Lead Performer: Oak Ridge National Laboratory (ORNL) – Oak Ridge, TN
Project Term: FY 2016 - FY 2018
Funding Type: Direct Lab Funding
ORNL’s work in roof and attic research will address the industry need for clear guidance on unvented attics. The wall assemblies research involves a comprehensive evaluation of high-R assemblies. This research supports the Lab and Field Moisture Risk Assessment of Priority High-R Assemblies and Materials under the Moisture Risk Management research area of the Building America roadmap. ORNL will also produce a database where builders will find construction guidance on the evaluated wall assemblies.
ORNL’s work in advanced HVAC solutions for low-load homes will address concerns that low-capacity HVAC systems may have difficulty maintaining comfortable conditions throughout a low-load home due to their low airflow rates relative to the size of space being conditioned. Providing dehumidification separate from cooling is a key feature for providing year-round comfort in low-load homes that have higher latent cooling loads relative to their sensible cooling loads than less-efficient homes.
High-R-value (high-R) building envelope assemblies (i.e., foundation, walls, and roof) exceeding IECC 2012 are the biggest potential home energy-saving measures, according to several analyses by DOE national laboratories. Heating and cooling loads account for nearly 50% of home energy use, and significant end-use savings cannot be achieved without major improvements in building envelope performance. The BTO Emerging Technologies Program, with analysis support from ORNL, determined that high-R building envelope assemblies in new and existing homes can decrease energy use by about 2.75 quads per year, which is nearly 3% of the energy consumed in the United States.
By determining the impact of low airflow on occupant comfort in low-load homes, proper steps can be proactively taken to mitigate the risk of unsatisfied low-load homeowners. Some systems researched in this project are expected to save 40-45% on space heating, space cooling, and water heating energy use over a minimum efficiency heat pump and water heater. In 2009, households in the United States used 1.47 quads of electricity for space heating, space cooling, and water heating. Additionally, in the United States, approximately 14.4 million dwellings use electricity for heating in very cold and cold regions, consuming 0.16 quads of energy annually. A high-performance cold climate heat pump (CCHP) would result in significant savings over current technologies (greater than 70% compared to strip heating). The CCHP can result in annual primary energy savings of 0.1 quads when fully deployed, which is equivalent to a reduction of 5.9 million tons of annual carbon dioxide emissions.
DOE Technology Manager: Eric Werling
Lead Performer: Roderick Jackson, Oak Ridge National Laboratory (ORNL)