Title: CEE Industry Partners Meeting St. Louis, MO Distribution Transformers: Charting a Course to Achieve
1CEE Industry Partners MeetingSt. Louis, MO
Distribution Transformers Charting a Course to
Achieve Additional Energy Savings
- Ted Jones
- Sr. Industrial Program Manager
- Wednesday, September 26, 2007
2Todays Agenda
- Background on CEE Distribution Transformers
Initiative - Overview of CEE Subcommittee Findings
- Program Perspective
- BPA
- Discussion/Next Steps
3Which Distribution Transformers?
4CEEs CI High-Efficiency Distribution
Transformer Initiative
- Launched in 1998, serves as a platform for
programs to build demand for more efficient
transformers in the commercial and industrial
sector. - The initiative consists of four key components
- A voluntary low voltage transformer efficiency
performance specification - Guidelines for using cost-of-ownership methods in
transformer purchases - Awareness building
- Incentives (where possible)
- Energy Star began labeling low-voltage
transformers soon afterwards.
5CEEs CI High-Efficiency Distribution
Transformer Initiative
- For the commodity type, low-voltage market, the
Initiatives strategy is to create a clear
definition of efficiency (equivalent to NEMA TP
1) and to promote the value in specifying
equipment meeting this definition. - Since the medium voltage equipment is provided on
a build-to-order basis, emphasis is placed on
education regarding the opportunity and method
for cost-of-ownership evaluation rather than
promoting the NEMA specification.
6Background
- The Energy Policy Act of 2005 (EPAct 2005)
established federal minimum standards for
low-voltage, dry-type distribution transformers
which went into effect on January 1, 2007. - New standards are equivalent to the NEMA
specifications supported by CEE and ENERGY STAR
on a voluntary basis since 1998. - During the last few months of 2006 and early in
2007, a CEE subcommittee met to explore the
development of specifications for dry-type, low
voltage transformers based on the analysis
developed by DOE during a transformer rulemaking
process.
7Subcommittee Review of DOE Analysis
- DOE analyzed several designs which were modeled
to represent the full range of products on the
transformer market. Three of the design lines
represent the types of transformers addressed in
CEEs CI Distribution Transformers Initiative,
including - Design Line 6 - Single-phase, Low-Voltage,
Dry-type Units from 15 to 333kVA. The
representative unit for this design line 25kVA - Design Line 7 - Three-phase, Low-Voltage,
Dry-type Units from 15 to 150kVA. The
representative unit for this design line 75kVA. - Design Line 8 - Three-phase, Low-Voltage,
Dry-type Units from 225 to 1000kVA. The
representative unit for this design line 300kVA.
8Technology
- Transformers consist of two primary components
- a core constructed of specialized steel,
- windings typically constructed of copper or
aluminum. - The composition of the core determines the
no-load losses. These losses are relatively
unchanged with the load of the transformer.
- Given that most transformers are lightly loaded
most of the time (35 percent or less), core and
construction techniques factor more heavily with
unit efficiency because they influence no-load
losses.
9Transformer Loading
10Opportunities for Savings
- Because of the relatively low loading of this
class of transformers, the most direct way to
reduce losses is by reducing core losses. This
can be accomplished by - Better construction techniques such as stacked
buttlap (most common, less efficient) to stacked
full miter joints (less common, more efficient). - Thinner laminations of higher quality more
expensive steel.
11DOE Assessment of Savings
- A computer analysis using over 4,000 combinations
of design and materials yielded a scatter plot of
efficiency versus predicted price (DOE, 2005,
page 5-56). For Design Line 7, the analysis
shows many combinations can exceed the current
TP-1 specification of 98 with most advanced
designs falling between 98 and 99 efficiency.
12(No Transcript)
13DOE Candidate Standard Levels
- For each representative unit, DOE calculated both
life-cycle cost (LCC) and LCC savings from a
base-case scenario. DOE then selected six
candidate standard levels for review that
correspond to the following - NEMA TP 1-2002
- 1/3 of the efficiency difference between TP 1 and
the minimum LCC scenario - 2/3 of the efficiency difference between TP 1 and
the minimum LCC scenario - the minimum LCC scenario
- maximum energy savings with no change in LCC
- maximum technologically feasible level
14Subcommittee Assessment
- The CEE sub-committee
- Examined the DOE candidate standard levels and
the LCC performance data for each of the three
representative units (design lines 6, 7, 8)
relevant to the CEE Initiative - Extrapolated those values to the other KVA sizes
included under the CEE Initiative - Investigated the availability of distribution
transformers with energy performance above the
new federal minimum standard (NEMA TP 1, DOE
Level 1) to see how they compared to the higher
candidate standard levels identified by DOE.
15Subcommittee Findings
- Review of catalogs found highest efficiency
products meeting coming very close to DOE Level
2. - Moderate savings can be achieved at relatively
low cost with some instances at no incremental
cost . - It was noted that three kVA ratings represent
nearly 70 of the three phase market and 80 of
the single phase market.
16Est. Annual Energy Savings Compared to the
Current Standard for Three Phase Transformers
(kWh)
17Est. Annual Energy Savings Compared to the
Current Standard for Single Phase Transformers
(kWh)
18Conclusions
- Lack of transformers on the market today with
energy performance exceeding the current federal
minimum standard is preventing customers from
benefiting from the savings potential
demonstrated by DOE - By working together through the CEE Distribution
Transformers Initiative could efficiency programs
could play role in bringing these products to
market. - CEE should continue the Initiatives fundamental
strategy to support demand for more efficient
transformers.
19Next Steps
- Subcommittee recommended adopting the DOE Level 2
specification as the new CEE level of
performance. - This approach would provide a consistent
definition for all market actors and reward the
manufacturers that have products exceeding
current federal minimum standards. Products at
this level of performance are currently available
at low or no incremental cost and would become
more available in the market over time with
program support. - Consider DOE Level 4 as a stretch goal.
- The DOE analysis demonstrates that
super-efficient distribution transformers meeting
DOE Level 4 are feasible technologically and
economically justified but would require
significant investment on the part of
manufacturers to bring them to market. The
subcommittee recommended program support for DOE
Level 4 efficiency levels and advised getting
manufacturer input on the opportunity to bring
these products to market.
20Discussion
21Member Perspective