Docstoc

Energy Efficient Data Centers

Document Sample
Energy Efficient Data Centers Powered By Docstoc
					Energy Efficient Data Centers
Update on LBNL data center energy efficiency projects

June 23, 2005 Bill Tschudi Lawrence Berkeley National Laboratory
Wftschudi@lbl.gov

LBNL’s energy research related to data centers
    

   

Energy research roadmap Case studies and energy benchmarking Best practice identification Self benchmarking protocol Investigate efficiency of power supplies in IT equipment Investigate efficiency of UPS systems Metrics for computing performance vs. energy Technology transfer Demonstration projects

Data center efficiency opportunity


Many efficiency ideas have been identified through industry feedback Case studies are helping to identify best practices



Data center efficiency resources


ASHRAE “Thermal Guidelines for Data Processing Environments” ASHRAE “Power Trends and Cooling Applications” In preparation: ASHRAE “Design Considerations for Data Center and Communications Equipment Centers” which includes a chapter on energy efficiency

 

Case studies/benchmarks


California
•

•
• • • •

Storage device and router Mfgs. Banks

Web hosting facilities Internet service provider State tax center Federal facilities



New York
• •

Recovery center (hosting) Financial institution

IT equipment load intensities
Data collected in 1999 through 2003 showed that electrical power intensity for IT equipment alone was on the order of 25 Watts/sf. Current data suggests that load intensities are rising through compaction and/or due to rising equipment power consumption.

2003 IT equipment loads from LBNL case studies

Average 27 +/-

(W/sf of electrically active floor space using Uptime definition)

2003 projections if fully loaded

Projected Average 44

(W/sf of electrically active floor space using Uptime definition)

Distribution of computer load intensities reported to Uptime Institute
1.00

Fraction of total floor area in sample

2000 1999 2001

0.80

0.60

Source: Uptime Institute, 2002.
Number of facilities 1999 2000 2001 35 38 48 Total floor area Million square feet 1.55 1.72 1.86 Computer room power density W/square foot 22.9 22.4 25.3

0.40

0.20

0.00 0 20 40 60 80 100 Computer room UPS power (Watts/square foot)

2005 IT equipment benchmarks

IT equipment load 100 90 80 70

Average 52 w/sf

LBNL NERSC supercomputer

Watts/sf

60 50 40 30 20 10 0 1 2 3 4 5 6 7 Data center identifier

Electrical power conversion is a big opportunity
Every conversion of AC voltage, AC to DC, DC to AC, or DC voltage conversion results in loss of electrical power and corresponding heat that must be removed from the data center. Minimizing this conversion loss has a magnifying effect that allows all facility systems to use less energy and consequently the infrastructure systems can be downsized.

Saving say 10% on the conversion loss could result in 20% or more saving for the facility.

How many times do data centers convert AC and DC?
AC voltage conversions
5V Internal Drive
12V

Bypass In Battery/Charger Rectifier Out
AC/DC PWM/PFC Switcher Unregulated DC To Multi Output Regulated DC Voltages

External Drive
I/O

3.3V 12V DC/DC
12V DC/DC 3.3V 3.3V 1.5/2. 5V 1.1V1.85V

Memory Controller m Processor

Inverter

SDRAM
Graphics Controller

Voltage Regulator Modules

AC/DC Multi output PS

Measured Efficiencyefficiency UPS UPS
100 80

Efficiency (%)

60

40

20

0 0 20 40 60 80 100

Load Factor (% )

Measured UPS losses
Factory Measurements of UPS Efficiency
(tested using linear loads) 100% 95% 90% 85% 80% 75% 70% 0% 20% 40% 60% 80% 100% Percent of Rated Active Power Load
Flywheel UPS Double-Conversion UPS Line-Interactive, Delta Conversion UPS

Efficiency

Measured UPS losses
Factory Measurements of UPS Efficiency
(tested using non-linear loads)

100% 95%
Efficiency

90% 85% 80%
Double Conversion UPS

75% 70% 0% 20% 40%

Line-Interactive, Delta Conversion UPS

60%

80%

100%

Percent of Rated Active Power Load

Electricity use in a server
140 120 100 80 60 40 20 0 131 72 32
AC DC Losses DC/DC Losses

86 41 27
Processors Memory

32
Drives

32
Chipset

Based on a typical dual processor 450W 2U Server; Approximately 160W out of 450W (35%) are losses in the power conversion process (Source: Brian Griffith: INTEL)

PCI Cards

Fans

Power supply opportunity
HVAC Chilled Water 1190 2380 Standby Generator Lighting and Plug Loads 85 170 4335 340 Computing Load HVAC Fan Load UPS Losses

Efficiency of Power Conversion Process 65% 70% 75% 80% 85% 90%

IT Load (kW) 4335 4025 3757 3522 3315 3131

UPS Losses (kW) 340 316 295 276 260 246

Total Savings (kW) 0 334 623 877 1100 1299

Based on one case study approximately 4335 KW of a total of 8500 kW was IT load. Assuming a 65% existing baseline efficiency, the savings opportunity using 90% efficient conversion process is approximately 1300kW not including any savings from HVAC

Power supply efficiency recommendations
The Server Systems Infrastructure group (SSI) publishes recommended minimum efficiencies for server power supplies. The LBNL project team is working with this group to see what can be done to raise the bar.

Power supply efficiency today

Full Load Efficiency > 68%

Redundant System of Power Supplies for Servers

68

Measured power supply efficiency
85% 80% 75%

% Efficiency

70% 65% 60% 55% Average of All Servers 50% 45% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% % of Nameplate Power Output

Energy efficiency opportunity
Specifiers of UPS’s or IT equipment can have a huge impact on energy use by requiring higher efficiencies. Testing data shows that higher efficiencies can be obtained – you have to ask for it. Facility and IT professionals by working together can optimize overall power conversions. Additional costs (if any) for more efficient conversions will have a very short payback or may be entirely justified by reductions in infrastructure.

Effectiveness of HVAC systems
HVAC (as a % of total load)
60% 50%

% of total load

40% 30% 20% 10% 0% 1 2 3 4 5 6 7 8 9 10 11 12 Data Center Identifier

Index of performance
The Uptime Institute proposed a metric to evaluate the total efficiency of infrastructure systems: Index of performance = building systems KW  UPS output
(i.e. ratio of building systems to IT equipment load)

Look at the end-use
Data Center A
Total Power = 580 kW
UPS Losses 6%

Data Center B
Computer Loads 63%

Total Power = 1700 kW

Computer Loads 38%

HVAC 54% Lighting 2%

UPS Losses 13%

Lighting 1%

HVAC Chilled Water Plant 14%

HVAC - Air Movement 9%

LBNL high-tech buildings website:

http://hightech.lbl.gov


				
DOCUMENT INFO
Shared By:
Categories:
Stats:
views:127
posted:4/27/2008
language:English
pages:25