Zero Energy Ready Home Research Articles

The environmental impact of the zero energy ready home program on manufactured housing

Manufactured homes, which are built in the factory and shipped to the site, provide economical housing for more than 20 million Americans. To improve energy measures and facilitate deployment of renewable energy systems to achieve net zero energy in manufactured homes, the U.S. Department of Energy (DOE) made public the Zero Energy Ready Home (ZERH) National Program Requirements for manufactured housing in 2022. To understand how these changes will impact the environment and the building’s durability, life cycle assessment and hygrothermal simulations were carried out for a standard manufactured home design and two ZERH designs in Knoxville, Tennessee. The embodied carbon and operational emissions were compared for the standard design and two ZERH designs for a service life of 60 years. Operational emissions were determined using the Building Energy Optimization tool, BEopt, and durability assessment was carried out using WUFI Pro. Life cycle assessment was performed in accordance with ISO 14040 using Athena’s Impact Estimator for buildings. Results indicate that the investment in embodied carbon of the zero energy ready homes is small relative to the savings in operational emissions. The increase in embodied carbon in the zero energy ready homes is offset by the reduction in operational emissions compared to the standard home for the first year of operation. With an investment of 59 kg CO2 eq in embodied carbon, the reduction in operational emissions is approximately 680 kg CO2 eq after one year compared to a construction that meets the prescriptive performance of the building code for manufactured housing.

NAILING THE HOT WATER & HEATING SYSTEMS IN HIGH PERFORMANCE HOMES: ONE BUILDER'S RESEARCH PROJECT

INTRODUCTION In 2005, Martha Rose Construction Inc. (MRC) upgraded the specs in their Built Green Certified homes to include high performance and healthy home features. In 2007, MRC joined the Department of Energy's Builders Challenge Program. Less than 1% of the market builders in the country work under this umbrella, which has a tag line “Research Towards Net Zero.” It charges its builders with striving to reach net zero while still being replicable and affordable. A recent name change better illustrates the goal: “DOE Zero Energy Ready Home.” With the help of the mechanical engineers that work with DOE on this program, Martha Rose Construction began trying different space and hot water heating combinations. The projects the company undertakes are small by development standards and they are custom designed for each site, even though they are sold on the speculative marketplace after completion. The goal was, and still is, to find the magic bullet for water and space heating that combines affordability w...