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Curtis J. Klaassen, P.E.Iowa Energy Center
Energy Resource Station
IOWA HEAT PUMP ASSOCIATION
Geo 101 – v09
Introduction to GeothermalHeat Pump Systems
2009 Conference
Introduction
Geothermal Heat Pump System Types
Geothermal System Features● Pros and Cons● Applications
Geothermal System Economics
A Residential Perspective
Questions at Any Time……
Geothermal Heat Pump Technology
2
The Iowa Energy Center
Advancing Iowa’s Energy Efficiency andRenewable Energy Use Through
Research, Demonstration and Education
Provide balanced energy informationServe as a resource for energy issues, research & technologySupport community, business and individual efforts with energy efficiency & renewable energyAdminister Alternative Energy Revolving Loan Program
Projects:Energy Resource Station, Ankeny
Biomass Energy Conversion Facility, NevadaResearch, Education & Demonstration Grants
Alternate Energy Revolving Loan Program
www.energy.iastate.edu
Building Energy in PerspectiveBuildings Use 40% of the Nation’s Primary Energy
22%
18%
32%
28%
Residential
Commercial
Industry
Transportation
Total Residential & Commercial = 40%
Buildings Use 72% of the Nation’s ElectricityResponsible for 39% of the Nation’s Greenhouse
Gas Emissions2007 Building Energy Databook
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Energy Efficiency – Building BlocksStep 1 – Reduce Energy Load● Site Orientation and Building Arrangement ● Efficient and Effective Building Envelope
Step 2 – Improve Efficiency of Systems and Equipment● HVAC Systems – Geothermal Systems● Lighting Systems – Daylighting● Efficient A/C units, Boilers, Motors, Light Fixtures● Computers and Office Equipment
Step 3 – Effective Building Operations● Proper Control – Energy Management Systems● Commissioning – Making it work● Operations and Maintenance – Training and Tune-ups● Leverage Utility Company Rate Schedules
Step 4 – Alternative Energy Sources● Renewable Energy Options – Solar, Wind, Biomass
What Is Geothermal Energy?
Geothermal Energy is defined as “energy from the internal heat of the earth”
● 47% of the incoming radiation from the sun is absorbed by the earth
● The remainder is absorbed by the atmosphere or reflected back into space
Translated: Geo-Thermal means “Earth-Heat”
“High Temperature” Geothermal Energy● Energy Source for Hot springs and geysers● Temperatures exceed 300°F● Converted to produce useable heat and electricity
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“Low Temperature” Geothermal EnergyHeat Energy contained near the surface of the Earth
Shallow Earth temperatures fluctuate with seasonal outside air temperature
Nearly constant Earth temperatures at depths below 15 feet
Temperatures start to increase at depths below 400 feet about 1 °F per 100 feet
Ground Surface5 Foot Depth
10 Foot Depth15 Foot Depth
Low Temperature Geothermal Energy
Geothermal Heat Pump Systems● Take advantage of “Low Temperature” Geothermal Energy
● Constant Temperature Year Around – 50 to 55°F in Iowa● Apply a Water Source Heat Pump to “amplify” the heat energy
AKA● Ground Source Heat Pumps● Earth Coupled Heat Pumps● GeoExchange Systems● Well/Ground Water Heat Pumps● v.s. High Temperature Geothermal
Courtesy IGSHPA
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COOLING MODE
CONDENSERHEAT
EXCHANGER
COOLSUPPLY AIR
COMPRESSOR
EVAPORATOR HEAT EXCHANGER
EXPANSIONVALVE
FAN
WARM RETURN AIR
CIRCULATING PUMP
GROUND HEAT EXCHANGER
Heat Pumps Use a Refrigerant Cycle
● Same operation as a Refrigerator or Air Conditioner
● Compressor works to “pump” the refrigerant from “cold” to “hot”
● Heat Energy is transferred through Heat Exchangers
● The addition of a Reversing Valve allowsthe heat pump to work “backwards”
● In Heating Mode – heat is pumped into the space rather than out
Pump Heat rather than creating heat by burning fuel
What are Heat Pumps?
Characterized by Type of Heat Source and Heat Sink● Air to Air or Air Source● Water to Air or Water Source● Water to Water● Ground Source or Geothermal
Capable of Heating, Cooling and producing Hot Water● Capacity measured in tons
● One ton of capacity = 12,000 BTU per hour
● Typical new home is about 4 tons of heating capacity & 2 tons cooling
● Typical Classroom is about 2 – 3 tons of heating or cooling capacity
What is a BTU?
What are Heat Pumps?
6
Geothermal Heat Pump System
Heating/Cooling Delivery System● Traditional Ductwork / Piping system to deliver
heat throughout the building
Heat Pump● Mechanical Unit that moves heat from the working
fluid, concentrates it, and transfers the heat to the circulating air
Ground Heat Exchanger● Underground piping system that uses a working
fluid to absorb or reject heat from the ground
Three Basic Components:
Geothermal System TypesClosed Loop System● Buried HDPE Piping● Underground Heat Exchanger ● Circulating Fluid contained● Exchanges only Heat with
the Ground● Various Configurations
Open System● Ground Water from Well● Exchanges Heat and Water with
the Ground● Returns Water to the Ground● Direct Circulation – Lake or River
Special Systems► City Water Interconnect Systems► Hybrid Systems
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Horizontal Trench LoopCost effective when land area is plentiful
Needs 2500 square foot Land area per ton
Trench depth – Six feet or moreGEOTHERMAL PIPE
To Produce 1 ton of capacity:● Trench length – typically 300 feet● Pipe length – out & back = 600 feet
Courtesy IGSHPA
2 inch Headers
3 Circuits
Horizontal LoopThree Circuits – each with Four Trenches and 4 pipes in each trench
Nominal 24 Ton Arrangement
12 Horizontal Trenches Each 300 foot long with Four ¾ inch pipes
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Slinky Loop
Slinky Coil – Overlap
Slinky Coil – Extended
To Produce 1 ton of capacity:● Trench length – typically 125 feet● Pipe length – out & back = 700 – 800 feet
Courtesy IGSHPA
Slinky Loop
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Vertical Bore LoopKeeps Space required to a minimumNeeds 250 Square Feet Land area per tonBore Depth – 100 to 300 feetBore Diameter – about 4 to 5 inchesBore Spacing – 15 to 20 feet apart Nominal Capacity – One ton / 200 ft Bore Hole
Vertical Boring Methods
Courtesy IGSHPA
10
Vertical Boring Methods
Courtesy IGSHPA
Vertical Bore GroutingGrouting of Vertical Bore Holes Required● Seal Borehole to Protect
Underground Aquifers
● Maintain Thermal contact between pipe and ground
● Allow movement of pipe
Grout Types● Bentonite Based● Thermally Enhanced● Cement Based
Pressure Grouting from the bottom up recommended
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Vertical Loop2 inch Header Pipes
Nominal 24 Ton Arrangement200 foot Deep Vertical Bores with ¾” Pipes
3 Circuits with 8 Bores each Circuit
Horizontal BoreHorizontal / Directional Boring Machine used
● Horizontal length typically 200 feet for one ton of capacity
● Bore depth controlled at depth ~ 15 feet
● Possible to stack horizontal bores at various depths
● Minimal disturbance to topsoil and landscaping
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Horizontal Bore
Pond LoopMost Cost Effectiveclosed loop design
Pond Depth – 12 – 15 ft minimum maintained depth
Pipe Length – One 300 ft. coil per ton (minimum)
Nominal Capacity –● Heating: 10 tons/acre of pond● Cooling: 20 tons/acre of pond
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2 Tons
3 Tons
4 Tons
Pond Loop
Pond Loop Installation
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Open LoopMost Energy Efficient System Option
Very Cost Effective, providingthe following are verified:● Water Quality is High
● Water Quantity is Sufficient
● Meets Codes and Regulations
AKA “Pump and Dump”● 1.5 to 2 GPM per ton required
● At 30% run time a 4 ton unit could use 100,000 gallons per month
● Typical Family of Four uses about 6,000gallons per month for domestic purposes
EnergyPros and Cons
Geothermal System Features
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Geothermal System Features
Energy Pros+ Geothermal Heating Contribution
● 1 kW electricity plus 3 kW geothermal heat moved from the earth = 4 kW heat delivered
● Heating COP of 3.5 to 4.9
+ Geothermal Cooling Contribution● Earth temperature sink cooler than air temperatures
= reduced cooling compressor work● Cooling EER of 14 to 27 (on 2 speed units)
+ Individual units allow zoning for off hour use
+ Reduced energy consumption: 30% - 50% less
+ Lower energy costs: 20% - 30% less
Geothermal System Features
Energy Cons− Economizer Free Cooling not normally available
− Ventilation/make up air energy handled separately
Energy Considerations= Distinction between EER and SEER
= Minimize Circulating Pump energy
= Evaluate Heat Recovery Options for Outside Air / Ventilation Air
16
Energy ConsiderationsHeat Pumps – Ground Source● Heating Efficiency measured by COP (Coefficient of Performance)● Cooling Efficiency measured by EER (Energy Efficiency Ratio)● Performance ARI/ASHRAE/ISO Certified at Specific Temps and Conditions
What are the Actual Entering Water Temperatures?
2.9
3.6 +
4.9
Closed LoopCOP @ 32°F EER @ 77°F
10.6
16.0 +
27.0
11.83.1Low Efficiency
20.0 +4.6 +High Efficiency
31.15.5Best Available
Open LoopCOP @ 50°F EER @ 59°F
Efficiency RatingARI / ASHRAE / ISO 13256 - 1
One point COP improvement represents 3% annual heating cost
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Sunday,January 25,
2004
Monday,January 26,
2004
Tuesday,January 27,
2004
Wednesday,January 28,
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Thursday,January 29,
2004
Friday,January 30,
2004
Saturday,January 31,
2004
Tem
pera
ture
- D
eg F
GeoEx_LWST GeoEx_LWRT OA_Temp
Outside Air Temp
Supply Temp
Return Temp
40.0 Deg F
34.6 Deg F
Geothermal System EWT – Winter
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Energy Considerations
Circulating Pump Energy● Pumping Energy Can Be Significant due to 24 / 7 Load Factor
● Minimizing Pump Head effective ● Many Geothermal Systems have excess Pumping Energy
● Circulating Pump Monitored Energy Use:− Represents 8 % of the HVAC Metered Peak Demand
− Consumes 36 % of the Total Building HVAC Energy
− Responsible for 18 % of the Total Building Energy Costs
► Evaluate Pumping Options● Decentralized Loop Distribution● Two stage parallel pumping● Variable Flow pumping w/VFD’s
Operation and Maintenance
Pros and Cons
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Operation and Maintenance Pros
+ Unitary equipment – failure of one unit
+ Simple, not complex – Reduces Service Contracts
+ Avoids Boiler, Condensing Units or Cooling Towers
+ Elaborate Control Systems not required
+ No annual Boiler Teardown and Inspections
Geothermal System Features
Geothermal System Features
Operation and Maintenance Cons− Quantity of units to maintain
− Heat pump locations accessible
− Air filters and drain pans (unitary)
O & M Considerations= Refrigerant 22 vs 410A
= Equipment/compressor service life of 19 years
= Looping piping service life of 50 + years
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Environmental
Pros and Cons
Geothermal System Features
Environmental Pros+ More comfortable indoor environment
> Each unit operates independently, allowing either heating or cooling to occur as required
> Individual Room Control
+ No make up water for Boiler / Cooling Tower
+ No Chemical Treatment / Hazardous Materials
+ Eliminate Carbon Monoxide (CO) Potential
+ No Vandalism or Security Concerns
+ Minimal floor area required
+ Less energy means less natural resources and less pollution
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Geothermal System Features
Environmental Cons− Noise inside building
Environmental Considerations= Selection of circulating fluids
= Temporary disturbance of landscaping
= Design for proper indoor air quality
Where does a
Geothermal System
Apply?
21
Geothermal Applications
New Construction● Integrate GeoExchange into design
● Optimize system efficiency and costs
Retrofit Construction● Air condition existing non A/C building
● Replace Unit Ventilators or Fan Coil Units
● Minimum disturbance for Historical Preservation
Geothermal Applications
Building Type● Good application:
+ Single-story – finger plan
+ Balanced envelope / interior thermal loads
● Weak application:− New well insulated multi-story “box” with high internal loads
● Residential+ Excellent application
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Geothermal Applications
Schools are Good Candidatesfor Geothermal Heat Pump Systems
Retrofit older systems
Air conditioning upgradeSchool building layout normally good for balanced
heating/cooling loads
Typical classroom good economic size for heat pump
Open field area available for Geothermal Heat Exchanger
System advantages attractive to schools
Schools will be around to enjoy the life cycle cost benefits
Geothermal ApplicationsDomestic Water Heating Options● Cooling Season = Free water heating● Heating Season = High COP water heating
Desuperheater Option● Uses 10 – 15% of Capacity to heat water● Only works when Heat Pump in operation● Unable to satisfy all hot water requirements
Switchover or Demand Option● Uses full Capacity to heat water● Switches from space to water heating● Can satisfy all hot water requirements
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Geothermal Applications
Water to Water Heat Pump Applications● Able to heat water to 120°F
● Dedicated Domestic Water heating
● Hydronic systems
● Radiant floor systems
● Heating water/chilled water source for Outside Air/ Ventilation Air with conventional air handling systems
● Swimming Pool water heating
Radiant Floor Heating Application
Radiant Floor
● Circulate heated water through piping circuits embedded in floor slab
● Warm Floor radiates heat to the walls, ceiling and other objects
● Water to Water Heat Pumps provide water at an effective temperature
Photo by Jeff Benz
24
Geothermal System Economics
$ First Costs+ Energy Costs
+ Maintenance Costs
= Bottom Line
What is the Iowa Experience?
Heating/Cooling Delivery System● No significant difference in the traditional
ductwork system
● Installed ductwork costs are similar
Heat Pump● Compare to premium efficiency Furnace and
Outside Condensing Unit – Tradeoffs
● Installed unit cost premium of about $2,500 compared to a premium furnace & A/C in a typical new home (4 ton capacity)
Ground Heat Exchanger● Dependent on the soil type and system capacity ● ~ $1,400 to $1,600 per ton for simple residential ● Gross cost of about $6,000 for 4 ton system● Credit Utility Rebates -- $0 to $2,400● Tax Credit = 30% of qualified expenditures
First Cost Basics - Residential
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Commercial Building Costs● Building and HVAC System Criteria drive First Costs
● Generally, the cost inside the building is comparable
● Incremental Cost of Geothermal Heat Exchanger vs cost of Boiler, Chiller, Cooling Tower, Condensing Units, etc.
Manage the Installed Cost● Reduce the total Heating / Cooling Load
− Efficient Building Envelope− Efficient Lighting System− Outside Air Loads: CO2 / DCV and Energy Recovery Units
● Right Size the Heating/Cooling Equipment
● First Cost is greatly influenced by Effective Design
First Cost Basics - Commercial
First Costs – Bore Field
$ 13.00 / BoreFt$ 8.00 - $16.00 / BoreFtCost per Foot of Bore:
$ 2,950 / Bore$1,500 - $4,200 / BoreCost per Bore:
$ 2,430 / Ton$1,200 - $3,500 / TonCost per Ton:
$ 5.40 / SqFt$4.50 - $7.00 / SqFtCost per Square Foot:
AverageRangeGross Bore Field Cost
These are project reported bore field gross construction costs ● The costs are not qualified for scope or normalized for conditions● Costs do not include Credits for Boilers, Chillers, Cooling Towers● Costs do not include Utility Company Incentives● Recent Average cost cover last 3 years and include several long horizontal bore projects● Additional Project Cost Information appreciated
Summary Unit Gross Costs
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Typical Bore Field Costs breakdown:● Bore hole drill rig and labor: $6.00 -- $10.00 / bore foot
− Soil type, Field conditions● Prefab U-bend pipe: $0.70 -- $2.00 / bore foot
− Pipe size and thickness● Grout and sand materials: $0.65 -- $1.25 / bore foot
− Bore hole size and Grout type
● Total for bore hole installed: $7.35 -- $13.25 / bore foot
● Multiplier for header systemmanifold, vault, flush, fill, test, etc: 10% to 30%
● Total system cost: $ 8.10 -- $ 14.60 / bore foot● Average cost: ~ $ 13.00 / bore foot
First Costs – Bore Field
First Cost Considerations
Recognize All System Related Cost Savings● Boiler Stacks and Roof Penetrations
● Boiler Room Combustion Air
● Chemical Treatment, Make Up Water and related equipment
● Structural Cost for Cooling Tower or Equipment Support
● Screen Walls and Fences for Vision, Vandalism, Security
● Machine Room (Refrigerant) Ventilation
● Natural Gas Service Entrance
● Reduced Mechanical Equipment Floor area
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First Cost ConsiderationsUtility Company Incentives● $ 0 to $ 600 per ton● $100 to $150 Bonus for High Rated COP and EER● $100 for Desuperheater Option● Custom Incentive Programs● Alternate Rate Schedules● Check with the Local Utility before Design
Financing Options● Iowa Energy Bank Loan● Utility Company Financing● Energy Savings or Performance Contracting
Tax Incentives● Residential: Personal Tax Credit of 30% of qualified expenditures● Business: Corporate Tax Credit of 10% of expenditures● Commercial: Up to $1.80 per SF for 50% better than Energy Standard
Energy Costs
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Energy Costs
All Electric / Electric Heat Rate Schedule● Most Significant Factor for Energy Costs
● Identify the applicable Rate Schedule
● Electric Costs of 4 ¢/KWH vs. 8 ¢/KWH for winter usage
● Some Rates may be applied to the total building electrical usage
Electrical Demand – Commercial Buildings● Typical Reduction in Electrical Demand
● Demand Limiting / Load Shedding Opportunities
● Demand may be a significant factor in total electric costs
Heating Energy EquivalentsEnergy Source Energy Energy Energy Typical Application
Fuel Type Unit Unit Cost Content$ per Unit BTU per Unit
Natural Gas Therm $1.17 100,000 92% AFUE Furnace 12.72$ New Hi Eff Natural Gas Furnace 1,314$ Therm $1.17 100,000 75% AFUE Furnace 15.60$ Older Natural Gas Furnace 1,612$
Propane Gallon $2.21 91,600 92% AFUE Furnace 26.22$ New Hi Eff Propane Furnace 2,710$ Gallon $2.21 91,600 70% AFUE Furnace 34.47$ Older Propane Furnace 3,562$
Fuel Oil Gallon $2.65 139,000 85% AFUE Furnace 22.43$ New Fuel Oil Furnace 2,318$ Gallon $2.65 139,000 65% AFUE Furnace 29.33$ Older Fuel Oil Furnace 3,031$
Electricity KWH $0.10 3,412 1.0 COP Resistance 29.31$ Baseboard Resistance Heat 3,029$ Higher Rate KWH $0.10 3,412 8.0 HSPF Heat Pump 12.50$ Air Source Heat Pump 1,292$
KWH $0.10 3,412 3.6 COP Geo Heat Pump 8.14$ Hi Eff Geothermal Heat Pump 841$
Electricity KWH $0.05 3,412 1.0 COP Resistance 14.65$ Resistance Heat 1,515$ Lower Rate KWH $0.05 3,412 8.0 HSPF Heat Pump 6.25$ Air Source Heat Pump 646$
KWH $0.05 3,412 3.6 COP Geo Heat Pump 4.07$ Hi Eff Geothermal Heat Pump 421$
Shelled Corn Bushel $3.89 392,000 75% Hi Eff Corn Furnace 13.23$ HiEff Corn Furnace (15% Moisture) 1,367$
Wood Cord $125.00 20,000,000 20% Standard Fireplace 31.25$ Tight Packed Cord (4'Hx2'Dx16'L) 3,230$ Hardwood Cord $125.00 20,000,000 40% Franklin Wood Stove 15.63$ Hardwood Dried @ 8,500 BTU/lb 1,615$ Air Dried Cord $125.00 20,000,000 70% Hi Eff Wood Furnace 8.93$ Annualized Efficiency Considered 923$
Example Residence:Design Heat Loss of Building: 53,000 BTU per Hour Calculated from Area and R-Values of walls, roof, windows, etc. - 53,000 BTU/Hr is average new Iowa home (1760 SF).
Annual Heating Degree Days: 6,500 HDD per year Weather Data representing the "coldness" of the winter season - 6,500 HDD is an averge HDD value for Central Iowa.
Annual Heating Energy Req'd: 103.4 Million BTU per Year with an predicted cost of
$/Million BTU
HeatingEquipmentEfficiency
Predicted Cost for Example ResidenceHeating $ per Year
Net HeatingEnergy Cost
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Energy Costs
Case Studies – Ankeny Elementary Schools
● Actual Site Energy Reduction: 46% to 54% BTU/SF-Yr
● Actual Energy Cost Reduction: 6% to 14% $/SF-YrNon Air Conditioned to Air Conditioned
● Energy Cost Avoidance: 20% to 34% $/SF-Yr
Site Energy Use Index – Ankeny Schools
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
Southeast Crocker East Northwest Terrace Westwood Northeast Parkview Northview AnkenyHigh
Site
EU
I, B
TU /
sq. f
t. yr
.
42% Reduction
83,187 BTU/SF-yr Average Conventional System
48,468 BTU/SF-yr Average Geothermal System
30
0.00
20.00
40.00
60.00
80.00
100.00
120.00
140.00
Southeast Crocker East Northwest Terrace Northeast Westwood Parkview Northview Ankeny High
Ener
gy C
ost I
ndex
, ¢ /
sq. f
t. yr
.
62.2 ¢ /SF-yrAvg. Geothermal System
112.7 ¢ /SF-yrAvg Conventional System
45% reduction
Energy Cost Index – Ankeny Schools
Geothermal Heat Pumps From a
Residential Perspective
What are the Energy Efficiency
Alternatives ?
31
Average Iowa Home
1760 Square Feet + Lower Level
Heating Equipment Capacity:● Winter Heat Loss of 53,000 BTU/Hr● 70 °F inside / -10 °F outside● Central Iowa – 6500 Heating Degree Days
Cooling Equipment Capacity● Summer Heat Gain of 21,300 BTU/Hr● 75 °F inside / 95 °F outside● Central Iowa – 1100 Cooling Degree Days
Installation Options
Low Efficiency● 80 % Natural Gas Furnace● 80,000 BTUH Input / 64,000 BTUH Output● 2 ton – 11 SEER Central Air Conditioner
High Efficiency● 92 % Natural Gas Furnace● 60,000 BTUH Input / 55,200 BTUH Output● 2 ton – 13 SEER Central Air Conditioner
Geothermal Heat Pump System● 4 Ton Geo Heat Pump – 4.0 COP w/ 5 KW auxiliary heat● 41,000 BTUH Input / 58,000 BTUH Output w/ aux heat● 4 ton cooling at 18.0 EER
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HVAC System Costs
HVAC System Cost Low Efficiency High Efficiency GeothermalGas / Cent Air Gas / Cent Air Heat Pump
Base HVAC Equipment: 53 MBH / 24 MBH 66 MBH/2 Ton 60 MBH/2 Ton 4 Ton Heat/2 TonBase Equipment Cost 2,500$ 3,500$ 6,000$ Ductwork, Accessories & Installation 6,000 6,000 6,000 Geothermal Heat Exchanger and Circ Pump or 1,200 1,200 7,000 Gas line, Flues Vents, Refrig LinesOptions: Energy Recovery Ventilation 2,000 2,000 2,000 Humidifier, Premium Filter, Exhaust Fans 1,200 1,200 1,200 Total Amount 12,900$ 13,900$ 22,200$
Utilty Company Rebates 0 250 2,100
Net HVAC System Installed Cost 12,900$ 13,650$ 20,100$
Percent Increase OR Existing Retrofit 6% 47%
Above does not include Tax Credit of 30% or about $6,000
Energy Use and Cost
Electric Heating Rate of 6¢ per KWH on use over 1,000 KWH/Mo
Energy Low Efficiency High Efficiency GeothermalGas / Cent Air Gas / Cent Air Heat Pump
Natural Gas - Winter Heating $1.25 per Therm Base Energy KWHElectric Rate - Winter Heating $0.06 per KWH 1,000 Electric Rate - Summer Cooling $0.09 per KWH $0.09
Heating AFUE/COP 80% 92% 3.6Cooling SEER/EER 11.0 12.0 18.0$ / Million BTU $15.63 $13.59 $4.88
Base Energy - First KWH = 1,000 1,080$ 1,080$ 1,080$ Annual Heating Cost 1,612 1,402 504 Annual Cooling Cost 230 211 141 Total Annual Cost 2,922$ 2,692$ 1,724$
Average Monthly Cost $243.49 $224.37 $143.71
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Acquisition Low Efficiency High Efficiency GeothermalGas / Cent Air Gas / Cent Air Heat Pump
Base Construction @ $ / SF = $125 220,000$ 220,000$ 220,000$ Net HVAC System Installed Cost 12,900$ 13,650$ 20,100$ Purchase Price 232,900$ 233,650$ 240,100$ Down Payment 25,000$ 25,000$ 25,000$ Loan Amount 207,900$ 208,650$ 215,100$
Monthy Payment
Annual Interest Rate %/yr 6.40% 6.40% 6.40%Term in Months 360 360 360
Principal and Interest 1,300.43$ 1,305.12$ 1,345.46$ Taxes 200.00$ 200.00$ 200.00$ Insurance 50.00$ 50.00$ 50.00$ Energy 243.49$ 224.37$ 143.71$
Total Monthly Payment 1,793.91$ 1,779.49$ 1,739.17$
Monthly Energy Penalty (54.74)$ (40.32)$ -$
Total Monthly Cost – PITI + Energy
Economic PerformanceBottom Line● Most Energy Efficient Heating & Cooling System Available
● Comfortable with a High Degree of Owner Satisfaction
● Reduces Energy Cost by 20% to 35%
● Adds 2 – 4% to the Total Cost of New Construction
● Incentives, Credits and Alternate Financing may be Available
● Typical 5 to 12 year payback
● Generally Best Life Cycle Costs
● Considering PITI & Energy…… $40 to $50 monthly Cost Penalty
to use Conventional System
Each Commercial / Residential Facility is Unique
34
May 6 – 8, 2009
Introduction to Geothermal Heat Pump Systems
Thank You…….. Discussion ! ! ! !
Questions ????
Energy Resource Station at DMACCPhone: 515-965-7055
curtk@energy.iastate.eduwww.energy.iastate.edu
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