modeling of the partner’s proposed renovation package was performed for 41 affordable and middle income foreclosed homes in Florida and Alabama. HERS1 Indices ranged from 92 to 184 with modeled energy savings ranging from 3% to 50% (average of 26%). Analyses and recommendations were discussed with partners to encourage more efficient retrofits, highlight health and safety issues, and gather feedback on incremental cost of high performance measures. Ten completed renovations have modeled energy savings ranging from 9% to 48% (average 31%.) This paper presents the project’s process including our findings thus far and highlights of the first home to meet the target HERS Index of 70.Florida Solar Energy Cente

Research Results from A Few Alternate Methods of Interior Duct Systems in Factory Built Housing Located In the Hot Humid Climate

The U.S. Department of Energy’s (DOE) Building America1 Industrialized Housing Partnership (BAIHP) has collaborated with two of its industry partners to work on a portion of the project that relates to the construction and evaluation of prototype interior duct systems. In 2006, work began on a duct system design that would locate the entire length of duct work within the air and thermal barriers of the envelope. One of these designs incorporated a high-side supply register that connects to the conventional floor duct. The other design utilized a single soffit located within the conditioned space at the marriage line. The Florida Solar Energy Center’s (FSEC) Manufactured Housing Lab (MHLab) was retrofitted with an interior soffit duct. The duct system was added on so that either the attic duct system or the new interior duct system would be able to supply air to the conditioned space using the same mechanical equipment. The initial results of this work show approximately a 10% to 20% heating/cooling savings when compared to conventional attic duct work construction techniques and nearly 7% savings when compared to a conventional in-floor system

Achieving Airtight Ducts in Manufactured Housing

This Florida Solar Energy Center (FSEC) study, conducted under the auspices of the U.S. Department of Energy's Building America Industrialized Housing Partnership (BAIHP), compares mastic sealed duct systems to tape sealed systems by showing measured total duct leakage (CFM25TOTAL and QnTOTAL) and/or measured leakage to the outside (CFM25OUT and QnOUT) in 190 manufactured home floors or home sections. All manufacturers were considering or actively working toward achieving duct leakage below 3% of the conditioned floor area (QnOUT=0.03), consistent with Energy Star Manufactured Homes criteria. Previous field tests suggest that CFM25OUT accounts for about half of CFM25TOTAL. These data show that achieving CFM25TOTAL=6% during production was generally correlated with achieving CFM25OUT=3% in mastic sealed systems, but less reliably with taped systems. Cost for achieving duct tightness goals range from $4 to$8 including duct testing on the assembly lin

Next Step Toward Widespread Residential Deep Energy Retrofits

The complexity of deep energy retrofits warrants additional training to successfully manage multiple improvements that will change whole house air, heat, and moisture flow dynamics. The home performance contracting industry has responded to these challenges by aggregating skilled labor for assessment of and implementation under one umbrella. Two emerging business models are profiled that seek to resolve many of the challenges, weaknesses, opportunities, and threats described for the conventional business models

Metabolic rate and rates of protein turnover in food-deprived cuttlefish, Sepia officinalis (Linnaeus 1758)

To determine the metabolic response to food deprivation, cuttlefish (Sepia officinalis) juveniles were either fed, fasted (3 to 5 days food deprivation), or starved (12 days food deprivation). Fasting resulted in a decrease in triglyceride levels in the digestive gland, and after 12 days, these lipid reserves were essentially depleted. Oxygen consumption was decreased to 53% and NH4 excretion to 36% of the fed group following 3-5 days of food deprivation. Oxygen consumption remained low in the starved group, but NH4 excretion returned to the level recorded for fed animals during starvation. The fractional rate of protein synthesis of fasting animals decreased to 25% in both mantle and gill compared with fed animals and remained low in the mantle with the onset of starvation. In gill, however, protein synthesis rate increased to a level that was 45% of the fed group during starvation. In mantle, starvation led to an increase in cathepsin A-, B-, H-, and L-like enzyme activity and a 2.3-fold increase in polyubiquitin mRNA that suggested an increase in ubiquitin-proteasome activity. In gill, there was a transient increase in the polyubiquitin transcript levels in the transition from fed through fasted to the starved state and cathepsin A-, B-, H-, and L-like activity was lower in starved compared with fed animals. The response in gill appears more complex, as they better maintain rates of protein synthesis and show no evidence of enhanced protein breakdown through recognized catabolic processes

Optimizing Manufactured Housing Energy Use

In partnership with the Florida Solar Energy Center (FSEC), two manufactured homes were located on North Carolina A&T State University's campus in Greensboro, NC and used in a side-by-side energy consumption comparison. One of the homes was built to the basic HUD code standard and the other was constructed with features expected to produce a home that was 50% more energy efficient. FSEC and NCATSU began monitoring energy performance in both homes. In addition, the performance of each unit was evaluated using a DOE2 based computer energy analysis program developed by FSEC. A comparison of the performance of the units shows a measured energy savings in the more energy efficient unit of 52% for the Heating, cooling, and DHW energy use. This compares well with the energy savings predicted by the FSEC Energy Gauge program of 57%, even when accounting for the warmer than usual winter experienced during the testing period

Clinical and biochemical function of polymorphic NR0B1 GGAA-microsatellites in Ewing sarcoma: a report from the Children\u27s Oncology Group.

BACKGROUND: The genetics involved in Ewing sarcoma susceptibility and prognosis are poorly understood. EWS/FLI and related EWS/ETS chimeras upregulate numerous gene targets via promoter-based GGAA-microsatellite response elements. These microsatellites are highly polymorphic in humans, and preliminary evidence suggests EWS/FLI-mediated gene expression is highly dependent on the number of GGAA motifs within the microsatellite. OBJECTIVES: Here we sought to examine the polymorphic spectrum of a GGAA-microsatellite within the NR0B1 promoter (a critical EWS/FLI target) in primary Ewing sarcoma tumors, and characterize how this polymorphism influences gene expression and clinical outcomes. RESULTS: A complex, bimodal pattern of EWS/FLI-mediated gene expression was observed across a wide range of GGAA motifs, with maximal expression observed in constructs containing 20-26 GGAA motifs. Relative to white European and African controls, the NR0B1 GGAA-microsatellite in tumor cells demonstrated a strong bias for haplotypes containing 21-25 GGAA motifs suggesting a relationship between microsatellite function and disease susceptibility. This selection bias was not a product of microsatellite instability in tumor samples, nor was there a correlation between NR0B1 GGAA-microsatellite polymorphisms and survival outcomes. CONCLUSIONS: These data suggest that GGAA-microsatellite polymorphisms observed in human populations modulate EWS/FLI-mediated gene expression and may influence disease susceptibility in Ewing sarcoma