Objective Explore why saving energy in Data Centers? Get a general - PowerPoint PPT Presentation

Saving Energy in Data Centers Low Cost Energy Efficiency Measures Case Studies September 2013 Rod Mahdavi, PE. LEED AP Building Technologies Lawrence Berkeley National Laboratory (LBNL) Slide 1

Objective • Explore why saving energy in Data Centers? • Get a general idea of the best practices • Learn about low cost EEMs • Environmental conditions adjustments • Air management improvements • Chiller Plant • Examine three Case studies Slide 2

High Tech Buildings are Energy Hogs: Slide 3

US Data Center Electricity Use - 2000, 2005, and 2010 2% of US Electricity consumption Potential to double in next 5 years Source: Koomey 2011 Slide 4

Data Center Energy Efficiency = 15% (or less) (Energy Efficiency = Useful computation / Total Source Energy) Typical Data Center Energy End Use 100 Units Source Power Conversions Energy & Distribution Cooling 35 Units Equipment Power Generation Server Load /Computing Operations 33 Units Delivered Slide 5

Energy efficiency best practices • Server innovation • Better air management • Virtualization • Move to liquid cooling • High efficiency • Optimized chilled-water plants • Use of free cooling power supplies • Load management • Heat recovery Power Server Load/ Cooling Conversion & Computing Distribution Operations • On-site generation • High voltage distribution Including fuel cells and • High efficiency UPS systems renewable sources • Efficient redundancy strategies Alternative • CHP applications Power • Use of DC power Generation (Waste heat for cooling) Slide 6

LBNL develops publically available resources DC Pro tools Federal consolidation Data Center Energy Practitioner guideline program ESPC contract content Computing metrics development Wireless assessment kit Compressor- less cooling Slide 7 7

Low Cost EEMs : • Environmental conditions adjustments • Air management improvements • Chiller plant Slide 8

Low Cost EEMs : • Environmental conditions adjustments • Air management improvements • Chiller plant Slide 9

ASHRAE 2011 Slide 10

The Cost of Unnecessary Humidification Visalia Probe CRAC Unit Panel Temp RH Tdp Temp RH Tdp Mode AC 005 84.0 27.5 47.0 76 32.0 44.1 Cooling AC 006 81.8 28.5 46.1 55 51.0 37.2 Cooling & Dehumidification AC 007 72.8 38.5 46.1 70 47.0 48.9 Cooling AC 008 80.0 31.5 47.2 74 43.0 50.2 Cooling & Humidification AC 010 77.5 32.8 46.1 68 45.0 45.9 Cooling AC 011 78.9 31.4 46.1 70 43.0 46.6 Cooling & Humidification Min 72.8 27.5 46.1 55.0 32.0 37.2 Max 84.0 38.5 47.2 76.0 51.0 50.2 Avg 79.2 31.7 46.4 68.8 43.5 45.5 Humidity down 3% CRAC power down 28% Slide 11

Low Cost EEMs : • Environmental conditions adjustments • Air management improvements • Chiller plant Slide 12

Goal: Supply air directly to equipment intakes without mixing Cool Front Hot Rear Aisle Aisle Equip. Rack No Air No Air Mixing Mixing 13 Slide 13

By-pass air does no cooling Misplaced perforated tiles Too much supply airflow Leaky cable penetrations Too high tile exit velocity 14 Slide 14

Recirculated air causes localized cooling problems Recirculation Air Short equipment rows Equip. Rack Lack of blanking panels Gaps between racks Too little air supply Slide 15

Adding Air Curtains for Hot/Cold Isolation Slide 16

95-105ºF vs. 60-70ºF (35-41 C vs. 16-21C) 70-80ºF vs. 45-55ºF (21-27C vs. 7-13C) Slide 17

Low Cost EEMs : • Environmental conditions adjustments • Air management improvements • Chiller Plant Slide 18

Better efficiency of chiller with higher load factor Chiller 4 Performance Sep 17 - 22, 2012 1.8 1.6 Maximum efficiency at the full Maximum guaranteed efficiency at the chiller rated 1.4 capacity as provided by the capacity of 2250 tons = 0.565 kW/ton, as per Drawing Chiller Efficiency (kW/ton) manufacturer M-611 in the file "2010-01-10 NGA-NCE CUP Drawings 1.2 (CONFORMED SET).pdf". 1.0 0.8 0.6 0.4 0.2 0.0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Chiller Load Factor Slide 19

Condenser water supply temperature Chiller 4 Condenser Water Temp and Outside Air Wetbulb Temp 90 80 Temperature (F) 70 60 CW Temp 50 OA Wetbulb 40 9/16 9/17 9/18 9/19 9/20 9/21 9/22 9/23 9/24 Slide 20

Federal Data centers Case studies Data center 1 5,000 sf UPS room Pumps 500 kW IT cooling, 1% Generator 8GWh BH Chillers 3% 26% IT Equipment Tropical climate 53% Air-cooled Chillers CRAHs CRAH Fans/Heater 8% UPS+PDU Lighting Losses 1% 8% Slide 21

Case studies Seal all floor leaks and those between and within the racks Slide 22

Case studies Lesson learned: Seal the opening between the rack and floor Supply Air temperature out of the perf tiles = 61.6degF Slide 23

Case studies Air temperature between perf and rack pedestal= 89.1degF Slide 24

Case studies Air temperature after space taped = 69.3degF Slide 25

Case studies Replaced Perf tiles Redirect cold air from the CRAHs Slide 26

Case studies Ceiling space as a plenum Slide 27

Case studies Before trials begin After RAT increased from 74degF to 84degF Slide 28

Case studies Individual racks intake top temperature change during trials (60-72) Average rack exhaust temperature change during trials (75-87) Slide 29

Case studies CRAHs Supply Avg. Temperatures 53 to 62 CRAHs Return Avg. Temperatures 64 to 83 Slide 30

Case studies Chillers Efficiency Improvement 260 58 56 240 54 220 52 200 50 Chiller plant kW 180 48 CHWST 160 46 140 44 120 42 100 40 1 2 3 4 45 49 54 56 CHWST sp degF 46 49 55.1 56.8 CHWST degF 75 75 0 0 CH1 kW 75 75 100 75 CH2 kW 75 50 75 75 CH3 kW Slide 31

Case studies Saved annually: 800MWh $240,000 utility cost 780 metric tons of GHG emission Slide 32

Case studies Data center 2 UPS cooling 30,000 sf 3% Fans 1,850 kW IT 11% Cooling 30GWh 16% IT Load Lighting 56% 2% Standby Gen 1% PDU/trans UPS Loss loss 9% 2% Slide 33

Case studies Air management issues Slide 34

Case studies Top rack intake temp before shutting down 20% of the CRAHs Top rack intake temp after Slide 35

Case studies Little rack intake temperature change after CRAHs shutdown Slide 36

Case studies Saved annually: 850MWh $55,000 utility cost 820 metric tons of GHG emission 2000 1800 1600 1400 1200 1000 800 CURRENT 600 POTENTIAL 400 200 0 Slide 37

Case studies Data center 3 8,000 sf Cooling 800 kW IT Fans 28% 6% 12GWh Current IT Load 59% Lighting 1% Standby Gen 1% PDU/trans loss 2% UPS Loss 3% Slide 38

Case studies Slide 39

Case studies Dry Cooler TES Ceiling return air plenum Rack Door HX COIL hot aisle containment CENTRAL AIR HANDLERs Under raised floor supply air plenum Slide 40

Case studies Slide 41

Case studies Slide 42

Case studies Reduction of water flow to TES from 1,000 to 300 gpm 1.80 1.75 Pump power reduced 1.70 Chiller more efficient 1.65 1.60 (higher delta T and 1.55 1.50 load factor) 1.45 1.40 PUE improved 1.35 Slide 43

Case studies Saved annually: 2,100MWh, $125,000 utility cost 2,000 metric tons of GHG emission Slide 44

Case studies Questions? Rod Mahdavi, PE. LEED AP rmahdavi@lbl.gov 510.495.2259 Slide 45