United States. The latest version of the ANSI/ASHRAE/IES Standard 90.1-2022, "Energy Efficiency Standard for Sites and Buildings Except Low-Rise Residential Buildings," includes expanded scope when it comes to construction sites and other major additions.
According to the organization ASHRAE, this update arose because they had identified some ambiguity in the standard, since it offered guidance on its applicability only of buildings and not of the sites or "sites", which is another space that is contemplated.
Don Brundage, chair of ASHRAE's Permanent Standard 90.1 Project Committee, said of the expanded information that examples include exterior and parking lighting, which if not supplied through the building's main electrical panel, did not previously fall within the scope of 90.1.
"The inclusion of the sites also clarifies that on-site renewables could count as credits for energy use throughout the building project, even if they are in a parking lot or other building space, not just within the building's footprint. We continue to improve efficiency and reduce energy consumption through updates to 90.1, meeting the needs of the design community and maintaining the relevance of 90.1 as the demand for energy and carbon reductions grows."
Other important additions
According to the official publication of ASHRAE, this update has as novelties a minimum prescriptive requirement for on-site renewable energy; an optional mechanical system performance path that allows HVAC system efficiency trade-offs based on the new Total System Performance Ratio (TSPR) metric; and new requirements to address the impacts of thermal bridges.
Likewise, Standard 90.1-2022, brings new energy credit requirements for a personalized approach to improve energy efficiency; a recent informative guide to using carbon emissions, site energy, or energy source as alternative performance metrics to the current energy cost metric; significant efficiency gains in IEER for commercial roofs and an unprecedented SEER2/HSPF2 metric for air-cooled heat pumps of size <65K.
Brundage explained that this modification "aligns the performance measurement of Standard 90.1 regulated products with the very similar and much larger market for single-phase <65K products, regulated as consumer products by the U.S. Department of Energy. In addition to operating with three-phase power instead of single-phase power, they are essentially the same products and should be evaluated using the same performance metric."
The Project Committee Chair also indicated that efficiency gains in IEER for commercial rooftop units provide substantial and cost-effective energy savings. In addition, he assured that, as an added benefit, they encourage variable speed operation, which helps improve dehumidification performance in humid climates.
"With these updates, industries and ASHRAE 90.1 have collaborated to further improve the efficiency of heating, ventilation and air conditioning equipment and processes used in buildings."
"These updates demonstrate that Standard 90.1 continues to work with industry stakeholders to drive improvements in the efficiency of HVAC equipment and processes used in buildings."
