Building energy modeling consulting example slides and graphical presentations. Energy analysis, daylight modeling, weather visualizations. Studies include:
Building Simulation Process and Tools
Concept Visual Aids
Thermal Comfort Mean Radiant Temperature Mapping
Tech User Plug Load Study
LEED Energy Modeling
Detailed Energy Model :: Laboratory Energy Targeting
Energy Modeling :: Performance EUI Targeting
Detailed Analysis :: Energy Cost and Fuel Switching
Action Oriented Benchmarking :: Making Comparisons
Action Oriented Benchmarking :: Measured Data
Thermal Load Sensitivity for HVAC System Selection
Adaptive Thermal Comfort for Passive Cooling
Thermal Comfort in Active Cooling :: PPD and PMV
Outdoor Thermal Comfort :: UTCI
Daylight Depth and Visual Glare Assessment
Glazing Exterior Visualization and Peak Load Study
Automated Interior Blinds :: Peak Load Study
Local Weather Data Analysis
2. Building Simulation Best of:
1. Building Simulation Process and Tools
2. Concept Visual Aids
3. Thermal Comfort Mean Radiant Temperature Mapping
4. Tech User Plug Load Study
5. LEED Energy Modeling
6. Detailed Energy Model :: Laboratory Energy Targeting
7. Energy Modeling :: Performance EUI Targeting
8. Detailed Analysis :: Energy Cost and Fuel Switching
9. Action Oriented Benchmarking :: Making Comparisons
10. Action Oriented Benchmarking :: Measured Data
11. Thermal Load Sensitivity for HVAC System Selection
12. Adaptive Thermal Comfort for Passive Cooling
13. Thermal Comfort in Active Cooling :: PPD and PMV
14. Outdoor Thermal Comfort :: UTCI
15. Daylight Depth and Visual Glare Assessment
16. Glazing Exterior Visualization and Peak Load Study
17. Automated Interior Blinds :: Peak Load Study
18. Local Weather Data Analysis
4. Thermal Comfort
Outdoor Environment
Indoor Built Environment
Passive Design & Natural Ventilation
Daylighting & Visual Comfort
Building Energy Performance
District Scale Energy Systems
Rhino & Honeybee, Ladybug
IES Virtual Environment
IES VE
Radiance with Rhino
IES VE & OpenStudio
Trnsys
Simulation Tools Actively Used in 2015
8. All Tools & Simulation Services Offered by Integral Group
• Site Weather Mapping
• Envelop / Shading Studies
• Passive Design Modeling
• Annual / LEED Energy Models
• Net Zero Energy / Renewables
• Building / Equipment Retrofit Energy Estimates
• Plug Load Energy Models
• Thermal Comfort Models, PPD and surface
temperatures
• Daylighting Estimates, depth and intensity
• Mech Loads for Sizing
Geometry
Climate
Daylight
Old Energy Tools
New Simulation
Tools
10. Building Performance: Estimating Energy Use
Simulating to Thermal Comfort Standards vs Thermal Air Temperatures
Traditional Energy Modeling
Air Based Thermostat Control
Performance Energy Modeling
Comfort Based Thermostat Control
Plug Loads
14%
Lighting
10%
Heating
25%
Hot Water
1%
Cooling
41%
Pumps
2%
Fans
7%
79
kBtu/sf
11. Building Performance: Estimating Peak Cooling Load Equipment
Simulating to Thermal Comfort Standards vs Thermal Air Temperatures
490 Tons of Cooling
$590,000 First Cost
680 Tons of Cooling
$820,000 First Cost
Assuming $1,200/ton cost for chiller only.
+140% Load
+$330,000
Traditional Energy Modeling
Air Based Thermostat Control
Performance Energy Modeling
Comfort Based Thermostat Control
T Air T Rad
T Air
17. Old Paradigm :: expensive solar panels ::
Design Lead Decisions
Old Paradigm :: Design Development Best
Design Delivery Process for Architecture and Engineering
New Paradigm :: Design Development to Good Enough
high cost of solar
$8/watt
low cost of solar
$3/watt
18. Old Net Zero Energy Paradigm
Maximize the roof,
parking, everywhere
with solar panels
[low $]
Set Energy Use
Budget
Allot budget to plug
loads
Pick most cost effective
strategies: architecture,
lights, HVAC
high performance
Architecture
high performance
HVAC & Lighting
minimize plug
loads
buy solar panels
[high $$$]
New Net Zero Energy Paradigm
20. Building Performance: Thermal and Visual Experience, Architecture and Engineering Decisions
Viracon VE-12M
VLT = 0.70 / SHGC = 0.38
Glazing Specifications, Implications and Shared Goals
All double pane low-e IGU’s with clear glass are not created equal
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
Saint Gobain Cool-Lite Extreme 60/28 II
VLT = 0.59 / SHGC = 0.25
21. Glazing Specifications + Design Day Mean Radiant Temperature
Viracon VE-12M
VLT = 0.70 / SHGC = 0.38
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
Saint Gobain Cool-Lite Extreme 60/28 II
VLT = 0.59 / SHGC = 0.25
22. Glazing Specifications + Design Day Mean Radiant Temperature
Viracon VE-12M
VLT = 0.70 / SHGC = 0.38
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
Saint Gobain Cool-Lite Extreme 60/28 II
VLT = 0.59 / SHGC = 0.25
23. Glazing Specifications + Design Day Mean Radiant Temperature
Viracon VE-12M
VLT = 0.70 / SHGC = 0.38
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
Saint Gobain Cool-Lite Extreme 60/28 II
VLT = 0.59 / SHGC = 0.25
24. Façade Elements: Annual Insolation
West Façade + No External Shading West Façade + 9” West Façade Fins West Façade + 30” West Façade Fins
Understanding the Efficacy of Fixed Shading Options
Total radiation from the sun and sky falling on the building skin
25. Façade Elements + Design Day Mean Radiant Temperature
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
PPG Solarban 70xl + 9” West Façade Fins
VLT = 0.64 / SHGC = 0.28
PPG Solarban 70xl +30” West Façade Fins
VLT = 0.64 / SHGC = 0.28
26. Façade Elements + Design Day Mean Radiant Temperature
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
PPG Solarban 70xl + 9” West Façade Fins
VLT = 0.64 / SHGC = 0.28
PPG Solarban 70xl +30” West Façade Fins
VLT = 0.64 / SHGC = 0.28
27. Façade Elements + Design Day Mean Radiant Temperature
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
PPG Solarban 70xl + 9” West Façade Fins
VLT = 0.64 / SHGC = 0.28
28. Façade Elements + Design Day Mean Radiant Temperature
PPG Solarban 70xl
VLT = 0.64 / SHGC = 0.28
PPG Solarban 70xl + 9” West Façade Fins
VLT = 0.64 / SHGC = 0.28
29. Façade Design: Experiential Impacts
PPG Solarban 70xl PPG Solarban 70xl
+ 9” West Façade Fins
PPG Solarban 70xl
+ 30” West Façade Fins
PPG Solarban 70xl
+ 50% WWR
Viracon VE-12M Saint Gobain CLEX 60/28 II
EUI:
Tonnage:
System Cost:
$/sf
83
680
$816,000
3.6
EUI:
Tonnage:
System Cost:
$/sf
72
580
$696,000
3.1
EUI:
Tonnage:
System Cost:
$/sf
65
530
$636,000
2.8
EUI:
Tonnage:
System Cost:
$/sf
65
570
$684,000
3.0
EUI:
Tonnage:
System Cost:
$/sf
55
570
684,000
3.0
EUI:
Tonnage:
System Cost:
$/sf
54
430
$516,000
2.3
Thermal Impacts, Visual Impacts, Energy Impacts, Aesthetic Impacts, Cost Impacts…
31. 50% Design Intent
(assumed)
Plug Load Study
Finding
(data driven)
With Thin- Clients and
Remote -computers
With Thin-Clients and
virtualized
computers
540 W@ desk 330 W@ desk 110 W@ desk
75 W remote
110 W@ desk
25 W remote
MEP First Costs
$78.0 M $77.1 M $76.0 M $75.8 M
Annual Costs
$ 3.01 M $2.81 M $2.42 M $1.97 M
NPV 10 yrs
$96 M $94 M $91 M $88 M
9/8/2022
*assuming a 10% discount rate
1 per user
Multi-user
server
Selecting the Right Computer Plug Loads
32. 50% Design Intent
(assumed)
Plug Load Study
Finding
(data driven)
With Thin- Clients and
Remote -computers
With Thin-Clients and
virtualized
computers
540 W@ desk 330 W@ desk 110 W@ desk
75 W remote
110 W@ desk
25 W remote
9/8/2022
*assuming a 10% discount rate
1 per user
10 Year
NPV
$96 M $94 M
$91 M
$88 M
$78 M
$88 M
$98 M
MEP First Costs
Multi-user
server
Selecting the Right Computer Plug Loads
33. 9/8/2022
50% Design Intent
(assumed)
Plug Load Study
Finding
(data driven)
With Thin- Clients and
Remote -computers
With Thin-Clients and
virtualized
computers
540 W@ desk 330 W@ desk 110 W@ desk
75 W remote
110 W@ desk
25 W remote
Workfloor cfm/sf 0.41 cfm/sf 0.36 cfm/sf 0.33 cfm/sf 0.33 cfm/sf
Plant Sizing tons 1,950 tons 1,772 tons 1,651 tons 1,562 tons
Energy Use Intensity 90 kBtu/sf 85 kBtu/sf 74 kBtu/sf 61 kBtu/sf
Selecting the Right Computer Plug Loads
35. 0
50
100
150
200
250
Baseline -
ASHRAE 90.1-
2007
Proposed with
Water Cooled
Chiller
EUI,
kWh/m2-yr
Energy Use Intensity, kWh/m2-yr
DHW
Heating
Pumps
Fans
Refrigeration
Heat Rejection
Cooling
Lighting
Plug/Equip
Misc
LEED Summary
While new construction buildings often out perform their
existing building peers, most new construction projects
fail to achieve their anticipated energy use due to a
number of reasons from design to constructability. By
selecting an energy performance target of exact energy
use, the goal is to have this building perform as intended
and bring transparency to the process.
This project is aiming to achieve a low Energy Use
Intensity (EUI) target. This metric is a measure of the
building’s annual energy consumption relative to the
building’s gross square footage. In addition to setting an
EUI target, LEED requires that an ASHRAE Baseline be
used as a means of comparison. The ASHRAE baseline
represents a building which met the minimum
requirements of ASHRAE.
36. $31
$22
0 5 10 15 20 25 30 35
Baseline -
ASHRAE 90.1-
2007
Proposed with
Water Cooled
Chiller
Annual Energy Cost, $/m2
Annual Energy Cost per Year ($/m2)
Uncertainity range
LEED Summary
The building design is targeting LEED version 3
Platinum level performance and is currently showing
energy cost savings of 30-36% for 10-13 out of 19
LEED EA c1 points. Additional points may be
obtainable with on-site solar power generation to
increase EA c1 points as well as capture EA c2
renewable energy points.
Utility cost estimates are based on the provided
electrical and gas rates:
$0.167/kWh for Electricity
$0.86/Liter of Fuel ($2.53/therm)
% Energy
Cost
Savings
LEED EA
c1 Points
% Energy
Cost
Savings
LEED EA
c1 Points
12% 1 30% 10
14% 2 32% 11
16% 3 34% 12
18% 4 36% 13
20% 5 38% 14
22% 6 40% 15
24% 7 42% 16
26% 8 44% 17
28% 9 46% 18
48% 19
38. 213
159
140
99
0
50
100
150
200
250
Basic Practice Good Best Target
Annual
Energy
[kbtu/sf]
Defining Energy Target and Baselines
Setting realistic energy goals requires understanding
building location, geometry and – most importantly –
programming. The energy demands of higher
education laboratory spaces varies by discipline and
use but are much higher than those of classroom or
offices.
The ‘basic practice’ benchmark has been built using
existing building energy use databases. It take into
account the relative building area of the different
programming types, and their relative energy densities.
The ‘good’ and ‘best’ benchmarks were developed in
early SD by the design team based on anticipated
design practices.
39. Geometry
• Matched model to updated geometry
Internal Loads
• Reduced Lighting energy based on current design
• Added Physics Process Loop based on VZ feedback
• Reduced Plug Load energy based on Plug Load Study results
HVAC
• Outdoor Air Pre-heat with Medium Temperature CHW Loop
• DHW Preheat from CW Loop
• Added Condenser Water Loop for Walk-in Freezers
• Preliminary assumed efficiencies
Next Steps
• Incorporate schedules
• Review Lab Process Loop + CW Loop assumptions
• To adjust energy model heating controls
The current EUI is above the target of 99 kbtu/sf, however it expected that design team
feedback will result in a reduction of energy use. The project goal is still an EUI of 99 kbtu/sf.
Energy Modeling :: Major Model Updates
40. 0
2
4
6
8
10
12
14
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Energy
use
Intensity
[kbtu/sf]
Exterior Ltg
Lighting
Fans
Pumps
Cooling
Physics Process Loop
Hot Water
Heating
Process Steam
Elevators
Cold Rooms Compressor
Water Cooled Eqp. Plug Load
Plug Loads
0
100
200
300
400
500
600
tons
AHU Cooling
Zone Cooling
Process + CW Load
Jan Oct
Sep
Aug
July
Jun
May
Apr
Mar
Feb Dec
Nov
Monthly Solar Gain Comparison
41. MT CHW Loop Outdoor Air Preheat
CW Loop Heat Recovery
Modeled HVAC Systems
42. Model Update Summary
Updates since SD
Heat Recovery system modeled in
detail
Updated Occupancy and Airflow
schedules
a
Impacts to energy results
Results in an EUI savings of 1.5
kbtu/sf-yr
Reason for lower savings from initial
modeling is due to a
lower baseline heating demand
Plug Loads inc Labs, 47
Plug Loads (inc. some lab
plugs), 28
Water Cooled Eqp. Plug
Load, 11
Cold Rooms Compressor, 2
Elevators, 0.1
Elevators, 0.1
Process Steam, 3
Process Steam, 2
Heating
31
Heating
17
Hot Water, 6
Hot Water, 2 Physics Process Loop, 3
CW Loop, 2
Cooling, 8
Cooling, 7
Pumps, 3
Pumps, 1
Fans, 3
Fans, 9
Lighting
9
Lighting
8
Exterior Ltg, 1
Exterior Ltg, 1
0
20
40
60
80
100
120
SD DD Snapshot
Annual
Energy
[kbtu/sf]
213
110
93
0
50
100
150
200
250
Amherst Science
Center Benchmark
SD Model DD Snapshot
Annual
Energy
[kbtu/sf]
High Risk
104
Low Risk 80
43. 0
10
20
30
40
50
60
70
80
90
100
Annual
Energy
[kbtu/sf]
Exterior Ltg
Lighting
Fans
Pumps
Cooling
CW Loop
Physics Process Loop
Hot Water
Heating
Process Steam
Elevators
Cold Rooms Compressor
Water Cooled Eqp. Plug Load
Plug Loads (inc. some lab plugs)
Model Update Summary
1. Updated Lab Schedules
Occupancy schedules
Lab Airflow (in ACH) Schedules
2. Low-Flow Fume Hood Analysis
Results in an EUI savings of 1.5 kbtu/sf-yr
Reason for lower savings from initial modeling is due
to a lower baseline heating demand
3. Current EUI is below the 99 target
Major changes include:
Reduced Heating due to better modeling of Heat Recovery
Higher Fan Energy due to updated schedules
4. Setpoint Analysis
Using the setpoints in the current design will result in
a 1.7 EUI savings compared to typical setpoints
Note: Pumping energy appears low and is being
investigated
0.0
0.5
1.0
1 8 15 22
Academic Weekdays
1 8 15 22
Academic Weekends
1 8 15 22
Research Weekdays
1 8 15 22
Research Weekends
0
2
4
6
1 8 15 22
Academic Weekdays
1 8 15 22
Academic Weekends
1 8 15 22
Research Weekdays
1 8 15 22
Research Weekends
Occupancy
ACH Rates
44. Updated Lab Schedules
Occupancy schedules were provided
Lab Airflow (in ACH)
The updated occupancy and airflow schedules
for the Chemistry labs and the Biology / Physics
labs (they use the same schedules) are shown at
right.
Non-lab space schedules have also been
updated.
0.0
0.5
1.0
1 8 15 22
Academic Weekdays
1 8 15 22
Academic Weekends
1 8 15 22
Research Weekdays
1 8 15 22
Research Weekends
0
2
4
6
1 8 15 22
Academic Weekdays
1 8 15 22
Academic Weekends
1 8 15 22
Research Weekdays
1 8 15 22
Research Weekends
Occupancy
ACH Rates
Chemistry
0.0
0.5
1.0
1 8 15 22
Academic Weekdays
1 8 15 22
Academic Weekends
1 8 15 22
Research Weekdays
1 8 15 22
Research Weekends
0
1
2
3
4
1 8 15 22
Academic Weekdays
1 8 15 22
Academic Weekends
1 8 15 22
Research Weekdays
1 8 15 22
Research Weekends
Occupancy
ACH Rates
Biology + Physics
45. Low Flow Fume Hood Analysis
The model lab air flow has a 2 ACH minimum during
unoccupied hours, and 4 ACH minimum during occupied
hours.
During the Research Weekdays (M-F during January and
July-Sept) the ACH increases above 4 ACH for a few hours
due to occupancy.
The chemistry lab airflow schedule has a 64,000 CFM
peak across all chemistry labs. This works out to an
average of 5.4 ACH, however this occurs for a limited # of
hours. There are approximately 500 hours per year above
the 4 ACH minimum air flow during occupied hours.
A second schedule has been generated to model the
impact of low flow fume hoods. This reduces the airflow
peak to 4 ACH during occupied hours. This results in a
total airflow of 48,000 CFM and a peak airflow reduction of
16,000 CFM
0
2
4
6
1 8 15 22
ACH
Research Weekdays
0
2
4
6
1 8 15 22
ACH
Research Weekdays – Low Flow
0
2
4
6
1 8 15 22
ACH
Academic Schedule + Research Schedule Weekends
46. 0
10
20
30
40
50
60
70
80
90
100
Annual
Energy
[kbtu/sf]
Exterior Ltg
Lighting
Fans
Pumps
Cooling
CW Loop
Physics Process Loop
Hot Water
Heating
Process Steam
Elevators
Cold Rooms Compressor
Water Cooled Eqp. Plug Load
Plug Loads (inc. some lab plugs)
Current EUI
Heat Recovery system is providing more
heating than previous model, resulting in an
overall decrease in heating EUI (ie heating
provided by steam system)
Fan Use is higher due to unoccupied lab
minimum of 2 ACH. Previously lab minimums
tracked lower than this to follow occupancy.
Pumping energy appears low and needs to be
investigated further. It is likely that it will
increase, but the project will still be on target to
hit energy goals.
Current EUI is 94 kbtu/sf, below the EUI
target by 5%
47. Heating, 17 Heating, 16
Cooling, 7
Cooling, 6
0
10
20
30
40
50
60
70
80
90
100
DD Snapshot Energy Saving Thermostat Setpoints
Annual
Energy
[kbtu/sf]
Exterior Ltg
Lighting
Fans
Pumps
Cooling
CW Loop
Physics Process Loop
Hot Water
Heating
Process Steam
Elevators
Cold Rooms Compressor
Water Cooled Eqp. Plug Load
Plug Loads (inc. some lab plugs)
Setpoint Analysis
The current DD Snapshot model
assumes conservative thermostat
setpoints.
The design has setpoints designed
to save energy.
The benefit of implementing these
setpoints results in a savings of 1.7
kbtu/sf-yr.
54. Lab spaces can use 4-5x as much energy as a normal office. Depending on
programming the mix of spaces leads to more or less energy use.
0
100
200
300
400
500
100%
Lab
80%
Lab /
20%
Office
60%
Lab /
40%
Office
40%
Lab /
60%
Office
20%
Lab /
60%
Office
100%
Office
kBtu/sf-yr
Baseline EUI
Gas
Electric
Energy - Baseline – Percent Laboratory Use vs Office
55. 0
50
100
150
200
250
300
LBNL Campus
Average -
Measured
Labs 21 -
Measured
kBtu/sf-yr
EUI
Total
Gas
Electric
• Lab buildings have the
potential to use a significant
amount of energy
• Campus Average taken
from Long Range
Development Plan
• Labs 21 data represents 4
measured labs in
California’s climate zone
with at least 50% lab space
Energy Use Intensity (kBtu/sf-yr)
Energy - Baseline
56. Cooling,
11%
Heating,
36%
Fan/Pump,
16%
Lighting, 8%
Plug/Equip,
29%
Typical Lab Space Energy Use
• Typical of lab dominated buildings
(80% Lab / 20% Office)
• Ventilation and plug loads
dominate energy use
• Heating is a mixture of reheat and
outside air conditioning for
ventilation
Energy Breakdown of Typical Laboratory
57. 0
50
100
150
200
250
300
LBNL Campus
Average -
Measured
ASHRAE 90.1-
2010 Baseline:
60% Lab / 40%
Office
30% Better
than ASHRAE
Target
Net Zero Lab:
40% Lab / 60%
Office
kBtu/sf-yr
Energy Use Intensity Comparison
Gas
Electric
Fan/Pumps
DHW
Cooling
Heating
Lighting
Equip/Plugs
30%
Energy Comparison Summary
58. Option 1 – Module Option 2 – Terrace Option 3 - Link
Building Area 285k sf 315k sf 270k sf
Daylight Perimeter
Area Percentage
48% 31% 44%
Peak Cooling Load
Comparison
29.5 btu/hr-sf 29.6 btu/hr-sf 29.5 btu/hr-sf
Building Massing Options
59. • Topology shades east from
direct sun
• Large southern aspects well
suited for overhangs
• Some western exposure
would need special treatment
to reduce glare and afternoon
direct sun
High Western Exposure
Massing Option 1 - Module
60. • Similar proportion of West to
South aspects as Option 1
• East aspects are nestled in the
topology and completely
shaded
Late afternoon sun will cause glare
and high solar loads on western
aspects
Massing Option 2 - Terrace
61. • Large western exposure treated
with vertical sun shades
• Largest footprint area of the 3
options
Vertical shades structure
designed to block afternoon
sun
Massing Option 3
82. 0
200
400
600
800
1,000
1,200
1,400
1,600
May-09 Sep-09 Jan-10 May-10 Sep-10 Jan-11 May-11 Sep-11 Jan-12
Therms
Heating Measured vs Predicted
Mills GSB, Natural Gas
Actual Modeled
250%
More
Heating
Required
Building Benchmarking
DOE2 energy model as referenced. No weather correction factored in yet the trend still stands in order of magnitude.
83. 390%
More
Heating
Required
0
200
400
600
800
1000
1200
1400
Oct-08 Feb-09 Jun-09 Oct-09 Feb-10 Jun-10 Oct-10 Feb-11 Jun-11 Oct-11 Feb-12
Therms
Heating Measured vs Predicted
Portola Valley Center, Natural Gas
Actual Modeled
Building Benchmarking
DOE2 energy model as referenced. No weather correction factored in yet the trend still stands in order of magnitude.
84. 180%
More
Heating
Required
0
500
1000
1500
2000
2500
3000
May-09 Sep-09 Jan-10 May-10 Sep-10 Jan-11 May-11 Sep-11 Jan-12 May-12
Therms
Heating Measured vs Predicted
Brower Center, Natural Gas
Actual Modeled
Building Benchmarking
DOE2 energy model as referenced. No weather correction factored in yet the trend still stands in order of magnitude.
85. The Building implemented a low energy passive design to provide a
comfortable indoor climate. The high massive concrete building structure
provides thermal inertia, keeping the building temperatures mild on hot and
cold days. Condensing boilers provide heat through a radiant in-slab loop and
temper fresh air. Modest cooling is provided as a nighttime cool down by a
dedicated cooling tower and heat exchanger. The tower makes moderately cold
water at night and cools down the first floor radiant slab on a night flush cycle.
Outside air is provided through a combination of natural ventilation and two air
handlers at the ground level of the building. Natural ventilation is controlled by
occupants with operable windows and fresh air is filtered and tempered through
the air handlers.
The building is showing great performance at 42% energy savings compared
with Title 24 as measured. Electrical use is lower predicted due to limitations in
the design model to capture the efficient cooling system. Gas use is higher than
anticipated due to mechanical operational controls and hours of use.
During 2011, the air handling units were being turned on earlier than necessary
at 4am, increasing the amount of fresh air tempering daily. The hot water
temperature and supply air temperature were also higher than designed,
contributing to lower operating efficiencies and higher gas use. The building is
estimated to reach the design gas consumption with recommended changes.
Gold Certified LEED v2.2
85%Design Water Savings
42%Measured Energy Savings
0
10
20
30
40
50
60
70
Title 24 Baseline Design Measured 2011
Energy
Use
Intensity,
kBtu/sf-yr
Gas Use kBtu/sf
70% Gas
Savings
Estimated
200%
Gas Use vs
Predicted
0
5,000
10,000
15,000
20,000
25,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
MILLS GSB ELECTRICITY USAGE (KWH) Monthly Data for 2011
ACTUAL USAGE
MODEL ESTIMATE
0
300
600
900
1,200
1,500
1,800
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
MILLS GSB GAS USAGE (THERMS) Monthly Data for 2011
ACTUAL USAGE
MODEL ESTIMATE
0
10
20
30
40
50
60
70
Title 24 Baseline Design Measured 2011
Energy
Use
Intensity,
kBtu/sf-yr
Electrical Use kBtu/sf
22% Electrical
Savings
Estimated
45% Electrical
Savings
Measured
Measured Building Energy Use
86. 0
5
10
15
20
25
30
35
40
45
Modeled Design with Higher
Infiltration
with Lower
Internal Loads
with Higher
Thermostat
setpoints
Measured
Buildings (x2~x3)
Heating
Energy
Use,
kBtu/sf
RadiantSystem Without any Heat Recovery
EngineeringExperience
higher T-stat
Lower internal loads
Infiltration
Modeled Heating
Building Benchmarking :: Predicting Model Discrepancy with Reality
91. Target Load
Envelope improvements include
improved glazing to reduce direct
solar transmission from 0.38
SHGC to 0.25 and overall wall &
glazing insulated performance
x2.
Package 1: Improved Glazing & Envelope Only
92. Target Load
Plug loads per area are reduced
by 50% through high efficiency
computers, laptops, monitors and
other equipment.
Package 2: Reduced Internal Plug Loads Only
93. Target Load
Plug loads per area are reduced
by 50% through high efficiency
computers, laptops, monitors and
other equipment.
Glazing improved in solar
transmission from 0.38 SHGC to
0.25 SHGC.
Envelope insulation values are
kept fixed.
Package 3: Improved Glazing & Reduced Internal Plug Loads
95. Radiant System Selection : Envelope Sensitivity Study
VAV Reheat / Fan Coils
65% Window to Wall
Glazing Ratio
SHGC 0.28 Assembly U 0.4
50% Window to Wall
Glazing Ratio
SHGC 0.28 Assembly U 0.4
35% Window to Wall
Glazing Ratio
SHGC 0.28 Assembly U 0.4
Radiant In-Slab
Above or Below
Radiant Panels
Or Both Ceiling and Floor
330 Peak Tons
Primary Equipment
@$1,200/ton
$2.3/sf
300 Peak Tons
Primary Equipment
@$1,200/ton
$2.1/sf
250 Peak Tons
Primary Equipment
@$1,200/ton
$1.8/sf
Envelope Fenestration HVAC System Limitation Building Peak Cooling Load
96. HVAC Distribution Option A:
Radiant Slab and Underfloor Ventilation
• Radiant slab provides majority of
cooling and heating overhead, 65-
75%
• Underfloor plenum recommended
at 18”
• Underfloor plenum provides
tempered ventilation air
• Low-clearance recirculating fan
coils for high load spaces
• Radiant slab can be
un-insulated on the topside.
• Carpet is acceptable
NOTE: Building Wide WWR @ 40%
Ceiling Fans
Acoustic Clouds
Insulation
Underfloor Ventilation
Radiant Slab
35% Window to Wall Ratio Per Zone
97. HVAC Distribution Option B:
Radiant Slab w/ Overhead Ventilation
• Radiant slab provides majority
of cooling and heating
overhead, 65-75%
• Low velocity, displacement
ventilation type, air distribution
overhead. This type of
ventilation nearly as effective as
Underfloor in removing
pollutants from the occupied
space
• Slab is exposed, or with non-
insulating cover.
• Lowest Cost radiant approach
NOTE: Building Wide WWR @ 40%
Radiant Slab
Overhead Ventilation
35% Window to Wall Ratio Per Zone
98. HVAC Distribution Option A:
Chilled (Radiant) Ceiling Panels
• Higher cooling output (32Btu/h.ft2
vs 25Btu/h.ft2 of in-slab radiant)
and faster response time
• Flexibility to reconfigure radiant
ceiling zone configuration
• High emissivity ideally
complementing low LPD using LED
lights
• Good acoustical performance (the
ceiling panels are perforated with
acoustical mat on top)
50% Window to Wall Ratio Per Zone
NOTE: Building Wide WWR @ 50%
Overhead Ventilation
Radiant Ceiling
99. HVAC Distribution Option B:
Radiant Slab above and below w/ Overhead Ventilation
• Radiant slab provides heating and
cooling overhead.
• Low velocity, displacement type and
floor ventilation, air distribution
overhead. This type of ventilation
nearly as effective as Underfloor in
removing pollutants from the
occupied space.
• Slab is exposed, or with non-
insulating cover.
65% Window to Wall Ratio Per Zone
NOTE: Building Wide WWR @ 50%
Radiant Slab
Overhead Ventilation
Radiant Slab
101. Thermally Active Surfaces in Architecture
Kiel Moe, 2010
Human Thermal Comfort
Predicted
Mean Vote
Air
Temperature
Mean
Radiant
Temperature
Clothing
Insulation
Metabolism
Relative
Humidity
Air Velocity
102. All Air Cooling
Radiant + Air Cooling
High Load
Discomfort
Asymmetry
Thermal Comfort of Air vs Radiant Cooling
103. (a) There is no mechanical cooling system
installed. No heating system is in
operation;
(b) Metabolic rates range from 1.0 to 1.3
met, sitting, light walking.
(a) Occupants are free to adapt their
clothing to indoor and/or outdoor thermal
conditions within a range at least as wide
as 0.5 to 1.0 clo.
This method is applicable only for occupant-controlled naturally
conditioned spaces that meet all of the following criteria:
Adaptive Thermal Comfort in Buildings
104. Based on ASHRAE standard 55.1 2013,
Site weather for San Francisco, CA
Adaptive Thermal Comfort in Buildings
105.
106. Thermal Autonomy is the ability for a space
to provide acceptable thermal comfort
through passive means only. Thermal
comfort is a complex phenomenon
involving thousands of physical interactions
at any given moment. To make matters
worse, thermal comfort is spacio-temporal,
neither a snapshot in time, a summary, nor
an average can tell the whole story.
Seasonal patterns must be understood.
To accomplish this for a whole year, a
sophisticated graphic that is simple enough
was created. - Loisos + Ubbelohde, Alameda, CA
24
0
12
60
311
573
5329
831
664
443
293
142
78
0 2000 4000 6000
<8 F
-8 F
-6 F
-4 F
-2 F
-80%
+/-90%
+80%
+2 F
+4 F
+6 F
+8 F
>8 F
Thermal Autonomy
Percent of Occupied Hours
1620 hrs too Hot
18%
6733 hrs Comfort
77%
407 Hrs too Cold
5%
8760 hrs/yr Occupied
Thermal Autonomy Metric
129. Annual Direct Sun Patterns :: Key Conditions
The west façade receives
substantial direct sun throughout
the year in the afternoon, and will
require automated fabric shades to
maintain visual and thermal
comfort. A light grey tone with an
openness factor between 1 and 2%
would be appropriate.
In the summer months, later
afternoon sun passes through the
north facing glass, and requires a
control strategy.
Vertical mullion fins on the north
could provide sufficient shading for
this condition.
The vertical glass fins provide
substantial shade under a variety of
conditions, highlighting the need for
very dense frit patterns to
effectively shade the sun.
The notch in the south façade
introduces another western
exposure.
On the south façade, low angle
winter sun will pass deep into the
space, also requiring automated
shades to maintain comfort.
130. Shading System Geometry Summary
The combination of vertical and horizontal shade
elements are effective on the south facade.
Interior fabric shades can provide visual comfort
from low angle winter sun. A very dense frit is
necessary on the glass fins to maximize their
usefulness.
The east and west exposures would benefit from
increased fin depth, or from angled fins. These
potential moves would impact the exterior
aesthetic, and require a balance between the
building skin aesthetic and optimal shading.
The north facade would benefit from vertical fin
shade elements to protect from late afternoon sun
in the summer months. These could be integrated
with the mullion cap, and do not need to be as
deep as the south fins.
131. Vertical Fin Frit Density = 60% Coverage
Human Visual Acuity Rendered Perspective
Falsecolor Luminance Map
132. Vertical Fin Frit Density = 80% Coverage
Human Visual Acuity Rendered Perspective
Falsecolor Luminance Map
133. Vertical Fin Frit Density = 90% Coverage
Human Visual Acuity Rendered Perspective
Falsecolor Luminance Map
134. Vertical Fin Frit Density Summary
60% Frit Density 80% Frit Density 90% Frit Density
Daylight Glare Probability (DGP):
1.00
Daylight Glare Probability (DGP):
0.82
Daylight Glare Probability (DGP):
0.67
Daylight Glare Probability (DPG) is a probability metric, describing the likelihood of visual
discomfort due to glare. While looking at the disk of the sun through any medium is likely
to be uncomfortable, these simulations show how an increased frit density can impact
visual comfort. As the vertical fin elements are a critical piece of the shading geometry, a
dense frit pattern is key to their efficacy.
144. • Bogota
0550 Series (5% open)
• This series is composed of finely woven polyester Trevira CS, which is PVC-free and has a smooth
texture. The 0550 Series’ open weave allows natural daylight into an interior while providing a view to
the outside. Bogota is fire retardant and suitable for all types of shading.
• Content: 100% polyester (Trevira CS)
Openness factor: approx. 5%
Stocked: 94 in. (239cm) wide
NFPA 701-2004: pass
550 series Ts Rs As Tv Tu Of
0551 white 0.40 0.54 0.06 0.38 0.16 0.05
0553 med. grey 0.28 0.46 0.26 0.18 0.12 0.05
0557 taupe 0.26 0.43 0.31 0.14 0.10 0.05
0558 black 0.20 0.35 0.45 0.06 0.06 0.04
0570 dark gray 0.21 0.39 0.40 0.10 0.08 0.04
Mecho Shading: Bogata
Medium Gray Color
145. • EcoVeil® Screens
0950 Series (1% open)
• This series is woven in a 1 x 1 basket-weave pattern and is an eco-effective solar sunscreen. As a
Cradle to Cradle CertifiedCM product, it can be reclaimed, recycled, and remain in a perpetual loop of
continuous use. The 0950 Series is available in eight colors and has a 1% density for privacy.
• Content: 100% thermoplastic olefin (TPO)
Openness factor: approx. 1%
Stocked: 100 in. (254cm) wide
NFPA 701-2004: pass
950 series Ts Rs As Tv Tu Of
0951 white 0.14 0.71 0.15 0.12 0.01 0.02
0952 beige 0.10 0.50 0.40 0.07 0.02 0.02
0954 black/brown 0.01 0.05 0.94 0.01 0.01 0.01
0963 grey 0.03 0.32 0.65 0.02 0.01 0.01
0966 eggshell 0.10 0.62 0.28 0.06 Tr 0.01
0967 straw 0.09 0.64 0.27 0.05 Tr 0.01
0969 silver birch 0.07 0.60 0.33 0.05 0.01 0.01
0970 shadow grey 0.01 0.10 0.89 Tr* Tr 0.01
Mecho Shading: EcoVeil
White Color
150. • Psychrometrics
• Fast Time Frame
• Software: Climate Consultant
• Shows pre-packaged design strategies,
feasible or not. High level, limited to graphing
with their colors and limits of strategies.
Visually and statistically limiting.
Site Weather Visualization
151. • Psychrometrics
• Visual Goal & Semi Customizable:
• Software:HANDS DOWN SOFTWARE
• Very visual, bins the hours of
temperatures. Quickly able to do project
specific assessment, hours above /
below a fixed wetbulb, drybulb.
Site Weather Visualization
152. Psychrometrics
Detailed Engineering:
Excel based psychrometrics
Able to bin unique data sets such as night
time hours, summer vs winter, hours
above or below conditions.
0.000
0.002
0.004
0.006
0.008
0.010
0.012
0.014
0.016
0.018
0.020
0.022
0.024
0.026
0.028
0.030
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Humidity
Ratio
(lbs
H2O
/
lbs
dry
air)
Dry Bulb Temperature (F)
Psychrometric Chart
0.000
0.002
0.004
0.006
0.008
0.010
0.012
0.014
0.016
0.018
0.020
0.022
0.024
0.026
0.028
0.030
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Humidity
Ratio
(lbs
H2O
/
lbs
dry
air)
Dry Bulb Temperature (F)
Psychrometric Chart
0.000
0.002
0.004
0.006
0.008
0.010
0.012
0.014
0.016
0.018
0.020
0.022
0.024
0.026
0.028
0.030
-30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Humidity
Ratio
(lbs
H2O
per
lbs
dry
air)
Dry Bulb Temperature (F)
Psychrometric Chart for [location]
Data Source: Custom/User Format --
Data Set: Data Set
Elevation: 20 feet
Air Pressure: 14.68536
psia
Region 1
n/a hrs/yr
Region 2
n/a hrs/yr
Region 3
n/a hrs/yr
Site Weather Visualization
153. • Bioclimatic Chart
• High Level Passive Design
• Software: Excel
• For envelope driven buildings,
assess where the bioclimatic
regions of passively heating and
cooling a building range for the
site.
Feb Jan
Mar
Apr
May
Jun Jul
Aug
Sep
Oct
Nov
Dec
30
40
50
60
70
80
90
100
110
120
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Outisde
Air
Drybulb,
deg
F
Relative Humidity
Comfort Zone
Full Passive Solar Heating
Partial Passive Solar Heating
High Thermal Mass
High Thermal Mass with
Night Ventilation
Natural
Ventilation
Site Weather Visualization
156. • Windrose
• Fast Time Frame
• Software: Climate
Consultant
• Can be more data and
more confusing than it is
worth. Can make in less
than an hour.
Site Weather Visualization
157. • Free Windrose
• Fast Time Frame
• Software: Comfen5
• Can upload a weather file into
Comfen and auto make charts +
download the csv condensed
weather data.
• Comfen best at other weather
visualizations.
Site Weather Visualization
158. • Free Windrose
• Fast Time Frame
• Software: Online / ODS
• http://www.ods-
engineering.com/tools/weather/
• Can upload a weather file into
Comfen and auto make charts +
download a pdf.
Site Weather Visualization
159. • Windrose
• Visual and Detailed
• Software: Rhino
• 3 to 8 hrs
• Can parse wind data by other
parameters, time of day,
temperature outside, and color
rose by any variable. Very
powerful and creative.
Site Weather Visualization
160. • Windrose
• Visual Presentation
• Software: WRPlot/Google
Earth
• Very visual way to overlay
TMY wind data on Google
Earth. Can be combined with
a building geometry.
Site Weather Visualization
161. • Sun Path Diagram
• Fast Time Frame
• Software: Ecotect
• Can quickly map the sun
throughout the year, showing
season red and blue ranges around
the site. Able to snap photos and
assess visually hours and angle of
sun.
Site Weather Visualization
163. • Solar Shading Study
• Software: Ecotect
• Visualize where each façade
sees the sun. Able to quickly
break down what hours and
months need shading.
Site Weather Visualization
164. • Sun Path Diagram
• Detailed Assessment
• Software: Rhino
• Can map the sun for all hours or a
sub set of hours, months and
times.
• Great for more visual and data
specific answers like how many
hours without direct sun.
Site Weather Visualization
165. • Solar Radiation
• Software: Rhino
• Solar radiation or irradiance is a way of
visualizing annually or over a fixed set
of hours how much solar radiation falls
on what surface.
• Very good for showing where shading or
blocking solar energy is needed.
Site Weather Visualization