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LEED v4.1
Data Centers – NC
Energy and Atmosphere
Optimize Energy Performance

LEED CREDIT

Data-Centers-NC-v4.1 EAc2: Optimize Energy Performance 1-18 points

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Intent

To achieve increasing levels of energy performance beyond the prerequisite standard to reduce environmental and economic harms associated with excessive energy use.

Requirements

Establish an energy performance target no later than the schematic design phase. The target must be established using one of the following metrics:

  • kBtu per square foot-year (kWh per square meter-year) of site energy use
  • kBtu per square foot-year (kWh per square meter-year) of source energy use
  • pounds per square foot-year (Kg per square meter-year) of greenhouse gas emissions
  • energy cost per square foot-year (cost per square meter-year)
Analyze efficiency measures during the design process and account for the results in design decision making. Use energy simulation of efficiency opportunities, past energy simulation analyses for similar buildings, or published data (e.g., Advanced Energy Design Guides) from analyses for similar buildings. Analyze efficiency measures, focusing on load reduction and HVAC-related strategies (passive measures are acceptable) appropriate for the facility. Project potential energy savings and holistic project cost implications related to all affected systems. Choose one of the options below.
Option 1. Energy Performance Compliance (1–18 points except Schools and Healthcare, 1–16 points Schools, 1–20 points Healthcare)
Demonstrate a Performance Cost Index (PCI)1 below the Performance Cost Index Target (PCIt) calculated in accordance with Section 4.2.1.1 of ANSI/ASHRAE/IESNA Standard 90.1-2016, Appendix G, Table 4.2.1.1. For mixed use buildings, the required PCI shall be calculated by using an area weighted average of the building types. Calculate the PCI, PCIt, and percentage improvement using metrics of cost and greenhouse gas (GHG) emissions. For each energy source serving the building, the GHG emission factors must be identical for the Baseline and Proposed building models. LEED points are calculated based on the project percent improvement PCI below the PCIt using metrics of cost and GHG emissions. Total points have been divided equally between the metrics of energy cost and greenhouse gas emissions. Points are awarded according to Table 1 and Table 2. For project percent improvement for the cost metric, on-site renewable energy may be subtracted from proposed energy cost prior to calculating proposed building performance per ASHRAE Standard 90.1-2016 Section G 2.4.1.
Table 1. Points for percentage improvement in energy performance – % Cost PCI below PCIt (1-9 points NC and CS, 1-8 points Schools, 1-10 points Healthcare)
New Construction Healthcare, Major Renovation, CS Points BD+C (except Schools, Healthcare) Points Healthcare Points Schools
5% 2% 1 1 1
10% 5% 2 2 2
15% 10% 3 3 3
20% 15% 4 4 4
25% 20% 5 5 5
30% 25% 6 6 6
35% 30% 7 7 7
40% 35% 8 8
45% 40% 9 9 8
50% 45% EP 10 EP
50% EP
*BD+C projects except Data Centers with unregulated energy cost exceeding 50% of the total proposed building energy cost, and BD+C: Data Centers projects with at least 40% gross colocation data center area may use the “Healthcare, Major Renovation, CS” column in lieu of the “New Construction” column. On-site renewable energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance per ASHRAE Standard 90.1-2016 Section G 2.4.1. New off-site renewable energy as defined in EA credit Renewable Energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance.
Table 2. Points for percentage improvement in energy performance – % Greenhouse Gas Emissions PCI below PCIt (1-9 points NC, 1-8 points Schools, 1-10 points Healthcare)
New Construction Healthcare, Major Renovation, CS, Points BD+C (except Schools, Healthcare) Points Healthcare Points Schools
5% 2% 1 1 1
10% 5% 2 2 2
16% 10% 3 3 3
24% 16% 4 4 4
32% 24% 5 5 5
40% 32% 6 6 6
50% 40% 7 7 7
65% 50% 8 8
80% 65% 9 9 8
100% 80% EP 10 EP
100% EP
*BD+C projects except Data Centers with unregulated energy cost exceeding 50% of the total proposed building energy cost, and BD+C: Data Centers projects with at least 40% gross colocation data center area may use the “Healthcare, Major Renovation, CS” column in lieu of the “New Construction” column.
DATA CENTERS ONLY
In addition to the requirements above, analyze efficiency measures focused on IT load reduction and HVAC-related strategies. Collocated data centers may use the CS percentage improvement thresholds in lieu of NC thresholds to earn points in Table 1 and Table 2. OR
Option 2. Prescriptive Compliance: ASHRAE Advanced Energy Design Guide (1–6 points, 1-4 points CS)
To be eligible for Option 2, projects must meet the Scope requirements of the applicable AEDGs (or combination of AEDGs for mixed use), and projects must use the ASHRAE 90.1-2016 Prescriptive compliance path in EA Prerequisite Minimum Energy Performance. Implement and document compliance with the applicable recommendations and standards in Chapter 4, Design Strategies and Recommendations by Climate Zone, for the appropriate ASHRAE 50% Advanced Energy Design Guide and climate zone. ASHRAE 50% Advanced Energy Design Guide for Small to Medium Office Buildings
  • Building envelope: roofs, walls, floors, slabs, doors, continuous air barriers, and vertical fenestration (1 point, 2 points CS)
  • Interior and exterior lighting, including daylighting and interior finishes (1 point). CS: Minimum 20% of building area must have a complete lighting design.
  • Plug loads, including equipment and controls (2 points, 0 points CS)
  • HVAC Systems and Controls (2 points, 1 point CS). CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume.
ASHRAE 50% Advanced Energy Design Guide for Medium to Large Box Retail Buildings
  • Building envelope: roofs, walls, floors, slabs, doors, vestibules and fenestration – all orientations (1 point, 2 points CS)
  • Interior and exterior lighting, excluding lighting power density for sales floor (1 point). CS: Minimum 20% of building area must have a complete lighting design
  • Additional interior lighting for sales floor (1 point, 0 points CS)
  • Plug loads, including equipment choices and controls (1 point, 0 points CS)
  • HVAC efficiency and control requirements (2 points, 1 point CS). CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume)
ASHRAE 50% Advanced Energy Design Guide for K–12 School Buildings (Not applicable for CS)
  • Building envelope: roofs, walls, floors, slabs, doors and vertical fenestration (1 point)
  • Interior and exterior lighting, including daylighting and interior finishes (1 point)
  • Plug loads, including equipment choices, controls, and kitchen equipment (2 points)
  • HVAC efficiency and control requirements (2 points)
ASHRAE 50% Advanced Energy Design Guide for Large Hospitals
  • Building envelope: roofs, walls, floors, slabs, doors, vestibules, continuous air barriers, and vertical fenestration (1 point, 2 points CS)
  • Interior and exterior lighting, including daylighting (form or nonform driven) and interior finishes (1 point). CS: Minimum 20% of building area must have a complete lighting design
  • Plug loads, including equipment choices, controls, and kitchen equipment (1 point, 0 points CS)
  • HVAC and Service Water Heating Systems and Equipment (2 points) (1 point CS. CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume)
ASHRAE 50% Advanced Energy Design Guide for Grocery Stores
  • Building envelope: roofs, walls, floors, slabs, doors, vestibules, continuous air barriers, and vertical fenestration (1 point) (2 points – CS)
  • Interior and exterior lighting, including sales floor (1 points)
  • Refrigeration, Plug, and Process loads, including equipment choices and controls (2 points)(0 points CS)
  • HVAC efficiency and control requirements (1 point) (1 point CS. CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume)
OPTION 3. Systems Optimization (1-4 points)
To be eligible for Option 3, projects must use the ASHRAE 90.1-2016 Prescriptive compliance path in EA Prerequisite Minimum Energy Performance, and must not have more than 2,000 square feet of data center space, laboratory space, or manufacturing space. Demonstrate an improvement beyond ASHRAE/ASHRAE/IESNA Standard 90.1–2016, with errata, for the following systems: Interior and Exterior Lighting; Daylight controls; Building envelope; HVAC and service water heating equipment efficiency; and Equipment and appliances. Each three strategies selected earns 1 point (For Core & Shell lighting and HVAC efficiency measures, the project scope of work must include a complete design for at least 20% of the building area to qualify).
  • Interior and Exterior Lighting:
    • 15% lighting power reduction
    • 30% lighting power reduction
    • 45% lighting power reduction
  • Daylight controls: Install daylight-responsive controls for a given percentage of connected lighting load (lighting in non-regularly occupied space with occupant sensor controls may be excluded from connected lighting load).
    • 35%
    • 70%
  • Building envelope:
    • Climate Zones 1 – 2:
      • Thermal Mass Enclosure: More than 70% of opaque above-grade wall area meets ASHRAE 90.1-2016 definition for “mass wall”; and more than 70% of floor area meets ASHRAE 90.1-2016 definition for “mass floor”
      • 25% Envelope UA reduction
      • 50% SHGC reduction (including window shade factors)
    • Climate Zones 3 – 8:
  • HVAC and Service Water Heating Equipment Efficiency:
    • Reduction in total fan power allowance of:
      • 15%
      • 30%
      • 45%
    • Improvement in efficiency for at least 75% of the combined cooling, heating, and service water heating capacity
      • 10%
      • 20%
      • 30%
      Electric resistance heating except heat pump auxiliary heat must be included in total capacity.
  • Equipment and Appliances: Install a percentage (by rated power) of eligible equipment and appliances meeting the following requirements:
    • ENERGY STAR equipment including appliances, office equipment, electronics, and commercial food service equipment (lighting and building envelope products are excluded from this credit). (Electronic Product Environmental Assessment Tool (EPEAT) equipment may be used in lieu of Energy Star equipment where applicable).
    • Prescriptive commercial kitchen and refrigeration equipment requirements listed in Appendix 3, Table 1.
    The project scope of work must include at least 0.25 Watts per square foot of eligible equipment to apply this strategy.
Percent of Eligible Equipment Installed by Rated Power:
  • 20%
  • 40%
  • 60%
  • 80%
  • 100%
OR
OPTION 4. DATA CENTERS ONLY– SYSTEM OPTIMIZATION (1 TO 3 POINTS)
Calculate an Overall Systems Design Value as the sum of the maximum design Mechanical Load Component (MLC) and maximum design Electrical Load Component (ELC) in accordance with ASHRAE 90.4-2016 Section 6.2, Section 8.2, and Section 11. Document that the Overall Systems Design value is less than the Maximum Overall Systems Value by:
  • 10% (1 point)
  • 20% (2 points)
  • 30% (3 points)
*If the electrical system design is incomplete, the design values shall be assumed to match the values in Table 8.2.1.1 and 8.2.1.2. Collocated data centers: document that the Overall Systems Design value is less than the Maximum Overall Systems Value by:
  • 6% (1 point)
  • 12% (2 points)
  • 18% (3 points)
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Addenda

4/9/2021Updated: 6/10/2021
Form Update
Description of change:
Update the table for "Daylight Controls" in the form as described below.

Changes to be made to Table: Lighting Controls:

1. Delete the column "Sensor Type"

2. Delete the column "Load with Occupant Sensors (W)"

3. Revise the rows in the table that are automatically calculated (below the row(s) where the user reports "Space type" and "Load with Daylight Sensors") to the following:

• Total connected lighting load (Watts)
• Allowable exclusion: Connected lighting power for non-regularly occupied space with occupant sensor controls (Watts)
• Connected lighting load with allowable exclusion (Watts)
• Percent connected load with daylighting sensors

4. The value for the row "Total connected lighting load (Watts)" does not change - it remains the "Total" value from Table: Lighting power summary in the form.

5. The value for the row "Allowable exclusion: Connected lighting power for non-regularly occupied space with occupant sensor controls (Watts)" is entered by the user.

6. the value for the row "Connected lighting load with allowable exclusion (Watts)"
= Total Connected lighting load – Allowable Exclusion

7. The value for the row "percent connected load with daylighting sensors" = total summed power with daylight sensors divided by Calculated value for connected lighting load with allowable exclusion(s) above.
Campus Applicable
No
Internationally Applicable:
No
4/9/2021Updated: 4/19/2021
Rating System Correction
Description of change:
EA prerequisite Minimum Energy Performance:
- revise Intent to read as follows: "To promote resilience and reduce the environmental and economic harms of excessive energy use that disproportionately impact frontline communities by achieving a minimum level of energy efficiency for the building and its systems."

EA credit Optimize Energy Performance:
- revise Intent to read as follows: "To achieve increasing levels of energy performance beyond the prerequisite standard to reduce environmental and economic harms associated with excessive energy use that disproportionately impact frontline communities."
Campus Applicable
No
Internationally Applicable:
No
7/25/2019Updated: 3/1/2021
Rating System Correction
Description of change:
IP credit Integrative Process

Under the heading "Energy-Related Systems" add the following text:
"Establish an energy performance target no later than the schematic design phase. The target must be established using one of the following metrics:
• kBtu per square foot-year (kWh per square meter-year) of site energy use
• kBtu per square foot-year (kWh per square meter-year) of source energy use
• pounds per square foot-year (Kg per square meter-year) of greenhouse gas emissions
• energy cost per square foot-year (cost per square meter-year)"

EA credit Optimize Energy Performance

Delete the following requirement:
"Establish an energy performance target no later than the schematic design phase. The target must be established using one of the following metrics:
• kBtu per square foot-year (kWh per square meter-year) of site energy use
• kBtu per square foot-year (kWh per square meter-year) of source energy use
• pounds per square foot-year (Kg per square meter-year) of greenhouse gas emissions
• energy cost per square foot-year (cost per square meter-year)"

EA credit Optimize Energy Performance, Step by Step:

Delete bullet point "Establish an energy use intensity (EUI) target no later than schematic design using one of the required metrics noted".
Campus Applicable
No
Internationally Applicable:
No
7/25/2019Updated: 3/1/2021
Reference Guide Correction
Description of change:
IP credit Integrative Process

Under the heading "Energy-Related Systems" add the following text:
"Establish an energy performance target no later than the schematic design phase. The target must be established using one of the following metrics:
• kBtu per square foot-year (kWh per square meter-year) of site energy use
• kBtu per square foot-year (kWh per square meter-year) of source energy use
• pounds per square foot-year (Kg per square meter-year) of greenhouse gas emissions
• energy cost per square foot-year (cost per square meter-year)"

EA credit Optimize Energy Performance

Delete the following requirement:
"Establish an energy performance target no later than the schematic design phase. The target must be established using one of the following metrics:
• kBtu per square foot-year (kWh per square meter-year) of site energy use
• kBtu per square foot-year (kWh per square meter-year) of source energy use
• pounds per square foot-year (Kg per square meter-year) of greenhouse gas emissions
• energy cost per square foot-year (cost per square meter-year)"

EA credit Optimize Energy Performance, Step by Step:

Delete bullet point "Establish an energy use intensity (EUI) target no later than schematic design using one of the required metrics noted".
Campus Applicable
No
Internationally Applicable:
No
11/9/2020Updated: 2/3/2021
Form Update
Description of change:
Updated to align with v4.1 November 2020 Addenda
Campus Applicable
No
Internationally Applicable:
No
11/9/2020Updated: 12/7/2020
Regional ACP
Description of change:
See the Resource Library for full ACP requirements and documentation.
Campus Applicable
No
Internationally Applicable:
No
11/10/2020Updated: 11/25/2020
Rating System Correction
Description of change:
In the Further Explanation section "Applying Renewable Energy Savings", in the sentence that begins "For the metric of greenhouse gas emissions...", replace the word "new" with "Tier 2".
Campus Applicable
No
Internationally Applicable:
No
11/10/2020Updated: 11/25/2020
Rating System Correction
Description of change:
Option 1

1. Below Table 1 Points for percentage improvement in energy performance – % Cost PCI below PCIt, in the sentence that reads "New Tier 2 off-site renewable energy as...", replace the word "New" with "Tier 2".

Option 2

2. Delete all three instances of the sentence "CS: Minimum 20% of building area must have a complete lighting design."

3. Delete all four instances of the sentence "CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume"

Option 3

4. Revise Option 3 title to read as follows: "Option 3. Systems Optimization (1-6 points)"

5. Delete sentence "Each three strategies earn 1 point (For Core & Shell lighting and HVAC efficiency measures, the project scope of work must include a complete design for at least 20% of the building area to qualify)"

6. Below the sentence "Demonstrate an improvement beyond ASHRAE/ASHRAE/IESNA Standard 90.1–2016, with errata, for the following systems:" add the following sentence:
"Use any combination of the strategies in any or all of the categories below, for a maximum of up to 6 points."

7. Interior and Exterior Lighting: At the end of each the three identified % lighting power reduction thresholds, add "(1 point)"

8. Daylight controls: Replace "35%" with "40% (1 point)". Delete the "70%" threshold.

9. Building envelope: next to each heading "Climate Zones 1 – 2:" and "Climate Zones 3 - 8:" add the sentence "Achieve 2 of the 3 strategies below for 1 point."

10. HVAC and Service Water Heating Equipment Efficiency:
- Reduction in total fan power allowance: replace the 15% threshold with the following text: "20% (1 point) and delete the "30%" and "45%"
- Next to the 20% threshold, add "(1 point)" and delete the "10%" and "30%"

11. Percent of Eligible Equipment Installed by Rated Power: replace "20%" with "75% (1 point)" and delete all other thresholds in the bulleted list
Campus Applicable
No
Internationally Applicable:
No
7/25/2019Updated: 7/30/2019
Reference Guide Correction
Description of change:
After the "Referenced Standards" section of the Further Explanation section, add a new section "Exemplary Performance" to the guidance for the rating systems shown below:

BD+C:
"Exemplary Performance:
Option 1. Achieve 55% savings in the cost metric, achieve 100% savings in the greenhouse gas emissions metric, or use actual utility rates when calculating cost savings and hourly greenhouse gas emissions factors when calculating greenhouse gas emissions savings."

ID+C:
"Exemplary Performance:
Option 1. Achieve 36% savings in the cost metric, achieve 100% savings in the greenhouse gas emissions metric, or use actual utility rates when calculating cost savings and hourly greenhouse gas emissions factors when calculating greenhouse gas emissions savings."
Campus Applicable
No
Internationally Applicable:
No
7/25/2019Updated: 7/30/2019
Reference Guide Correction
Description of change:
Add the following reference to the list of Referenced Standards, including the direct link to the resource:

Developing Performance Cost Index Targets for ASHRAE Standard 90.1 Appendix G - Performance Rating Method
https://www.pnnl.gov/main/publications/external/technical_reports/PNNL-2...
Campus Applicable
No
Internationally Applicable:
No
7/25/2019Updated: 7/29/2019
Rating System Correction
Description of change:
Under Table 1. Points for percentage improvement in energy performance, and Table 2. Points for percentage improvement in energy performance, include the following footnote for Column: “Points BD+C (except Schools, Healthcare)”

BD+C projects except Data Centers with unregulated energy cost exceeding 50% of the total proposed building energy cost, and BD+C: Data Centers projects with at least 40% gross colocation data center area may use the “Healthcare, Major Renovation, CS” column in lieu of the “New Construction” column.
Campus Applicable
No
Internationally Applicable:
Yes
4/9/2019Updated: 4/9/2019
Rating System Correction
Description of change:
Revise the language below Data Centers Only to read as follows: "In addition to the requirements above, analyze efficiency measures focused on IT load reduction and HVAC-related strategies. Collocated data centers may use the CS percentage improvement thresholds in lieu of NC thresholds to earn points in Table 1 and Table 2."
Campus Applicable
No
Internationally Applicable:
Yes
4/9/2019
LEED Interpretation
Inquiry:

Our project is subject to ASHRAE Standard 90.1-2013 for code compliance. To pursue Option 1: Energy Performance Compliance in LEED v4.1 BD+C, is there a methodology for documenting additional energy performance for LEED v4.1 projects regulated by ASHRAE Standard 90.1-2013?

Ruling:

Yes, projects applying Option 1: Energy Performance Compliance, and regulated by ASHRAE Standard 90.1-2013 or IECC 2015 may document achievement of LEED v4.1 BD+C EA Prerequisite Minimum Energy Performance and EA Credit Optimize Energy Performance as described below:
Comply with all mandatory provisions of ASHRAE Standard 90.1-2013 or IECC 2015.

AND

Demonstrate a Percentage improvement in the Proposed Building Performance beyond the Baseline Building performance in accordance with ANSI/ASHRAE/IESNA Standard 90.1-2013, Appendix G.

Calculate the Baseline Building Performance, Proposed Building Performance, and Percentage Improvement using metrics of cost and greenhouse gas (GHG) emissions. For each energy source serving the building, the GHG emission factors must be identical for the Baseline and Proposed building models.

The LEED prerequisite Percentage Improvement requirements may be demonstrated either using metrics of cost from Table 1 or greenhouse gas (GHG) emissions from Table 2. LEED points are calculated based on the project percent improvement for cost and GHG emissions. Total points have been divided equally between the metrics of energy cost and greenhouse gas emissions. Points are awarded according to Table 1 and Table 2.

For project percent improvement for the cost metric, on-site renewable energy may be subtracted from proposed energy cost prior to calculating proposed building performance per ASHRAE Standard 90.1-2013 Section G 2.4.1.

Table 1. Points for percentage improvement in energy performance – Cost (1-9 points NC and CS, 1-8 points Schools, 1-10 points Healthcare)

New
Construction
(except
Healthcare,
Schools,
Multifamily
Residential)
Healthcare,
Major
Renovation,
CS

Schools
Points
BD+C
(except
Schools,
Healthcare)
Points
Healthcare
Points
Schools

7%
3%
15%
Prerequisite
Prerequisite
Prerequisite

12%
5%
20%
1
1
1

17%
8%
25%
2
2
2

22%
13%
30%
3
3
3

27%
18%
35%
4
4
4

32%
23%
40%
5
5
5

37%
28%
45%
6
6
6

42%
33%
50%
7
7
7

47%
38%
-
8
8
-

52%
43%
60%
9
9
8

57%
48%
65%
EP
10
EP

-
53%
-
-
EP
-

On-site renewable energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance per ASHRAE Standard 90.1-2013 Section G 2.4.1. New off-site renewable energy as defined in EA credit Renewable Energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance.

Table 2. Points for percentage improvement in energy performance – Greenhouse Gas Emissions (1-9 points NC, 1-8 points Schools, 1-10 points Healthcare)

New Construction (except Healthcare, Schools, Multifamily Residential)
Healthcare, Major Renovation, CS
Schools
Points BD+C (except Schools, Healthcare)
Points Healthcare
Points Schools

7%
3%
15%
Prerequisite
Prerequisite
Prerequisite

12%
5%
20%
1
1
1

17%
8%
25%
2
2
2

23%
13%
31%
3
3
3

31%
19%
37%
4
4
4

39%
27%
43%
5
5
5

47%
35%
50%
6
6
6

55%
43%
60%
7
7
7

65%
50%
-
8
8
-

80%
65%
80%
9
9
8

100%
80%
100%
EP
10
EP

-
100%
-
-
EP
-

Campus Applicable
No
Internationally Applicable:
No
10/14/2019
LEED Interpretation
Inquiry:

Data centers have large, complex energy use that is not as widely understood or regulated from an energy code perspective. Traditionally, the ASHRAE 90.1 standard has not provided any guidance on what the minimum performance should be for electrical distribution systems for data centers. Recently, ASHRAE published the 90.4-2016 standard that provides guidance and maximum electrical losses for two different size data centers (less than and greater than 200 kW) and for three different components (or segments) of the electrical distribution system (Incoming Electrical Service, UPS Segment, and ITS Distribution Segment). The standard also creates an overall energy efficiency metric, the Electrical Loss Component that is the composite of the efficiencies of each of the three components defined.

We are seeking confirmation that ASHRAE 90.4-2016 can be used to establish a baseline electrical system efficiency for data centers for the electrical distribution system. If approved, the process for documenting the Proposed Case electrical system efficiency would be to calculate each of the three component efficiencies, per ASHRAE 90.4-2016, and provide supporting documentation that outlines these calculations and includes back-up documentation for any equipment efficiencies used in that calculation. The resulting baseline and proposed case efficiencies and energy savings associated with the proposed electrical system design could then be summarized in a report or input into the USGBC Data Center Calculator to communicate the findings to the GBCI and review team.

Ruling:

The applicant proposes to use the Electrical Loss Component (ELC) calculated in accordance with ANSI/ASHRAE Standard 90.4-2016, Section 8 in lieu of the Electrical System Efficiency calculated in the LEED Data Center Calculator. In ASHRAE Standard 90.4-2016, the ELC is calculated based on maximum loads at two separate IT loads (100% and 50% of IT design load for Single Feed UPS; and 50% and 25% of IT design load for Dual Feed UPS).

The proposed approach is acceptable. However, if averaging the energy results for the project at 100% IT design load with the energy results for the project at startup IT loads, the ELC may only be used in conjunction with the 100% IT design load energy model, or with a startup IT load that represents 50% of IT design load for single feed UPS or no UPS configurations, or 25% of IT design load for active dual feed UPS systems. The documentation must specifically indicate the relevant maximum Electrical Loss / Efficiency Total from Table 8.2.1.1 or 8.2.1.2 of the Standard, and must be sufficient to confirm that the Electrical System Efficiency has been determined consistent with Standard 90.4:

a. Provide submittal drawings consistent with the requirements of Section 8.4.1.
b. Provide ELC calculations with the same level of detail as is provided in the Examples provided in Appendix C.
c. UPS Segment Efficiency: Losses shall be based on manufacturer’s stated losses based on manufacturer’s stated efficiencies per Section 8.3.1.5.
d. ITE Distribution Segment Efficiency: The longest path with the Electrical Component Efficiency: Indicate whether the rated or unrated equipment values have been used. For rated equipment, the values used in the calculations shall be the manufacturer’s numbers as derived from standardized testing per Section 8.3.1.9(a). For unrated equipment, provide verification that the efficiency values or losses have been verified per Section 8.3.1.9(b).

Campus Applicable
No
Internationally Applicable:
Yes
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Intent

To achieve increasing levels of energy performance beyond the prerequisite standard to reduce environmental and economic harms associated with excessive energy use.

Requirements

Establish an energy performance target no later than the schematic design phase. The target must be established using one of the following metrics:

  • kBtu per square foot-year (kWh per square meter-year) of site energy use
  • kBtu per square foot-year (kWh per square meter-year) of source energy use
  • pounds per square foot-year (Kg per square meter-year) of greenhouse gas emissions
  • energy cost per square foot-year (cost per square meter-year)
Analyze efficiency measures during the design process and account for the results in design decision making. Use energy simulation of efficiency opportunities, past energy simulation analyses for similar buildings, or published data (e.g., Advanced Energy Design Guides) from analyses for similar buildings. Analyze efficiency measures, focusing on load reduction and HVAC-related strategies (passive measures are acceptable) appropriate for the facility. Project potential energy savings and holistic project cost implications related to all affected systems. Choose one of the options below.
Option 1. Energy Performance Compliance (1–18 points except Schools and Healthcare, 1–16 points Schools, 1–20 points Healthcare)
Demonstrate a Performance Cost Index (PCI)1 below the Performance Cost Index Target (PCIt) calculated in accordance with Section 4.2.1.1 of ANSI/ASHRAE/IESNA Standard 90.1-2016, Appendix G, Table 4.2.1.1. For mixed use buildings, the required PCI shall be calculated by using an area weighted average of the building types. Calculate the PCI, PCIt, and percentage improvement using metrics of cost and greenhouse gas (GHG) emissions. For each energy source serving the building, the GHG emission factors must be identical for the Baseline and Proposed building models. LEED points are calculated based on the project percent improvement PCI below the PCIt using metrics of cost and GHG emissions. Total points have been divided equally between the metrics of energy cost and greenhouse gas emissions. Points are awarded according to Table 1 and Table 2. For project percent improvement for the cost metric, on-site renewable energy may be subtracted from proposed energy cost prior to calculating proposed building performance per ASHRAE Standard 90.1-2016 Section G 2.4.1.
Table 1. Points for percentage improvement in energy performance – % Cost PCI below PCIt (1-9 points NC and CS, 1-8 points Schools, 1-10 points Healthcare)
New Construction Healthcare, Major Renovation, CS Points BD+C (except Schools, Healthcare) Points Healthcare Points Schools
5% 2% 1 1 1
10% 5% 2 2 2
15% 10% 3 3 3
20% 15% 4 4 4
25% 20% 5 5 5
30% 25% 6 6 6
35% 30% 7 7 7
40% 35% 8 8
45% 40% 9 9 8
50% 45% EP 10 EP
50% EP
*BD+C projects except Data Centers with unregulated energy cost exceeding 50% of the total proposed building energy cost, and BD+C: Data Centers projects with at least 40% gross colocation data center area may use the “Healthcare, Major Renovation, CS” column in lieu of the “New Construction” column. On-site renewable energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance per ASHRAE Standard 90.1-2016 Section G 2.4.1. New off-site renewable energy as defined in EA credit Renewable Energy may be subtracted from proposed greenhouse gas emissions prior to calculating proposed building performance.
Table 2. Points for percentage improvement in energy performance – % Greenhouse Gas Emissions PCI below PCIt (1-9 points NC, 1-8 points Schools, 1-10 points Healthcare)
New Construction Healthcare, Major Renovation, CS, Points BD+C (except Schools, Healthcare) Points Healthcare Points Schools
5% 2% 1 1 1
10% 5% 2 2 2
16% 10% 3 3 3
24% 16% 4 4 4
32% 24% 5 5 5
40% 32% 6 6 6
50% 40% 7 7 7
65% 50% 8 8
80% 65% 9 9 8
100% 80% EP 10 EP
100% EP
*BD+C projects except Data Centers with unregulated energy cost exceeding 50% of the total proposed building energy cost, and BD+C: Data Centers projects with at least 40% gross colocation data center area may use the “Healthcare, Major Renovation, CS” column in lieu of the “New Construction” column.
DATA CENTERS ONLY
In addition to the requirements above, analyze efficiency measures focused on IT load reduction and HVAC-related strategies. Collocated data centers may use the CS percentage improvement thresholds in lieu of NC thresholds to earn points in Table 1 and Table 2. OR
Option 2. Prescriptive Compliance: ASHRAE Advanced Energy Design Guide (1–6 points, 1-4 points CS)
To be eligible for Option 2, projects must meet the Scope requirements of the applicable AEDGs (or combination of AEDGs for mixed use), and projects must use the ASHRAE 90.1-2016 Prescriptive compliance path in EA Prerequisite Minimum Energy Performance. Implement and document compliance with the applicable recommendations and standards in Chapter 4, Design Strategies and Recommendations by Climate Zone, for the appropriate ASHRAE 50% Advanced Energy Design Guide and climate zone. ASHRAE 50% Advanced Energy Design Guide for Small to Medium Office Buildings
  • Building envelope: roofs, walls, floors, slabs, doors, continuous air barriers, and vertical fenestration (1 point, 2 points CS)
  • Interior and exterior lighting, including daylighting and interior finishes (1 point). CS: Minimum 20% of building area must have a complete lighting design.
  • Plug loads, including equipment and controls (2 points, 0 points CS)
  • HVAC Systems and Controls (2 points, 1 point CS). CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume.
ASHRAE 50% Advanced Energy Design Guide for Medium to Large Box Retail Buildings
  • Building envelope: roofs, walls, floors, slabs, doors, vestibules and fenestration – all orientations (1 point, 2 points CS)
  • Interior and exterior lighting, excluding lighting power density for sales floor (1 point). CS: Minimum 20% of building area must have a complete lighting design
  • Additional interior lighting for sales floor (1 point, 0 points CS)
  • Plug loads, including equipment choices and controls (1 point, 0 points CS)
  • HVAC efficiency and control requirements (2 points, 1 point CS). CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume)
ASHRAE 50% Advanced Energy Design Guide for K–12 School Buildings (Not applicable for CS)
  • Building envelope: roofs, walls, floors, slabs, doors and vertical fenestration (1 point)
  • Interior and exterior lighting, including daylighting and interior finishes (1 point)
  • Plug loads, including equipment choices, controls, and kitchen equipment (2 points)
  • HVAC efficiency and control requirements (2 points)
ASHRAE 50% Advanced Energy Design Guide for Large Hospitals
  • Building envelope: roofs, walls, floors, slabs, doors, vestibules, continuous air barriers, and vertical fenestration (1 point, 2 points CS)
  • Interior and exterior lighting, including daylighting (form or nonform driven) and interior finishes (1 point). CS: Minimum 20% of building area must have a complete lighting design
  • Plug loads, including equipment choices, controls, and kitchen equipment (1 point, 0 points CS)
  • HVAC and Service Water Heating Systems and Equipment (2 points) (1 point CS. CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume)
ASHRAE 50% Advanced Energy Design Guide for Grocery Stores
  • Building envelope: roofs, walls, floors, slabs, doors, vestibules, continuous air barriers, and vertical fenestration (1 point) (2 points – CS)
  • Interior and exterior lighting, including sales floor (1 points)
  • Refrigeration, Plug, and Process loads, including equipment choices and controls (2 points)(0 points CS)
  • HVAC efficiency and control requirements (1 point) (1 point CS. CS scope of work must include at least 20% of the building’s projected cooling capacity, heating capacity, and fan volume)
OPTION 3. Systems Optimization (1-4 points)
To be eligible for Option 3, projects must use the ASHRAE 90.1-2016 Prescriptive compliance path in EA Prerequisite Minimum Energy Performance, and must not have more than 2,000 square feet of data center space, laboratory space, or manufacturing space. Demonstrate an improvement beyond ASHRAE/ASHRAE/IESNA Standard 90.1–2016, with errata, for the following systems: Interior and Exterior Lighting; Daylight controls; Building envelope; HVAC and service water heating equipment efficiency; and Equipment and appliances. Each three strategies selected earns 1 point (For Core & Shell lighting and HVAC efficiency measures, the project scope of work must include a complete design for at least 20% of the building area to qualify).
  • Interior and Exterior Lighting:
    • 15% lighting power reduction
    • 30% lighting power reduction
    • 45% lighting power reduction
  • Daylight controls: Install daylight-responsive controls for a given percentage of connected lighting load (lighting in non-regularly occupied space with occupant sensor controls may be excluded from connected lighting load).
    • 35%
    • 70%
  • Building envelope:
    • Climate Zones 1 – 2:
      • Thermal Mass Enclosure: More than 70% of opaque above-grade wall area meets ASHRAE 90.1-2016 definition for “mass wall”; and more than 70% of floor area meets ASHRAE 90.1-2016 definition for “mass floor”
      • 25% Envelope UA reduction
      • 50% SHGC reduction (including window shade factors)
    • Climate Zones 3 – 8:
  • HVAC and Service Water Heating Equipment Efficiency:
    • Reduction in total fan power allowance of:
      • 15%
      • 30%
      • 45%
    • Improvement in efficiency for at least 75% of the combined cooling, heating, and service water heating capacity
      • 10%
      • 20%
      • 30%
      Electric resistance heating except heat pump auxiliary heat must be included in total capacity.
  • Equipment and Appliances: Install a percentage (by rated power) of eligible equipment and appliances meeting the following requirements:
    • ENERGY STAR equipment including appliances, office equipment, electronics, and commercial food service equipment (lighting and building envelope products are excluded from this credit). (Electronic Product Environmental Assessment Tool (EPEAT) equipment may be used in lieu of Energy Star equipment where applicable).
    • Prescriptive commercial kitchen and refrigeration equipment requirements listed in Appendix 3, Table 1.
    The project scope of work must include at least 0.25 Watts per square foot of eligible equipment to apply this strategy.
Percent of Eligible Equipment Installed by Rated Power:
  • 20%
  • 40%
  • 60%
  • 80%
  • 100%
OR
OPTION 4. DATA CENTERS ONLY– SYSTEM OPTIMIZATION (1 TO 3 POINTS)
Calculate an Overall Systems Design Value as the sum of the maximum design Mechanical Load Component (MLC) and maximum design Electrical Load Component (ELC) in accordance with ASHRAE 90.4-2016 Section 6.2, Section 8.2, and Section 11. Document that the Overall Systems Design value is less than the Maximum Overall Systems Value by:
  • 10% (1 point)
  • 20% (2 points)
  • 30% (3 points)
*If the electrical system design is incomplete, the design values shall be assumed to match the values in Table 8.2.1.1 and 8.2.1.2. Collocated data centers: document that the Overall Systems Design value is less than the Maximum Overall Systems Value by:
  • 6% (1 point)
  • 12% (2 points)
  • 18% (3 points)

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7group / Energy Opportunities
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