DOE Reaches 50% Milestone toward Commercial Zero-Energy Buildings

November 03, 2008

The U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) have released the first technical support documents to show 50% energy savings in commercial retail buildings. The two reports provide recommendations on how to achieve 50% energy savings over the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Standard 90.1-2004 in grocery stores and medium-sized retail buildings.

Conducted by NREL's Commercial Buildings team, under the direction of DOE's Building Technologies Program, the studies support DOE's goal of producing market-ready, net-zero energy commercial buildings by 2025. They follow the August launch of DOE's Net-Zero Energy Commercial Building Initiative (the umbrella initiative of the net-zero energy goal) and the National Laboratory Collaborative on Building Technologies, which focuses scientific expertise and resources of five national laboratories toward reaching the goal. NREL is one of the laboratories in the collaborative.

The reports found that achieving 50% energy savings is possible for medium-sized retail buildings with plug load levels no greater than 1.76 W/sq. ft. (18.9 W/sq. m.) and for grocery stores in each climate zone in the United States. According to the reports, reaching 50% is a positive return on investment at today's energy prices and can be met without photovoltaic electricity generation.

DOE commissions technical support documents to describe the assumptions, methodologies, and analyses used to achieve certain levels of energy performance. In many cases, the documents are the basis for Advanced Energy Design Guides (AEDGs)—"how to" guides that show how to achieve above-code exemplary energy performance for buildings. AEDGs target architects, engineers, and other design practitioners and demonstrate that a pathway to energy savings exists today with available technology.

The ASHRAE AEDGs are developed by ASHRAE, DOE, the American Institute of Architects, the Illuminating Engineering Society of North America, and the U.S. Green Building Council. To date, four AEDGs have been published and all have targeted 30% energy savings:

• The ASHRAE Advanced Energy Design Guide for Small Office Buildings—Office Buildings up to 20,000 sq.ft.²
• The ASHRAE Advanced Energy Design Guide for Small Retail Buildings—Retail Spaces up to 20,000 sq.ft.²
• The ASHRAE Advanced Energy Design Guide for K-12 School Buildings—Elementary, Middle, and High School Buildings
• The ASHRAE 30% Advanced Energy Design Guide for Small Warehouses and Self-Storage Buildings—Warehouses up to 50,000 ft.² and self-storage buildings that use unitary heating and air-conditioning.

In addition to the ASHRAE design guides, the results of these studies will be shared with DOE's Retailer Energy Alliance, an alliance of leading retailers dedicated to reducing the energy use and environmental footprint of retail buildings.

The technical support documents are available on the NREL Web site. The following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

• Technical Support Document: Development of the Advanced Energy Design Guide for Medium Box Retail—50% Energy Savings (PDF 4.3 MB)
• Technical Support Document: Development of the Advanced Energy Design Guide for Grocery Stores—50% Energy Savings (PDF 2.7 MB)