BEST PRACTICES for ENERGY EFFICIENT DATA CENTERS INDENTIFIED

BEST PRACTICES for ENERGY EFFICIENT DATA CENTERS INDENTIFIED THROUGH CASE STUDIES and DEMONSTRATION PROJECTS Authors: William Tschudi, Lawrence Berkeley National Lab Stephen Fok, Pacific Gas and Electric Company Presented at ASHRAE Winter Meeting in Dallas, Texas January 31, 2007

BEST PRACTICES for ENERGY EFFICIENT DATA CENTERS INDENTIFIED THROUGH CASE STUDIES and DEMONSTRATION PROJECTS q q Northern California service territory including the Silicon Valley Estimated 400 -500 MW of Data Center electricity load in our service territory Partnering with LBNL in addressing Data Center Energy Efficiency Opportunities & Emerging Technologies In 2006, major utility EE Program Implementation produced 132 MW and 677 GWh in Electricity Savings

BEST PRACTICES for ENERGY EFFICIENT DATA CENTERS INDENTIFIED THROUGH CASE STUDIES and DEMONSTRATION PROJECTS OVERVIEW: q q q q LBNL Data Center Benchmarking - Roadmap Best Practices and Design Guidelines Sourcebook Air Management Demonstration Air Economizer Demonstration Centralized Air Handling Case Study Free Cooling using Water-Side Economizer Case Study Efficient Uninterruptible Power Supplies Case Study Q&A

LBNL Data Center Benchmarking A “research roadmap” was developed for the California Energy Commission and outlined key areas for energy efficiency research, development, and demonstration

LBNL Data Center Benchmarking 23 Data Center Case Studies q Banks/financial institutions q Web hosting q Internet service provider q Scientific Computing q Recovery center q Tax processing q Storage and router manufacturers

LBNL Data Center Benchmarking IT equipment load density

Benchmarking energy end use

Overall power use in Data Centers Courtesy of Intel Corporation

Data Center performance differences

HVAC system effectiveness We observed a wide variation in HVAC performance

Best Practices topics identified through Benchmarking

CA utility Design Guidelines Sourcebook Guides available through Energy Design Resources Website

Air Management Demonstration Goal: Demonstrate better cooling and energy savings through improvements in air distribution in a typical and a high density environment.

Air Management Demonstration – High Density Data Center n The as-found conditions were monitored – – – n Temperatures Fan energy IT energy An area containing two high-intensity rows and three computer room air conditioning units was physically isolated from rest of the center – approximately 175 W/sf

Air Mgmt Demo, High Density Data Center - (First alternate) Cold Aisle Isolation

Air Mgmt Demo, High Density Data Center - (Second Alternate): Hot Aisle Isolation

Air Mgmt Demo, High Density Data Center - Procedure n n n Once test area was isolated, air conditioner fan speed was reduced using existing VFD’s Temperatures at the servers were monitored IT equipment and fan energy were monitored Chilled water temperatures were monitored Hot aisle return air temperatures were monitored – ΔT was determined

Air Mgmt Demo, High Density Data Center - Fan energy savings: 75% Since there was no mixing of cold supply air with hot return air fan speed could be reduced

Air Mgmt Demo, High Density Data Center - Better temp control would allow raising the temp in the entire data center ASHRAE Recommended Ranges during demonstration

Air Mgmt Demo, High Density Data Center n n Since air is not mixing, the overall air supply temperature could be raised (typically centers are below ASHRAE recommended minimums because of mixing) Hotter air is returned to the computer room air conditioners - Larger temperature difference (ΔT) allows air conditioning unit to have more capacity

Air Economizer Demonstration n n Goal: encourage use of outside air economizers where climate is appropriate Strategy: – address data center professional’s biggest concerns: contamination and humidity control – quantify energy savings at one center

Air Economizer Demonstration n n Total of EIGHT data centers were studied. Snapshot/monitoring over several days Continuous monitoring equipment in place at one center. Data collection over several months Before and after capability at TWO centers Energy savings estimate based on utility billing records.

Air Economizer Demonstration n n Water soluble salts in combination with high humidity can cause failures Static electricity can occur with very low humidity Humidity control for make-up air (or no controls) is usually sufficient Particle concentrations with normal filtration are orders of magnitude lower than recommended Site No. 8 energy savings was estimated to be about 1% of total energy depending on economizer set point.

Air Economizer Demo - Contamination is orders of magnitude less at servers

Air Economizer Demo - Particle Concentrations by Size

Centralized Air Handling Case Study n n n Utilize larger & more efficient fans and motors vs CRAC Use of variable frequency drives Located outside of the data center enhances space allocation and maintenance of IT equipment

Free Cooling using Water-Side Economizer Case Study n n n Best suited for climates with wet bulb temp < 55 deg F for >3000 hrs per year Very effective for chilled water systems designed for >50 deg F Possible chilled water plant energy savings of up to 75%

Efficient Uninterruptible Power Supplies Case Study (1) At the same level of redundancy, approx 5% efficiency gains is possible from operating the UPS at 33% vs 25% of full load (2) Additional HVAC savings improves life cycle costing

Best Practices for Energy Efficient Data Centers Identified through Case Studies and Demonstration Projects - Q & A William Tschudi, P. E. : E-Mail – WFTschudi@lbl. gov Stephen Fok, P. E. : E-Mail – skf 2@pge. com