1 | Building Technologies Program eere.energy.gov 

# Review of the Life

- Cycle Cost and National Impacts Analyses

Katie Coughlin Lawrence Berkeley National Laboratory

Low Voltage Dry

- Type Distribution Transformers Negotiated Rulemaking Working Group Meeting

September 28 , 20112 | Building Technologies Program eere.energy.gov 

# Steps in the Standards Rulemaking

Framework Document Preliminary Analysis NOPR Final Rule Date

Screening Analysis Engineering Analysis

Energy Use and End

- Use Load Characterization Shipments Analysis National Impact Analysis Markups for Equipment Price Determination

Life

- Cycle Cost and Payback Period Analysis Market & Technology Assessment

Preliminary Manufacturer Impact Analysis Compliance Date3 | Building Technologies Program eere.energy.gov 

# • Candidate Standard Levels (CSLs) and Efficiency Levels (ELs) are technically identical

– The name change refers to different stages of the rule

- making process (preliminary vs NOPR)

– CSLs/ELs are defined for each individual design line

– We will use the term Efficiency Levels



# • Trial Standard Levels are defined as a collection of CSLs for all the design lines within a product class 

# Note on Terminology

Analysis Acronym Depends on EL Depends on TSL Engineering

--- No No Life Cycle Cost LCC Yes No National Impacts NIA Yes Yes Manufacturer Impacts MIA Yes Yes4 | Building Technologies Program eere.energy.gov 

# LCC and PBP Analysis

A & B Parameter

Transformer Designs A&B Selection

Markups & T otal

Installed Cost


### LCC Transformer Loading

Electricity Cost & Prices

Electricity Growth & Price Trends

Discount

Rates

Compliance Date, Lifetime Transformer Design Selection

Simulate Load & Price

Discount Rate

Selection Annual Operating Costs

Operating Costs over the Lifetime of the Transformer

Net Present Value of Lifetime Operating Cost From: Engineering Analysis

From: Energy Use and Load Characterization Analysis5 | Building Technologies Program eere.energy.gov 

# • 10,000 transformer installations for each LCC run

• Each installation has an owner and a number of characteristics that belong to the owner or installation

• These characteristics are the same for all efficiency levels

• The LCC loops through a series of calculations for each installation and each EL

– Pick an owner from the sample (4800 C&I buildings)

– Calculate statistical load simulation parameters

– Choose a transformer design

– Calculate the installation cost and annual operating costs

– Calculate the full LCC



# • The effect of the efficiency level specification is to restrict the number of available designs 

# Mechanics of the LCC6 | Building Technologies Program eere.energy.gov 

# • Capacity (representative unit)

• Total installed cost

• Test procedure efficiency rating

• Design features

– Core material

– Ratio of no

- load to load losses

– Weight 

# • Commercial or industrial building

• Population weight

• Geographic location

• Seasonal marginal prices for electricity (kWh and kW)

• Evaluator (yes/no)

• Discount rate

• Monthly loss factor and peak responsibility factor

• Peak load factor

• Lifetime

• Installation constraints 

# Mechanics of the LCC (2)

Transformer Installation7 | Building Technologies Program eere.energy.gov 

## • The LCC does not assume test procedure loadings

• For transformers, efficiency depends on energy losses

– No

- load losses

• Parameterized by loss rate NL

• Occur whenever the transformer is energized

• Annual watt

- hours = 8760*NL

– Load losses

• Parameterized by loss rate LL = load loss at 100% load

• Vary with the square of the load on the transformer

• Load dependence is captured through the loss factor LSF

• A given efficiency can be achieved by a wide range of combinations of
no - load and load loss rates

• The LCC accounts for time

- varying electricity costs

– Operating Cost = ∑ t 

## transformer_loss (t) × electricity_cost (t)

– t is the time period index

– Time period is monthly for dry

- type transformers in buildings 

# Energy Use and the LCC8 | Building Technologies Program eere.energy.gov 

# Example: Cost

- Efficiency data and CSLs for DL7 (75 kVA, 1

- phase)

$500 $1,500 $2,500 $3,500 $4,500 $5,500 $6,500 $7,500 $8,500 $9,500

97.80% 98.00% 98.20% 98.40% 98.60% 98.80% 99.00% 99.20% 99.40% 99.60%Manufacturer Selling Price ($)

Efficiency at 35% Load, Temperature Corrected M12_AlAl_bl_3leg M12_CuAl_bl_3leg M6_AlAl_bl_3leg M6_AlAl_fm_3leg M4_CuAl_fm_3leg M3_AlAl_fm_3leg M3_AlAl_slm_3leg M3_AlAl_dgw_3leg H0_AlAl_fm_3leg H0_AlAl_slm_3leg ZDMH_AlAl_dgw_3leg H0_CuCu_fm_3leg SA1_AlAl_dgw_5leg SA1_CuCu_dgw_5leg CSLs CSL 0 CSL 1 CSL 2 CSL 3 NEMA Pr. CSL 4 CSL 5 CSL 6 CSL 79 | Building Technologies Program eere.energy.gov 

# Transformer Design Selection

Example: DL7, efficiency level 510 | Building Technologies Program eere.energy.gov 

# Transformer Loading

• Loss factors are generated from load factor data and a statistical model

• The average RMS load can be adjusted by setting a sizing parameter (~25%)11 | Building Technologies Program eere.energy.gov 

# Incremental Cost vs. Energy Savings

DL7 LCC Intermediate Results12 | Building Technologies Program eere.energy.gov 

# Example Results: LCC Savings (April 2011) for DL7

Box: 25%

- 75% Whiskers: 5%

- 95%13 | Building Technologies Program eere.energy.gov 

# • Detailed results for the representative units (Design Lines 6 through 8) are extrapolated to full set of kVA ratings

• Use the 0.75 scaling law, with adjustments so that the efficiency vs. kVA curve is continuous at each representative unit

• The NIA generates national

- level results

– Shipments are forecast shipments for each kVa

– Calculate aggregate dollar costs, benefits and energy savings



# • National Impacts are dependent on the combination of ELs that are used to construct a draft TSL

• The NIA results posted Aug. 23 are for a set of draft TSLs which may be modified 

# Mechanics of the NIA14 | Building Technologies Program eere.energy.gov 

# Efficiency vs. kVa15 | Building Technologies Program eere.energy.gov 

# • Low Voltage Dry Type (Design Lines 6

- 8) draft TSLs 

# Summary of Cumulative National Energy Savings Impact (pub. Aug 23)

Design

Line Base (EPACT ‘05) Draft Trial Standard Level

1 2 (NEMA Premium) 3 4 5 6

6 98.00 98.47 98.60 98.60 98.80 98.93 99.44
7 98.00 98.47 98.60 98.60 98.80 98.93 99.44
8 98.60 99.14 99.02 99.25 99.32 99.44 99.58



# • Low Voltage Dry Type (Design Lines 6

- 8) National Impacts

Draft Trial Standard Level

Base 1 2 3 4 5 6

Transformer Shipments 2015

- 2044 (Billion KVA) 0.617 0.668 0.675 0.661 0.667 0.583 0.534
Equipment Cost ($Billions) 17.258 6.020 6.785 5.352 5.941

- 5.449

- 15.930
Operating Cost (Savings in ELs) ($Billions) 23.309 11.937 12.836 12.698 15.456 8.634 13.093

Cumulative Source Savings 2044 (Quads) 1.233 1.326 1.312 1.596 0.895 1.352

Net Present Value at 3% Discount Rate ($Billions) 17.957 19.620 18.051 21.397 3.185

- 2.837

Net Present Value at 7% Discount Rate ($Billions) 6.880 7.558 6.779 7.956

- 0.057

- 4.02416 | Building Technologies Program eere.energy.gov 

# Example Annual Savings and Cost Results (April meeting)

- $2.0 - $1.0 $0.0 $1.0 $2.0 $3.0

2016 2026 2036 2046 2056 2066 2076 2086 2096Billions of 2010 Dollars **Liquid**

**- Immersed** 

**- CSL3** 

- $0.4 - $0.2 $0.0 $0.2 $0.4 $0.6 $0.8 $1.0

2016 2026 2036 2046 2056 2066 2076 2086 2096Billions of 2010 Dollars **Dry**

**- Type** 

**- CSL3**  - $2.0 - $1.0 $0.0 $1.0 $2.0 $3.0 $4.0

2016 2026 2036 2046 2056 2066 2076 2086 2096Billions of 2010 Dollars **All Transformers**

**- CSL3** 

Operating Cost Savings Equipment Cost Net Savings17 | Building Technologies Program eere.energy.gov 

# • National impacts depend on the choice of TSL

– Energy savings

– Net present economic value

– Emissions and social cost of carbon

– Manufacturer impacts

– Demand for new materials



# • Certain TSLs are analyzed for most rule

- making processes

– “Max Tech” required by law

– Maximum NPV (typically the minimum LCC)

– Maximum energy savings with non

- negative LCC



# • Additional TSLs are defined as appropriate

– Technology break

- points

– Fill in gaps in the design spac 

# Analysis Results for draft TSLs18 | Building Technologies Program eere.energy.gov 

# Supplementary slides from the April Public Meeting Extra Slides19 | Building Technologies Program eere.energy.gov 

# • The loss factor estimate is based on the rule

- of

- thumb LSF = k × LF + (1

- k) × LF 2 

# with 0 ≤ k ≤ 1

• This equation is always true for some value of k between zero and one

• Use data to calculate a set of values ( LF, LSF, k ) and estimate a distribution for k 

# Dry

- Type Transformers: Loss Factor Calculations

0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50%

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 parameter kfrequency Low LF Medium LF High LF20 | Building Technologies Program eere.energy.gov 

## • The monthly responsibility factor (RF) defines the contribution of transformer load losses to the building peak demand

• Expect the RF to be correlated to some degree with the load factor LF

– Low load factors imply temporally

- variable loads and less predictable RF

– High load factors imply flat loads and higher, more predictable RF

• Use hourly building data to calculate a set of values ( **LF, RF** ) and define a distribution function that provides the probability of RF given a value for LF 

# Dry

- type Transformers: Responsibility Factor Calculations

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

0.0 0.2 0.4 0.6 0.8 1.0 Load FactorResponsibility Factor21 | Building Technologies Program eere.energy.gov 

## • Energy price projections to 2035 based on EIA/AEO 2010 Reference Case

• AEO High Growth and Low Growth (AEO2010) cases run as a sensitivity

• Electricity price forecasts to 2075 are developed from the average rate of change over the period 2020

- 2035 

# Electricity Price Forecasts

80% 85% 90% 95% 100% 105% 110% 115% 120%

2005 2010 2015 2020 2025 2030 2035Real Price Relative to 2007



# Year Reference Case High Growth Low Growth22 | Building Technologies Program eere.energy.gov 

## • Energy price projections to 2035 based on EIA/AEO 2011 Reference Case 

# Electricity Price Forecasts

80% 85% 90% 95% 100% 105%

2005 2010 2015 2020 2025 2030 2035Real Price Relative to 2008

Year Reference Case High Growth Low Growth23 | Building Technologies Program eere.energy.gov 

# Cost of Conserved Energy (Undiscounted)

Defined as the incremental cost divided by energy savings (no discounting) Compare to the marginal price of electricit y for the installation24 | Building Technologies Program eere.energy.gov 

# Survival and Retirement Functions

Mean Lifetime: 32 years Average: 32 Years

0.0% 0.5% 1.0% 1.5% 2.0% 2.5% 3.0% 3.5% 4.0%

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

0 5 10 15 20 25 30 35 40 45 50 55 60Transformer Retirement Rate (%)Transformer Survival Rate (%) 

### Transformer Reliability Transformer Retirements