05.08.2010

TEAM GEOMELT

The Team

Jacob Speelman

(ME)

Caleb Rottman (EE)

RICO Ledy (ME)

Eric Geerlings

(CE)

OutlineProject OverviewMajor Design DecisionsDesign

SnowmeltGeothermalSite DevelopmentModel

ConclusionsQuestions

Project OverviewProblems with the Burton St. Entrance to

CalvinWhy not use Geothermal energy?

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions

Overview - GoalsPrimary Goal: Design a geothermal

snowmelt system at Calvin’s Burton Street Entrance

Secondary Goal: Design a small scale model

Overview Decisions SnowmeltGeotherma

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Conclusions

Questions

Overview - Design NormsStewardship

Save on energy and reduce fossil fuel useCaring

Increase safety for pedestrians and vehiclesTransparency

Honest recommendation

Overview Decisions SnowmeltGeotherma

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Conclusions

Questions

Major Design DecisionsSnowmelt

What surfaces to meltIs a heat pump required?

GeothermalHorizontal vs. Vertical

Site DesignPumphouse locationPiping and manifold layout

ModelComponent selection

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions

Snowmelt Design - Overview4,000 ft2 to melt at 150 BTU/hr- ft2 60 tons – About 20 times that of a

houseManifolds are used to distribute heat

to the snowmelt area

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions

Snowmelt Design – Pipe Layout

• 1” PEX pipe

•500’ length loops

•9” on center pipe spacing

•3” from concrete surface

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions

Condenser

Evaporator

From Geothermal Loops

To Snowmelt Loops

Q

Q

Compressor

Snowmelt Design – Heat PumpEntering temperature of

105 °FExiting temperature of 90

°F

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions

Geothermal DesignFirst Major Step in the Geothermal Design:

Pipe layout: Horizontal or VerticalAdvantage/Disadvantage Analysis

Design Choice: Vertical Loop

Cooling ground over time?

Overview Decisions SnowmeltGeotherma

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Conclusions

Questions

Geothermal DesignCalculated the total bore length required: 9375

ftLimit Bore Depth to 390 ftPipe diameter – 1 ¼”

http://img.directindustry.com/images_di/photo-g/well-drilling-rig-354735.jpg

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

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Geothermal Design24 Well Locations

Adequate spacing2” HDPE pipe to pump

house3 rectangular manifoldsDesign avoids tree removal!Pumphouse hidden from

view

Overview Decisions SnowmeltGeotherma

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Conclusions

Questions

Site Design - Pumphouse

Overview Decisions SnowmeltGeotherma

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Conclusions

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Plan View

Isometric View

Model DesignConcrete with

installed piping and moisture sensor

InsulationSand Sub-baseSoil with installed

vertical geothermal loop

Overview Decisions SnowmeltGeotherma

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Questions

Model Control System

Overview Decisions SnowmeltGeotherma

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Conclusions - Cost Analysis

Payback Period: 55 yearsOur recommendation: Don’t do it!

Geothermal System

Natural Gas System

Initial Cost $420,000 $180,000

Operating Cost

$6,600 $10,900

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions

ConclusionsWhy is this not economically feasible?We had three false assumptions:

Snow can be melted with ground temperature water

The entrance being isolated is a problem for traditional snowmelt systems

The ground can be an unending heat source

Overview Decisions SnowmeltGeotherma

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Conclusions

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AcknowledgementsTrent DeBoer, GMB EngineeringSteve Schultz, GMB EngineeringScott Post, Prein&NewhofCharles Huizinga, Calvin College Physical PlantMarc Huizinga, Calvin College Physical PlantProfessor Nielsen, Team AdvisorRen Tubergen, Gumbo Product Development,

Inc.Gary Slykhouse, City of GR Engineering Dept.Bob Bruggink, Moore & Bruggink, Inc.

Overview Decisions SnowmeltGeotherma

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Conclusions

Questions

Questions

Overview Decisions SnowmeltGeotherma

lSite Design Model

Conclusions

Questions