Post on 28-Jul-2015
transcript
Commercial Design for Commercial Design for
Geothermal SystemsGeothermal Systems
STARTING OUT RIGHTSTARTING OUT RIGHT
Develop a design team.Develop a design team.
Examine site for best loop options.Examine site for best loop options.
Determine building zone loads and block loads.Determine building zone loads and block loads.
Select loop length with software - individual loop Select loop length with software - individual loop or peak block load.or peak block load.
Select pump for single unit or central pump Select pump for single unit or central pump design.design.
Zone load determines unit selection for space. Zone load determines unit selection for space.
Block heating/cooling load determines loop length. Block heating/cooling load determines loop length.
Hybrid design should be considered on jobs with Hybrid design should be considered on jobs with excessive gains (rejection). excessive gains (rejection).
Fresh air may require special considerationsFresh air may require special considerations
–Hot Water ReheatHot Water Reheat
–Water to Water with hydronic coilWater to Water with hydronic coil
–Heat Recovery equipmentHeat Recovery equipment
BUILDING LOSS / GAINBUILDING LOSS / GAIN
Vertical, Horizontal, Downflow, Console, Rooftop, Vertical, Horizontal, Downflow, Console, Rooftop, Water to Water, and Split configurations Water to Water, and Split configurations available.available.
Design using equipment rated to match loop Design using equipment rated to match loop temperatures.temperatures.
Select equipment using 35°F EWT for heating and Select equipment using 35°F EWT for heating and 95 to 100°F EWT for cooling.95 to 100°F EWT for cooling.
Design airflow approximately 400 CFM per ton.Design airflow approximately 400 CFM per ton.
Design geothermal closed-loop water flow rate Design geothermal closed-loop water flow rate 2.5 to 3 gpm/ton.2.5 to 3 gpm/ton.
GEOTHERMAL UNIT SELECTIONGEOTHERMAL UNIT SELECTION
Vertical3/4 to 20 ton
Horizontal3/4 to 10 ton
Water-to-Water1 to 30 ton
PRODUCT LINEPRODUCT LINE
Console1/2 to 1-1/2 ton
Rooftop3 to 22 ton
HEAT SOURCE & SINKHEAT SOURCE & SINK
BOILER/COOLING TOWERBOILER/COOLING TOWER
OPEN LOOPOPEN LOOP
CLOSED LOOPCLOSED LOOP VERTICALVERTICAL HORIZONTALHORIZONTAL PONDPOND
BOILER/COOLING TOWER
Excellent for buildings where space is not Excellent for buildings where space is not available for a closed loop system.available for a closed loop system.
Cooling tower can be used in conjunction Cooling tower can be used in conjunction with a closed loop for a very cost-effective with a closed loop for a very cost-effective system for cooling-dominant applications.system for cooling-dominant applications.
High efficiency geothermal equipment High efficiency geothermal equipment enhances operating cost savings of an enhances operating cost savings of an already proven technology.already proven technology.
BOILER/COOLING TOWER
OPEN LOOP
OPEN LOOP
Very cost effective, provided the following Very cost effective, provided the following are verified:are verified:
–Water quality is highWater quality is high
–Water quantity is sufficientWater quantity is sufficient
–Discharge location is availableDischarge location is available
–Meets codes/standardsMeets codes/standards
VERTICAL LOOP
Keeps space needed for a closed loop to a Keeps space needed for a closed loop to a minimum.minimum.
Requires 250 square feet of surface area per ton.Requires 250 square feet of surface area per ton.
Each bore 180 to 300 ft. deep depending upon Each bore 180 to 300 ft. deep depending upon application and climate (use software).application and climate (use software).
Holes filled and sealed with grout. Holes filled and sealed with grout.
Most expensive first costs - $1,000 to $1,300 per Most expensive first costs - $1,000 to $1,300 per ton.ton.
VERTICAL LOOP
VERTICAL LOOP
Circuits
Runouts
Geo-ClipsGeo-Clips
Devices used to keep pipe separated in bore Devices used to keep pipe separated in bore hole for optimum performance.hole for optimum performance.
Vertical Loop Installation
Loops Installed Under Baseball Field at High School
Cost effective when land area is plentiful.Cost effective when land area is plentiful.
2500 sq. ft. per ton required.2500 sq. ft. per ton required.
Various methods and piping arrangements, Various methods and piping arrangements, depending upon available space.depending upon available space.
200 to 400 ft. of trench per ton, depending 200 to 400 ft. of trench per ton, depending upon climate and loop type.upon climate and loop type.
Installed costs - $600 to $800 per ton.Installed costs - $600 to $800 per ton.
HORIZONTAL LOOP
RUNOUTSCIRCUITS
HORIZONTAL LOOP
POND LOOP
Pond depth 10 to 12 feet minimum.Pond depth 10 to 12 feet minimum.300 to 350 feet of 3/4 inch P.E. coil per ton.300 to 350 feet of 3/4 inch P.E. coil per ton.30 to 50 tons of 30 to 50 tons of coolingcooling per surface acre. per surface acre.10 to 20 tons of 10 to 20 tons of heatingheating per surface acre. per surface acre.Northern projects favor mat loops.Northern projects favor mat loops.$400 to $700 per ton.$400 to $700 per ton.
POND LOOP
2 Tons
3 Tons
4 Tons
POND LOOP
Coil spacers increase thermal performance.
Pond loop assembly
Vertical:Vertical: - GchpCalc by Steve Kavanaugh- GchpCalc by Steve Kavanaugh
–GLHEPRO by Oklahoma State.GLHEPRO by Oklahoma State.
Horizontal: -WrightSoft (residential software).Horizontal: -WrightSoft (residential software).
Pond Loops: - Use consultant (Loop Group).Pond Loops: - Use consultant (Loop Group).
Software patterns heat transfer to and from soil Software patterns heat transfer to and from soil (storage) to account for long term effects.(storage) to account for long term effects.
Conductivity Testing Recommended.Conductivity Testing Recommended.
Thermally enhanced grouts available.Thermally enhanced grouts available.
LOOP SIZING SOFTWARELOOP SIZING SOFTWARE
CENTRAL PUMP STATION
SUCTIONFROM CLOSED LOOP
EXPANSION TANK
SUCTIONDIFFUSER
TRIPLE DUTY VALVE
CENTRIFUGAL PUMP
DISCHARGETO CLOSED LOOP
AIRSEPARATOR
CENTRAL PUMP STATION
INSIDE PIPING
Central Pump
Core Units
Perimeter Units
INSIDE PIPING
Commercial & Institutional InstallationsCommercial & Institutional Installations
Offices Offices Schools and UniversitiesSchools and UniversitiesRetail, Restaurants, MallsRetail, Restaurants, MallsHotels, Motels, ResortsHotels, Motels, ResortsApartments and CondominiumsApartments and CondominiumsHospitals and Health CareHospitals and Health CareScience Centers and MuseumsScience Centers and MuseumsPools, Greenhouses and Fish FarmsPools, Greenhouses and Fish Farms
Offices
Schools
Hotels & Resorts
Multi-Family & Military Housing
And many other types of applications including restaurants, retail, pools, hospitals, museums, nursing homes...
Contact WFI Commercial Department for Design
Assistance