Design, Analysis & Cost Development of a 220 Ton Geothermal HVAC System

1. Design, Analysis & Cost Development of a 220 Ton Geothermal HVAC System Albert A. Koenig, Ph.D. ARB/Geowell Systems www.ARBgeowell.com

2. Presentation Outline • L.E.E.D. Building Design (Silver) Goals • Load Modeling/Simulation • HVAC Distribution Technology • Hydronic System Scheme • Site Information • Load Design Spec • The GeowellTM SCW Technology • GeowellTM String Deployment • 220 Ton Geothermal Field Layout • Installed Cost & Payback

3. Building Design Standard • Basis: ASHRAE/IESNA Standard 90.1-2004 for building energy efficiency/sustainability and Standard 62 for ventilation • Bldg. envelope & systems designed to maximize energy performance, based on • Computer simulation model (DOE-2, TRACE) • Identification & implementation of the most cost-effective energy efficiency measures • Quantification of performance vs. baseline bldg. • 20% renewable energy credit: geothermal

4. Building Operating Expense (lighting, HVAC, electricity) (Productivity)

5. Building Interior Daylighting

6. DOE-2: Model Bldg. Hourly Energy Use

7. Silver L.E.E.D. Design Goal Targets: • 280 KBTU/sqf =>180 KBTU/sqf annual energy use • HVAC equipment: 250 tons => 180 tons Equipment: • Innovative active chilled beam ceilings for integral room comfort using geothermal chilled water to provide 15°F ΔT (floor to ceiling) • 73% efficient economizer with energy recovery wheel

8. Exposed Chilled Beam TechnologyEsp. Suited for Open Office Areas

9. Chilled Beam Bldg. Heat Transfer

10. Hydronic System Diagram Ground Water Source

11. Building External HVAC Load: HDD/CDD

12. Building HVAC Design Spec • 80,000 sqf office building (7 floors) • 220 tons (365 sqf/ton) • Building Load: • External Load: 92 tons • Internal Load: 128 tons (lighting, people, equipment & air transport)

13. 20 acres wooded area (NJ/NY) Proximity to river for ground water recharge Ample water well records in vicinity Water 50-60’ from surface Excellent hydrogeology for geothermal application Site Information

14. Rock Thermal Properties Site Geology: dolomite

15. Seasonal Heat Storage Measurement & Modeling/Simulation @ 50’/ton

16. ARB/Geowell Technology A New Old Approach for Using Geothermal Water Wells for Building HVAC

17. Water Supply/Return Heat Propagation Water Well Operation with Re-injection Wellbore Heat Transfer

18. Patented in-Well String Design for Fast Deployment & Maintenance Pump Discharge to Bldg. HX Pump Housing @ 80' Depth Pump Extension Lines Slitted Water Entryway Concrete Guide 800' Bottomhole Depth

19. GeoWell SCW Cross Section Upcoming Supply Water 6" Wellbore Insulated Polypipe Thermal Return Water Heat Transfer Rock formation Heat flow Thermal zone

20. Impact of Polypipe Insulation on Wellbore Heat Transfer Smooth Wall Rough Wall

21. Heat Transfer Benefit of GeowellTM: 4-Fold Improvement Over Closed Loops

22. The ARB/Geowell Technology Patented SCW technology that insure: • minimal geofield installed expense • use of deep (nom. 1000’) wells to minimize footprint and the number of submersible pumps • the entire 6” wellbore diameter and length are utilized in return water heat exchange • minimal total drilled length to satisfy bldg. load specification • fast installation of each well string • minimal field installation time (pre-fab ext. plumbing) • minimal operating expense • minimal parasitic power utilization by employing a control algorithm that activates on those well pumps that are needed to satisfy the load • well strings designed for ease of pump replacement

23. 800' polypipe reels Cemented casing Water level Wellbore Laminar flow slits Debris baffle Concrete weight Capped polypipe embedded Fast In-Well Deployment

24. GeoWellTMSubmersible Pump Housing and Docking Assembly

25. GeoWellTMInjected Molded Components

26. Geowell Advantages

27. Applications 220 Ton Geothermal Field Layout

28. Bldg. Return 135' Bldg. Supply 105' 220 Ton Geowell Field Layout

29. 220 Ton Design Specification • Based on drilling to a nom. depth of 800’ • 20 water wells, operated 4 rows x 5 wells per row, or 5 x 4 • Well-well spacing 30’ • Footprint: ⅓ acre • Installed cost: $211,800

30. Field Plumbing Schematic Well & Pump Pre-fab Stepped Pipe Header Return Water Ctrl Valves Municipal Water Pipe Bldg. HX

31. Installed Cost Breakdown

32. Installed Cost & Payback Geowell Example: 220 ton bldg. load Installed loop (20 wells) price: $286,000 [Heat Pumps (220 tons total): $176,000] less State Rebate ($/ton): ? - $ 77,000 less Fed Tax deduction: - $ 48,000 Net Cost: $161,000 Annual Operating Savings: $ 22,850 Discounted Payback: 6 yrs

33. Discounted Payback Analysis

34. Federal Tax IncentivesEPAct 2005 for Commercial Bldgs. • Tax deduction of up to $1.80/sqf for qualifying property (e.g.$144,000 for a 80,000 sqf bldg.) • Split three parts: ⅓ each for envelope, lighting and HVAC • Fully qualifying property must show (in a simulation) 50% energy & power savings over a reference bldg. that meets minimum Standard 90.1-2001

35. State Rebate ProgramGeothermal GSHP Installations • PA offers only Energy Harvest grant opportunities and Sustainable Development Fund (SDF) loan pool (7-9%) + PECO ($800 installation rebate) • NY: $150-800/ton under LIPA • NJ: $370/ton • DE: $600/ton capped at $25,000