1. DOE Final Rule Transformer Efficiency

2. Scope of Final Rule Liquid-filled distribution transformers
HV ratings through 35 kV
LV ratings 600 Volts and below
Single-phase capacities kVA
Three-phase capacities kVA
Dry-type medium-voltage transformer
Approximately same ratings as for liquid-filled

3. Changes: NOPR vs Final Rule
kVA single-phase mandated efficiency slightly less thanTSL5 (was TSL2)
167 kVA single-phase mandated efficiency at TSL4 (was TSL2)
kVA single phase mandated efficiency between TSL2 and TSL3 (was TSL2)

4. Changes: NOPR vs Final Rule
kVA three phase, efficiency levels are TSL2 (unchanged)
kVA three phase mandated efficiency levels at TSL3 or slightly above TSL3

5. Liquid-Filled Efficiency Levels (DOE vs NEMA)
Single Phase
Three Phase
KVA
DOE
NEMA TP-1 15
98.36
98.1 10
98.62
98.4 30
98.76
98.6 45 25
98.91
98.7 75
37.5
99.01
98.8
112.5 50
99.08
98.9
150
99.17
99.0
225
100
99.23
300
167
99.25
99.1
500
250
99.32
99.2
750
333
99.36
1000
99.42
99.3
1500
667
99.46
99.4
2000
833
99.49
2500

6. Liquid-Filled Efficiency Levels
Single Phase
Three Phase
KVA
Efficiency
TSL 15
98.36
=TSL2 10
98.62
<TSL5 30
98.76 45 25
98.91 75
37.5
99.01
112.5 50
99.08
150
99.17
225
100
99.23
300
167
99.25
=TSL4
500
<TSL2
250
99.32
<TSL3
750
>TSL3
333
99.36
1000
=TSL3
99.42
1500
667
99.46
2000
833
99.49
2500

7. Major Concerns—Raw Materials
Most distribution transformers sold today do not meet DOE mandate.
Additional demand on scarce resources…will impact transformer cost and availability
Magnet wire – 55% increased consumption
Strip aluminum – 55% increased consumption
Transformer oil – 3% reduced consumption
Core steel – 25% increased consumption (and 20% decreased core steel vendor capacity)

8. Cost/Efficiency Relationship
100%
Transformer Efficiency

9. Major Concerns—Core Steel
Core Type
Thickness (Mils)
Efficiency
Cost
Amorphous
1.0
Most
Efficient
Costly M2
7.0 M3
9.0 M4
11.0 M5
12.0 M6
14.0
Least

10. Core Grade Distribution, Non-DOE DesignsM4 M3 M5
Production Volume M2 M6
Core Steel Grades

11. Major Concerns—Core Steel
DOE mandate will…
force a shift to M2, M3 and M4 grades
will eliminate usage of M5 and M6 grades for liquid-filled designs

12. Major Concerns—Core Steel
Core steel in global short supply
Domestic suppliers plan no significant capacity increases
Core steel suppliers unable to supply enough M2 and M3 steel
Globally, few core steel suppliers offer M2 and M3 grades
Dry-type transformer producers will consume M5 and M6 grades
Rare and exotic core materials may be required (amorphous metal, laser scribed, high-B, etc.)

13. Transformer Cost
Transformer prices will increase an average 15-30% for aluminum primary designs (depending on product line)
Transformer prices will increase an average 25-40% for non optimum designs (depending on product line)
Increases for individual utilities will vary widely, based on present efficiency levels

14. Other Issues
How will increased pole-type transformer size and weight of 20-25% impact utility retrofits and service reliability?
How will manufacturers handle redesign requirements (most transformer designs do not meet the DOE mandate)?
Will waivers be available for emergencies?

15. Howard Action Plan
Improve process capacities to compensate for increased size and weight
Increase core winding, annealing and lacing capacities
Increase coil winding capacities
Increase coil oven capacities
Increase core/coil oven capacities
Increase crane and conveyor capacities
Expand Laurel Facility size by 525,000 ft2
Increase unit production capacities
Small pole-type from 3,000 to 6,000 units per week
Padmounted capacity by 15%
Modify factory test stations

16. Buy the Lowest TOC That Meets DOE
DESIGN 1
Equal Efficiency
Lower TOC
DESIGN 2
Equal Efficiency
Higher TOC
TOC
TOC
Eff
Eff
Cond
Cond
Core
Core

17. Implementation Schedule
Date
Design / Manufacturing Status
Jan 1, 2008
Re-design process begins
Apr 1, 2009
Start building DOE designs (with existing non-DOE)
Jun 30, 2009
Re-design process completed
Sep 1, 2009
New production started is DOE compliant
Sep 30, 2009
All production completed is DOE compliant
Jan 1, 2010
DOE mandated compliance

18. DOE Contact
Antonio Bousa: Project Manager for Distribution Transformer Energy Conservation Standards, (202)
DOE Web:
Howard Web: