data center free cooling use of heat wheel tech
DESCRIPTION
The following presentation highlights the use of advanced heatwheel technology to support free cooling initiatives in a state of the art data center facilityTRANSCRIPT
BRUNS-PAKData Center Design/Build Solutions
June 5, 2012
Data Center CoolingThe use of “Heat Wheel” Technology
Website: www.bruns-pak.com
Data Center w/Advanced Heat Wheel Technology Deployed
In 2011, BRUNS-PAK deployed a state of the art data center for a global Fortune 100 company utilizing advanced Heat Wheel technology as a major source of „free cooling‟.
Project Details:Projected
mechanical
efficiencies
PUEm = 1.15
Greenfield site Located in Northwest US
Tier IV Data Center & Infrastructure
180,000 FT2 Bldg Phase 1/55,000 FT2 Raised Floor
4,050 kW UPS Phase 1 /10,800 kW Ultimate (2N)
10MW Generation Phase 1 /24MW Ultimate (2N)
Website: www.bruns-pak.com
Data Center w/Advanced Heat Wheel Technology Deployed
The buildings energy conservation features include:
Heat wheel technology that provides approximately 7,450 hours of free cooling and 1,280 hours of partial free cooling.
Rooftop HVAC units provide outside partial and full free cooling when outside conditions permit.
Water cooled compressorized CRAC units are equipped with free cooling coils to provide free cooling when outside conditions permit.
Lighting system controlled by either the card access system or by motion sensors.
Trees and plants indigenous to the area that eliminate the need for an irrigation system.
Website: www.bruns-pak.com
What is a “Heat Wheel”?
A “Heat Wheel” also known as a rotary air-to-air energy exchanger, or rotary enthalpy wheel is a revolving cylinder filled with an air-permeable medium usually made of a non-corrosive, aluminum, honeycomb material having a large internal surface area.
Source: ASHRAE
Website: www.bruns-pak.com
How does a “Heat Wheel” work?
Adjacent supply and exhaust airstreams each flow through half the exchanger typically in a counter-flow pattern to recover heat only (sensible) or total heat (sensible plus latent).
Source: ASHRAE
Website: www.bruns-pak.com
Traditional use of “Heat Wheels”
Used for decades in ventilation air-conditioning systems
SOURCE: Illustration courtesy of XETEX
Website: www.bruns-pak.com
Benefits of Traditional “Heat Wheels”
“Pre-warm” outside air utilizing indoor conditioned air to reduce heating energy.
“Pre-cool” outside air utilizing indoor conditioned air to reduce cooling energy.
Reducing heating and cooling energy allows the ability to increase ventilation rates and improve overall indoor air quality, if desired.
Removes outdoor airstream moisture in the summer. Note: Additional moisture removal through alternate source likely required.
Adds some moisture to outdoor airstream in the winter. Note: Additional moisture through alternate source likely required.
Website: www.bruns-pak.com
Return Air (RA)(75F DB, 63F WB)
Exhaust Air (EA)(89F DB, 73F WB)
Supply Air (SA)(81F DB, 68F WB)
Outside Air (OA)(95F DB, 78F WB)
Example of Traditional “Heat Wheel” Performance - Summer
Outside air is directly supplied into the space and is “pre-cooled” by the return air which is directly exhausted.
Enthalpy Wheel
Website: www.bruns-pak.com
Return Air (RA)(72F DB, 54F WB)
Exhaust Air (EA)(27F DB, 20F WB)
Supply Air (SA)(53F DB, 40F WB)
Outside Air (OA)(7F DB, 6F WB)
Example of Traditional “Heat Wheel” Performance - Winter
Enthalpy Wheel
Outside air is directly supplied into the space and is “pre-warmed” by the return air which is directly exhausted.
Website: www.bruns-pak.com
“Heat Wheel” Technology in Data Centers
The same principles of traditional “Heat Wheel” technology are applied, except:
Sensible only “Heat Wheel” is utilized. “Heat Wheel” is arranged with the outside and
inside airstreams separated.
Source: Illustration courtesy of Kyoto Cooling
Website: www.bruns-pak.com
Benefits of “Heat Wheel” Technology in Data Centers
More efficient means of “free cooling” than direct airside and waterside economizing.
Separated airstreams minimize contaminates and humidity exposure associated with direct outside air systems.
Minimizes make-up water consumption and water treatment associated with evaporative cooling systems.
Potential reduction in overall building footprint. Cooling demand can be supplemented with 100%
air-cooled/DX during extreme climate conditions, eliminating the need for a conventional chilled water system. Note: air-cooled/DX circuit is integral to unit.
Website: www.bruns-pak.com
Benefits of “Heat Wheel” Technology in Data Centers
ASHRAE Standards developed in conjunction with IT hardware manufacturers.
2008 Version
Low End Inlet
Temperature
64.4° F DB
High End Inlet
Temperature
80.6° F DB
Low End Moisture 41.9° F Dew Point
High End Moisture 60° RH & 59° F Dew Point
ASHRAE TC 9.9 Standard allows more hours of “free-cooling” regardless of the technology used.
Website: www.bruns-pak.com
Benefits of “Heat Wheel” Technology in Data Centers
Bin Data (8760 hrs) for New York City with a supply air temperature set point of 73F DB and a return air temperature of 95F DB:
6526 hours of 100% “free cooling”. 2198 hours of partial “free cooling” (i.e. simultaneous
“heat wheel” and supplemental mechanical cooling operation).
36 hours of 100% mechanical cooling.
Source: Data courtesy of Kyoto Cooling
Website: www.bruns-pak.com
Outside Air (OA)(68F DB, 55F WB)
Exhaust Air (EA)(88F DB, 63F WB)
Supply Air (SA)(73F DB, 59F WB)
Return Air (RA)(95F DB, 67F WB)
Example of Sensible “Heat Wheel” Performance
Sensible Wheel
73F (SA) - 68F (OA) = 5F Approach to achieve 100% “free cooling”
Outside and inside airstreams are separated. Recirculated return and supply air is “pre-cooled” or “cooled” by the outside air, then directly exhausted to atmosphere.
Website: www.bruns-pak.com
Projected Mechanical Efficiencies PUEm = Mechanical Load
IT Load
Cooling Type Hot & Dry Cold & Dry Marine Hot & Damp
Refrigeration Process
(baseline) .60 .60 .60 .60
Baseline with direct
airside economizing .22 .15 .15 .23
Baseline with water-
free cooling .23 .23 .23 .26
Heat Wheel – Single
Cell .22 .08 .10 .17
Source: Data courtesy of Uptime Institute
Website: www.bruns-pak.com
Projected Mechanical Efficiencies PUEm = Critical Load + Mechanical Load
Critical Load
Website: www.bruns-pak.com
“Heat Wheel” Technology Applied in Data Centers
Some means of “hot-aisle” containment is recommended.
Website: www.bruns-pak.com
“Heat Wheel” Technology Applied in Data Centers
900kW roof-mounted Heat Wheel unit
Website: www.bruns-pak.com
“Heat Wheel” Technology Applied in Data Centers
900kW roof-mounted Heat Wheel units
Website: www.bruns-pak.com
NICHOLAS SAPIASenior Mechanical Engineer: BRUNS-PAK
PROFESSIONAL EXPERIENCE
Mr. Sapia has twenty years of experience in data center
projects. His experience ranges from evaluation of existing
facilities through coordination of design requirements for
highly technical projects. Mr. Sapia’s vast knowledge of
mechanical concepts makes him a valuable asset in
interpreting mission critical facility needs and alternatives.
Years of Experience: 20
Areas of Specialization:
Evaluating of existing facilities
through coordination of
design requirements for
highly technical projects,
redundancy concepts
Education:
A.A.S. Mechanical
Engineering Technology
B.S. Mechanical Engineering,
Train Air Conditioning, Air
Conditioning & Air
Distribution
Professional Membership:
ASHRAE
National Fire Protection
Association