Zero Energy Homes (ZEH) are designed to use zero net energy from the utility grid. The concept is simple—couple the maximum possible building energy efficiencies with the best available renewable energy resources so as to achieve zero energy. The Home Energy Rating System (HERS) index determines the likelihood of a home performing at zero energy for a typical occupant. A typical existing home might have a HERS index of 120 – 140, and a typical new home around 85 to 100. A score of 70 is projected to use 30% less energy than one at 100; A score of zero means a net zero energy bill. FSEC’s first near Zero Energy Home was built in Lakeland, Florida in 1998.
There is now a new generation of Zero Energy Homes being designed and constructed around the country, many with technical support from Building America teams under the sponsorship of the U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) in Golden, CO.
A primary aim in each of these projects is to collect detailed performance data that will allow refinement of the approach for integrating energy efficiency measures with photovoltaic (PV) and solar thermal systems. FSEC is collecting ZEH data from the homes in the case studies listed below.
Years of Research: 1998 – Present
Sponsored by: U.S. Department of Energy, National Renewable Energy Laboratory
Constructing high performance homes is the goal of the U.S. Department of Energy’s Building America research program. Many of the Building America research teams work directly with builders to construct zero energy or zero energy-ready homes. Publication
In 1998, FSEC began its Zero Energy Homes research program in collaboration with the City of Lakeland municipal utility and builder Rick Strawbridge. Two homes were constructed and tested on a side-by-side basis for more than a year. Details & Data | Publication
Building America research partners have demonstrated that high-performance homes can boost sales. It requires a tailored, easy-to-understand marketing campaign, though. LifeStyle Homes focuses on the high performance benefits—not the technical details behind them. Publication
LifeStyle Homes completed its first zero energy home in August 2010. Final inspection and testing of the home resulted in an impressive HERS Index of -6, exceeding the Builders Challenge level of performance. Publication
COMPILATION OF LESSONS LEARNED From Four Near Zero Energy Homes in Florida
The four homes discussed in this study represent the three major forms of residential construction in Florida: site-built wood frame, site-built concrete block, and manufactured or modular housing. All of the instrumented homes provided data on electrical consumption and generation, interior conditions, and basic weather parameters. By examining the energy data, audited miscellaneous electrical loads, and occupancy of these homes, the study seeks to identify sources of discrepancy in reaching performance goals. Publication
This near zero energy home in Gainesville, Florida, features all ENERGY STAR-rated appliances. It has a 120-gallon solar hot water system. It is a 1,772 sq ft, single story, three-bedroom/two-bath home with a preliminary HERS rating of 29. Occupied by two people.
Publication | Data
This factory-built modular home near Panama City is the first home in Florida to achieve a LEED for Homes platinum rating. Promise Land Builders built the house. It is a two-story three-bedroom/two-bath home with 1,371 sq ft of living space and a HERS rating of 26. Occupied by one person.
Details | Data | Publication
- Comprehensive Modeling of Optimal Paths to Reach Nearly Zero Energy Buildings (nZEBs) for New Constructions in Europe