Unlike ASHRAE Standard 90.1, which focuses on general commercial building efficiency, is tailored specifically for the unique, high-intensity energy needs of data centers. It provides:
The standard now gives better credit for the integration of renewable energy sources during the design phase.
If you are looking for the "upd" (update), you are likely interested in the changes between the 2016, 2019, and 2022 versions. ashrae 904 pdf upd
New ELC segment calculation breakpoints are now required at 25%, 50%, 75%, and 100% design load, aligning electrical efficiency metrics more closely with real-world operating conditions.
A composite efficiency metric based on worst-case losses across the power chain segments. Accessing the PDF & Addenda As a standard under continuous maintenance Unlike ASHRAE Standard 90
Official copies and dynamic supplements are maintained directly via the ASHRAE Bookstore. The framework's core metrics, compliance paths, and latest environmental expansions dictate modern green data center engineering. Core Structure of ASHRAE Standard 90.4
: The "incoming service segment" was removed from ELC calculations because designers often have limited control over public utility equipment. Renewable Energy Credits New ELC segment calculation breakpoints are now required
Recent addenda place greater emphasis on accounting for renewable energy sources and their impact on the overall facility energy calculation. How to Access Official PDFs and Track Updates
