efficiency of data center cooling - bicsi.org conteg...efficiency of data center cooling comparison...
TRANSCRIPT
Efficiency of Data Center cooling
Comparison of data room layouts and cooling systems
Bohumil Cimbal Product manager for Cooling Systems in CONTEG Company
Objective
• What DC arrangement is preferred?
• What is the requested cooling capacity?
• What temperatures in DC?
• How to increase Cooling efficiency?
Basic questions between investor and cooling designer
Content
• Datacenter as a heat source
• Cooling effectiveness
• Methods to increase effectivity
• DC room layouts and cooling systems
• Case study comparison
Data center cooling
Data center cooling
Increasing effectivity
• Measure and calculate efficiency awareness is a good start
• Application of power saving components fans, compressors, pumps, EC motors, etc.
• Use of sophisticated logic control software, communication of all parts in system, free-cooling, pressure control, etc.
• Set the correct temperatures air, water, refrigerant
Data center components Power consumption
TOTAL FACILITY POWER • Power delivery components (UPS,
generators, PDUs, batteries, and distribution losses external to the IT equipment)
• Cooling system components (chillers, air conditioners, pumps, and cooling towers)
• Compute, network, and storage nodes • Other miscellaneous component loads
(lighting, cleaning...)
IT EQUIPMENT POWER • Load associated with all of the IT
equipment • Computer, storage, and network
equipment • Supplemental equipment (monitors,
and workstations/laptops) used to monitor or otherwise control the datacenter
Power usage effectiveness
Power usage
effectiveness
Power usage effectiveness
Ideal Temperature in DC
Different points of view
IT equipment Comfort x Cooling Energy Efficiency
2011 Thermal Guidelines for Data Processing Environments – Expanded Data Center Classes by Technical Committee 9.9
New ASHRAE Classes 2011
Ti = 18 – 27°C ϕ = 30 - 60%
From IT point of view
Ideal Environment in DC
Ideal Temperature for IT
Server power consumption increases at higher ambient temperatures
Ideal Temperature for IT
the colder the better...
From Energy point of view
• Higher capacity of heat exchanger
• Thermal losses to the surround of DC
• Friendly compressor circuit conditions
• Higher efficiency of cold source
• Long free-cooling utilization
Benefits of higher temperature: Air temperature
increase
AC energy savings
1 K 4 %
2 K 8 %
3 K 12 %
4 K 16 %
5 K 20 % Source: Schweizer Bundesanstalt für Energiewirtschaft
Ideal Temperature in DC
Ideal Temperature in DC
Temperature impact on Cooling capacity (kW)
Return air Temperature
Water temperature
6/12 °C 10/16 °C 12/18 °C 15/21 °C
45 °C 81,8 72,4 67,7 60,7
40 °C 70,1 60,7 55,9 48,9
35 °C 58,3 48,9 44,2 37,1
30 °C 46,5 37,1 32,4 25,3
25 °C 37,1 27,7 23,0 15,9
Ti = 25°C Ti = 18°C
22% annual energy consumption difference
Ideal Temperature in DC
Hot and Cold Air Separation
Right conditions for computers + Maximal energy efficiency
Blanking panels and Separation frames
BLANKING PLATES
SIDE VIEW
Racks in open aisle
Not enough air
Too much air
Impossible to keep steady Servers change the air-flow continually
Optimal air flow
Mechanical Air Separation
The only possibility !
with air flow control
Plenum Feed With Room Return
Modular Closed Loop w. In-row Units
Cold aisle Containment w. Top cooling
Room Feed with Plenum Return
Cold aisle Containment w. Plenum Feed or In-row
Closed aisle Containment w. In-row Units
Data Center Room Arrangements
Data room Cooling systems
Comparison CRAC x In-Row x Topcooling
DC arrangement
Cold and Hot Aisles
CRAC = Computer Room Air Conditioner
Air path length
CRAC solution
• Cold air delivered under floor • Long way to servers
In-Row Air-conditioning units integrated into rows of racks
Air path length
In-ROW solution • Deliver cold air where required –
front of servers
Top cooling Air-conditioning units on top of racks
Air path length Topcooling solution • Deliver cold air where required –
front of servers
Temperature zones
In-ROW solution • Easy to plan different power and
temperature zones
CRAC solution • Only one temperature in all zones
in one room
Easy future enlargement In-ROW solution • Possibility of DC enlarging in steps
- minimizing initial investment
CRAC solution • Big initial investment • Low initial efficiency
Basic features comparison
CRAC In-row Top
cooling
Short air path to servers Easy to plan different power and temperature zones DC enlarging in steps - minimizing initial investment Open or Closed Architecture Cold or Hot Containments Technical service out of DC room Water in DC room Total power consumption of indoor units
Financial effect:
1. Floor area savings 2. Energy savings
- 16 racks 600mm, depth 1000mm, height 42U - contained cold aisle - 35°C in hot zone, 25°C in cold zone - Chilled water system (10/15°C) - heat load 6kW/rack (total demanded cooling capacity 96 kW) - requested redundancy n+1
Example:
Case study
• 3 CRAC units • cooling capacity 53 kW • air flow 9.000 m3/h • dimensions 950 x 900 mm • consumption 1,8 kW
• Occupied floor area = 2,6 m2
• Total consumption 3,6 kW (2 running units)
CRAC (CW)
• 6 in-row units • cooling capacity 21 kW • air flow 3800 m3/h • dimensions 300 x 100 mm • consumption 0,77 kW max
(0,3 kW at capacity 96/6=16 kW per unit)
• Occupied floor area = 1,8 m2
• Total consumption 1,8 kW (6 low-speed running units)
In-Row (CW)
• 4 Topcooling units • cooling capacity 38 kW • air flow 7.700 m3/h) • dimensions 2400 x 600 mm • consumption 0,7 kW max
(0,2 kW at capacity96/4=24 kW per unit)
• Occupied floor area = 0 m2
• Total consumption 0,8 kW (4 running units)
CoolTop (CW)
Case study
• 3 CRAC units • cooling capacity 53 kW • air flow 9.000 m3/h • dimensions 950 x 900 mm • consumption 1,8 kW
• Occupied floor area = 2,6 m2
• Total consumption 3,6 kW (2 running units)
CRAC (CW)
• 6 in-row units • cooling capacity 21 kW • air flow 3800 m3/h • dimensions 300 x 100 mm • consumption 0,77 kW max
(0,3 kW at capacity 96/6=16 kW per unit)
• Occupied floor area = 1,8 m2
• Total consumption 1,8 kW (6 low-speed running units)
In-Row (CW)
• 4 Topcooling units • cooling capacity 38 kW • air flow 7.700 m3/h) • dimensions 2400 x 600 mm • consumption 0,7 kW max
(0,2 kW at capacity96/4=24 kW per unit)
• Occupied floor area = 0 m2
• Total consumption 0,8 kW (4 running units)
CoolTop (CW)
Case study
Financial effects:
1. Floor area savings
Floor area per unit Number of units
Occupied floor area Floor area price Financial loss
(m2) (pcs) (m2) (€/m2/year) (€/year)
Top cooling 0 4 0 10 000 0
In-Row 0,3 6 1,8 10 000 18 000
CRAC 0,9 3 2,7 10 000 27 000
Expected price of one footprint (0,6m2) is 500€ per month.
Case study
Financial effects :
1. Energy savings Indoor units
consumption Number of
units Annual power consumption
Energy price Annual costs
(kW) (pcs) (kWh) (€/kWh) (€/year)
Top cooling 0,2 x 4 = 0,8 4 7008 0,15 1 051
In-Row 0,3 x 6 = 1,8 6 15768 0,15 2 365
CRAC CW* 0,7 x 3 = 2,1 3 18396 0,15 2 759
CRAC CW** 1,8 x 2 = 3,6 3 31536 0,15 4 730
* Redundant units are working (partial operation). ** Redundant units are stand-by.
Case study
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Top cooling In-Row CRAC
Annual savings (€)
Summary
• DC concept Business plan in time, sizes, capacities
• Cooling design cooling system, CFD simulation, critical situations, TIER classes, safety points
• Building process product quality, piping system, monitoring
• Operation air separation, temperature setting, efficiency tracing