ASHRAE 90.1-2010 mandatory requirement 8.4.2 Automatic Receptacle Control applies to 125 Volt receptacles in private offices, open offices, and computer classrooms. Are there any cases where exceptions to these mandatory requirements will be allowed?
The project team is requesting clarification regarding how to model spaces where mandatory ASHRAE 90.1 receptacle controls are not implemented. Projects using one of the following two compliance paths are exempt from the receptacle control requirements:
1. Path 1: Projects Using Option 1. Whole Building Energy Simulation may model a penalty in the Proposed model for the spaces where mandatory ASHRAE 90.1 receptacle controls are not implemented. The following modeling requirements apply:
• The receptacle power density modeled for these spaces shall be the greater of 0.75 Watts per square foot (8.1 Watts per square meter) or the design coincident peak receptacle power density (if known).
• The receptacle schedule modeled in the Baseline for these spaces shall have a minimum Equivalent Full Load Hours of operation no less than:
o The ASHRAE 90.1-2010 User’s Manual default schedule for office occupancy (2,920 Equivalent Full Load Hours per year)
OR
o 120% of the occupied hours of operation for the facility
OR
o Detailed justification shall be provided supporting an alternate schedule.
• The Proposed model shall include either a 20% increase in the receptacle power density for these spaces OR a 20% increase in the scheduled receptacle Equivalent Full Load Hours of Operation versus the Baseline model.
2. Path 2: Projects must demonstrate that the project has implemented efficiency measures that will achieve an equal or greater reduction in receptacle energy consumption, and will persist for a similar timeframe to those achieved by ASHRAE 90.1-2010 Section 8.4.2. It is recommended that a Credit Interpretation Request be submitted when pursuing this approach. The project must provide documentation regarding the receptacle equipment controls that will be implemented for the project; and must provide justification supporting the claim that the savings over the life of the efficiency measure will be similar to those anticipated for a project compliant with Section 90.1-2010 Section 8.4.2. Note: The baseline and proposed receptacle energy consumption for these spaces must be modeled identically if using this approach; the project is not eligible for any further receptacle savings in these spaces using the Exceptional Calculation Method.
Update 3/1/2024:
This LEED Interpretation is not applicable to projects subject to the LEED v4 2024 update because the allowance is directly incorporated into the v4 2024 update Reference Guide content for EAp Minimum Energy Performance.
Update 4/21/2023:
Note, the additional requirements published on 11/9/2020 for v4.1 projects using Path 1 are incorporated into the v4 Reference Guide content for EAp Minimum Energy Performance.
Update 11/9/2020:
Where ASHRAE 90.1 receptacle controls are not implemented in accordance with Section 8.4.2 mandatory requirements, LEED v4.1 projects may apply either Path 1 or Path 2, subject to the following requirements for Path 1:
• Path 1: LEED v4.1 projects Using the Appendix G Performance Rating Method may model a penalty in the energy model. The following modeling requirements apply:
o The Proposed receptacle power density modeled for these spaces shall be the greater of 0.75 Watts per square foot (8.1 Watts per square meter) or the design coincident peak receptacle power density (if known)
o The receptacle schedule modeled in the Proposed design for these spaces shall have a minimum Equivalent Full Load Hours of operation no less than: the ASHRAE 90.1-2016 User’s Manual default schedule for office occupancy (2,920 Equivalent Full Load Hours per year); or 120% of the occupied hours of operation for the facility; or detailed justification shall be provided supporting an alternate schedule.
o The Baseline model shall include either a 20% decrease in the receptacle power density for these spaces OR a 20% decrease in the scheduled receptacle Equivalent Full Load Hours of Operation versus the Proposed model.