Technology and Engineering Development (TED) Building

1. Technology and Engineering Development (TED) Building Thomas Jefferson National Accelerator Facility Newport News, VA Presentation Overview • Project Background • Site, use, and architecture • Existing Mechanical System • Air system, hydronic system, geothermal system • Horizontal Directional Drilling (Depth 1) • An alternative geothermal solution • Radiant Floor Slab Cooling (Depth 2) • An exploration of slab thermal capacity • Construction Schedules and Costs for Alternatives (Breadth 1) • Presented after each depth • Final Conclusions David Blum | Mechanical Option Dustin Eplee | Adviser Architectural Engineering | The Pennsylvania State University

2. General Building Information Site Architecture Design and Use Size: 70,000 SF Stories Above Grade:Two Project Team Owner: Jefferson Lab CMGC: Mortenson ConstructionA/E: EwingColeCost Consultant: Crawford Consulting Services, Inc Dates of Construction: 8/4/2010 – 9/30/2011 Cost: $16 million Project Delivery Method: Design-Bid-Build • 1st Floor • Research Workspaces • Highbay Area • 2nd Floor • Offices, Conference, and Administration • Health Club, Break Room • Main Mechanical Room Thomas Jefferson National Accelerator Facility Newport News, VA

3. Hydronic System Air System Hybrid Condenser System • Variable Air Volume with Terminal Reheat • AHU 1: 32,000 CFM serves 1st Floor and Highbay • AHU 2: 32,000 CFM, 2nd Floor • Fan Powered Boxes serve perimeter zones • VAV Boxes serve interior zones • 12 Central Water to Water Heat Pumps • Chilled Water: 42 F Supply, 50 F Return • Cond. Water: 85 F Entering, 95 F Leaving • Hot Water: 120 F Supply, 110 F Return • Cond. Water: 55 F Entering, 45 F Leaving • EER: 14 • 10 Chilled Water, 6 Hot Water • Vertical Bore Geothermal • 3 Fields • 192 Wells • 300 ft Depth • Full Heating Load • 72 % Cooling Load • Outdoor Air Pre-Conditioning • OAU 1: 7,500 CFM serves AHU 1 • OAU 2: 6,800 CFM serves AHU 2 • Total Energy Wheel exchanges latent and sensible heat with exhaust • Boiler • Backup heat source • Closed Circuit • Cooler • 28% Cooling Load

4. Existing and Proposed Geothermal Fields Depth 1: Full Load Geothermal Design Field Type • Horizontal Trench • 2500 ft2/ton and $600 to $800 / ft2 • 167,500 ft2 required is too large • Goals • Add field to meet full cooling load: 67 additional tons Existing Proposed • Vertical Bore • 250 ft2/ton and $900 to $1100 / ft2 • 16,750 ft2 required eliminates trees • Minimally invade tree line (per owner) • Compare energy use and first costs to current hybrid condenser system • Horizontal Directional Drilling • Horizontal bores under obstacles • Up to 600 ft long and 45 ft deep • Stacked vertically in ground 176,000 ft2

5. Geothermal Design Layout Energy and Operation • Bores • Total Length: 21441 ft • Length per Bore: 450 ft • No. Bores: 48 • No. Rows:16, 3 stacks (15 ft, 30 ft, 45 ft) • Spacing: 15 ft • Diameter: 5” • Pipe: 1” HDPE • Grout: Bentonite (k = 1.0 hr-ft-F/Btu) • Pumps • 1100 GPM • VFD • Annual Energy Use • Closed Circuit Cooler (1599 hrs): 89,429 kWh • Total Current HVAC: 646,138 kWh • Total Proposed HVAC: 556,709 kWh • Savings: 13.8% • Life Cycle • Operational Savings: -$5,982/ yr • Additional First Costs: $178,096 • Simple Payback: 30 years

6. Installation Process HDD Geothermal Construction Budget and Schedule Impact • Cost • Current Condenser: $756,074 • Closed Circuit Cooler: $51,054 • Vertical Bore Field: $687,936 • Pumps: $17,084 • Proposed Condenser: $934,170 • HDD Field: $229,150 • Difference: +$178,096 (+7.3% HVAC Budget) • Schedule Impact • Field Installation and Equipment Mobilization: 62 Days (~12.5 Weeks)

7. Radiant Slab Implementation Depth 2: Radiant Floor Cooling Slabs Radiant Slab Design Conditions • Goals • Explore the capabilities of floor slab thermal storage Floor Surface Temperature: 68 F Indoor Air: 78 F, 50% RH, 58 F DP 1st Floor • 1st Floor 5” NW Slab on Grade • Covering: Conductive Concrete (ESD) • 3/8“ PEX Tubing Depth: 4” Below Surface • CHWS Temp: 61 F • Analyze cooling capacity and effects on air system • Compare daily cooling energy use and power demand profile with current HVAC system 2nd Floor • 2nd Floor 3 ¼” LW Elevated Slab on Metal Deck • Covering: ¼” Carpet • 3/8“ PEX Tubing Depth: 1 ½” Below Surface • CHWS Temp: 55 F

8. Required Cooling Airflow Load and Energy Model Proposed Systems • Excel Spreadsheet Model • Adapted RSTM method • Hourly slab temperature from heat balance • Radiant Slab System • Distribution Pump: 187 GPM, 7.5 HP • 3 Heat Pumps, EER: 16 • Slabs in series • Parallel Air Systems • AHU 1: 16,825CFM • AHU 2: 15,446CFM • CHW Distribution Pump: 350 GPM, 15 HP • 6 Heat Pumps, EER: 14

9. Daily Energy Use Daily Energy Use by Component Breadth: Radiant Floor Construction • Cost • Current HVAC System: $2,450,000 • AHUs: $372,290 • Pumps: $12,336 • Radiant Slab HVAC System: $2,613,000 (+6%) • AHUs: $185,920 • Pumps: $18,126 • Radiant Floor: $319,625 • Currently Designed System • Radiant Slabs System Peak Demand: Total Usage: Current Design 283 kW 3,725 kWh Radiant Slabs 205 kW 3,238 kWh Savings 27.5% 13.1% • Schedule Impact • 26 weeks with one crew • 2 weeks with Climate Mat

10. Final Conclusions • Geothermal Systems • Hybrid geothermal systems can reduce first costs while still reducing energy use • Horizontal Directional Drilling offers ability to install geothermal fields with little land disturbance • Radiant Floor Slabs • Can be used to flatten demand profile • Controllability becomes important because cooling effect is not instant

11. Acknowledgements A special thank you to the following people and parties that made this project possible: Jefferson Lab, TED Owner EwingCole, Architects, Engineers, and Interior Designers Eric Joesten, Director of Mechanical Engineering, EwingCole Kate Mondock, Mechanical Engineer, EwingCole Dustin Eplee, Thesis Adivsor Mentors on the Thesis Class Discussion Board