Get documents about "Opportunity for Transformer Energy Savings in Data Center PDUs
Description
energy-saving-opportunities-for-transformers pdf
Document Sample
for the
Opportunity for Transformer
Energy Savings
in Data Center PDU’s
Prepared By:
Peter Ouellette
Northern California Regional Manager
Prepared for:
Silicon Valley Leadership Group
Presented:
June 26, 2008
Data Center Energy Summit
www.powersmiths.com
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
Executive Summary
As part of a transformer efficiency study for data centers, Mr. William Tschudi at Lawrence
Berkeley National Laboratory in Berkeley, suggested contacting Mr. Ray Pfeifer with the Silicon
Valley Leadership Group to identify Data Centers that would be interested in participating. A
Yahoo facility and the US Postal Service Data Center were selected.
Measurements found that PDUs using transformers with a DOE CSL3 class efficiency had 60-
70% lower operating cost than the variety of other PDUs measured.
Aggregated savings at one facility with 30 PDUs were estimated at over $250,000 per year with
associated reduction of 760 tons of CO2 annually.
Transformers can make a significant contribution to lowering operating costs and meeting an
organization’s environmental goals.
Observations: US Postal Data Center: Powersmiths “High Efficiency”
Energy Stations:
The Postal Service facility provided additional contribution since they are in the process of
changing out existing “status quo” PDU’s to High Efficiency units that include DOE Candidate
Standard Level-3 (CSL-3) transformers. The DOE established Candidate Standard Level-3 to be
the efficiency level at which transformers deliver the lowest life cycle cost.
U.S. Post Office Data Center; 160,000 sq. ft., - 33,000 sq. ft. dedicated to computer room
raised floor.
Connected Load (PG&E) 3030-kVA, 985-kVA Original UPS, 250-kVA New UPS, 200-kVA of
computer load connected to unprotected utility power
Data from six (6) newly installed Energy Stations (internal transformers meet or exceed DOE
CSL-3 efficiency), at the US Postal Service was recorded manually. Similarities in
performance are very consistent; Operating losses range from 0.310kW to 0.625kW.
Average operating efficiency for the “high efficiency” Energy Stations is 98.4%. PDU (%)
loading range 15%- 30%.
Performance as expected, consistently lower losses (higher efficiency).
Observations: US Postal Data Center, Exiting PDU’s:
Three (3) existing PDU’s were surveyed; these included two Liebert PDU’s and one CPC
PDU. The CPC is original equipment, estimated vintage late 70’s early 80’s.
Operating losses for the three existing PDU’s: CPC #134-1 = 0.619kW, Liebert #148-2 =
2.094kW, Liebert #148-4 = 2.593kW, Total 5.306 kW.
Based on the data gathered, the annual combined losses for these three (3) PDU’s are
roughly 65,618 kWh, costing approximately $13,320.00 per year, calculated at $0.13 utility
rates.
Electricity waste from these three (3) transformers alone is contributing to approximately 48
tons of additional CO2 emissions annually.
PDU % loading: Average 28%, CPC 17%, Liebert 148-2 26%, Liebert 148-4 42%.
1
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
Observations: YAHOO! Data Center, Existing PDU’s:
Three (3) existing PDU’s were surveyed, all Liebert 300-kVA.
Operating losses: PDU #3-2 - 2.527kW, PDU # 5-3 - 6.096kW, PDU # 6-4 2.065kW, Total
10.688kW.
Based on the data gathered, the annual combined losses for these three (3) PDU’s are
roughly 100,156 kWh costing approximately $26,832.00 per year, calculated at $0.12 utility
rates.
Electricity waste from these three PDU’s alone is contributing to approximately 74 tons of
additional CO2 emissions annually.
PDU % loading: Average 45%; PDU 3-2 64%, PDU # 5-3 25%, PDU # 6-4 45%.
General Recommendations
Based on the data measured and current industry best practices we can make the following
recommendations to Silicon Valley Leadership Group:
Going forward SVLG Members should consider design specifications that include
transformers that meet or exceed Dept. of Energy Candidate Standard Level 3 Efficiency,
(CSL-3) for electronic loads.
CSL-3 efficiency transformers have been demonstrated to reduce losses (electricity
waste) by 50-70% over current practice.
Facilities can lower electrical consumption and the attendant GHG emissions with the
installation of CSL-3 efficiency transformers or PDU’s.
On a life cycle basis CSL-3 technology pays for itself many times over through operating
cost.
While the load profile is not rich in harmonics, it is still nonlinear requiring that
transformers be UL listed with the associated load K-Rating.
Measurement Information
The following pages provide PDU performance statistics, energy saving calculations and
environmental contribution.
2
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
US Postal Service Data Center, San Mateo, CA Powersmiths Energy Station Statistics
Powersmiths
Energy Model # KVA Ia Ib Ic %Avg. Van Vbn Vcn Power I THD V THD % Eff. Losses
Station Size Avg. Avg. Avg. Load Avg. Avg. Avg. Factor % AVG % AVG (Kilo-
Location # Watts)
1A-11 TT2656- 225 122 95 99 16.9% 209 209 209 0.964 12.3% 3.2% 98.5% 0.600
22245
1A-10 TT2656- 225 110 113 111 17.8% 209 209 209 0.973 12.5% 3.0% 98.5% 0.603
22244
1G-13 TT2656- 150 78 93 77 19.9% 208 208 207 0.955 13.0% 3.2% 98.5% 0.443
22248
1G-12 TT2656- 150 72 88 81 19.3% 208 208 207 0.954 14.0% 3.1% 98.5% 0.476
22246
1G-4 TT2656- 150 52 67 69 15.0% 209 208 208 0.944 16.0% 3.3% 98.1% 0.419
22247
1G-3 TT2656- 150 61 54 45 12.8% 208 208 208 0.948 16.1% 3.2% 98.3% 0.310
22249
1G-13 TT2656- 150 123 147 123 31.0% 208 208 207 98.5% 0.600
22248
1G-12 TT2656- 150 112 141 128 30.0% 208 208 207 98.5% 0.625
22246
1G-13 & 1G-12 New data recorded on 3/5/08. On a subsequent visit to the US Postal Data Center the lead electrician mentioned additional load had
been added to previously surveyed Energy Stations. New loading data was recorded for comparison purposes to original measurements.
4
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
US Postal Service Data Center - Performance of Existing PDU’s
Random sample of PDUs slated to be replaced by Powersmiths High Efficiency Energy Station
USPS Data
Center Model KVA Ia Ib Ic %Avg. Van Vbn Vcn Power I THD V THD % Eff. Losses
Existing # Size Avg. Avg. Avg. Load Avg. Avg. Avg. Factor % Avg. % Avg. (Kilo-
PDU Watts)
Location #
PDU 148-4 PPA- 125 128 133 177 42.0% 207 206 208 0.91 16.3% 3.2% 95.8% 2.094
Liebert 125C
PDU 148-2 PPA- 125 97 71 106 26.3% 208 208 208 0.81 21.9% 3.1% 91.1% 2.593
Liebert 125C
PDU 134-1 ? 150 49 59 66 16.8% 208 208 207 0.94 14.2% 2.8% 97.0% 0.619
CPC
5
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
Projected Energy, Cost and Environmental Savings – US Postal Service, San Mateo
Thirty-six PDU’s are currently in place at the US Postal Service Data Center. With collected data from three PDU’s being used as an average, the table
below lists Projected Savings and the Environmental contributions that could be realized if Lowest Life Cycle Cost (DOE CSL-3 Class Efficiency) were
incorporated facility-wide. Energy cost base, $0.13 per kWh.
US Postal Service, San Mateo,CA
Aggregated Project Savings with Powersmiths
Peak kW reduction 45.6 kW
Annual kWh reduction 787418.4 kWh
Reduction in Air Conditioning Load 13.2 tons
Cost Analysis
Energy Cost Escalation (above inflation) 3.0%
Existing Energy Rate (kWh) $0.13
Annual Life Cycle Operating Cost & Savings
Operating Cost 20 years 32 years
Existing Transformer(s) $159,840 $ 5,773,968 $ 10,171,668
Powersmiths Transformer(s) $ 52,104 $ 1,882,080 $ 4,293,420
Savings with Powersmiths $107,736 $ 3,891,888 $ 8,878,248
Summary of Environmental Benefits
Annual Reduction in Greenhouse Gases (per EPA) Equivalent Units
480 tons of CO2 90 Acres trees planted
1,570 tons of Coal 60 Car Emissions
3,800 kgs of SO2 70 homes heated
1,630 kgs of NOx
6
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
YAHOO! Data Center, Santa Clara, CA - Performance Statistics of PDUs selected at random
Yahoo D/C Model # KVA Ia Ib Ic %Avg. Van Vbn Vcn Power I THD V THD % Eff. Losses
Liebert Size Avg. Avg. Avg. Load Avg. Avg. Avg. Factor % Avg. % Avg. (Kilo-
Samples Watts)
PDU 6-4 821862- 300 397 360 362 44.8% 207 208 208 0.96 11.6% 3.2% 98.4% 2.065
071
PDU 5-3 821862- 300 225 185 211 25.1% 210 209 210 0.95 13.4% 3.2% 92.1% 6.096
067
PDU3-2 821862- 300 530 546 528 64.2% 207 207 207 0.95 13.9% 4.0% 98.6% 2.527
049
7
Opportunity for Transformer Energy Savings in Data Center PDUs
Case Study - June 26, 2008
Projected Energy, Cost and Environmental Savings - YAHOO! Data Center, Santa Clara, CA -
Thirty PDU’s are currently in place at the YAHOO! Data Center. With collected data from three PDU’s being used as an average, the table below lists
Projected Savings and the Environmental contributions that could be realized if Lowest Life Cycle Cost, (DOE CSL-3 Class Efficiency,) were
incorporated facility-wide. Energy cost base $0.12 per kWh.
YAHOO! Data Center, Santa Clara, CA
Aggregated Project Savings with Powersmiths
Peak kW reduction 59kW
Annual kWh reduction 1,026,026kWh
Reduction in Air Conditioning Load 17tons
Cost Analysis (calc)
Energy Cost Escalation (above inflation) 3.0%
Existing Energy Rate (kWh) $0.12
Annual Life Cycle Operating Cost & Savings
Operating Cost 20 years 32 years
Existing Transformer $249,640 $ 9,017,710 $20,571,370
Powersmiths Transformer $119,510 $ 4,317,100 $9,848,250
Savings with Powersmiths $130,130 $ 4,700,610 $10,723,120
Summary of Environmental Benefits
Annual Reduction in Greenhouse Gases (per EPA) Equivalent Units
760 tons of CO2 140 Acres trees planted
2,450 tons of Coal 100 Car Emissions
5,940 kgs of SO2 100 homes heated
2,560 kgs of NOx
** Actual overall savings will be 5-10% higher when the overhead losses incurred by UPS’s, generators
and other distribution equipment, as they have not been included in these calculations.
8
