This document discusses the need to improve transformer efficiency standards beyond the EPACT 2005 levels. It provides facts about transformer lifespan compared to other building equipment and shows that transformers represent a small fraction of building costs. Several studies are referenced that show transformers in buildings are often lightly loaded. The document advocates moving efficiency standards from a single minimum level to a system of multiple classes better matched to actual loading profiles. Higher efficiency transformers are shown to reduce losses and operating costs significantly compared to current EPACT/TP1 standards, especially under real-world electronic loads.

1. The Need to
Take
Transformers
beyond
EPACT 2005
The Need to
Take
Transformers
beyond
EPACT 2005

2. Founded in 1996Founded in 1996
Power Quality & Energy EfficiencyPower Quality & Energy Efficiency
•• ISO 14001 environmental management systemISO 14001 environmental management system
•• First to meet proposed DOE Efficiency Class 3First to meet proposed DOE Efficiency Class 3
•• Education for Sustainability ToolsEducation for Sustainability Tools
•• Participate in Sustainability Oriented OrganizationsParticipate in Sustainability Oriented Organizations

3. FACTS: Transformer vs. Life Cycle CostFACTS: Transformer vs. Life Cycle Cost
Few Products, if any, will remain functionalFew Products, if any, will remain functional
longer than transformers, 35longer than transformers, 35 –– 40+ years40+ years
Lighting Comparison 2Lighting Comparison 2 -- 3 X3 X
HVAC Comparison 1HVAC Comparison 1 -- 2 X2 X
Low Voltage Transformers represent lessLow Voltage Transformers represent less
than ½ of 1% Building Costthan ½ of 1% Building Cost

5. Transformer Loading ????Transformer Loading ????

6. Cadmus Study documents lightly loaded transformers in
many applications
Cadmus Study documents lightly loaded transformers inCadmus Study documents lightly loaded transformers in
many applicationsmany applications
Metered Load Factors for LowMetered Load Factors for Low--Voltage, DryVoltage, Dry--Type Transformers in Commercial,Type Transformers in Commercial,
Industrial and Public BuildingsIndustrial and Public Buildings
The Cadmus Group Inc. 12/7/99, Prepared for Northeast Energy EfThe Cadmus Group Inc. 12/7/99, Prepared for Northeast Energy Efficiency Partnershipficiency Partnership
Figure ES-4
RMS Average Transformer Loads by Building Type
0%
5%
10%
15%
20%
25%
30% O
fffice
M
anufacturing
R
etail
Schools
H
ealthcare
RMSAverageLoadFactor

7. 45kVA Efficiency Comparisons vs. Field Data & TP-1
95%
96%
97%
98%
99%
0
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
% loading
%Efficiency
0
10
20
30
40
50
60
#transformers
Field Load Data TP1
TP-1, 35%
High Performance vs. TP1 (EPACT 2005)
transformer (Linear Loading Efficiency)
High Performance vs. TP1 (EPACT 2005)
transformer (Linear Loading Efficiency)
EPACT & TP1 have single 35% performance point not matched to loaEPACT & TP1 have single 35% performance point not matched to load profiled profile
XX

8. From minimum
Efficiency to
Life Cycle
From minimum
Efficiency to
Life Cycle
NEMA TP1 as minimumNEMA TP1 as minimum
efficiencyefficiency –– to rid market ofto rid market of
worst offendersworst offenders
Significant losses remainSignificant losses remain
5 efficiency classes5 efficiency classes
Finds low life cycle cost to beFinds low life cycle cost to be
proposed Class Level 3proposed Class Level 3
KK--RATED TRANSFORMERS ARERATED TRANSFORMERS ARE
NO LONGER EXEMPTNO LONGER EXEMPT

9. Moving to Life Cycle AssessmentMoving to Life Cycle Assessment
75kVA Efficiency Losses
Operating Cost
Reduction
Class 1 (EPACT) 98.00% 2.0% 0%
Class 2 98.30% 1.70% 15.0%
Class 3 98.60% 1.40% 30.0%
Class 4 98.90% 1.10% 45.0%
Class 5 99.09% 0.91% 54.5%
LowLow
LifeLife
CycleCycle
CostCost
D O E P r o p o s e d E f f ic ie n c y C la s s e s
( e x a m p le : 7 5 k V A 4 8 0 /2 0 8 - 1 2 0 V d r y t y p e )
9 8 . 0 0 %
9 8 . 2 0 %
9 8 . 4 0 %
9 8 . 6 0 %
9 8 . 8 0 %
9 9 . 0 0 %
9 9 . 2 0 %
C la s s 1 C la s s 2 C la s s 3 C la s s 4 C la s s 5
1 5 % le s s
lo s s e s
3 0 %
le s s
lo s s e s
4 5 %
le s s
lo s s e s
5 4 .5 %
le s s
lo s s e s
E P A C T /T P 1
m in . le g a l

11. Comparing Efficiency ClassesComparing Efficiency Classes
BEFORE/AFTER Demand Efficiency 45kVA
65
75
85
95
- 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00
% loading
Efficiency(%)
Powersmiths C-3
95.6%
Square D
K4, TP1
88.0%
GE (Pre-TP-1) Original 79.6%

12. Comparing LossesComparing Losses
BEFORE/AFTER Sys_DemLoss 45kVA
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
- 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00
% loading
kWlosses
Square D K4, TP1
223 W
Original GE 45kVA
418 W
E-SAVER-C3L
74 W

13. Detailed dataDetailed data

15. Things to remember about
transformers
- electronics are everywhere
Things to remember about
transformers
- electronics are everywhere
Electrical systems deliver
optimum performance
when feeding continuous
“linear” loads:
• motors
• incandescent lighting
• resistive heating
Electronics are everywhere
- computers, lab, diagnostic & operating
equipment, & patient care
Variable Speed Drives run Ventilation System

16. 15kVA TP1 transformer Performance Comparison
Ideal factory test profile (Linear) vs. Real World Electronic Loading
90
91
92
93
94
95
96
97
98
99
100
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140
Linear Load
Electronic Load
X

17. High Performance vs. TP1 (EPACT 2005)
transformer (Non-Linear Loading Efficiency)
High Performance vs. TP1 (EPACT 2005)
transformer (Non-Linear Loading Efficiency)
SAVINGSSAVINGS
75kVA Efficiency Comparisons vs. Field Data & TP-1
91%
93%
95%
97%
99% 0
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
% loading
%Efficiency
0
10
20
30
40
50
60
#transformers
Pow ersmiths Field Data
Standard 150C
Pow ersmiths ESAVER-
C3
TP-1, 35%
TP1 Transformer
EE--saver vs. TPsaver vs. TP--1 Efficiency comparison under real1 Efficiency comparison under real--world loadworld load

18. High Performance Green
Buildings
High Performance Green
Buildings