e Study:
Iowa Association of Municipal Utilities (IAMU)
Photos: Assassi Productions - 2001
Office and
Training
Complex IOWA ENERGY CENTER
Energy Resource Station
ERS
IAMU: A Commitment to
Sustainable Building Practices
Owner Perspective Reduce Building Energy
Consumption Improve Ecology of Site Appropriate Selection of
Building Materials Provide Healthy and
Productive Human
Environment Limited Budget
Design Team Perspective Commitment to Energy Efficiency Sustainable Design Approach IOWA ENERGY CENTER
Energy Resource Station
ERS
H
2 X H
2 X H
H
North
Building Plan Concepts
Orient Building on primary
East/West Axis
Provide Daylight from North
and South Orientations
Minimize East/West Orientation
and Glazing
High South Wall captures Daylight
Lower North Wall protects against
Prevailing Winds
Proportion Interior Spaces no deeper
than 2 times Window Head Height
Use Glazing judiciously to accomplish
View, Daylight and Ventilation
Window to Window to
Wall area
Floor area
North
13%
2.4%
South
25%
7.5%
East
25%
2.9%
West
6%
0.7%
Total
19%
13.6% IOWA ENERGY CENTER
Energy Resource Station
ERS
High Performance Building Envelope
Six Inch Exterior Wall Thickness
Sprayed Foam (Icynene) Insulation
Low-E triple pane Windows
Vestibule Entrances
Site Orientation IOWA ENERGY CENTER
Energy Resource Station
ERS
20 degree
min. winter
profile angle
Daylighting Concepts
Visual Connection to Outdoor Environment
Enhance Human Performance
Reduce Need for Electric Lights
Reduce Need for Air Conditioning
Open Office area - 32 deep
Private Office 16 IOWA ENERGY CENTER
Energy Resource Station
ERS
Window System
Low E, Triple Pane, Wood
Frame, Operable Windows.
Specifications vary by orientation
Electric Lighting
System
8 Two-Lamp Indirect Industrial
Fixture mounted Upside Down
T8 lamps w/ Electronic Dimming
Ballast
Illumination Level @ 30 to 35 fc
Connected Lighting Power
Density at 1.15 watts per SF
White Painted Metal Deck
Ceiling with 85% reflectance
Daylighting Design
Open Office area - 32 deep
Private Office 16
1
2
3
4
5
6
10
9
10
8
7
11
20 degree
min. winter
profile angle
SC
U-value
VT
North/South
0.44
0.35
0.67
East/West
0.35
0.25
0.60
North Daylight Zone
One photosensor for every
three north facing offices
No blinds on north windows
Wall box occupancy sensor
for each office
Transom/vision glass to
provide bi-directional source
and transparency
Center Daylight Zone
One photosensor controlling
all lights in center zone
Seasonal banner to control
low angle direct sun during
winter months only
Supply duct doubles as light
shelf to control direct sun on
south open office areas
1
9
2
8
3
4
5
South Daylight Zone
One photosensor controlling all
lights in south zone
Daylight transom window - 15
head height w/ no blinds
5 roof overhang and lower
sunscreen effectively blocks
direct sun during cooling season
Horizontal blinds on south view
window - light color - vertical
blinds on east windows
11
10
6
7
RDG Bussard Dikis & The Weidt Group Energy Design copyright 2001 IOWA ENERGY CENTER
Energy Resource Station
ERS
Mechanical System Concepts
North
Geothermal Heating and
Cooling System Eight Thermal Comfort Zones Energy Efficient Low Maintenance Attractive Life Cycle Cost Doesnt Detract from Building
Aesthetics
Energy Recovery Unit Preheats/Precools Outside Air
with Energy Recovered from
the Rest Room Exhaust Air Two Speed Unit provides
additional Ventilation when the
Auditorium is used
Point of Use Water Heaters IOWA ENERGY CENTER
Energy Resource Station
ERS
North
Geothermal Heating & Cooling Design
Eight Geothermal Heat Pumps Nominal 4 tons Cooling Capacity each Building Total of 32 tons cooling
Geothermal Bore Field Total of 33 vertical bores at 175 feet deep Arranged with 3 circuits of 11 bores each
Loop Pumps Circulate
90 gallons per minute
Loop Temperatures
range from
44°F Winter to
68°F Summer
Simple Programmable
Thermostats Control
Heat Pump Operation IOWA ENERGY CENTER
Energy Resource Station
ERS
Building
Lighting
Panels
HVAC
Equipment
Panels
General
Power
Panels
Maintenance
Building
Panels
Main
Distribution
Panel
M
M
General
Lighting
Task
Lighting
GeoExchange
Heat Pumps
GeoExchange
Loop Pumps
Energy
Recovery Unit
Computer
Office
Equipment
Kitchen
Equipment
Miscellaneous
Power
Lights
Miscellaneous
M
General
Power
M
HVAC System
Power
M
Lighting
Power
M
Maintenance
Building Power
Transformer
M
W
HERE
D
OES
THE
E
NERGY
G
O
?
Main Menu
History
Site
Lighting
M
kW
kWh*
kW
kWh*
kW
kWh*
kW
kWh*
Amps
Amps
Amps
Main Electric
Power
Primary
Electric
Service
* kWh readings represent
current running totals.
Building
Lighting
Panels
HVAC
Equipment
Panels
General
Power
Panels
Maintenance
Building
Panels
Main
Distribution
Panel
M
M
General
Lighting
Task
Lighting
GeoExchange
Heat Pumps
GeoExchange
Loop Pumps
Energy
Recovery Unit
Computer
Office
Equipment
Kitchen
Equipment
Miscellaneous
Power
Lights
Miscellaneous
M
General
Power
M
HVAC System
Power
M
Lighting
Power
M
Maintenance
Building Power
Transformer
M
W
HERE
D
OES
THE
E
NERGY
G
O
?
Main Menu
History
Site
Lighting
M
kW
kWh*
kW
kWh*
kW
kWh*
kW
kWh*
kW
kWh*
kW
kWh*
kW
kWh*
Amps
Amps
Amps
Main Electric
Power
Primary
Electric
Service
* kWh readings represent
current running totals. IOWA ENERGY CENTER
Energy Resource Station
ERS
Actual Building Energy Performance
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
Code Compliant Building
Final Design Estimate
Actual Metered Energy Use
Annual Site Energy KBtu/sf
LIGHTING
17.6
LIGHTING
6.7
LIGHTING
5.7
EQUIPMENT
10.9
EQUIPMENT
10.9
EQUIPMENT
9.1
HVAC
14.6
FAN/PUMP
7.6
FAN/PUMP
9.5
COOLING
9.9
COOLING 4.0
HEATING
19.8
HEATING 3.5
55% Reduction
in Energy Use IOWA ENERGY CENTER
Energy Resource Station
ERS
H
2 X
H
2 X
H
H
Nor
th
Interior Office Spaces
Photo John Burnet IAMU