Consumers buying or building homes are increasingly emphasizing energy-efficient performance as one of a home’s most desirable features, yielding lower annual operating costs and reducing their household carbon footprints. But comparing the energy efficiency of two homes has always been challenging, and it only becomes more difficult when green-certified homes are thrown into the mix. An apples-to-apples comparison between older existing homes and newer homes presents an even greater conundrum. Enter the home energy performance labeling concept.
Over the past several years, there has been a push for the development of a standardized method for evaluating and communicating home performance in much the same way car fuel efficiency is rated. Building performance auditing and labeling standards are already in use in Europe and Australia, and a similar method recently was launched in Oregon and currently is being piloted in Seattle. According to a report released recently by the Northeast Energy Efficiency Partnerships (NEEP), public policies requiring the rating and disclosure of buildings’ and homes’ energy use can help shift markets toward valuing energy efficiency, as well as create jobs and reduce greenhouse gas emissions. (Click for information on the report.)
Many Oregon builders have been choosing to have their homes audited under the voluntary Energy Performance Score (EPS) program for new homes, which was developed by the green building organization Earth Advantage Institute with Energy Trust of Oregon, a nonprofit energy efficiency organization serving the state’s utility customers.
Comparing Apples to Apples
The Earth Advantage/Energy Trust EPS measures home energy usage and provides a common metric that builders, homeowners, realtors, mortgage lenders, appraisers, and code officials can all use for conveying information about a home’s annual energy usage, energy costs, and carbon emissions, according to David Heslam, remodeling and EPS program manager. In addition to providing actual performance data, a home’s EPS report also predicts energy use and carbon emissions after specific recommended upgrades are made.
While the HERS index (Home Energy Rating Standards) is commonly used in the industry to calculate home energy consumption, it provides only a relative performance score: the home as built compared to the performance of the same home if it was built only to minimum code requirements. The HERS index isn’t very useful for comparing one home’s performance to another’s.
“The EPS allows homeowners to make a comparison from one home to another,” Heslam says. “From an economic standpoint, it’s providing more information to the marketplace, so the market can then make better decisions about energy usage.”
