Top 10 energy conservation measures for data centers. Presented by: Michael G. Bushell, P.E. Willdan Energy Solutions Chicago, Illinois

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1 Top 10 energy conservation measures for data centers Presented by: Michael G. Bushell, P.E. Willdan Energy Solutions Chicago, Illinois December 11, 2014 Top 10 energy conservation measures for data centers by ENERGY CENTER OF WISCONSIN Approved for: 1.5 General CE hours 0 LEED-specific hours GBCI cannot guarantee that course sessions will be delivered to you as submitted to GBCI. However, any course found to be in violation of the standards of the program, or otherwise contrary to the mission of GBCI, shall be removed. Your course evaluations will help us uphold these standards.. Approval date: 11/10/2014 Course ID:

2 Produced in partnership with Our ECU online sponsors PLATINUM SPONSORS GOLD SPONSORS

3 Welcome Continuing education credit Slides as PDF Share your feedback Poll questions Chat balloon Webinar Learning Objectives Understand the most common energy efficiency measures specific to data centers Understand where different energy efficiency measures apply and don t apply Identify the pros and cons associated with those measures Estimate the expected savings associated with energy efficiency measures

4 Agenda Speaker Background Data Center Background Common Energy Conservation Measures Other Energy Measures Closing / Questions Speaker Background B.S. Mechanical Engineering U.W. Madison MBA Kellstadt Graduate School of Business DePaul University Past Experience KJWW Engineering MEPFP consulting Eaton Corporation Cx/RCx, ESPC, data centers Current Willdan Energy Solutions Data Center Program Manager Licensed P.E. Wisconsin, Illinois and Indiana

5 Why Data Centers? Data centers can use up to 200 times more electricity than standard office spaces In 2010, U.S. data centers consumed nearly 100 billion kwh, roughly 2% of the country s total power consumption 9 Reducing energy in data centers saves money Growing demand for IT means growing demand for power-hungry data centers Importance In Economies Continuous capital improvement cycles for most facilities Increased focus on energy efficiency opportunities balanced against a need for 100% reliability ASHRAE does include data centers PUE compliance path Addendum AP in ASHRAE Fully adopted in ASHRAE

6 Energy Conservation Top Ten 1. CRAC / CRAH Unit Upgrades 2. UPS / PDU Upgrades 3. Humidification Upgrades 4. Hot Aisle, Cold Aisle Layout 5. Economizer 6. Variable Frequency Drives 7. Airflow Management 8. Motor Replacement 9. Chiller Measures 10. IT Measures 11. Other Measures NUMBER ONE CRAC / CRAH Unit Upgrades

7 (1) CRAC / CRAH Unit Upgrades - Summary CRAC Computer Room Air Conditioning (DX) Low Efficiency High Efficiency Condensers Dry Cooler Dry Cooler Evaporative Cooling CRAH Computer Room Air Handling (Chilled Water) Low Efficiency High Efficiency Direct Expansion Chilled Water Source: (1) CRAC / CRAH Unit Upgrades - Summary

8 (1) CRAC / CRAH Unit Upgrades - Application CRAC Units Capacity Range 3.5 KW 150 KW Used when chilled water is not available / cost prohibitive Typically smaller installations Fan speeds typically limited to 65%-70% due to coil freezing concerns CRAH Units Capacity Range 26 KW 181 KW Used in conjunction with a dedicated or central plant chilled water system Typically larger installations No lower limit to fan speeds, with the exception of motor cooling (1) CRAC / CRAH Unit Upgrades - Comparison Pros Significant energy savings potential (1.6+ kw/ton to 0.4 kw/ton) Many small options / upgrades result in large savings (e.g.: compressors, motors, fans, controls, VFD, new generation eqpm.) Cons Capital Intensive Incentive programs usually only incent on incremental value of equipment upgrade Changing system type is frequently prohibitive

9 (1) CRAC / CRAH Unit Upgrades - Calculations NUMBER TWO UPS / PDU Upgrades

10 (2) UPS / PDU Upgrades - Summary Uninterruptible Power Supplies (UPS) use an internal battery to provide short-term power until the generators start in case of input power source failure Batteries use DC power: therefore, a UPS must rectify incoming AC power to DC power, and then invert that power back to AC power (2) UPS / PDU Upgrades - Application All data centers supply their IT power through a UPS Reliability issues usually yield redundant UPS units at low load Typical layout has A and B source UPS units, each loaded to a maximum of 40%, so if one fails, the other automatically picks up the load and runs at 80% load Energy Inefficiencies Occur At each AC/DC conversion When UPS is not properly loaded

11 (2) UPS / PDU Upgrades - Application Source: (2) UPS / PDU Upgrades - Comparison Pros New UPS can achieve up to 98% published efficiency Properly loading units can still yield reliability, yet force units to operate at a better point on curve Indirect cooling savings Cons Replacing a UPS is capital intensive Perceived reliability issues Incentive programs usually only incent on incremental value of equipment upgrade meaning customer needs capital

12 (2) UPS / PDU Upgrades - Calculations NUMBER THREE Humidification Upgrades

13 (3) Humidification Upgrades - Summary Traditional Water is heated and introduced into air stream High kw load to essentially boil water Adds heat to air stream = more cooling Ultrasonic Ultrasonic frequency Lower kw (80%-90%) No added cooling load Source: (3) Humidification Upgrades - Application Humidifier Installation Climate dependent Source:

14 (3) Humidification Upgrades - Comparison Pros Significant energy savings - up to 90% savings Depending on duty cycle and runtime, ROI can be as low as a couple years Cons Equipment cost can be 2x 4x more than traditional humidifiers Low ROI can be used to bring down total project ROI (3) Humidification Upgrades - Calculations

15 QUICK BREAK Webinar Reminders NUMBER FOUR Hot Aisle, Cold Aisle Layout

16 (4) Hot Aisle, Cold Aisle Layout - Summary Air delivered to the space is traditionally used to cool equipment Ignore immersion, in-row and enclosed racks for now. Goal is to deliver cold air where it is needed and remove hot air where it is produced Mixing is your enemy! Solution: Lay out rack in parallel rows and designate hot and cold zones (4) Hot Aisle, Cold Aisle Layout - Summary

17 (4) Hot Aisle, Cold Aisle Layout - Application Basic data center design Should be employed in all new data centers Renovated data centers should seriously consider Strategy can be employed from very small to very large Most commonly coupled with a raised floor distribution, but can be done with ductwork (4) Hot Aisle, Cold Aisle Layout - Comparison Pros Tries to deliver air to where it is needed Attempts to decouple hot and cold airstreams Begins to address mixing Cons Limited effectiveness with free discharge supply and common return Employed alone will not necessarily save energy Only the first step in airflow management Challenging to move racks

18 (4) Hot Aisle, Cold Aisle Layout - Calculations Source: (4) Hot Aisle, Cold Aisle Layout - Calculations Source:

19 (4) Hot Aisle, Cold Aisle Layout - Calculations Source: NUMBER FIVE Economizer

20 (5) Economizer - Summary Free cooling: When the outside air temp T is favorable, mechanical cooling (use of compressor) is not required Example: if a data center near JFK switches to free cooling when outside air 50, 3646 hours of compressor use are saved (5) Economizer - Application In this air-cooled system, outside air is brought in directly based on sensors and dampers Energy savings from reduced hours of compressor use Source:

21 (5) Economizer - Application Source: (5) Economizer - Application In this water-cooled system, valves located before and after the condenser allow the water to bypass the rest of the cycle The economizer is a coil that the same evaporator (supply) fan can blow data center air across in order to cool it economizer CRAC unit

22 (5) Economizer - Application In this water-cooled system, condenser water bypasses the condenser bundle in the centrifugal chiller via heat exchanger Energy savings from reduced chiller run hours Source: (5) Economizer - Comparison Pros Significant energy savings Reduce compressor run time by 75%+ (in favorable climate) Incremental ROI for integrating waterside economizer usually less than 2 years Cons IT staff may have pollution and humidity concerns with direct airside economizer Challenging to add airside econ ductwork in renovation Adding a HX could require significant piping (depending on conditions)

23 (5) Economizer - Calculations Water Side Chiller Analysis must be performed at all weather conditions Typically use ASHRAE 1% or 0.4% values 5 increments usually acceptable 42 F CHWS Compressor off at approx. 32 F 37 F Pre kwh 15 to 95 Post kwh 37 to 95 Energy Savings NUMBER SIX Variable Frequency Drives

24 (6) Variable Frequency Drives - Summary Variable Frequency Drive (VFD) or Variable Speed Drive (VSD) same thing Varies input frequency and voltage to reduce or increase speed of motor Source: (6) Variable Frequency Drives - Application Almost always three phase motors Can be installed on: Pumps Fans Cooling Towers Compressors Chillers (but more on this later ) Source: New or retrofit applications

25 (6) Variable Frequency Drives - Comparison Pros Very quick ROI (1-3 years) Usually not a significant upfront cost per VFD Easy and widespread way to save energy Installation is not as disruptive as other ECMs Cons Might require controls upgrades in retrofit situation, which can increase ROI Requires an actual reduction in motor speed (installing them alone without operational changes actually decreases efficiency) (6) Variable Frequency Drives - Calculations Motor savings = # Equation needs to be performed for each horsepower is a conversion of horsepower to kilowatts Motor loading factor can be estimated at 90%, measured is better Motor efficiency can be estimated at 90%, measured is better Runtime hours is probably 8760 for a data center VFD speed can be estimated at 80%, measured is better

26 NUMBER SEVEN Airflow Management (7) Airflow Management - Summary Subfloor partitioning Adding subfloor barriers to reduce airflow to areas not requiring cooling Adding subfloor barriers to designate certain CRAC/CRAH units for specific zones Sealing Plenum Identify leaks in plenum and seal Broken gaskets, cable pulls, missing tiles

27 (7) Airflow Management - Summary Floor Tile Management Identify hot / cold spots and install / remove tiles as applicable Install appropriate flow tiles (high flow, low flow, damper controlled) Containment Installing solid panels, doors, ceiling and/or curtains in either the hot aisle or cold aisle Shrinks the control volume where air is delivered (7) Airflow Management - Summary Source:

28 (7) Airflow Management - Application Specific to raised floor air delivery system Subfloor Partitioning Applied when IT footprint is shrinking, but raised floor square footage remains Sealing Plenum Good practice Floor Tile Management If function has shifted from the original design (7) Airflow Management - Application Containment Hot aisle cold aisle layout required Underfloor air delivery or return required Can be hot aisle OR cold aisle containment Servers must be installed correctly Does not save energy by itself Increase Chilled Water Setpoint Increase LAT Setpoint Fan Speed Reduction (VFD)

29 (7) Airflow Management - Comparison Pros Eliminates hot air and cold air stream mixing Allows for fan speed reduction, CRAC LAT increases and chiller CHWS temp increases ROI regularly 1-4 years Cons Does not save energy alone needs to be coupled with other measures Depending on size and type, potentially large up front cost More challenging to install with overhead cabling (7) Airflow Management - Calculations CRAH Savings - EC Fan and Cold Aisle Containment on the 3rd floor Unit Model Number Total Number Supply Fan amp of Units draw per unit Supply Fan Power per unit (kw) Base Case Baseline Fan Motor Speed Fan Motor Run Hours kw Demand kwh Consumption A % 8, ,734 B % 8, ,435 C % 8, ,415 Base Case Total ,584 Proposed Case Unit Model Total Number Supply Fan amp Supply Fan Post M&V EC Fan Motor Run kwh kw Demand Number of Units draw per unit Power (kw) Fan Speed (%) Hours Consumption A % 8, ,945 B % 8, ,893 C % 8, ,759 Proposed Case Total ,596 kw Savings 36.4 kwh Savings 318,988

30 NUMBER EIGHT Motor Replacement (8) Motor Replacement - Summary Three Ways to Save 1. Horsepower reduction Reduce HP req d, better match HP to application 2. High / premium efficiency motors Select/replace motor with higher efficiency 3. Electrically Commutated Motors (ECM) Brushless synchronous motors (no slip)

31 (8) Motor Replacement - Application Energy loss is mainly heat coil winding (resistance) loss in the rotor bars and slip rings loss due to magnetizing of the iron core loss from friction of bearings (8) Motor Replacement - Application Electrically Commutated Motors (ECM) Permanent magnets rotate around a fixed armature, eliminating problems associated with connecting current to the moving armature More torque per weight and per watt (increased efficiency) Increased reliability Reduced noise Longer lifetime (no brush and commutator erosion) Elimination of ionizing sparks from the commutator Overall reduction of electromagnetic interference (EMI)

32 (8) Motor Replacement - Comparison Pros 10%-20% efficiency gains possible EC Motors greater efficiency, torque, reliability, lifespan, lower noise Cons The more efficient the motor, the more expensive. ECM motors are more expensive than regular motors (8) Motor Replacement - Comparison Source:

33 (8) Motor Replacement - Pre Calculations CRAH Unit EC Fan Retrofit Total Number of Units Rated Nominal Tonnage of Each Unit (tons) Baseline Fan Motor Speed Base Case Fan Energy Baseline Fan Motor Power (HP) Baseline Power Consumption (kw) Fan Motor Run Hours kw Demand kwh Consumption % , ,743,099 Total Number of Units Rated Nominal Tonnage of Each Unit (tons) Proposed Fan Motor Speed Proposed Case Fan Energy Proposed Fan Motor Power (HP) Proposed Power Consumption (kw) Fan Motor Run Hours kw Demand kwh Consumption % , ,165 Upgraded Controls Energy Savings Total Demand Savings kw Total Consumption Savings 1,151,934 kwh (8) Motor Replacement - Post Calculations CRAH Unit EC Fan Retrofit Total Number of Units Rated Nominal Tonnage of Each Unit (tons) Baseline Fan Motor Speed Base Case Fan Energy Baseline Fan Motor Power (HP) Baseline Power Consumption (kw) Fan Motor Run Hours kw Demand kwh Consumption % , ,743,099 Location Total Number of Units Rated Nominal Tonnage of Each Unit (tons) Proposed Case Fan Energy Proposed Fan Motor Speed Proposed Power Consumption (kw) Fan Motor Run Hours kw Demand kwh Consumption Room % , ,757 Room % , ,355 Room % , ,765 Room % , ,664 Room % , ,562 Room % , ,459 Room % , ,038 Room % , ,664 Upgraded Controls Energy Savings Total Demand Savings kw Total Consumption Savings 1,373,835 kwh

34 NUMBER NINE Chiller Measures (9) Chiller Measures - Summary Chiller Efficiency depends on: Manufacturer Style (air cooled vs. water cooled) Load Conditions Evaporator and Condenser Water Temperatures Compressor Type OA Conditions Control Schemes, VFDs and Staging Refrigerant Heat Exchanger Area So what do we actually care about?

35 (9) Chiller Measures - Summary Most important efficiency factor is system kw/ton at load conditions Air-Cooled Chiller kw/ton Water-Cooled Chiller kw/ton (9) Chiller Measures - Application Source:

36 (9) Chiller Measures - Application Source: (9) Chiller Measures - Comparison Pros A chiller plant with low kw/ton chillers automatically operating at an optimal point, coupled with economizer, VFD, staging and water temperature management, arguably results in the largest savings potential Cons Chiller measures are not cheap More copper + more technology = $$$ Upfront cost greater for more efficient machines

37 (9) Chiller Measures - Calculations 1. Understand kw/ton curve 2. Determine tonnage required at weather conditions in 5 increments 3. Match tonnage to kw/ton 4. Incorporate economizer shutoff conditions 5. Summation of kw at all conditions 6. Pre kw Post kw = Savings NUMBER TEN IT Measures

38 (10) IT Measures - Summary Virtualization Consolidation of underutilized equipment Thin Client Provisioning Replacing point of use computers/equipment with hubs that tie back to a central server/station Decommissioning Removal of equipment no longer being used Technology Refresh Replacement / upgrade of existing servers to newer generations (10) IT Measures - Summary Source: Source:

39 (10) IT Measures - Application Virtualization Large decentralized data centers with underutilized servers Thin Client Provisioning Widespread use of computers Decommissioning Everywhere if something is not being used but is still plugged in, remove it (10) IT Measures - Comparison Pros All measures can save significant energy (up to 90%) Cons Virtualization requires upfront equipment and a shift in IT mentality Servers serving discrete systems (like security or access control) might not be compatible with virtualization

40 (10) IT Measures - Calculations Virtualization Subtract sum all servers to be removed Add all virtualization master servers added Thin Provisioning Subtract sum all computers to be removed Add all thin clients hubs added Other Measures

41 (11) Immersion cooling Source: (11) In row cooling Source: Source:

42 (11) Cooling Tower Measures Source: Source: Energy Conservation Top Ten 1. CRAC / CRAH Unit Upgrades ROI: years, Savings: 36% 67% 2. UPS / PDU Upgrades ROI: years, Savings: 3% 17% 3. Humidification Upgrades ROI: 5.1 years, Savings: 90% 4. Hot Aisle, Cold Aisle Layout ROI: 2.2 years, Savings: 22% 5. Economizer ROI: years, Savings: 2.3% 49% 6. Variable Frequency Drives ROI: years, Savings: 5.8% 74% 7. Airflow Management ROI: years, Savings: 33% 61% 8. Motor Replacement ROI: years, Savings: 78% 81% 9. Chiller Measures ROI: years, Savings: 14% - 65% 10. IT Measures ROI: 6.8 years, Savings: 82% In most cases, ROI is based on incremental cost of implementing more efficient option and not full project cost. The above values are meant to provide guidance of savings and ROI values. The values are indicative of specific projects and do not characterize all projects. Project may have significantly greater or less ROI and savings including 0% savings, depending on specific situation.

43 Closing Thoughts Interactive Effects of Measures ROI of many measures dependent on incremental savings, not total project cost Absolute kwh savings can be much different than relative percentage savings Incentive programs available can buy down ROI on average of 1-2 years PUE can be used to benchmark, but is more informative on an individual data center, not for comparing two different sites Produced in partnership with

44 Our ECU online sponsors PLATINUM SPONSORS GOLD SPONSORS FOCUS ON ENERGY BUSINESS PROGRAM DATA CENTER INCENTIVES FOR BUSINESSES Kari Vokes, EIT Energy Engineer Focus on Energy

45 CURRENT FOCUS ON ENERGY INCENTIVES PRESCRIPTIVE PC Network Energy Management: $6 per PC Energy Efficient Drycoolers: $100 per ton Chillers, Split system air conditioners: varies on size & efficiency ($/ton) Variable Frequency Drives: $50/hp CUSTOM Needs Pre-approval! Custom cooling systems Aisle containment/airflow management Power distribution/uninterruptible power supply retrofits Storage consolidation Other EXAMPLE: SERVER VIRTUALIZATION (CUSTOM) EXISTING Number of Existing Servers: 9 Average Server Operating Watts: 239 PROPOSED Number of Existing Servers: 2 Average Server Operating Watts: 391 ANNUAL ENERGY SAVINGS 2.1 kw 18,286 kwh $1,463 ECONOMICS Project Cost: $4,600 Focus on Energy Incentive: $994 Simple Payback: 2.46 years

46 EX. DATA CENTER COOLING: COMMUNICATION BLDG COLD AISLE CONTAINMENT Measure Cost: $5,500 Annual Energy Savings: 2.8 kw, 14,667 kwh, $1,173 Incentive: $721 Simple Payback: 4.07 years VARIABLE SPEED DRIVE ON FAN Measure Cost: $8,995 Annual Energy Savings: 4.4 kw, 38,426 kwh, $3,074 Incentive: $1,500 ($50/hp) Simple Payback: 2.44 years Packaged Project Simple Payback of 2.87 FOCUS ON ENERGY WEBSITE STAY TUNED FOR 2015 UPDATES!

47 CONTACT FOCUS ON ENERGY Call: Visit: /FOCUSONENERGY 93 Questions? Michael G. Bushell, P.E. Willdan Energy Solutions Chicago, Illinois (312)