ashrae 2006 - bvnhs
DESCRIPTION
ASHRAE TEGA Honorable Mention award winnerTRANSCRIPT
James E. Megerson, PEVice PresidentASHRAE Member
Blue Valley NorthHigh SchoolOverland Park, Kansas
ASHRAE Technical Energy and Governmental Affairs
2005 Honorable Mention – Existing Institutional
Displacement Ventilation
Original school Built in 1986
270,000 sq. ft.
Student enrollment
1605 in 2004-2005 school year
Displacement Ventilation
Displacement Ventilation
1986 Design 14 - DX VAV Rooftop units w/ hot water heat
- 7 Constant Volume
- 7 Variable Air Volume
- Discharge air Damper
Single duct VAV air distribution
97 Fan-Powered Series – VAV Boxes w/ HW reheat
Displacement Ventilation
Pneumatic controls – Later revised to Legacy DDC
Water Tube Boilers (Oversized heat exchangers)
Reverse return HW distribution
Constant Volume pumping
Ventilation design for 5 CFM / student
T12 lights with magnetic ballast
Problems IAQ Complaints from Students and Teachers
Multiple studies by EPA & Industrial Hygienist
CO2 levels in excess of 3000ppm common
20% of VAV boxes not operating
All VAV boxes programmed for intermittent occupancy
Displacement Ventilation
Concerns Bring Building to current ASHRAE 62 standards
Requires adding 26,000 cfm OA– double original design
Reduce or minimize impact on energy usage
Add 95 tons of cooling to building for increased OA
Humidity in space from decreased sensible load
Displacement Ventilation
Solutions Devise a plan to solve all
the problems
Balance the energy increase by upgrading lighting
Displacement Ventilation Air Distribution
Provide heat in RTU
Additional heating at space
Displacement Ventilation
Displacement Ventilation
Displacement Ventilation
Displacement Ventilation
Displacement Ventilation
Making 65 Degree Air
Displacement Ventilation
26904483Occupants
5121024Electric Equipment
934215509Total Space Sensible Load:
4501349Roof Transmission
18023153Lighting
4201120Wall Transmission
DisplacementConventional
3911302Window Transmission
30783078Window Solar
Space Sensible Load (Qs)Space Loads
0.9
718
55
75
CFM/SF=
Supply CFM=Qs/(1.08*(75-55))=
Supply Air Temperature (ºF)=
Space Temperature Setpoint (ºF)=
0.9
721
63
75
Typical Classroom Load Profile
Displacement Ventilation
Annual Weather Data(US Air Force Weather Manual - 9:00a.m. to 5:00p.m.)
CITY 55F & Below 55-65F
7 days Mon-Fri 7 days Mon-Fri
Albany, NY 1470 1050 413 295
NYC – Islip 1797 1283 490 350
Chicago, Ill 1414 1010 384 416
Albuquerque 1001 715 442 315
Phoenix 204 145 452 322
San Francisco 1170 835 1335 953
Kansas City 1198 855 428 305
Denver 1280 914 716 511
Seattle 1321 943 800 571
Displacement Ventilation
IAQ Typical Example
Displacement Ventilation
IAQ Typical Example
Displacement Ventilation
16% Gas Consumption
9% Electrical Consumption
Utility Savings
Displacement Ventilation
Two phases
2002 summer
2004 summer
Phase I - $2,285,000
Phase II - $1,115,000
Cost of Upgrade
Displacement Ventilation
Typical Airflow
0.9 cfm / sq. ft.
1.1 – 1.2 cfm / sq. ft.
Sheet metal
.46 lbs - .61lbs/ sq. ft.
.8 - .9 lbs / sq. ft.
Interesting Data
Displacement Ventilation
Other Sustainable Features Pulse Combustion Boilers
Boiler Management System Lonworks BAS
Web Enabled GUI
Variable Speed Pumping CO2 Monitoring Ventilation air monitoring
Indirect Lighting with T8 fixtures
Occupancy sensor lighting control
Displacement Ventilation