Garrett Office BuildingsEdmond, Oklahoma

Geothermal Building20,000 Sq. Ft.

VAV Building15,000 Sq. Ft.

Floor 2Conference

Floor 2 Private Office

Floor 2 Open Office Space

Typical Heat Pump

Geothermal BuildingFloor 2 Heat Pump Supply Ducts

141512x16

12x20

8

9 10

11

12

13

16

12x16 10” Typical ofAll BranchDuctsAll Heat Pumps

12x16

12x20

12x20

12x16

12x16

12x20

12x14

12x10

15x20

12x10

Loop Field Overview

Geothermal BuildingLoop Field Site Plan

LoopField

Details

Short headerlocation

2” PE Zone Supply Header - Return Similar3/4” PE borepiping back toheader

Notes:- 40 bores on 20 foot centers each with 3/4” PE pipe- Short header manifold in center of each loop zone of 10 bores- Each bore must have the same overall pipe length for balanced flow

(Coil excess piping in the header trench)

- Loop zone supply and returns done in same fashion- Bores must be grouted when completed

Typical bore

250 ft deep

GeothermalMechanical

Room

GeothermalMechanical

Room

2” PE typical

Heat Pump

Supply

Heat PumpReturn

Expansion

Air

Separator

CWS

Bypass

Pressure Reducer/Relief

Backflow Preventor

3/4”Air Vent

3” Copper

2” PE typical

125 GPM @ 70’

Pumps

Primary/Standby

Ground LoopSupply

Ground Loop

Return

Charging

Floor 1 Heat Pump Piping

Garrett Office BuildingsHighway View

Geothermal BuildingRoof View

VAV BuildingRoof View

VAV BuildingCentral Air Handler

VAV BuildingAir-Cooled Condensing Unit

VAV BuildingBoiler Room

1.50

2.00

2.50

$p

er

Sq

uare

Fo

ot

Garrett Buildings

Annual Energy and HVAC Maintenance Costs 2006-2007

-

0.50

1.00

$p

er

Sq

uare

Fo

ot

VAV System Geothermal

Total Electricity Gas Maintenance

50

60

70

80

90

kB

tup

er

Sq

uare

Fo

ot

Garrett Buildings

Annual Energy Use 2006-2007

-

10

20

30

40

50

kB

tup

er

Sq

uare

Fo

ot

VAV System Geothermal

Total Electricity Gas

40

45

50

Eq

uiv

ale

nt

per

Sq

uare

Fo

ot

Garrett Buildings

Annual CO2 Emissions 2006-2007

20

25

30

35

Lb

s.C

O2

Eq

uiv

ale

nt

per

Sq

uare

Fo

ot

VAV System Geothermal

Electricity Gas

Garrett Buildings

Monthly Energy Use

4

5

6

7

8

9

10

kB

tup

er

Sq

ua

reF

oo

t

0

1

2

3

4

Jul-06 Aug-06 Sep-06 Oct-06 Nov-06 Dec-06 Jan-07 Feb-07 Mar-07 Apr-07 May-07 Jun-07

kB

tup

er

Sq

ua

reF

oo

t

VAV System Geothermal

Garrett Buildings

Monthly Peak Demand

4.0

4.5

5.0

5.5

6.0

Watt

sp

er

Sq

uare

Fo

ot

2.0

2.5

3.0

3.5

Jul-06 Aug-06 Sep-06 Oct-06 Nov-06 Dec-06 Jan-07 Feb-07 Mar-07 Apr-07 May-07 Jun-07

Watt

sp

er

Sq

uare

Fo

ot

VAV System Geothermal

Garrett Buildings

Monthly Electricity Supply Load Factor

40

50

60

70

Lo

ad

Facto

r

20

30

Jul-06 Aug-06 Sep-06 Oct-06 Nov-06 Dec-06 Jan-07 Feb-07 Mar-07 Apr-07 May-07 Jun-07

VAV System Geothermal

Garrett Office BuildingsInstallation Costs

• Geothermal System circa 1998– Complete exterior loop, mechanical room,

interior PE piping, flushing and unit startup,heat pumps, duct work, exhausts, MUAsystem, timeclock-based controlssystem, timeclock-based controls

– $128,700 ($2,574 per ton)

• VAV System circa 1987– air-cooled condenser, VAV air handler,

boiler, VAV boxes with reheat coils,economizer, electronic controls

– $100,000 ($2000 per ton)

– costs per building owner do not includestructural or architectural