Presented by Pete Jefferson
M.E. Group, Inc.

Geothermal Basics
Applications
Advantages of Geothermal
Process for Implementing Geothermal
Palmer Ridge High School Case Study
Brent’s Place Case Study

Also called “Geoexchange” or ground
Geoexchange ground-
source.
Works for both heating and cooling
g g
purposes.
Takes advantage of relatively stable
ground temperatures (50-55 F).
Works in any location.
Ground ater temperature
Gro nd water temperat re maintained
between 25 F to 95 F.
Moves “heat”, doesn’t move “cool”.
heat doesn t cool

Summer Operation
•Moves heat from room
into refrigerant line.
•Refrigerant line moves
heat to ground loop
water.
•Ground loop water
moves heat to earth
earth.
•Ground loop water
returns to compressor
cooler
•Similar t normal A/C
Si il to l
process conceptually.

Winter Operation
•Heat moves from earth
into ground water loop
•Water loop moves heat
to refrigerant line
•Refrigerant line moves
heat to room
•Ground water returns to
Ground
earth cooler

Horizontal Loop Vertical Loop

Typical schematic:

Other sources for geothermal:
• Ponds
• Rivers
• Aquifers
• Volcanic areas
• Open loop

Building heating and cooling
Hot water heating
Process cooling
Snowmelt systems

Geothermal can be used on any project
type
Historically,
Historically these projects have used
geothermal systems most often:
• Schools
• Government
• Offices
• Residences

Energy Efficiency
• SEER ratings of up to 27 versus the average 13
SEER cooling unit
• Can be 5 times more efficient in heating mode
• Takes advantage of simultaneous heating and
cooling, rather than wasting energy
• Qualifies for rebates in many locations
• Payback of 3-10 years without rebates
f 3 10

Less maintenance
Space savings
This manifold system
serves a 220-ton, 75,000
square foot facility. There
are no boilers chillers or
boilers, chillers,
cooling tower.

Technology
HVAC System
Daylighting
Building Envelope

1.
1 Obtain geothermal conductivity test ($6-8
($6 8
K, well is reusable)
2.
2 Determine type of well field (horizontal vs
vs.
vertical)
3.
3 Payback analysis
4. Ensure adequate ceiling space (3-4 feet if
horizontal heat pumps)
5. Locate units for accessibility , noise
control,
control and temperature zoning
zoning.

217,000 square feet
217 000
Why did we go with geothermal?
Soil profile
200 wells, 400 feet deep, 20 feet on center
serves 440 tons of load
Rebates/grants
• $190 000 from Intermountain Electric / MVEA
$190,000
Largest geothermal heat pump project in
state of Colorado

Why did we go with geothermal?
Soil issues
54 wells 300 feet deep 20 feet on center
wells, deep,
serves 50 tons of load
Rebates/grants
• $25K from Xcel Energy
• Grants from Kresge Foundation

Geothermal Heat Pump Consortium
• http://www.geoexchange.org
Department of Energy
• http://www1.eere.energy.gov/geothermal/