design process study for the demonstration homes - Architectural ...

1.0 Introduction
As California’s population steadily rises—along with the number of new homes built to
meet the population’s needs—the state’s ongoing problems related to the cost and
production of electrical power to meet demand, and especially the summer peak demand,
continue to intensify. To help address the issue of growing energy use and demand, the
California Energy Commission under the Public Interest Energy Research (PIER) Program
has initiated a Zero Energy New Home (ZENHome) Program, which comprises four
projects, including the Utility-focused Market Model for Zero Energy New Homes
(Utility-focused Market Model for ZENHomes).
The overarching goal of the Utility-focused Market Model for ZENHomes project is to
develop a sustainable market model for building zero energy new homes. According to
the goals established by the California Energy Commission, ZENHome designs should
provide the following benefits at a cost premium of no more than $5,000:
• Electricity savings of 25% greater 2005 Title 24 standards
• 70% annual electric bill reduction for homeowners
• No more than 1 kW electricity demand during the summer peak
These goals are aggressive for production homes, and will require creative thinking about
the home as a system. However, it is important to realize that these are goals rather than
absolute requirements. The technology base for this business model includes innovative
and cost-effective combinations of energy efficiency devices coupled with on-site
electricity generation from photovoltaic (PV) panels to reduce both electrical demand and
consumption. (Note that while natural gas consumption is also reduced through these
strategies, gas savings per se are not within the scope of this project.)
The Utility-focused Market Model for ZENHomes also emphasizes developing the role of
the electric utility in creating a sustainable market for ZENHomes. To this end, the project
will evaluate the benefits that ZENHomes offer to utilities and create relationships
between utilities and other market participants to promote a sustainable market. A key
element to this process is the use of best practices from other high efficiency residential
design projects, such as the U.S. Department of Energy’s (DOE) Building America (BA)
Program, and assessing the elements that contributed to their successes and failures.
At the federal level, DOE, through its BA program, has been promoting the concept of
Zero Energy Homes (ZEH) for several years. Specifically, BA fosters energy efficient
technology development and helps builders construct ZEHs, defined as homes that offer
energy savings of at least 30% compared to the BA benchmark, which is less stringent
than the 2005 Title 24 standards. More details on the BA program and similar efforts are
provided below.
For reference, California established Title 24 Energy Efficiency Standards for Residential
and Nonresidential Buildings in 1978 in response to a legislative mandate to reduce
California's energy consumption. Referred to as Title 24, these standards set the
requirements for the energy efficiency of new residential construction in California and
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