CHAPTER 14. UTILITY IMPACT ANALYSIS

TABLE OF CONTENTS

14.1 INTRODUCTION

............................................................................................................ 14­1

14.2 ASSUMPTIONS AND METHODOLOGY..................................................................... 14­1

14.3 RESULTS

......................................................................................................................... 14­3

14.3.1 Impacts Related to Commercial Refrigeration Equipment – TSL 1.................. 14­6

14.3.2 Results for TSL 2 through TSL 5

...................................................................... 14­8

LIST OF TABLES

Table 14.3.1 Reference Case Forecast: Commercial Electricity Consumption,

Electricity Generation, and Electricity Capacity

............................................... 14­3

Table 14.3.2 TSL 1 Utility Impacts for Commercial Refrigeration Equipment..................... 14­4

Table 14.3.3 TSL 2 Utility Impacts for Commercial Refrigeration Equipment..................... 14­4

Table 14.3.4 TSL 3 Utility Impacts for Commercial Refrigeration Equipment..................... 14­5

Table 14.3.5 TSL 4 Utility Impacts for Commercial Refrigeration Equipment..................... 14­5

Table 14.3.6 TSL 5 Utility Impacts for Commercial Refrigeration Equipment..................... 14­6

14­iCHAPTER 14. UTILITY IMPACT ANALYSIS

14.1 INTRODUCTION

The U.S. Department of Energy (DOE) analyzed the effects of amended energy

conservation standards for commercial refrigeration equipment (CRE) on the electric utility

industry. DOE conducted the utility impact analysis using Energy Information Administration

(EIA)’s National Energy Modeling System (NEMS). a NEMS is a public domain, multi­sectoral,

partial equilibrium model of the U.S. energy sector. Each year, DOE/EIA uses NEMS to

produce a reference energy forecast for the United States, published in the Annual Energy

Outlook

. 1 The Annual Energy Outlook for 2007 ( AEO2007) forecasts energy supply and demand

through 2030.

DOE used a variant of this NEMS model, referred to as NEMS­BT, b to account for the

impact of amended energy conservation standards on the reference energy forecast. The

NEMS­BT reference case was modeled after the AEO2007 reference case. c The utility impact

analysis consists of a comparison between model results for the reference case and for the policy

cases in which amended energy conservation standards are in place. d

NEMS­BT has several advantages that have led to its use in the analysis of national

energy conservation standards. The model uses a set of assumptions that are well known and

fairly transparent, due to the exposure and scrutiny each AEO receives. In addition, the

comprehensiveness of NEMS­BT permits the modeling of interactions among the various energy

supply and demand sectors, and the economy as a whole, producing a complete picture of the

effects of energy conservation standards. Perhaps most importantly, NEMS­BT can be used to

estimate marginal effects, which yield a more accurate estimate of the actual impacts of energy

conservation standards compared to considering only average effects.

14.2 ASSUMPTIONS AND METHODOLOGY

DOE’s utility impact analysis applies the same basic set of assumptions as the AEO2007

. For example, the operating characteristics (energy conversion efficiency, emissions rates) of future

electricity generating plants are as specified in the AEO2007 Reference Case. The utility impact

a For more information on NEMS, refer to the U.S. Department of Energy, Energy Information Administration

documentation. A useful summary is National Energy Modeling System: An Overview 2003

, DOE/EIA0581(2003), March 2003. More detailed and more current documentation of various sub­models within NEMS can

be obtained from EIA’s website: http://www.eia.doe.gov/oiaf/forecasting.html.

b DOE/EIA approves the use of NEMS to describe only an official version of the model without any modification to

code or data. Because this analysis entails some minor code modifications and the model is run under various policy

scenarios that are variations of DOE/EIA assumptions, DOE refers to it by the name NEMS­BT (BT is DOE’s

Buildings Technologies Program, under whose aegis this work has been performed).

c The NEMS­BT reference case shows very slight differences from the AEO reference case. In 2030, total

commercial electricity consumption in the NEMS­BT reference case was 0.08 percent lower than the 2007 AEO

reference case. For total electricity generation and total installed generating capacity, NEMS­BT produced

estimates that were 0.04 percent and 0.05 percent lower than the AEO reference case, respectively. In the remainder

of this chapter, the “reference case” refers to the NEMS­BT reference case.

d In the discussion below, the abbreviated term “the reference case” should be understood to refer to the AEO 2007

Reference Case.

14­1analysis reports the changes in installed capacity and generation, by fuel type, that results from

each trial standard level (TSL) as well as changes in electricity sales to the commercial sector.

The utility analysis uses the AEO2007 Reference Case as the base case and treats the

energy conservation standards on commercial refrigeration equipment as variations in policy.

The effect of the policy is calculated as the difference in the reference case and the proposed

energy conservation standards case. Because the implementation of energy conservation

standards for commercial refrigeration equipment reduces the electricity demand by less than

one­tenth of a percent (in the range of 0.01 to 0.06 percent in 2025, depending on the TSL) in

any given year, its effect is difficult to adequately measure in the NEMS simulations. Therefore,

larger reductions in demand are modeled, and results for the TSLs are interpolated. The effects

are assumed to be linear within the range of interpolation.

In its analysis of energy conservation standards for commercial refrigeration equipment,

DOE adjusted the annual end­use energy consumption for refrigeration that was predicted within

the commercial sector module of NEMS­BT. These decrements in the annual consumption were

made for each census division using the method for computing energy savings developed in the

national impact analysis (see Chapter 11). The changes in annual consumption were translated

into changes in hourly system load as part of the normal NEMS modeling process using the

NEMS’ standard commercial building refrigeration shapes.

As mentioned above, the magnitude of the energy decrement that would be required for

NEMS­BT to produce stable results, outside the range of numerical noise, is larger than the

highest energy conservation standard under consideration. e Therefore, DOE estimated results

corresponding to the TSL using interpolation. It implemented reductions to both the commercial

refrigeration end use at multiples of the proposed standards, and linearly interpolated actual

changes in generation and capacity due to the standard from these outputs. Compared to the total

savings for all commercial refrigeration equipment under Trial Standard Level 2, the multipliers

used in this analysis were 2.7, 5.4, and 8.2. Appendix J provides details of the interpolation

method and how the multiples were selected.

The terminal year of the NEMS­BT model is 2030. Impacts beyond 2030 were

extrapolated based on the pattern of electricity savings (in kWh) expected for a particular

standard. The extrapolation was based on a comparison of the change in the NEMS­BT variable

(e.g., coal­fired generation) to the change in electricity savings over the period 2025 to 2030. As

first step to implement the method, the changes in electricity savings over three periods—2030 to

2035, 2035 to 2040, and 2040 to 2042—were expressed as ratios to the change in electricity

savings over the period 2025 to 2030. The changes in a utility­sector variable were then

multiplied by these ratios to estimate the changes in the periods after 2030.

To illustrate the approach, the NEMS­BT results for TSL 3 indicate a reduction in

electricity generation for coal plants (relative to the NEMS­BT reference case) of 2.16 TWh

terawatt­hours (TWh) in 2025 and 2.71 TWh in 2030. The 5­year reduction of coal­fired

generation is 0.41 TWh. From the National Energy Savings Model (NES) (described in

e The numerical noise stems, in part, from the fact that a precise balancing between the demand and supply sides of

NEMS is not always achieved, given the iterative nature of the solution process.

14­2Chapter 11 of the TSD), the change in electricity savings from 2030 to 2035 is about 88 percent

of that for 2025 to 2030. Thus, the change in coal generation between 2030 and 2035 is

calculated to be (0.88) x (0.41) TWh or 0.36 TWh. Thus, the extrapolated value of the reduction

in coal generation compared to the reference case for 2035 is (2.71) + (0.36), or 2.97 TWh.

14.3 RESULTS

The results from the reference case are shown in Table 14.3.1. Results for the various

TSLs are presented in Table 14.3.2 through Table 14.3.6. Each table shows forecasts using

interpolated results, as described in section 14.2, for commercial sector energy sales, total U.S.

electricity generation, and installed capacity.

Table 14.3.1 Reference Case Forecast: Commercial Electricity Consumption, Electricity

Generation, and Electricity Capacity

NEMS-BT Results:

* 2005 2010 2015 2020 2025 2030

* * Commercial Sector Electricity Consumption

Electricity Sales (TWh) 1,266 1,399 1,548 1,694 1,863 2,060

Total U.S. Electricity Generation †

Coal (TWh) 2,015 2,145 2,290 2,495 2,880 3,313

Petroleum (TWh) 122 95 103 103 105 107

Gas (TWh) 756 895 1,023 1,056 1,008 940

Nuclear (TWh) 780 789 816 886 890 909

Renewables (TWh) 362 467 488 498 511 527

Total (TWh) 4,035 4,392 4,720 5,037 5,395 5,795

Installed Generating Capacity ‡

Fossil Steam (GW) 431.9 440.3 412.5 438.4 482.1 534.4

Combined Cycle (GW) 176.6 193.3 195.4 202.5 209.8 210.8

Combustion Turbines (GW) 133.2 137.0 120.6 126.9 136.3 156.8

Nuclear (GW) 100.0 100.5 103.0 111.7 112.3 114.3

Renewables (GW) 118.3 126.6 128.3 130.3 134.9 142.0

Total (GW) 960.1 997.8 959.9 1,009.8 1,075.4 1,158.4

* Values for 2005 are reported by NEMS­BT, but are very close to the historical values shown in various tables in EIA's

Annual Energy Review 2005

** Comparable to Table A8 of AEO2007: Electricity Supply, Disposition, Prices, and Emissions Includes generation from

electricity ­only, combined heat and power, and end­use generators

† Comparable to Table A9 of AEO2007: Electricity Generating Capacity

‡ Includes coal steam and other fossil fuel steam plants

14­3Table 14.3.2 TSL 1 Utility Impacts for Commercial Refrigeration Equipment

NEMS-BT Results: Difference from Reference Case

Extrapolation

2015 2020 2025 2030 2035 2040 2042

Commercial Sector Electricity Consumption

Electricity Sales (TWh) ­0.197 ­0.413 ­0.597 ­0.748 ­0.882 ­1.055 ­1.137

Total U.S. Electricity Generation

Coal (TWh) ­0.126 ­0.300 ­0.426 ­0.507 ­0.578 ­0.670 ­0.714

Petroleum (TWh) 0.004 0.009 0.010 0.008 0.005 0.003 0.001

Gas (TWh) ­0.065 ­0.108 ­0.068 0.055 0.163 0.303 0.369

Nuclear (TWh) 0.029 ­0.008 ­0.151 ­0.401 ­0.622 ­0.908 ­1.044

Renewables (TWh) ­0.016 ­0.020 0.004 0.055 0.100 0.158 0.186

Total (TWh) ­0.174 ­0.426 ­0.632 ­0.792 ­0.932 ­1.115 ­1.202

Installed Generating Capacity

Fossil Steam (GW) ­0.032 ­0.062 ­0.069 ­0.058 ­0.048 ­0.035 ­0.029

Combined Cycle (GW) 0.003 0.006 0.006 0.004 0.003 0.001 0.000

Combustion Turbines

(GW) 0.010 0.022 0.030 0.035 0.040 0.046 0.049

Nuclear (GW) 0.004 ­0.002 ­0.019 ­0.045 ­0.067 ­0.097 ­0.111

Renewables (GW) 0.002 0.002 ­0.001 ­0.006 ­0.010 ­0.015 ­0.018

Total (GW) ­0.014 ­0.034 ­0.053 ­0.068 ­0.082 ­0.100 ­0.109

Table 14.3.3 TSL 2 Utility Impacts for Commercial Refrigeration Equipment

NEMS-BT Results: Difference from Reference Case

Extrapolation

2015 2020 2025 2030 2035 2040 2042

Commercial Sector Electricity Consumption

Electricity Sales (TWh) ­0.760 ­1.597 ­2.307 ­2.891 ­3.407 ­4.077 ­4.394

Total U.S. Electricity Generation

Coal (TWh) ­0.488 ­1.158 ­1.648 ­1.959 ­2.233 ­2.590 ­2.759

Petroleum (TWh) 0.017 0.035 0.039 0.029 0.021 0.010 0.005

Gas (TWh) ­0.252 ­0.416 ­0.262 0.211 0.628 1.170 1.427

Nuclear (TWh) 0.112 ­0.031 ­0.585 ­1.551 ­2.403 ­3.510 ­4.035

Renewables (TWh) ­0.060 ­0.076 0.014 0.211 0.385 0.610 0.717

Total (TWh) ­0.671 ­1.647 ­2.443 ­3.059 ­3.603 ­4.310 ­4.645

Installed Generating Capacity

Fossil Steam (GW) ­0.124 ­0.241 ­0.266 ­0.223 ­0.185 ­0.136 ­0.112

Combined Cycle (GW) 0.012 0.022 0.023 0.017 0.011 0.004 0.001

Combustion Turbines

(GW) 0.037 0.085 0.117 0.137 0.155 0.178 0.188

Nuclear (GW) 0.016 ­0.006 ­0.074 ­0.173 ­0.261 ­0.375 ­0.429

Renewables (GW) 0.007 0.007 ­0.004 ­0.022 ­0.038 ­0.059 ­0.069

Total (GW) ­0.053 ­0.133 ­0.203 ­0.264 ­0.318 ­0.388 ­0.421

14­4Table 14.3.4 TSL 3 Utility Impacts for Commercial Refrigeration Equipment

NEMS-BT Results: Difference from Reference Case

Extrapolation

2015 2020 2025 2030 2035 2040 2042

Commercial Sector Electricity Consumption

Electricity Sales (TWh) ­0.998 ­2.096 ­3.028 ­3.794 ­4.471 ­5.350 ­5.766

Total U.S. Electricity Generation

Coal (TWh) ­0.640 ­1.519 ­2.163 ­2.571 ­2.931 ­3.399 ­3.620

Petroleum (TWh) 0.022 0.045 0.051 0.038 0.027 0.013 0.006

Gas (TWh) ­0.330 ­0.546 ­0.344 0.277 0.824 1.536 1.873

Nuclear (TWh) 0.147 ­0.041 ­0.768 ­2.035 ­3.154 ­4.607 ­5.295

Renewables (TWh) ­0.079 ­0.100 0.019 0.277 0.505 0.801 0.941

Total (TWh) ­0.881 ­2.161 ­3.206 ­4.015 ­4.729 ­5.656 ­6.096

Installed Generating Capacity

Fossil Steam (GW) ­0.163 ­0.316 ­0.350 ­0.293 ­0.243 ­0.178 ­0.147

Combined Cycle (GW) 0.016 0.030 0.031 0.022 0.015 0.005 0.001

Combustion Turbines

(GW) 0.049 0.111 0.154 0.180 0.203 0.233 0.247

Nuclear (GW) 0.021 ­0.008 ­0.097 ­0.227 ­0.342 ­0.492 ­0.563

Renewables (GW) 0.009 0.009 ­0.005 ­0.029 ­0.050 ­0.078 ­0.091

Total (GW) ­0.069 ­0.174 ­0.267 ­0.347 ­0.417 ­0.509 ­0.552

Table 14.3.5 TSL 4 Utility Impacts for Commercial Refrigeration Equipment

NEMS-BT Results: Difference from Reference Case

Extrapolation

2015 2020 2025 2030 2035 2040 2042

Commercial Sector Electricity Consumption

Electricity Sales (TWh) ­1.161 ­2.439 ­3.525 ­4.417 ­5.205 ­6.228 ­6.712

Total U.S. Electricity Generation

Coal (TWh) ­0.745 ­1.769 ­2.518 ­2.993 ­3.412 ­3.956 ­4.214

Petroleum (TWh) 0.026 0.053 0.059 0.044 0.032 0.015 0.007

Gas (TWh) ­0.384 ­0.636 ­0.400 0.322 0.960 1.788 2.180

Nuclear (TWh) 0.171 ­0.048 ­0.894 ­2.369 ­3.671 ­5.362 ­6.164

Renewables (TWh) ­0.092 ­0.117 0.022 0.322 0.588 0.932 1.095

Total (TWh) ­1.026 ­2.516 ­3.731 ­4.673 ­5.504 ­6.584 ­7.096

Installed Generating Capacity

Fossil Steam (GW) ­0.190 ­0.368 ­0.407 ­0.341 ­0.283 ­0.207 ­0.172

Combined Cycle (GW) 0.018 0.034 0.036 0.026 0.017 0.006 0.001

Combustion Turbines

(GW) 0.057 0.130 0.179 0.210 0.236 0.271 0.288

Nuclear (GW) 0.024 ­0.009 ­0.112 ­0.264 ­0.398 ­0.572 ­0.655

Renewables (GW) 0.010 0.010 ­0.006 ­0.034 ­0.058 ­0.090 ­0.105

Total (GW) ­0.081 ­0.203 ­0.311 ­0.404 ­0.486 ­0.592 ­0.643

14­5Table 14.3.6 TSL 5 Utility Impacts for Commercial Refrigeration Equipment

NEMS-BT Results: Difference from Reference Case

Extrapolation

2015 2020 2025 2030 2035 2040 2042

Commercial Sector Electricity Consumption

Electricity Sales (TWh) ­1.687 ­3.543 ­5.119 ­6.415 ­7.559 ­9.045 ­9.749

Total U.S. Electricity Generation

Coal (TWh) ­1.083 ­2.569 ­3.657 ­4.346 ­4.955 ­5.746 ­6.121

Petroleum (TWh) 0.038 0.077 0.086 0.065 0.046 0.022 0.010

Gas (TWh) ­0.558 ­0.923 ­0.581 0.468 1.394 2.597 3.166

Nuclear (TWh) 0.248 ­0.069 ­1.299 ­3.441 ­5.332 ­7.789 ­8.952

Renewables (TWh) ­0.134 ­0.169 0.031 0.468 0.853 1.354 1.591

Total (TWh) ­1.490 ­3.654 ­5.420 ­6.787 ­7.995 ­9.563 ­10.306

Installed Generating Capacity

Fossil Steam (GW) ­0.276 ­0.534 ­0.591 ­0.495 ­0.411 ­0.301 ­0.249

Combined Cycle (GW) 0.027 0.050 0.052 0.038 0.025 0.009 0.002

Combustion Turbines

(GW) 0.083 0.188 0.260 0.304 0.343 0.394 0.418

Nuclear (GW) 0.035 ­0.013 ­0.163 ­0.384 ­0.579 ­0.831 ­0.951

Renewables (GW) 0.015 0.015 ­0.009 ­0.049 ­0.085 ­0.131 ­0.153

Total (GW) ­0.117 ­0.295 ­0.451 ­0.586 ­0.706 ­0.861 ­0.934

14.3.1 Impacts Related to Commercial Refrigeration Equipment

– TSL 1

Table 14.3.2 shows the impacts for all commercial refrigeration equipment under the

Trial Standard Level 1 (TSL 1). The top line of Table 14.3.2 shows that under TSL 1, total

commercial electricity use in terawatt­hours (TWh) declines by 0.20 TWh in 2015 and by

0.75 TWh in 2030.

The reductions in total commercial electricity generation (shown as the last line in the

second panel of the table) are slightly different than the reductions in commercial electricity use

(shown in the first line of the table). These differences are to due to the net impact of various

factors at the energy system level. The NEMS model suggests that electricity prices generally

decline slightly following the implementation of the standard. These price changes lead to very

small increases in demand for all major end­use sectors (residential, industrial, as well as

commercial f ). An offsetting factor at the system level, however, is that some changes in

generation also reflect transmission and distribution losses that respond to higher or lower sales

to end users. By 2030, the net effect of these factors indicates that the change in total electricity

generation (­0.79 TWh) is somewhat higher than the savings in the commercial sector alone.

As expected, total generation falls in a nearly continuous fashion with respect to the

lower electricity demand prompted by the energy conservation standard. However, for the

individual generation technologies by fuel type, the responses are much more varied. In the long

f Specifically, in the NEMS­BT commercial sector model, the response to higher electricity prices is modeled in

two ways. First, the selection of more efficient equipment is prompted when new buildings are constructed or when

equipment is replaced in existing buildings. Second, a general behavioral response to higher prices is modeled via a

price elasticity in which a percentage increase in prices (x) is reflected by a different percentage reduction in

consumption (y). For most commercial end uses, this price elasticity (y/x) is approximately ­0.15.

14­6term (e.g., by 2030), the NEMS­BT model suggests that there may be significant changes,

compared to the reference case

, between plants serving primarily base load uses (principally

coal, and nuclear) and plants using other fuels. The CRE energy conservation standards

generally reduces base load (and thus off­peak) electricity demand. This change in the load

profile reduces the attractiveness of coal and nuclear plants. This change also suggests some

increase in generation by plants using natural gas and renewables, especially in the years after

2025.

In the near term (through 2020), the NEMS­BT model suggests slightly different

behavior. Electricity generation from natural gas plants is somewhat lower than that in the

reference case. Nuclear generation is relatively unchanged, reflecting the inability of that

segment of the industry to adjust quickly to changes in demand. In general, because there is less

opportunity over the next decade (through 2020) to build new plants and optimize the electricity

supply system to meet the altered character of the load, other institutional and economic factors

may be more relevant in how various generating facilities are dispatched.

The bottom panel of results in Table 14.3.2 shows the impacts on generating capacity by

type of generation technology. Total generation capacity is lower by about 0.07 gigawatts (GW)

in 2030, roughly a 0.05 percent decline from the reference case.

The components of total capacity are distinguished by type of generation technology

rather than strictly by fuel type. Fossil fuel steam plants are primarily coal­fired, but also include

some petroleum use. High efficiency, combined­cycle plants and combustion turbines both use

natural gas.

Because coal and nuclear plants are primarily used to meet base loads, the capacity of

these types of plants shows the greatest decline over the next two decades. Compared to the

Reference Case, the total generation capacity of coal plants declines (relative to the reference

case) throughout the forecast period and is lower by about 0.06 GW by 2030. Nuclear capacity

in 2030 is lower than the reference case by about 0.05 GW in 2030.

Consistent with the pattern shown for generation from natural gas in 2030, combined

cycle and combustion turbine capacity is significantly higher than the Reference Case. Because

the overall load profile shows a higher percentage of weather­related electricity consumption,

combustion turbine capacity in 2030 is about 0.04 GW higher than the Reference Case.

Generation capacity from renewables declines very slightly. Comparing this result to the slightly

positive impact on generation from renewables in 2030, the model suggests that overall capacity

utilization from these technologies increases. g

g Any comparison between the generation and capacity impacts shown in the table is complicated by the fact that

various types of generating plants operate for different numbers of hours during the year. Base load plants such as

fossil fuel steam and nuclear are relatively comparable as they operate for roughly the same number of hours during

the year. Because renewables comprise a number of technologies with various operating hours, it is not surprising

to see a divergence between the behavior of generation and capacity at this aggregate level.

14­714.3.2 Results for TSL 2 through TSL 5

Table 14.3.3 through Table 14.3.6 show the estimated impacts for Trial Standard Levels

2 through 5. Table 14.3.4, corresponding to Trial Standard Level 3, shows the impacts

associated with energy conservation standards selected to match minimum life­cycle cost levels

for each type of refrigeration equipment. As shown in this table, compared to the Reference

Case, total generation in 2030 would decline by about 4 TWh. The major reductions in

generation occur in coal and nuclear plants. Total generation capacity falls by 0.35 GW relative

to the reference case or about 0.03%.

Table 14.3.5 shows impacts under Trial Standard Level 4 for all CRE products

considered in this rulemaking. Trial Standard Level 4 corresponds to a case in which for the

majority of products the standards are set at the maximum (technologically feasible) level. For

five products (as cited in Chapter 9), the levels are set at the minimum life­cycle cost level

identical to those in Trial Standard Level 3. In this mixed case, the 2030 impact on total

generation is about 15 percent greater than that for TSL 3. Total capacity is lower about 0.4 GW

compared to the Reference Case.

In Trial Standard Level 5 the standards for all products are set to the maximum

(technologically feasible) level. The impacts from this case are shown in Table 14.3.6. In this

case, the 2030 impact on total generation is nearly double that for TSL 3, or about 7 TWh. Total

capacity is lower about 0.6 GW compared to the Reference Case.

14­8REFERENCES

1. U.S. Department of Energy/Energy Information Administration (DOE/EIA), Annual Energy

Outlook 2007

, February 2007. Washington, D.C. DOE/EIA­0383(2007).

14­9