Re: College of Lake County: AB Wing HVAC Remodeling Programming Mtg #3 Architect s Project Number: Meeting Minutes

Transcription

1 March 6, 204 VIA College of Lake County 935 West Washington Street Grayslake, Illinois Re: College of Lake County: AB Wing HVAC Remodeling Programming Mtg #3 Architect s Project Number: Meeting Minutes Summary of a Committee Meeting held at :00PM Thursday, March 6, 204 at the College of Lake County. These notes record our understanding of items discussed and decisions made at this meeting. Please notify us within seven (7) calendar days of any necessary additions or corrections. PERSONS IN ATTENDANCE Greg Evans Scott Allen, Jim Marison Erik Solomon Ted Johnson Curt Wagner Sheryl Van Anne Chris Augustyn Dorothy McCarty Ryan Sprangers Michael Lundeen, CLC CLC CLC CLC CLC Mortenson Mortenson AEI Cotter KJWW Legat ITEMS DISCUSSED. The group followed the meeting agenda and meeting goals (attached). Presentation materials attached. 2. The previous presentation was used with a few new slides for discussion. 3. The group discussed questions sent by Jim Marrison and Scott Allen sent to the group. A. Has KJWW completed a project which has Chilled beam system with an Open building or building which is connected to other buildings? Ryan indicated that KJWW has not completed a renovation project utilizing chilled beam for cooling, however Ryan detailed their approach to control humity with a VAV system at akll corridors and entry spaces to buffer/temper the air in the building. B. Discussed envelope testing. The roof to masonry wall may leak a lot of air to the exterior. Group discussed the idea of have a portion or all of the AB wing pressure tested. CLC may consider. Ryan also identified that more detailed energy models during SD will model the actual builsing envelope and R Value.. C. Jim asked that a test be made to determine how much the building leaks. CLC should consider the timing, costs and direct the design team if they are interested in pursuing these tests. D. Scott asked about radiant cooling at floors. Ryan indicated that chilled beam operate similar to radiant floor cooling. To do this the floors would need a 2.topping installed across the entire floors(s). E. Jim asked how the LEED points compare within the systems. Ryan referenced the slide which indicated the estimated LEED points of the systems. F. Jim brought up the potential of using Fan Coil units in the corridors. (Option 4)

2 College of Lake County: AB Wing HVAC Replacement Meeting Minutes March 6, 204 Page 2 of 2 4. Dual AHU and water to air Heat pumps options were pulled off the table. These would not be pursued. 5. Group reviewed the map which depicted the areas separated Chilled beam and VAV. 6. Discussed potential locations of central plan. The central plant would house the water to water heat pumps which will produce hot and chilled water. The group discussed the various options for the central plant: Existing penthouse, lower level of cafeteria, existing space, new penthouse on roof, or other addition. 7. Group discussed the central geothermal and potential timeline. Cotter to look at the schedule to determine the key milestones the geothermal should be operational for the cafeteria or other phases. The wells may only need to be complete for the Cafeteria. 8. Sheryl talked about the differences in energy cost savings verses the construction costs and cost to install the systems. The less energy saved also produces a system which is easier to install in phases. 9. Jim talked about the idea of connecting the controls into the scheduling software. 0. Concerns with the chilled beam. College would need to learn to close the doors. CLC is going to visit other chilled beam installations.. Dorothy presented a chart which depicted long term maintenance cost comparison between the five systems and multiplied over time. A yearly maintenance cost of $0,000 was used chilled beam, $20,000 for Dual AHU, $30,000 for VAV system, $40,000 for FanCoil units, $50,000 for Water to Air Heat pumps. With these values the total maintenance plus installation costs was not very different. 2. Jim indicated that they expect to use 2 maintenance staff to maintain the AB wings plus filters, and other materials. It was suggested the yearly costs may be significantly different than the $0,000-50,000 presented. 3. After discussions and narrowing down the options the group indicated the likely options to consider are either fan-coil concept or Chilled Beam/VAV. 4. Discussed LEED points for energy points. Need minimally 5 of the 9 points. Greg asked that Vuk provide input to how we can get the points. Vuk plans to attend the next meeting to go through LEED. 5. KJWW will look at existing model to determine if Fancoil can fit above the ceilings. 6. Next meeting: A. Discuss LEED and the points to achieve Platinum. B. Further discuss the HVAC options and make a decision which option to be pursued into SD. C. Group decided to meet need Thursday March 3 at PM.. Thank you. Sincerely, Legat Architects, Inc. Michael Lundeen, Senior Project Manager ML/ML ATTACHMENTS CC Agenda Presentation CLC MP Website Jeffrey Sronkoski, Legat Architects Ryan Horsman, Legat Architects Vuk Vujovic, Legat Architects

3 Meeting Agenda ORGANIZATION College of Lake County RE A/B Remodel/HVAC PROJECT TITLE Master Plan Projects PROJECT NO LOCATION CLC-Grayslake Campus, Room A26 DATE, TIME March 6, 204, :00PM. Goals of the Meeting (5min) Confirm all criteria for selecting concepts have been identified Update group on operation costs, Geothermal, Phasing Confirm selection of Concept to be made either March 6 or next meeting 2. General Questions on Systems/Analysis/Site visits (20min) 3. Operation/Cashflow Analysis - Cotter 4. Status of Geothermal project Cotter/AEI (0min) 5. Discussion of HVAC Concept Options (0min) a. Locations of Central Plant (if selected) b. Locations of VAV vs Chilled Beam (if selected) 6. Implementation / Phasing Considerations - Mortenson (0min) 5. Next step (5min) Next Meeting LEED Charette Approval of Concept Programming CC File: AB HVAC /Remodeling FILENAME

4 SYSTEM SUMMARY

5 CLC A&B HVAC System Matrix System Abbreviation: Existing Baseline Dual AHU VAV Heat Pump Fan Coil Unit Chilled Beam System: Existing ASHRAE 90. Baseline Water-to-Water Heat Pumps with DOAS/Cooling Only AHUs Water-to-Water Heat Pumps with VAV AHUs DOAS with Water-to-Air Heat Pumps Water-to-Water Heat Pumps with DOAS/Distributed Fan Coil Units Water-to-Water Heat Pumps with DOAS/Chilled Beams SQFT: 24, , , , , , ,500 Initial Cost/SQFT: $53 $46 $52 $53 $48 Initial Cost: $2,322,500 $0,695,000 $2,090,000 $2,322,500 $,60,000 Gas Usage (therms): 59,098,000,000,000,000,000,000 Gas Cost ($/therm): $0.89 $0.89 $0.89 $0.89 $0.89 $0.89 $0.89 Electrical Usage (kwh): 5,805,000 5,56,000 3,673,000 3,626,000 3,473,000 3,438,000 3,308,000 Electric Cost (kwh): $0.07 $0.07 $0.07 $0.07 $0.07 $0.07 $0.07 Operating Cost: $548, $39, $258, $255, $244, $242, $233, % Comparison to ASHRAE Baseline: % 34.8% 37.6% 38.% 40.4% LEED Points (new/reno): (/3) (2/4) (3/5) (4/6) (5/7) Sound (NC): Scalability: Yes, but geothermal service and space for water-towater heat pump, pumps, etc. needs to be sized for anticipated expansion Yes, but geothermal service and space for water-towater heat pump, pumps, etc. needs to be sized for anticipated expansion Yes, geothermal service just needs to be sized for anticipated expansion Yes, but geothermal service and space for water-towater heat pump, pumps, etc. needs to be sized for anticipated expansion Yes, but geothermal service and space for water-towater heat pump, pumps, etc. needs to be sized for anticipated expansion Maintenance: Water-to-Water heat pump (Assume 500 ton units each * Compressor(s) - /2 of the units will require replacement over the life of the unit * Circuit board - /2 of the units will require replacement over the life of the unit * Control valving - Last life of unit DOAS (Assume total units and 95,000 CFM) * Filter - Quarterly replacement * Fan Motors - Once over life of unit Cooling only VAV (Assume total 6 VAV AHU's) * Filter - Quarterly replacement * Fan Motors - Once over life of unit Water-to-Water heat pump (Assume 500 ton units each * Compressor(s) - /2 of the units will require replacement over the life of the unit * Circuit board - /2 of the units will require replacement over the life of the unit * Control valving - Last life of unit VAV (Assume total 7 VAV AHU's and 268,500CFM ) * Filter - Quarterly replacement * Fan Motors - Once over life of unit Terminal Reheat boxes (Assume total 85 distributed boxes) * Damper and control valves * Circuit Board Water-to-air heat pump (Assume total 85 distributed units) * Filter - Semi-annually replacement * Fan Motor - Once over life of unit * Compressor -/3 of the units will require replacement over the life of the unit Water-to-Water heat pump (Assume(2)@ 500 ton units each * Compressor(s) - /2 of the units will require replacement over the life of the unit * Circuit board - /2 of the units will require replacement over the life of the unit * Control valving - Last life of unit DOAS * Condensate pump (if not by gravity) -Once over life (Assume total units and 95,000 CFM) of unit * Filter - Quarterly replacement * Circuit board - /2 of the units will require * Fan Motors - Once over life of unit replacement over life of unit (5 yr life) Fancoil units maintenance (Assume total 85 units) DOAS * Filter - Semianually replacement (Assume total units and 95,000 CFM) * Fan Motor - Once over life of unit * Filter - Quarterly replacement * Condensate pump (if not by gravity) - once over * Fan Motors - Once over life of unit life of unit * Circuit board - Once over life of unit * Control Valve - Last life of unit Water-to-Water heat pump (Assume 500 ton units each * Compressor(s) - /2 of the units will require replacement over the life of the unit * Circuit board - /2 of the units will require replacement over the life of the unit * Control valving - Last life of unit DOAS (Assume total units and 95,000 CFM) * Filter - Quarterly replacement * Fan Motors - once over life of unit Chilled Beam (Assume 700+ beams) *Clean/Vacuum Coils - Once every 4 years (per manufacturers recommendation) Maintenance Cost: Water-to-Water heat pump * Compressor(s) = $2800 ea. * Circuit board = $525 ea. * Control valving = $25 ea DOAS * Filter - $$$ * Fan Motors - $2000 Cooling only VAV * Filter * Fan Motors -$2500 Water-to-Water heat pump * Compressor(s) = $2800 ea. * Circuit board = $525 ea. * Control valving = $25 ea VAV * Filter - $$$ * Fan Motors - $2500 Terminal Reheat boxes * Damper and control valves = $200 * Circuit Board = $200 Water-to-air heat pump * Filter = $5 merv 3 ea. * Fan Motor = $60 ea. * Compressor = $640 ea. * Condensate pump (if not by gravity) = $25 ea. * Circuit board = $80 ea DOAS * Filter - $$$ * Fan Motors - $2000 Water-to-Water heat pump * Compressor(s) = 2800 ea. * Circuit board = $525 ea. * Control valving = $25 ea DOAS * Filter - $$$ * Fan Motors - $2000 Fan Coil Units * Filter = $5 Merv 3 * Fan Motor = $350 * Condensate pump (if not by gravity) = $25 * Circuit board = $500 * Control Valve = $35 Water-to-Water heat pump * Compressor(s) = $2800 ea. * Circuit board = $525 ea. * Control valving = $25 ea DOAS (Dual wheel unit) * Filter - $$$ * Fan Motors - $2000 Chilled Beam (Assume 700+ beams) *Clean/Vacuum Coils - No material costs Staffing: Anticipated Life/ Replacement Cost: Water-to -Water Heat Pumps: >24 yr / $70/ton (8) System Pumps: 20 yr / $0,000/pump () AHU Coil Pumps: 20 yr / $7,500/pump DOAS: yr / $6/cfm Cooling only VAV AHU's: yr / $4/cfm Water-to -Water Heat Pumps: >24 yr / $70/ton (8) System Pumps: 20 yr / $0,000/pump (7) AHU Coil Pumps: 20 yr / $7,500/pump VAV AHU's: yr / $4/cfm Terminal Reheat boxes: +25yrs / $500/ton Water-to -Air Heat Pumps: >24 yr / $750/ton (2) System Pumps: 20 yr / $0,000/pump () AHU Coil Pumps: 20 yr / $7,500/pump DOAS: yr / $6/cfm Water-to -Water Heat Pumps: >24 yr / $70/ton (8) System Pumps: 20 yr / $0,000/pump () AHU Coil Pumps: 20 yr / $7,500/pump DOAS: yr / $6/cfm Fancoul Units: 20 yr / $,400/unit Water-to -Water Heat Pumps: >24 yr / $70/ton (8) System Pumps: 20 yr / $0,000/pump () AHU Cil Pumps: 20 yr / $7,500/pump DOAS (Dual wheel unit): yr / $8/cfm Chilled Beam: 25+ yr / $/Beam Notes/Assumptions: ) Initial Costs do not include geothermal field costs, additional costs due to phased construction, LEED premiums. Costs are shown as 204 dollars. 2) Additional means of improving efficient/reductin operating costs: - Water cooled kitchen refrigeration equipment via geothermal - VAV outside air using VAV boxes and CO2 sensors - Heat Recovery on the Grease Exhaust - Solar Wall

6 CLC A&B HVAC COST OF MONEY 3.00% GAS ENERGY ESCALATION.00% ELEC ENERGY ESCALATION 2.00% MAINTENANCE COST ESCALATION 4.00% TAX RATE 22.00% RISK FACTOR.00 PRE-TAX CASH FLOWS ALTERNATE A- DUAL AHU YEAR end of yr CAPITAL INVESTMTS AND RESIDUAL ($2,322,500) end of yr NGAS ENERGY COST or SAVINGS ($890) ($899) ($908) ($97) ($926) ($935) ($945) ($954) ($964) ($973) end of yr ELEC ENERGY COST or SAVINGS ($257,0) ($262,252) ($267,497) ($272,847) ($278,304) ($283,870) ($289,548) ($295,339) ($30,245) ($307,270) end of yr MAINTENANCE COST or SAVINGS ($20,000) ($20,800) ($2,632) ($22,497) ($23,397) ($24,333) ($25,306) ($26,39) ($27,37) ($28,466) ALT A PRE-TAX CASH FLOW ($2,322,500) ($278,000) ($283,95) ($290,037) ($296,26) ($302,627) ($309,39) ($35,799) ($322,6) ($329,580) ($336,70) PRE-TAX NPV ($4,923,237) ALTERNATE B- VAV YEAR end of yr CAPITAL INVESTMTS AND RESIDUAL ($0,695,000) end of yr NGAS ENERGY COST or SAVINGS ($890) ($899) ($908) ($97) ($926) ($935) ($945) ($954) ($964) ($973) end of yr ELEC ENERGY COST or SAVINGS ($253,820) ($258,896) ($258,896) ($258,896) ($258,896) ($258,896) ($258,896) ($258,896) ($258,896) ($258,896) end of yr MAINTENANCE COST or SAVINGS ($30,000) ($3,200) ($32,448) ($33,746) ($35,096) ($36,500) ($37,960) ($39,478) ($4,057) ($42,699) ALT A PRE-TAX CASH FLOW ($0,695,000) ($284,70) ($290,995) ($292,252) ($293,559) ($294,98) ($296,33) ($297,80) ($299,329) ($300,97) ($302,569) PRE-TAX NPV ($4,838,256) ALTERNATE C- WATER TO AIR HEAT PUMPS YEAR end of yr CAPITAL INVESTMTS AND RESIDUAL ($2,090,000) end of yr NGAS ENERGY COST or SAVINGS ($890) ($899) ($908) ($97) ($926) ($935) ($945) ($954) ($964) ($973) end of yr ELEC ENERGY COST or SAVINGS ($243,0) ($247,972) ($247,972) ($247,972) ($247,972) ($247,972) ($247,972) ($247,972) ($247,972) ($247,972) end of yr MAINTENANCE COST or SAVINGS ($50,000) ($52,000) ($54,080) ($56,243) ($58,493) ($60,833) ($63,266) ($65,797) ($68,428) ($7,66) ALT A PRE-TAX CASH FLOW ($2,090,000) ($294,000) ($300,87) ($302,960) ($305,32) ($307,39) ($309,740) ($32,83) ($34,723) ($37,364) ($320,) PRE-TAX NPV ($4,948,60) ALTERNATE D- FAN COIL UNITS YEAR end of yr CAPITAL INVESTMTS AND RESIDUAL ($2,322,500) end of yr NGAS ENERGY COST or SAVINGS ($890) ($899) ($908) ($97) ($926) ($935) ($945) ($954) ($964) ($973) end of yr ELEC ENERGY COST or SAVINGS ($240,660) ($245,473) ($245,473) ($245,473) ($245,473) ($245,473) ($245,473) ($245,473) ($245,473) ($245,473) end of yr MAINTENANCE COST or SAVINGS ($40,000) ($4,600) ($43,264) ($44,995) ($46,794) ($48,666) ($50,63) ($52,637) ($54,743) ($56,932) ALT A PRE-TAX CASH FLOW ($2,322,500) ($28,550) ($287,972) ($289,645) ($29,385) ($293,94) ($295,075) ($297,03) ($299,065) ($30,80) ($303,379) PRE-TAX NPV ($4,825,450) ALTERNATE E- CHILLED BEAMS YEAR end of yr CAPITAL INVESTMTS AND RESIDUAL ($,60,000) end of yr NGAS ENERGY COST or SAVINGS ($890) ($899) ($908) ($97) ($926) ($935) ($945) ($954) ($964) ($973) end of yr ELEC ENERGY COST or SAVINGS ($23,560) ($236,9) ($236,9) ($236,9) ($236,9) ($236,9) ($236,9) ($236,9) ($236,9) ($236,9) end of yr MAINTENANCE COST or SAVINGS ($0,000) ($0,400) ($0,86) ($,249) ($,699) ($2,67) ($2,653) ($3,59) ($3,686) ($4,233) ALT A PRE-TAX CASH FLOW ($,60,000) ($242,450) ($247,490) ($247,95) ($248,357) ($248,86) ($249,293) ($249,789) ($250,305) ($250,84) ($25,398) PRE-TAX NPV ($4,442,27)

7 205 Q3 CLC SUSTAINABLE MASTER PLAN IMPLEMENTATION

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9 LEED 2009 for New Construction and Major Renovation CLC AB Renovation - LEED Platinum Certification SD Project Checklist February 26, Sustainable Sites Possible Points: 26 Y N? Y N? Materials and Resources, Continued Y Prereq Construction Activity Pollution Prevention 2 Credit 4 Recycled Content to 2 Credit Site Selection 2 Credit 5 Regional Materials to 2 5 Credit 2 Development Density and Community Connectivity 5 Credit 6 Rapidly Renewable Materials Credit 3 Brownfield Redevelopment Credit 7 Certified Wood 6 Credit 4. Alternative Transportation Public Transportation Access 6 Credit 4.2 Alternative Transportation Bicycle Storage and Changing Rooms 2 3 Indoor Environmental Quality Possible Points: 5 3 Credit 4.3 Alternative Transportation Low-Emitting and Fuel-Efficient Vehicles 3 2 Credit 4.4 Alternative Transportation Parking Capacity 2 Y Prereq Minimum Indoor Air Quality Performance Credit 5. Site Development Protect or Restore Habitat Y Prereq 2 Environmental Tobacco Smoke (ETS) Control Credit 5.2 Site Development Maximize Open Space Credit Outdoor Air Delivery Monitoring Credit 6. Stormwater Design Quantity Control Credit 2 Increased Ventilation Credit 6.2 Stormwater Design Quality Control Credit 3. Construction IAQ Management Plan During Construction Credit 7. Heat Island Effect Non-roof Credit 3.2 Construction IAQ Management Plan Before Occupancy Credit 7.2 Heat Island Effect Roof Credit 4. Low-Emitting Materials Adhesives and Sealants Credit 8 Light Pollution Reduction Credit 4.2 Low-Emitting Materials Paints and Coatings Credit 4.3 Low-Emitting Materials Flooring Systems 7 3 Water Efficiency Possible Points: 0 Credit 4.4 Low-Emitting Materials Composite Wood and Agrifiber Products Credit 5 Indoor Chemical and Pollutant Source Control Y Prereq Water Use Reduction 20% Reduction Credit 6. Controllability of Systems Lighting 4 Credit Water Efficient Landscaping 2 to 4 Credit 6.2 Controllability of Systems Thermal Comfort 2 Credit 2 Innovative Wastewater Technologies 2 Credit 7. Thermal Comfort Design 3 Credit 3 Water Use Reduction 2 to 4 Credit 7.2 Thermal Comfort Verification Credit 8. Daylight and Views Daylight Energy and Atmosphere Possible Points: 35 Credit 8.2 Daylight and Views Views Y Prereq Fundamental Commissioning of Building Energy Systems 6 Innovation and Design Process Possible Points: 6 Y Prereq 2 Minimum Energy Performance Y Prereq 3 Fundamental Refrigerant Management Credit. Innovation in Design: Recycled Content 30% 5 4 Credit Optimize Energy Performance to 9 Credit.2 Innovation in Design: Regional Content 40% 3 4 Credit 2 On-Site Renewable Energy to 7 Credit.3 Innovation in Design: Green Cleaning 2 Credit 3 Enhanced Commissioning 2 Credit.4 Innovation in Design: Sustainability in Education 2 Credit 4 Enhanced Refrigerant Management 2 Credit.5 Innovation in Design: TBD 3 Credit 5 Measurement and Verification 3 Credit 2 LEED Accredited Professional 2 Credit 6 Green Power 2 4 Regional Priority Credits Possible Points: Materials and Resources Possible Points: 4 Credit. Regional Priority: SSc Y Prereq Storage and Collection of Recyclables Credit.2 Regional Priority: SSc4. 3 Credit. Building Reuse Maintain Existing Walls, Floors, and Roof to 3 Credit.3 Regional Priority: SSc4.3 Credit.2 Building Reuse Maintain 50% of Interior Non-Structural Elements Credit.4 Regional Priority: SSc6.2 2 Credit 2 Construction Waste Management to 2 2 Credit 3 Materials Reuse to Total Possible Points: 0 Certified 40 to 49 points Silver 50 to 59 points Gold 60 to 79 points Platinum 80 to 0

10 A&B Remodel / HVAC Replacement Agenda Meeting 2 February 20, 204, Concept Programming. Meeting #, Confirmation of Minutes 2. Sustainability Expectations Net-Zero, Carbon Neutral, LEED 3. Existing A/B wing Energy Use 4. HVAC Concept Options 5. Evaluation of Options 6. Next Step CLC SUSTAINABLE MASTER PLAN IMPLEMENTATION

11 CLC SUSTAINABLE MASTER PLAN IMPLEMENTATION

12 College of Lake County Building A & B System Options

13 GOAL OF THIS MEETING: Select system type that best meets our goals to serve the majority of the building areas. NEXT STEPS: This will allow us to begin a more detailed study on envelope and system enhancements that will further improve efficiency of the chosen system.

14 WHAT WE HAVE HEARD FROM YOU: Systems first cost must fit within budget. Maximize LEED Points Support goal of achieving net zero by minimizing energy consumption. Minimize maintenance Minimize HVAC noise levels

15 REVIEW OF GEOTHERMAL SYSTEM OPTIONS: Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

16 EVALUATION CRITERIA Annual energy costs Estimate of LEED energy points Acoustical performance Maintenance Life Expectancy of components Initial Construction cost

17 COMPARISON OF ANNUAL ENERGY COST $260,000 $255,000 $250,000 $245,000 $240,000 $235,000 $230,000 $225,000 $220,000 $25,000 Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

18 COMPARISON OF ANNUAL ENERGY COST $600,000 $500,000 $400,000 Not fully comparable but gives order of magnitude comparison our assumptions might not match how you actually operate the facility. $300,000 $200,000 $00,000 $0 Existing ASHRAE Baseline Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

19 ESTIMATE OF LEED ENERGY POINTS Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

20 ESTIMATED ACOUSTICAL PERFORMANCE (NC) Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

21 MAINTENANCE POINT EVALUATION: point for each damper, valve, or filter 3 points for AHU filters 3 points for each motor 5 points for each compressor

22 MAINTENANCE Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

23 ESTIMATE OF PROBABLE CONSTRUCTION COST $2,500,000 $2,000,000 $,500,000 $,000,000 $0,500,000 $0,000,000 $9,500,000 Dual AHU VAV Heat Pumps Fan Coil Units Chilled Beams

24 FURTHER REFINEMENT OPTIONS: Water cooled kitchen refrigeration via geothermal water. Occupancy sensors / CO2 sensors for controlling outside air. Heat recovery on the kitchen exhaust Solar Wall for preheating outside air.