Building Better: Advanced Energy Design Guides
When national labs and partnering organizations empower the commercial building industry with how-to guides for energy savings, the impact is clear.
After one of the strongest tornados on record hit Greensburg, Kansas, in the spring of 2007, 90% of the small rural community was destroyed. When it came time to assess the viability of the town after the fact, citizens focused not on the damage but on their vision of a "green" Greensburg, where the homes and businesses would be built far above standard. To make it official, local representatives wrote an ordinance requiring all public buildings in Greensburg be constructed to meet Leadership in Energy and Environmental Design (LEED) Platinum ratings from the U.S. Green Buildings Council (USGBC).
But before any structure can achieve a LEED designation, the design needs to incorporate a number of recommendations for achieving energy savings over the minimum code requirements. With the guidance of the Advanced Energy Design Guides (AEDGs), Greensburg constructed nine LEED Platinum commercial buildings, each using half or less of the energy of a standard building of its type.
In the Beginning
ASHRAE/IES Standard 90.1 has served as the benchmark for the energy efficient design of buildings since its inception in 1975. This code represents the baseline performance standard for new construction in the United States with the exception of low-rise residential buildings.
In 2002, Don Colliver, serving as the president for ASHRAE, called for the development of documents that identify excellent building practices in addition to minimum requirements. Four organizations—ASHRAE, the American Institute of Architects, the Illuminating Engineering Society of North America, and the USGBC—formed the Advanced Energy Design Guide (AEDG) steering committee to realize this vision. With the U.S. Department of Energy (DOE) acting as an ex-officio member of the committee and a major funding partner, this group became the driving force behind the development of user-friendly recommendations that go beyond code to achieve 30% energy savings compared to Standard 90.1-1999, and later, 50% savings over 90.1-2004.
Laying the Foundation
Two DOE national laboratories—NREL and Pacific Northwest National Laboratory (PNNL)—were brought in to provide robust energy modeling and life-cycle cost optimization capabilities. In addition, principal investigators from NREL and PNNL have served as the chair for the project committee, developing each guide in all cases but one.
Ten AEDGs have been produced to date, including six 30% guides and four 50% guides, which offer prescriptive approaches for achieving energy efficiency in newly constructed highway lodging, K-12 schools, small healthcare and hospitals, and commercial buildings like offices, retail locations, and warehouses. And they are being put to good use. In fact, the USD 422 Greensburg K-12 School was so successful in implementing energy efficient measures that it was selected as a case study for the AEDG for K-12 School Buildings: Achieving 50% Energy Savings Toward a Net Zero Energy Building.
More than 200,000 energy model runs are needed to develop a single guide. NREL and PNNL researchers use simulation tools such as EnergyPlus and OpenStudio to analyze a wide variety of possible directions, such as new low-energy technologies. They narrow the results down to an optimal set of measures for each building type within 16 representative climate zones.
Spreading the Word
As of December 2013, more than 500,000 copies of the AEDGs have been downloaded from the ASHRAE website and distributed to building industry professionals. After hitting the half-million circulation mark, Colliver characterized the success of the AEDGs as "a dream come true," and he's right.