Using ASHRAE s Books to Save Energy. Presented by Don Beaty President DLB Associates ASHRAE Technical Committee TC 9.9

Transcription

1 Using ASHRAE s Books to Save Energy Presented by Don Beaty President DLB Associates ASHRAE Technical Committee TC 9.9 1

2 Agenda Opening Comments Part 1 Introduction Part 2 TIPS 1 to 8 Closing Comments 2

3 Opening Comments For Mission Critical Facilities, MISSION comes first so ENERGY must fit in. What RISKS are associated with saving energy in data centers? How to save energy in BOTH new and existing facilities. How important is it for Facilities to understand some about IT? Effects of High Density, Virtualization, & Cloud Computing. How much potential is there to reduce data center energy? How ASHRAE can help. 3

4 Part 1 Introduction ASHRAE & Technical Committee TC 9.9 TC 9.9 Datacom Book Series SHOW & TELL Interdependence of Facilities & IT IT Overview IT Energy Usage In Servers IT Virtualization: Facilitates Hardware Consolidation Part 1 Closing Comments 4

5 ASHRAE Overview 1. ASHRAE (American Society of Heating Refrigerating, & Air-Conditioning Engineers) is a technical society specializing in cooling, formed in ASHRAE has over members & has members in 135 countries. 3. ASHRAE focuses on maintaining an unbiased role within the industry. 4. ASHRAE actively writes standards, guidelines, model codes, etc. Ice Cooled System (Circa 1890) General Electric Room Cooler (Circa 1932) Computer Room Air Conditioner (Circa 1970) 5

6 Vendor Biased vs. Vendor Neutral Vendor Specific Bottled Water (generic) Tap Water (generic) 6

7 ASHRAE Technical Committee TC 9.9 Overview Title: Mission Critical Facilities, Technology Spaces & Electronic Equipment Objective: To be recognized by ALL areas of the datacom industry as the UNBIASED engineering leader in HVAC & an effective provider of technical datacom information. Scope: All datacom facilities: datacom stands for data processing & communication facilities. It includes rooms or closets used for communication, computers, or electronic equipment. 7

8 TC 9.9 Over 200 members & participants Over 50 international members Members in 12 countries including the Americas, Europe, & Asia Good cross section of members; focused on a mixture of: 1) Datacom Producers (vendors of IT products, cooling products, etc.) 2) Datacom Users (IT departments, Facilities departments, etc.) 3) Datacom General (consultants, academia, agencies, utility companies) Vendor neutral, unbiased, provide choices 8

9 TC 9.9 Datacom Book Series 1. Thermal Guidelines for Data Processing Environments (2004, 2008) 2. Datacom Equipment Power Trends & Cooling Applications (2005) 3. Design Considerations for Datacom Equipment Centers (2006, 2008) 4. Liquid Cooling Guidelines for Datacom Equipment Centers (2006) 5. Structural & Vibration Guidelines for Datacom Equipment Centers (2008) 6. Best Practices for Datacom Facility Energy Efficiency (2008) 7. High Density Data Centers Case Studies & Best Practices (2008) 8. Particulate & Gaseous Contamination in Datacom Environments (2009) 9. Real-Time Energy Consumption Measurements in Data Centers (2009) 9

10 SHOW & TELL Right Sizing Buckets filled too slowly, too fast, just right CPU Capacity Explosion # of transistors / CPU multiplying by 25 times in 10 years CPU Heat Need for uninterruptable cooling supply Rack Heat 1 rack can equal 1 or more fireplaces Clothes Iron Capacity of liquid to cool versus air Examples of High Density Installation Shrinking Data Center Where will the cooling air come from? Get Smart! Do not operate in a cone of silence! 10

11 Interdependence of Facilities & IT IT Facilities We can NO LONGER afford the barrier between Facilities and IT Think more broadly; think HOLISTIC tradeoffs. 11

12 IT Overview Applications (software) computer programs such as databases, , simulation; in addition to software there are operating systems. Hardware compute servers, storage servers, tape drives Servers, HPC, Main Frames Components processors, memory, I/O, video Storage solid state, disk drives, tape drives Systems or Networks WAN, MAN, LAN, and virtualization Applications Hardware Systems / Networks 12

13 IT Energy Usage In Servers 13

14 IT Virtualization: Facilitates Hardware Consolidation 10 servers CPU Load 90% 5% 5% 1 server Consolidation can be 10:1, running the same # of applications on fewer servers 14

15 Part 1 Closing Comments Video 1) # of transistors increase by a factor of 25 in 10 years; how do you plan an infrastructure for such a growth? 2) A rack can produce INTENSE heat; liquid cooling is a VERY efficient solution IT Loads 1) IT is a moving target; facilities MUST maintain an understanding of IT otherwise they RISK being blindsided with demands they cannot meet. 2) IT loads are multivariable resulting in a need to understand some about both the hardware (network, processing, storage) and software (applications) 15

16 Part 2 Tips 1 to 8 TIP 1 Approach everything holistically; optimizing the tradeoffs (e.g. Facilities vs. IT) TIP 2 Use ASHRAE Recommended Environmental Specifications TIP 3 Use Actual Loads rather than Nameplate Ratings TIP 4 Use economizers (free cooling) to the maximum extent possible TIP 5 Treat power, cooling & networking as services TIP 6 Air Management TIP 7 Right size all aspects of the power, cooling, and networking services TIP 8 Focus on performance 16

17 TIP 1 Approach Everything Holistically; Optimizing the Tradeoffs (e.g. Facilities vs. IT) 17

18 TIP 1 The Holistic Approach Industry Boundaries INTERFACE POINT INTERFACE POINT IT Industry Facilities Industry Utilities Chip / CPU / Board Server / Packaging Rack / Cabinet Row / Server Floor Central Plant / Equipment Yard Utility Plant / Substation 18

19 TIP 1 The Holistic Approach Introduction IT <> Design & Construction <> Facilities & Operations Industries have independent targets, different emphases, and must be considered holistically. A successful data center project benefits from the SEAMLESS integration of many traditionally isolated industries. Tradeoff Cost (CapEx, OpEx) Schedule (speed to market / speed to deployment) Reliability / Availability Future Flexibility (avoid premature obsolescence) Energy Efficiency IT vs. Facilities Discipline Importance Low Medium High 19

20 TIP 1 The Holistic Approach A Moving Target Data centers are basically commercial buildings that house IT equipment (computers). Commercial buildings power & cooling infrastructure are typically built to last 15 to 25 years versus only 3 to 5 years for IT equipment. So, data centers must be able to support MULTIPLE GENERATIONS of IT equipment. Future IT equipment power density is challenged by conflicting trends: 1) Continued Compaction (speed, capacity, compute focus) 2) Reduced Compaction (larger but more efficient equipment) Holistic Capacity Planning (Servers, Network, Power, Cooling, Space) Major Steps 1) Clearly define Service Level Agreements (SLAs) 2) Analyze current capacity 3) Predict future capacity 20

21 TIP 1 Capacity Planning for the Future Topic Projected Growth Day 1 Need (kw) Additional Needs After IT Refresh (kw) First Second Third Fourth SLA Client 1 Significant SLA Client 2 None Storage Significant Network Decline SLA Service Level Agreement Client can be internal or external 21

22 TIP 1 Partitioning Into Zones Dividing one server area into many zones facilitates the planning and / or implementation of various cooling strategies. Topic Zone 1 Zone 2 Zone 3 Localized Cooling None Rear-door In-Row Cooling Source Air Air & Liquid Liquid IT Airflow Configuration F-R F-R F-T Air Distribution VUF VUF VOH Cold Aisle Containment No No Yes Redundancy No Yes Yes 22

23 TIP 2 Use ASHRAE Recommended Environmental Specifications 23

24 TIP 2 Introduction Prior to ASHRAE s Thermal Guidelines for Data Processing Environments, NO published multi-vendor or vendor neutral temperature & humidity guidelines existed. ASHRAE s Thermal Guidelines are supported by ALL the major IT equipment manufacturers. Compounded, perceived SAFETY factors resulted in data centers commonly operating MUCH cooler than necessary; often less than 20 C (68 F). First published in 2004, in 2008 ranges were expanded to create MORE opportunities for energy saving & economizers. ASHRAE s Thermal Guidelines have a RECOMMENDED Temperature Range a statement of reliability saying that operating ANYWHERE within 18 C to 27 C (64,4 F to 80,6 F) is safe for data centers. 24

25 TIP 2 IT Equipment Environment Specifications Class Dry Bulb Temperature C % Relative Humidity Allowable Recommended Allowable Recommended Max. Dew Point C Max Rate of Change C / hr 1 15 to to to to to to 80 5,5 C DP to 60% RH and 15 C DP 5,5 C DP to 60% RH and 15 C DP 17 5 / 20* 21 5 / 20* 3 5 to 35 N/A 8 to 80 N/A 28 N/A 4 5 to 40 N/A 8 to 80 N/A 28 N/A * 5 C for data centers employing tape drives, 20 C for data centers employing disk drives. Product Powered ON (Operational) Specifications Environment Specifications based on a max. elevation of m 25

26 TIP 3 Use Actual Loads Rather than Nameplate Ratings 26

27 TIP 3 Main Message to Facilities Stakeholders Previous experience with utilization rates or demand factors on IT equipment is NO longer valid (e.g., 25% of the nameplate data). Design of today s IT equipment combined with RADICAL changes in software are DOUBLING or TRIPLING the IT equipment demand / utilization. Very, very possible to experience demands of 50% to 75%. This is NOT a theoretical change but rather a MAJOR paradigm shift. Demand Demand Previous Experience Virtualization / Technology 27

28 TIP 3 Nameplate Data vs. ASHRAE Equipment Thermal Report Datacom equipment manufacturers NAMEPLATE data has a REGULATORY safety focus & the values are NOT an accurate reflection of heat rejection. ASHRAE s Thermal Guidelines require manufacturers to publish: 1) Steady state heat release numbers in watts. 2) Maximum & nominal airflow quantity & pattern under Normal operating conditions. 3) Variations of above for specific equipment configurations via predictive algorithms. This report is similar to the new US EPA Energy Star Program s required report. 28

29 TIP 3 Actual Load (ASHRAE Thermal Report) IBM Server Model Rack Mounted Drawer Configuration Condition Typical Heat Release (Votage 110 V) Airflow Nominal a Maximum at 35 C Weight Overall System Dimensions b (W x D x H) watts cfm (m 3 /h) cfm (m 3 /h) lbs kg in. mm Minimum x 37 x x 933 x 584 Full x 37 x x 933 x 584 Typical x 37 x x 933 x 584 ASHRAE Class Configuration 3 Description Model Minimum Full Typical 1-way, 1.5 GHz processor, 16 GB memory 2-way, 1.65 GHz processor, maximum memory 1-way, 1.65 GHz processor, 16 GB memory a. The airflow values are for an air density of 1.2 kg/m 3 (0.075 lb/ft 3 ). This corresponds to air at 20 C (68 F), kpa (14.7 psia), & 50% relative humidity. b. Footprint does not include service clearance or cable management, which is zero on the sides, 46 in. (1168 mm) in front, & 40 in. (1016 mm) in the rear. 2004, ASHRAE Thermal Guidelines For Data Processing Environments adapted by DLB Associates, Consulting Engineers, P.C. 29

30 TIP 3 Actual Load (ASHRAE Thermal Report) IBM Server Model Rack Mounted Drawer Configuration Condition Typical Heat Release (Votage 110 V) Airflow Nominal a Thermal Report Minimum = 420 watts Weight Overall System Dimensions Thermal Report Maximum = 600 b (W watts x D x H) Maximum at 35 C Nameplate = 920 watts watts cfm (m 3 /h) cfm (m 3 /h) lbs kg in. mm Minimum x 37 x x 933 x 584 Full x 37 x x 933 x 584 Typical x 37 x x 933 x 584 Nameplate Data for IBM 520 Server: ASHRAE Class Minimum / Nameplate = 420 / 920 = 46% Configuration 3 Description Model Maximum / Nameplate = 600 / 920 = 65% Minimum 1-way, 1.5 GHz processor, 16 GB memory Nameplate 920 W (1 kva w/ PF = 0.92) Full 2-way, 1.65 GHz processor, maximum memory 1-way, 1.65 GHz processor, Maximum Typical / Minimum = 600 / 420 = 143% 16 GB memory a. The ASHRAE airflow thermal values are report for an air 420 density to 600 of W1.2 kg/m 3 (0.075 lb/ft 3 ). This corresponds to air at 20 C (68 F), kpa (14.7 psia), & 50% relative humidity. b. Footprint does not include service clearance or cable management, which is zero on the sides, 46 in. (1168 mm) in front, & 40 in. (1016 mm) in the rear. 2004, ASHRAE Thermal Guidelines For Data Processing Environments adapted by DLB Associates, Consulting Engineers, P.C. 30

31 TIP 4 Use Economizers (Free Cooling) to the Maximum Extent Possible 31

32 TIP 4 Potential Cooling Savings using an Economizer Average Data Center Power Allocation Other (11%) Avg. Power for Cooling HVAC Cooling 23% HVAC Fans 8% HVAC Cooling (23%) TOTAL 31% Using 100% Economizer Energy Savings = 23 / 31 HVAC Fans (8%) Lighting (4%) UPS (8%) IT Equipment (46%) = 74% ASHRAE Book Figure 1.4 Average Power Allocation for 12 Benchmarked Data Centers (source: LBNL 2007a) 32

33 TIP 4 Raise your Data Center Temperatures up to 27 C Operational Temperatures in Data Centers have RADICALLY CHANGED. There is ABSOLUTELY NO reason to operate at 20 C to 21 C Operate data centers at temperatures of 24 C to 27 C to SAVE energy without impacting performance You are NOT at risk; industry recognized ASHRAE environmental specifications provide a quotable source. 33

34 TIP 4 Oversimplified Air-Side Economizer Overhead Air Supply Raised Floor Air Supply 34

35 TIP 4 Air-Side Economizer Exhaust Air 2 Intake Air 1 Return Air 3 4 Location Economizer None Full Partial Winter 1 Intake Airflow 0 % 100 % 100 % 10 % 2 Exhaust / Relief Airflow 0 % 100 % 100 % 10 % 3 Return Airflow 100 % 0 % 0 % 90 % 4 Cooling Coil Load 100 % 0 % 50 % 0 % 35

36 TIP 4 Water-Side Economizers Water-Side Economizer Operation Scheme Mode Condenser Water Temp. Water Chiller Heat Exchanger Normal Above Cooling Coil Design On Bypassed Partial Indirect Economizer Below Cooling Coil Design Part Load Pre-Cooling Full Indirect Economizer Below Cooling Coil Design Off On ASHRAE Book Figure 4.7 Indirect Water-Side Economizer 36

37 Bogotá Weather Data Cooling DB / MCWB, C Evaporation WB / MCDB, C Heat / Cool Degree-Days C-day 0,4% 1% 2% 0,4% 1% HDD / CDD 18,3 21,2 / 13,6 20,8 / 13,5 20,1 / 13,4 15,4 / 19,0 15,0 / 18, DB: Dry Bulb Temperature MCWB: Mean-Coincident Wet Bulb Temperature WB: Wet Bulb Temperature MCDB: Mean-Coincident Dry Bulb Temperature HDD and CDD 18,3: Annual Heating and Cooling Degree-Days, Base 18,3 C Day 1 Degree-Day = 1 degree difference between base and 1 day s average temperature 37

38 Dirt Smoke Products of Combustion 38 Pollen

39 TIP 5 Treat Power, Cooling & Networking as Services 39

40 TIP 5 Service Level Agreements (SLA) Definition An SLA is a single document for ALL stakeholders describing the level of service expected by a customer from a supplier (can be the Facilities dept). Increases UNDERSTANDING, AWARENESS and RESULTS SLAs lay out the metrics used to measure the service and the remedies or penalties if the agreed-upon levels are NOT achieved. Define power, cooling, and networking as services. Then define them NOT at a facility level but at a Zone or Cluster level. Include: 1) Level of uptime 2) Load profile (magnitude, degree of variability) 3) Quality of service (e.g., voltage or temperature variation tolerance) 4) Tolerance for downtime during major refreshes (e.g., minutes, hours, days, weeks) 40

41 TIP 5 Service Level Agreements Cooling Service Level Agreement (SLA) DESCRIPTION MINIMUM MAXIMUM Dry Bulb Temperature 18 C 27 C Rate of Temperature Rise / Hour N / A 5 C Relative Humidity N / A 60% Dew Point 5,5 C 15 C Gaseous Contamination (copper & silver) N / A 300 Å / month Air Quality MERV 8 N / A Conditions: 1. Approval of Adds, Moves & Changes for Hardware, Software, etc. 2. Conditions at Equipment Inlet 3. Approval for removing floor tiles for any reason MERV Minimum Efficiency Reporting Values (ASHRAE Standard 52) 41

42 Tip 6 Air Management 42

43 TIP 6 Airflow Optimization Challenges Bypass Air / Short-Circuiting Recirculation Leakage This scenario wastes cooling capacity This scenario increases the inlet temperature to the equipment 43

44 TIP 6 Airflow Optimization Solutions Blanking Panels Cable Penetration Seals 44

45 TIP 6 Airflow Optimization Mal-Distributed Air Mal-distributed air does not reach the intended location and is caused by: 1) Leakage through air ducts / raised flooring (e.g., between floor tiles) 2) Unsealed raised floor cutouts such as cable openings 3) Incorrectly located air outlets / perforated floor tiles Air outlets should ONLY be in cold aisles near active IT equipment Varying Scenarios of % of Unintended Destination Scenario % of Air Distribution Intended Destination Unintended Destination % 0 % 2 75 % 25 % 3 50 % 50 % 45

46 TIP 7 Right Size All Aspects of the Power, Cooling, and Networking Services 46

47 TIP 7 Data Center Design Right Sizing In Variable Conditions What is the right size for a data center and its systems? Many things that impact the load of a Data Center including: 1) Reliability Redundant Components, Concurrently Maintained, Fault Tolerant 2) Variable Occupancy In the Rack, in the Row, on the Floor Specific Hardware Configuration (CPU, RAM, Hard Drive, etc.) 3) Variable Utilization Idle vs. Fully Utilized Software / Application Hardware Virtualization Network Configuration 47

48 TIP 7 Right Size Each Cooling Component for Improved Efficiency of the Cooling System The cooling equipment within a data center is often at partial load and operates 24 / 7; consequently selecting efficient equipment is critical. Typical Cooling System There are energy saving opportunities in each piece to the Cooling System 48

49 TIP 7 Data Center Design Right Timing When do you provision for and implement an increase in data center load? 49

50 TIP 7 Data Center Design Modular Overview Utilizing modular systems can help capacity planning by increasing system flexibility. Consider Day 1 initial deployment needs vs. ultimate deployment will cooling needs increase slowly or rapidly? Modular cooling solutions can be implemented in phases: 1) Day 1 install can be faster than construction of a full central plant 2) Eliminate unused equipment 3) Expand cooling capacity as needed to support IT 4) Delay capital expenditures until additional capacity is needed 50

51 TIP 8 Focus On Performance 51

52 TIP 8 Focus on Performance PUE and DCiE Metrics facilitate quantification of effectiveness and efficiency of data centers. Power Usage Effectiveness (PUE) = Data Center Infrastructure Efficiency (DCiE) = Total Facility Power IT Equipment Power IT Equipment Power Total Facility Power 1/PUE = DCiE Power Storage Utilization Server Utilization Area Cooling Theoretical Target Peak Average Network Utilization Source: The Green Grid DC Utilization Weight Airflow Green Grid Productivity Indicator 52

53 TIP 8 Focus on Performance Understanding the Power Impact The single largest component of energy usage in data centers is that used by the IT equipment itself. The critical IT Interface is the Service Entrance. Other (11%) IT Equipment (46%) Everything Else (50%) IT (50%) HVAC Cooling (23%) HVAC Fans (8%) Lighting (4%) UPS (8%) Source: LBNL PUE = 2.0 Typical Data Center Power Allocation 53

54 Closing Comments Economizers can save considerable energy; ASHRAE standards are helping to increase the opportunity for free cooling hours per year. Each application has its own set of unique conditions that create the optimum opportunity for performance improvements. A HOLISTIC approaches provides the MOST opportunity for optimization; requires the SEAMLESS INTEGRATION of many traditionally ISOLATED industries. Data Center designs require much more FUTURE-PROOFING than other facilities to support MULTIPLE GENERATIONS of IT equipment. Data Centers focus on MISSION CRITICAL RELIABILITY through the use of redundant components is in CONFLICT with energy efficiency. 54

55 Purchasing the Books ASHRAE Datacom Series Books ASHRAE Member Thermal Guidelines Datacom Equip. Trends Design Considerations Liquid Cooling Yes $46 $46 $46 $46 No $54 $54 $54 $54 Quantity Discounts Available ******* Books available in Paperback & PDF Formats Purchasing the Books 55

56 Purchasing the Books ASHRAE Datacom Series Books ASHRAE Member Structural & Vibrations Best Practices High Density Contamination Measurements Yes $46 $46 $46 $46 $46 No $54 $54 $54 $54 $54 Quantity Discounts Available ******* Books available in Paperback & PDF Formats Purchasing the Books 56

57 Contact Information Don Beaty DLB Associates Tel: ASHRAE TC 9.9 Website 57

58 PART 1 Supplemental Material (not presented) 58

59 Overall Data Center Productivity Metrics 1) Plot utilization on a radial graph 2) A visual assessment of how resources are being used PUE Power Utilization Effectiveness DCiE Data Center Infrastructure Efficiency Source: The Green Grid 59

60 Green Grid Productivity Indicator 1) Often, tradeoffs must be made in certain categories to achieve improvement in others. Source: The Green Grid 60

61 Applications (software) Metrics You may find that software upgrades cause your hardware to be over- or under-utilized (NOT physical yet impacts power, cooling, and networking services). Application IT Provisioning Actual Utilization Base Upgrade 1 Upgrade 2 A 10kW 80% 75% 50% B 50kW 80% 95% 110% C 150kW 80% 72% 80% 61

62 PART 2 Supplemental Material (not presented) 62

63 TIP 2 Recommended vs. Allowable Specification Envelopes Recommended The purpose of the recommended envelope is to give guidance to data center operators on maintaining HIGH reliability and also operating their data centers in the most energy efficient manner. Allowable The allowable envelope is where the IT manufacturers test their equipment in order to verify that the equipment will function within those environmental boundaries. Prolonged Exposure Prolonged exposure of operating equipment to conditions outside its recommended range, especially approaching the extremes of the allowable operating environment, CAN result in decreased equipment reliability and longevity. Occasional, short term excursions into the allowable envelope MAY be acceptable. OPERATING AT COLDER TEMPERATURES WASTES ENERGY NEEDLESSLY! 63

64 TIP Temperature Recommendation Changes (Dry Bulb) Low Limit 1) Lower limit from 20 C to 18 C (68 F to 64,4 F) 2) Increase potential economizer hours 3) No concern over lowering temperature 4) Might increase operating costs for non-economizer systems / hours High Limit 1) Increase limit from 25 C to 27 C (77 F to 80,6 F) 2) Increase potential economizer hours 3) Could minimally increase energy usage at servers increased fan speeds 4) Potential energy savings for non-economizer systems 64

65 TIP Moisture Recommendation Changes Low Limit 1) Greater number of hours without humidification 2) Changed from 40% RELATIVE humidity to 5,5 C (42 F) Dew Point (absolute humidity) 3) Requires additional research to understand ESD / humidity relationship to lower limit further High Limit 1) Changed from 55% RH to 60% RH and 15 C (59 F) Dew Point 2) Requires additional research to understand contaminant/humidity relationship at high humidities 3) Increased moisture can result in latent cooling if a cold coil is used for cooling. Capacity that is normally used for sensible cooling is now used to remove moisture from the air. 65

66 TIP 2 Noise & Energy 1) Some server mounted cooling fans vary their speed to stabilize the chassis temperature. As the inlet air temperature to the server increases, so does the speed of the cooling fan(s). This increased fan speed increases: 2) The energy used at the server level (the energy consumed by the fan increases with the cube of its rotational speed.) 3) The noise emitted from the cooling fans (a 20% increase in fan speed will produce a 4 db increase in noise level.) 4) Even though fan power consumption might increase minimally if warmer temperatures (above 25 C) are maintained in the space, the overall energy consumption of the facility would be reduced. 5) Sound levels in excess of 85 db(a) require adherence to OSHA regulations. 66

67 TIP 2 Contamination Two kinds of contamination: 1) Particulate Matter (PM) 2) Gaseous Sources of contamination 1) Outdoor air Infiltration and ventilation systems 2) Indoor AHUs, copiers, people, construction, normal operations, raised floors, and humidification systems 67

68 TIP 2 Particulate Matter (PM) Contamination PM has the potential to cause significant problems which often can be addressed with filtration. Some types of PM are: 1) Abrasive or corrosive 2) Electrically / thermally conductive (zinc & tin whiskers) 3) Electrically / thermally insulating 4) Hydroscopic absorb moisture & become conductive 5) Activators of smoke detectors and fire suppression systems Potential areas of PM accumulation include small airflow openings; heat sinks; sharp, rough or abrasive surfaces; areas with sudden reduction in air speed or change in direction. 68

69 TIP 2 Gaseous Contamination Gaseous contamination is seldom an issue but when it is, it can be significant. The most common types of gaseous contamination are: 1) Sulphur dioxide product of combustion of fossil fuels 2) Ozone found in smog 3) Hydrogen Sulfide More study is needed to determine the affect of these, and other gaseous contaminants, on IT equipment. 69

70 TIP 4 Barriers to the use of air economizers 1) Concern over increased PM requires properly designed, installed & maintained filtration system (s) 2) Concern over INCREASED gaseous contamination more research is needed 3) Concern over LOSS of humidity control can require large amounts of humidification / latent cooling 4) Concern over LOSS of temperature control 5) Any air that enters the space should be conditioned & filtered to ensure the temperature, humidity & cleanliness remain within ASHRAE s guidelines. 6) These concerns can be addressed through good engineering, control, commissioning, operation and maintenance practices. 70

71 TIP 7 Future Load (Trend Chart in KW / Rack) (Rack = 7 s.f. / 0,74 s.m.) For 7 s.f (0,65 s.m.) per rack, the trend chart indicates about 30 kw / Rack for Say your current operating racks (or racks scheduled to be purchased) are 15 kw / Rack. The adjustment factor that should be applied = 15 / 30 = 0,5 Using the chart & adjustment factor of 0,5 : 30 kw / rack KW / Rack KW / Rack KW / Rack KW / Rack 71

72 TIP 7 Cooling Equipment Fans HVAC fans account for 8% of total datacenter power consumption. Energy saving opportunities include: REDUCED system pressure drop 1) Minimize supply and return air distribution system pressure drop. 2) Use low pressure drop filters & conduct frequent filter maintenance REDUCED air volume required for cooling by 1) Implementing variable flow / variable speed fans 2) Maximize cooling coil temperature change IMPROVED equipment efficiency 1) Select fans with a high efficiency at expected operating conditions 2) Use premium-efficiency or electrically-commutated motors 72

73 TIP 7 Cooling Equipment Fan Curve Point Static Pressure Air Flow 1 2,55 cm m³/hr 2 1,50 cm m³/hr 3 1,05 cm m³/hr Point Speed Air Flow RPM m³/hr RPM m³/hr RPM m³/hr 73

74 TIP 7 Cooling Equipment Fan Laws Fan Capacity: Air Flow (m 3 /hr) is proportional to Speed (RPM) of Fan Fan Power: Power (kw) is proportional to the CUBE of [ Fan Speed (RPM) ] 3 Fan Power at Varying Air Flow Air Flow 100% 90% 80% 70% 60% 50% Fan Speed 100% 90% 80% 70% 60% 50% Fan Power 100% 73% 51% 34% 22% 13% Varying the Fan Speed to match the required Air Flow can provide a SIGNIFICANT reduction in energy consumption during PART LOAD conditions 74

75 TIP 7 Cooling Equipment Chiller Sizing & Selection Chiller Compressor kw (power) / kw (cooling) 25% 50% 75% 100% kw Ton Air Cooled 0,19 0,22 0,27 0, kw Water Cooled w/o VFD 0,14 0,11 0,12 0, kw Water Cooled with a VFD 0,09 0,08 0,12 0,16 75

76 TIP 7 Cooling Equipment Cooling Tower (Evaporative) Warmer Process Water - Return Warmer, More Humid Ambient Air Ambient Air Colder Process Water - Supply Considerations in the optimization of cooling tower energy efficiency 1) Larger capacity tower allows approach temperature (difference between wet bulb and Colder Process Water - Supply) to be reduced 2) Variable speed fans and energy efficient motors 76

77 TIP 7 Cooling Equipment Drycooler (Sensible) Warmer Process Fluid - Return Warmer Ambient Air Ambient Air Colder Process Fluid - Supply Considerations in the optimization of dry cooler efficiency: 1) Larger coil to fan size ratios will increase energy efficiency 2) Variable speed fans and energy efficient motors 3) Some drycoolers include evaporative spray cooling 77