### 1



## MEMO: UPDATED ESTIMATES OF MONETIZED GHG IMPACTS ASSOCIATED WITH THE PROPOSED HEAVY-DUTY AND FUEL EFFICIENCY STANDARDS

1 Introduction

Subsequent to the signature of the proposed heavy-d uty greenhouse (GHG) and fuel

efficiency standards, the Office of Management and Budget (OMB) posted a revised Technical

Support Document, Technical Update of the Social Cost of Carbon for R egulatory Impact

Analysis Under Executive Order 12866 (May 2013, Rev ised July 2015) . Referred to hereafter as

the “current TSD,” it presents two minor technical corrections to the current estimates of the

social cost of carbon (SC-CO 2 

### ). 1 

### One technical correction addressed an inadvertent omission of

climate change damages in the last year of analysis (2300) in one model and the second

addressed a minor indexing error in another model. The correction also affects the Marten et al.

(2014) estimates of the social cost of methane (SC- CH 4 

### ) and social cost of N 2 

### O (SC-N 2 

### O), which

were affected by the same indexing error and were u sed in a sensitivity analysis examining the

rulemaking’s non-CO 2 

### GHG impacts. This memo presents the revised estim ates of the

monetized GHG impacts associated with emission redu ctions expected from the proposed heavyduty GHG and fuel efficiency standards.

2 Updated Estimates of the SC-CO 2 

### , SC-CH 4 

### , SC-N 2 

### O

The corrected social cost of CO 2 

### , CH 4 

### , N 2 

### O (collectively, SC-GHG) estimates are shown

below. On average the revised SC-CO 2 

### estimates are one dollar less than the mean SC-CO 2 

### estimates reported in the November 2013 TSD. The ch ange in the estimates associated with the

95th percentile estimates when using a 3% discount rate is slightly larger, as those estimates are

heavily influenced by the results from the model th at was affected by the indexing error. The

percent change in the SC-CH 4 

### and SC-N 2 

### O estimates is likewise minor. Table 2-1 presents the

revised estimates of the SC-CO 2 

### and replaces preamble Table IX-13. Tables 2-2 and 2-3 present

1 Docket EPA-HQ-OAR-2014-0827, Technical Support Document: Technical Update of the Social Cost of Carbon for Regulatory Impact Analysis Under Executive Orde r 12866 , Interagency Working Group on Social Cost of Carbon, with participation by Council of Economic A dvisers, Council on Environmental Quality, Departme nt of Agriculture, Department of Commerce, Department of Energy, Department of Transportation, Domestic Poli cy Council, Environmental Protection Agency, National Economic Council, Office of Management and Budget, Office of Science and Technology Policy, and Depart ment of Treasury (May 2013, Revised July 2015).
Available at: http://www.whitehouse.gov/sites/default/files/omb/i nforeg/scc-tsd-final-july-2015.pdf

.

### 2

the corrected estimates of the SC-CH 4 

### and SC-N 2 

### O, respectively, and replace preamble table IX19.

Table 2-1 Social Cost of CO 2 

### , 2012 – 2050 a 

### (in 2012$ per Metric Ton)

CALENDAR
YEAR DISCOUNT RATE AND STATISTIC

5% Average 3% Average 2.5% Average 3% 95 th percentile
TSD Version Nov

2013 Revised Nov

2013 Revised Nov

2013 Revised Nov

2013 Revised

2012 $12 $12 $37 $36 $58 $57 $100 $100

2015 12 12 40 39 61 60 120 110
2020 13 13 46 45 69 67 140 130
2025 15 15 51 50 74 73 150 150
2030 17 17 56 54 81 79 170 160
2035 20 19 60 59 86 84 190 180
2040 23 23 66 65 93 91 210 200
2045 26 25 71 69 99 96 220 210
2050 28 28 77 74 100 100 240 230

Note:

a The SC-CO 2 values are dollar-year and emissions-year specific and have been rounded to two significant digits. The TSDs present SC-CO2 in $200 7. The unrounded numbers from the 2013 TSD and current TSD were adjusted to 2012$ using th e GDP Implicit Price Deflator. Also
available at: http://www.gpo.gov/fdsys/pkg/ECONI-2013-02/pdf/ECON I-2013-02-Pg3.pdf

.



### Table 2-2 Social Cost of CH 4 

### , 2012 – 2050 a 

### (in 2012$ per Metric Ton)

(Source: Marten et al. (2014))

CALENDAR
YEAR DISCOUNT RATE AND STATISTIC

5% Average 3% Average 2.5% Average 3% 95 th percentile
Source b 2014 Correction 2014 Correction 2014 Correction 2014 Correction
2012 $440 $430 $1000 $990 $1400 $1,400 $2800 $2,800

2015 500 490 1200 1,100 1500 1,500 3100 3,000
2020 590 580 1300 1,300 1700 1,700 3500 3,500
2025 710 700 1500 1,500 1900 1,900 4100 4,000
2030 840 820 1700 1,700 2300 2,200 4600 4,500
2035 990 970 2000 1,900 2500 2,500 5400 5,300
2040 1,200 1,100 2300 2,200 2800 2,800 6000 5,900
2045 1,300 1,300 2500 2,500 3100 3,000 6800 6,600
2050 1,500 1,400 2700 2,700 3300 3,300 7400 7,200

Note:

a . Marten et al. (2014) presents estimates, which a re emissions-year specific, in $2007. They were adjusted to 2012$ using the GDP Implicit Price Defl ator and rounded to two significant digits, as shown in Marten et al. (2014). GDP Implicit Price Deflator also available at: http://www.gpo.gov/fdsys/pkg/ECONI-2013-02/pdf/ECON I-2013-02-Pg3.pdf

.

### 3 b The rows marked “2014” refer to the original Marte n et al. (2014) publication and those marked “Correction” refer to the Marten et al. (2014) Erra tum submitted to Climate Policy in July 2015.
The Erratum corrects the estimates.



### Table 2-3 Social Cost of N 2 

### O, 2012 – 2050 a 

### (in 2012$ per Metric Ton)

(Source: Marten et al. (2014))

CALENDAR
YEAR DISCOUNT RATE AND STATISTIC

5% Average 3% Average 2.5% Average 3% 95 th percentile

Source b 2014 Correction 2014 Correction 2014 Correction 2014 Correction

2012 $4000 $3,900 $14000 $13,000 $20000 $20,000 $37000 $35,000

2015 4400 4,300 15000 14,000 22000 22,000 39000 38,000
2020 5200 5,100 16000 16,000 24000 24,000 44000 42,000
2025 6000 5,900 18000 18,000 27000 26,000 50000 47,000
2030 7000 6,800 20000 20,000 29000 29,000 55000 53,000
2035 8100 8,000 23000 23,000 32000 31,000 61000 59,000
2040 9300 9,100 25000 25,000 35000 35,000 67000 65,000
2045 11000 10,000 27000 27,000 38000 37,000 73000 71,000
2050 12000 12,000 29000 29,000 41000 40,000 80000 78,000

Note:

a . Marten et al. (2014) presents estimates, which a re emissions-year specific, in $2007. They were adjusted to 2012$ using the GDP Implicit Price Defl ator and rounded to two significant digits, as shown in Marten et al. (2014). GDP Implicit Price Deflator also available at: http://www.gpo.gov/fdsys/pkg/ECONI-2013-02/pdf/ECON I-2013-02-Pg3.pdf

. b The rows marked “2014” refer to the original Marte n et al. (2014) publication and those marked “Correction” refer to the Marten et al. (2014) Erra tum submitted to Climate Policy in July 2015.
The Erratum corrects the estimates.



### 3 Updated Estimates of Monetized GHG Impacts from t he Proposal

The approach used to value the proposal’s anticipat ed GHG impacts, i.e., the application of

the social cost estimates to changes in emissions, remains the same and is described in detail in

Chapter 8 of the Regulatory Impact Analysis. For b revity, this memo reports the results of

applying the revised SC-GHG estimates to the expect ed changes in emissions.

The application of the revised SC-CO 2 

### estimates does not change the key findings of the

economic analysis. The net benefits estimated in e ach year of the analysis period (2018 through

2050) remain positive, though decrease slightly (e. g., by 0.19 percent in year 2035 and 0.48

### 4

percent in year 2050 when using the central SC-CO 2 

### ). 2 

### Likewise, the proposed rulemaking’s

annual benefit estimates, i.e., the sum of GHG and non-GHG benefits in a certain year, decrease

when using the corrected SC-CO 2 

### estimates (e.g., by 0.49 percent in 2035 and 1.2 p ercent in

2050 when using the central SC-CO 2 

### ).

Tables 3-1 through 3-4 present the revised summarie s of benefits and net benefit estimates

of the proposed rule, hereby replacing an Executive Summary table from the preamble and

preamble Tables IX-34, IX-35, and IX-36, respective ly. In Tables 3-1 through 3-4, the estimates

published in the preamble are shown in parentheses next to the revised estimates; only one

number is shown if the preamble estimates were not affected.

Table 3-1 Summary of the Proposed Phase 2 Medium- a nd Heavy-Duty Vehicle Annual Fuel and GHG Reductions, Program Costs, Benefits and Net Benefit s in Calendar Years 2035 and 2050, Based on Analysi s Method B a



### 2035

(preamble) revised 

### 2050 (preamble) revised 

### Fuel Reductions (Billion Gallons) 9.3 13.4 GHG Reduction (MMT, CO 2- 

### Eq) 127.1 183.4 Vehicle Program Costs (including Maintenance; Billions of 2012$) -$6.0 -$7.1

Fuel Savings (Pre-Tax; Billions of 2012$) $37.2 $57 .5 Benefits (Billions of 2012$) ($20.5) $20.4 ($32.9) $32.5 Net Benefits (Billions of 2012$) ($51.7) $51.6 ($83.2) $82.8

Notes:

a Benefits and net benefits use the 3 percent averag e SCC-CO 2 value applied only to CO 2 emissions; GHG
reductions include CO 2 , CH 4 , N 2 O and HFC reductions; values reflect the preferred alternative relative to the less dynamic baseline (a reference case that projec ts very little improvement in new vehicle fuel econ omy absent new standards).

2 The central SC-CO 2 is the model average SC-CO 2 estimate at a 3 percent discount rate. The percent change in net benefits and benefits are calculated using rounded values in the table.

### 5

Table 3-2 Annual Benefits & Costs of the Preferred Alternative and Net Present Values at 3% and 7% Discount Rates using Method B and Relative to the L ess Dynamic Baseline (Billions of 2012$) a

2018 2021 2024 2030 2035 2040 2050 NPV,
3% NPV,

7% Vehicle program -$0.1 -$2.4 -$3.7 -$5.4 -$5.9 -$6.3 -$7.0 -$86.8 -$41.1

Maintenance $0.0 $0.0 -$0.1 -$0.1 -$0.1 -$0.1 -$0. 1 -$1.8 -$0.9 Pre-tax fuel $0.2 $1.7 $6.9 $24.0 $37.2 $47.8 $57. 5 $495.6 $206.7 Energy security $0.0 $0.1 $0.3 $1.3 $2.2 $2.9 $3.5 $28.9 $11.9
Accidents/Congestion/Noise $0.0 -$0.1 -$0.3 -$0.5 -$0.7 -$0.8 -$0.9 -$9.3 -$4.2

Refueling impacts $0.0 $0.0 $0.1 $0.4 $0.7 $0.9 $1. 2 $9.4 $3.9 Travel value $0.0 $0.4 $1.0 $1.9 $2.4 $2.9 $3.3 $34.2 $15.3 Non-GHG impacts $0.0

to $0.1 $0.4

to $0.9 $1.0 to

$2.4 $3.3 to

$8.3 $4.8 to $12.1 $5.7 to

$14.3 $7.0 to

$17.5 $69.7 to

$157.0 $26.6 to

$60.4

SCC b,c
SCC_CO 2 ; 5% Avg $0.0 $0.1 $0.4 $1.5 ($2.5) $2.4 $3.3 $5.0 ($22.1) $21.6 ($22.1)

$21.6
SCC_CO 2 ; 3% Avg $0.0 $0.3 $1.3 ($4.8) $4.6 ($7.4)

$7.3 ($9.7)

$9.5 ($13.6)

$13.2 ($103.1)

$100.7 ($103.1)

$100.7

SCC_CO 2 ; 2.5% Avg $0.1 $0.5 $1.9 ($6.9) $6.7 ($10.6) $10.3 ($13.7)

$13.3 ($18.5)

$18.1 ($164.1)

$160.3 ($164.1)

$160.3

SCC_CO 2 ; 3% 95th $0.1 $1.0 ($4.0) $3.9 ($14.6) $13.9 ($23.2)

$22.2 ($30.3)

$29.1 ($42.0)

$40.5 ($320.5)

$307.5 ($320.5)

$307.5

Net benefits d
SCC_CO 2 ; 5% Avg $0.2 $0.4 ($6.4) $6.3 $28.8 ($46.8)

$46.7 $60.6 $74.6 ($605.8) $605.2 ($257.1)

$256.6

SCC_CO 2 ; 3% Avg $0.2 $0.7 $7.3 ($32.1) $31.9 ($51.7)

$51.6 ($66.9)

$66.8 ($83.2)

$82.8 ($686.8)

$684.3 $335.6

SCC_CO 2 ; 2.5% Avg $0.2 $0.8 $7.9 ($34.2) $34.0 ($54.9)

$54.7 ($70.9)

$70.6 ($88.2)

$87.8 ($747.8)

$743.9 $395.3

SCC_CO 2 ; 3% 95th $0.3 $1.3 ($10.0) $9.8 ($41.9) $41.3 ($67.5)

$66.6 ($87.6)

$86.3 ($111.7)

$110.2 ($904.1)

$891.1 $542.4

Notes: The estimates published in the preamble are shown i n parentheses next to the revised estimates; only o ne number is shown if the preamble estimates were not affected

.

a Positive values denote decreased social costs (ben efits); negative values denote increased social cos ts. For an explanation of analytical Methods A and B, please s ee Section I.D; for an explanation of the less dyna mic baseline, 1a, and more dynamic baseline, 1b, please see Secti on X.A.1.

### 6 b Net present value of reduced CO 2 emissions is calculated differently than other ben efits. The same discount rate used to discount the value of damages from future e missions (SC-CO 2 at 5, 3, 2.5 percent) is used to calculate net present value of SC-CO 2 for internal consistency. Refer to the SCC TSD for more detail.

c Section IX.G notes that SC-CO 2 increases over time. For the years 2012-2050, the SC-CO 2 estimates range as follows: for Average SC-CO 2 at 5%: $12-$28; for Average SC-CO 2 at 3%: $36-$75; for Average SC-CO 2 at 2.5%: $57-$103; and for 95th percentile SC-CO 2 at 3%: $100-$230. Section IX.G also presents thes e SC-CO 2 estimates.

d Net impacts are the summation of results within co lumns of the table with the exception that the net impacts at
each SC-CO 2 value include only the SC-CO 2 impacts at that value.

Table 3-3 Discounted Model Year Lifetime Benefits & Costs of the Preferred Alternative using Method B and Relative to the Less Dynamic Baseline (Billions of 2012$ discounted at 3%) a

2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 SUM
Vehicle

program -

$0.1 - $0.1 -$0.1 -$2.0 -$1.9 -$1.9 -$2.8 -$2.7 -$2.7 -$3.7 -$3.6 -$3.5 -$25.1

Maintenance -

$0.1 $0.0 $0.0 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$1.1

Pre-tax fuel $1.9 $1.9 $1.8 $11.1 $11.5 $11.9 $18.9 $19.6 $20.2 $24.1 $24.1 $24.1 $171.1 Energy security $0.1 $0.1 $0.1 $0.5 $0.6 $0.6 $1.0 $1.1 $1.1 $1.4 $1.4 $1.4 $9.3

Accidents/ Congestion/
Noise -

$0.1 - $0.1 -$0.2 -$0.4 -$0.4 -$0.4 -$0.4 -$0.4 -$0.4 -$0.4 -$0.4 -$0.4 -$4.2

Refueling $0.0 $0.0 $0.0 $0.2 $0.2 $0.2 $0.3 $0.3 $0.4 $0.5 $0.5 $0.5 $3.1 Travel value $0.6 $0.6 $0.7 $1.5 $1.5 $1.5 $1.4 $1.4 $1.4 $1.4 $1.4 $1.4 $14.9 Non-GHG $0.2

to $0.5 $0.2

to $0.4 $0.2

to $0.4 $2.0 to

$4.5 $2.0 to

$4.5 $2.0 to

$4.5 $2.9 to

$6.6 $3.0 to

$6.8 $2.6 to

$5.9 $3.1 to

$6.9 $3.1 to

$6.9 $3.1 to

$7.0 $24.4 to

$55.0

SCC b,c
SCC_CO 2 ; 5% Avg $0.1 $0.1 $0.1 $0.5 $0.5 $0.5 ($0.9) $0.8 $0.9 $0.9 $1.1 $1.1 $1.1 ($7.8) $7.6 SCC_CO 2 ; 3% Avg $0.4 $0.4 $0.4 ($2.2) $2.1 ($2.3)

$2.2 $2.3 ($3.7)

$3.6 ($3.9)

$3.8 ($4.0)

$3.9 ($4.8)

$4.7 ($4.8)

$4.7 ($4.9)

$4.7 ($34.0)

$33.2 SCC_CO 2 ; 2.5% Avg $0.6 $0.6 ($0.6) $0.5 ($3.4)

$3.3 ($3.5)

$3.4 $3.6 ($5.8)

$5.7 ($6.1)

$6.0 ($6.3)

$6.2 ($7.6)

$7.4 ($7.6)

$7.5 ($7.7)

$7.5 ($53.4)

$52.2 SCC_CO 2 ; 3% 95th $1.1 $1.1 $1.1 ($6.6) $6.4 ($6.9)

$6.6 ($7.2)

$6.9 ($11.5) $11.0 ($12.0)

$11.5 ($12.4)

$11.9 ($14.9)

$14.3 ($15.0)

$14.4 ($15.1)

$14.5 ($105.0)

$100.7
Net benefits

d
SCC_CO 2 ; 5% Avg $2.8 $2.7 $2.7 $14.6 $15.1 $15.5 $23.9 $25.0 $25.1 $29.2 ($29.4) $29.3 $29.4 ($215.5)

$215.3 SCC_CO 2 ; 3% Avg $3.0 $3.0 $3.0 $16.2 $16.8 $17.3 ($26.8) $26.7 ($28.0)

$27.9 ($28.2)

$28.1 ($33.0)

$32.8 ($33.1)

$33.0 ($33.2)

$33.1 ($241.7)

$240.9 SCC_CO 2 ; 2.5% Avg $3.2 $3.2 $3.2 $17.4 ($18.1) $18.0 ($18.6)

$18.5 ($28.9)

$28.8 ($30.2)

$30.0 ($30.5)

$30.4 ($35.7)

$35.6 ($35.9)

$35.8 ($36.0)

$35.9 ($261.1)

$259.9 SCC_CO 2 ; 3% 95th $3.8 $3.7 $3.7 ($20.7) $20.4 ($21.5)

$21.2 ($22.1)

$21.9 ($34.5)

$34.1 ($36.0)

$35.6 ($36.6)

$36.1 ($43.1)

$42.4 ($43.3)

$42.7 ($43.5)

$42.8 ($312.7)

$308.4

Notes: The estimates published in the preamble are shown i n parentheses next to the revised estimates; only o ne number is shown if the preamble estimates were not affected

.

a Positive values denote decreased social costs (ben efits); negative values denote increased social cos ts. For an explanation of analytical Methods A and B, please s ee Section I.D; for an explanation of the less dyna mic baseline, 1a, and more dynamic baseline, 1b, please see Secti on X.A.1.c

### 7 b Net present value of reduced CO 2 emissions is calculated differently than other ben efits. The same discount rate used to discount the value of damages from future e missions (SC-CO 2 at 5, 3, 2.5 percent) is used to calculate net present value of SC-CO 2 for internal consistency. Refer to the SCC TSD fo r more detail.

c Section IX.G notes that SCC increases over time. F or the years 2012-2050, the SC-CO 2 estimates range as follows: for Average SC-CO 2 at 5%: $12-$28; for Average SC-CO 2 at 3%: $36-$75; for Average SC-CO 2 at 2.5%: $57- $103; and for 95th percentile SC-CO 2 at 3%: $100-$230. Section IX.G also presents thes e SC-CO 2 estimates. Section IX.G also presents these SCC estimates.

d Net impacts are the summation of results within co lumns of the table with the exception that the net impacts at
each SC-CO 2 value include only the SCCO 2 impacts at that value.

Table 3-4 Discounted Model Year Lifetime Benefits & Costs of the Preferred Alternative using Method B and Relative to the Less Dynamic Baseline (Billions of 2012$ discounted at 7%) a

2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 S UM
Vehicle

program -

$0.1 - $0.1 -$0.1 -$1.6 -$1.4 -$1.4 -$1.9 -$1.8 -$1.7 -$2.3 -$2 .1 -$2.0 -$16.6

Maintenance $0.0 $0.0 $0.0 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0.1 -$0. 1 $0.0 -$0.6 Pre-tax fuel $1.4 $1.3 $1.2 $6.9 $6.9 $6.8 $10.5 $10.4 $10.4 $11.9 $11.5 $11.0 $90.1 Energy security $0.1 $0.1 $0.1 $0.3 $0.3 $0.4 $0.5 $0.6 $0.6 $0.7 $0.7 $0.6 $4.8

Accidents/ Congestion/
Noise -

$0.1 - $0.1 -$0.1 -$0.3 -$0.3 -$0.2 -$0.2 -$0.2 -$0.2 -$0.2 -$0.2 -$0.2 -$2.4

Refueling $0.0 $0.0 $0.0 $0.1 $0.1 $0.1 $0.2 $0.2 $0.2 $0.2 $0.2 $0.2 $1.6 Travel value $0.4 $0.4 $0.4 $0.9 $0.9 $0.8 $0.8 $0.8 $0.7 $0.7 $0.7 $0.6 $8.2 Non-GHG $0.1

to $0.3 $0.1

to $0.3 $0.1

to $0.3 $1.1 to

$2.5 $1.1 to

$2.4 $1.0 to

$2.3 $1.4 to

$3.3 $1.4 to

$3.2 $1.2 to

$2.7 $1.3 to

$3.0 $1.3 to

$2.9 $1.3 to

$2.8 $11.5 to

$26.0

SCC b,c
SCC_CO 2 ; 5% Avg $0.1 $0.1 $0.1 $0.5 $0.5 $0.5 ($0.9) $0.8 $0.9 $0.9 $1.1 $1.1 $1.1 ($7.8) $7.6 SCC_CO 2 ; 3% Avg $0.4 $0.4 $0.4 ($2.2) $2.1 ($2.3)

$2.2 $2.3 ($3.7)

$3.6 ($3.9)

$3.8 ($4.0)

$3.9 ($4.8)

$4.7 ($4.8)

$4.7 ($4.9)

$4.7 ($34.0)

$33.2 SCC_CO 2 ; 2.5% Avg $0.6 $0.6 ($0.6) $0.5 ($3.4)

$3.3 ($3.5)

$3.4 $3.6 ($5.8)

$5.7 ($6.1)

$6.0 ($6.3)

$6.2 ($7.6)

$7.4 ($7.6)

$7.5 ($7.7)

$7.5 ($53.4)

$52.2 SCC_CO 2 ; 3% 95th $1.1 $1.1 $1.1 ($6.6) $6.4 ($6.9)

$6.6 ($7.2)

$6.9 ($11.5) $11.0 ($12.0)

$11.5 ($12.4)

$11.9 ($14.9)

$14.3 ($15.0)

$14.4 ($15.1)

$14.5 ($105.0)

$100.7
Net benefits d
SCC_CO 2 ; 5% Avg $1.9 $1.8 $1.7 $8.7 $8.7 $8.7 ($13.0) $12.9 $13.1 $12.7 ($14.3) $14.2 $13.8 $13.4 ($111.8) $111.6 SCC_CO 2 ; 3% Avg $2.2 $2.1 $2.0 $10.3 $10.4 ($10.5) $10.4 ($15.8)

$15.7 ($16.1)

$16.0 ($15.8)

$15.7 ($18.0)

$17.9 ($17.6)

$17.5 ($17.2)

$17.1 ($138.0)

$137.2 SCC_CO 2 ; 2.5% Avg $2.4 $2.3 $2.2 $11.5 ($11.7) $11.6 ($11.8)

$11.7 ($17.9)

$17.8 ($18.3)

$18.2 ($18.1)

$18.0 ($20.7)

$20.6 ($20.4)

$20.2 ($20.0)

$19.8 ($157.4)

$156.2 SCC_CO 2 ; 3% 95th $2.9 $2.8 ($2.8) $2.7 ($14.8) $14.5 ($15.1)

$14.8 ($15.3)

$15.0 ($23.6)

$23.1 ($24.2) $23.7) ($24.2)

$23.7 ($28.1)

$27.5 ($27.8)

$27.2 ($27.4)

$26.8 ($209.0)

$204.7

Notes: The estimates published in the preamble are shown i n parentheses next to the revised estimates; only o ne number is shown if the preamble estimates were not affected

.

a Positive values denote decreased social costs (ben efits); negative values denote increased social cos ts. For an explanation of analytical Methods A and B, please s ee Section I.D; for an explanation of the less dyna mic baseline, 1a, and more dynamic baseline, 1b, please see Secti on X.A.1.c

### 8 b Net present value of reduced CO 2 emissions is calculated differently than other ben efits. The same discount rate used to discount the value of damages from future e missions (SC-CO 2 at 5, 3, 2.5 percent) is used to calculate net present value of SC-CO 2 for internal consistency. Refer to the SCC TSD fo r more detail.

c Section IX.G notes that SCC increases over time. F or the years 2012-2050, the SC-CO 2 estimates range as follows: for Average SC-CO 2 at 5%: $12-$28; for Average SC-CO 2 at 3%: $36-$75; for Average SC-CO 2 at 2.5%: $57- $103; and for 95th percentile SC-CO 2 at 3%: $100-$230. Section IX.G also presents thes e SC-CO 2 estimates. Section IX.G also presents these SCC estimates.

d Net impacts are the summation of results within co lumns of the table with the exception that the net impacts at
each SC-CO 2 value include only the SCCO 2 impacts at that value.



### Tables 3-5 and 3-6 present the revised estimates of the monetized benefits associated with

CO 2 

### reductions for the calendar year and model year an alyses, respectively. Tables 3-5 and 3-6

replace preamble Tables IX-14 and IX-15, respective ly.

Table 3-5 Upstream and Downstream Annual CO 2 

### Benefits for the Given SC-CO 2 

### Value a 

### using Method B and Relative to the Less Dynamic Baseline (Millions of 2012$) b

CALENDAR
YEAR 5%

AVERAGE 3%

AVERAGE 2.5%

AVERAGE 3%,

95 TH PERCENTILE 2018 $13 $43 $64 $120 2019 $26 $89 $130 $260 2020 $40 $140 $200 $410 2021 $92 $320 $490 $970 2022 $170 $570 $850 $1,700 2023 $250 $840 $1,200 $2,500 2024 $370 $1,300 $1,900 $3,900 2025 $540 $1,800 $2,600 $5,300 2026 $670 $2,300 $3,300 $6,800 2027 $890 $2,900 $4,200 $8,500 2028 $1,100 $3,500 $5,000 $10,000 2029 $1,200 $4,000 $5,900 $12,000 2030 $1,500 $4,600 $6,700 $14,000 2035 $2,400 $7,300 $10,000 $22,000 2040 $3,300 $9,500 $13,000 $29,000 2050 $5,000 $13,000 $18,000 $41,000 NPV $22,000 $100,000 $160,000 $310,000

Notes:

a The SC-CO 2 values are dollar-year and emissions-year specific

. b For an explanation of analytical Methods A and B, p lease see preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and m ore dynamic baseline, 1b, please see preamble Section X.A.1.

### 9

Table 3-6 Upstream and Downstream Discounted Model Year Lifetime CO2 Benefits for the Given SC-CO2 Value using Method B and Relative to the Les s Dynamic Baseline (Millions of 2012$) a, b

MODEL
YEAR 5%

AVERAGE 3%

AVERAGE 2.5%

AVERAGE 3%,

95 TH PERCENTILE 2018 $92 $370 $570 $1,100 2019 $88 $360 $560 $1,100 2020 $85 $350 $550 $1,100 2021 $510 $2,100 $3,300 $6,400 2022 $520 $2,200 $3,400 $6,600 2023 $530 $2,300 $3,600 $6,900 2024 $850 $3,600 $5,700 $11,000 2025 $870 $3,800 $6,000 $11,000 2026 $900 $3,900 $6,200 $12,000 2027 $1,100 $4,700 $7,400 $14,000 2028 $1,100 $4,700 $7,500 $14,000 2029 $1,100 $4,700 $7,500 $14,000 Sum $7,600 $33,000 $52,000 $100,000

Notes:

a The SC-CO 2 values are dollar-year and emissions-year specific

. b For an explanation of analytical Methods A and B, p lease see preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and m ore dynamic baseline, 1b, please see preamble Section X.A.1.



### The non-CO 2 

### benefit estimates shown in the proposed rulemaking ’s sensitivity analysis

have also been revised using the corrected SC-GHG e stimates. The sensitivity analysis

presented non-CO 2 

### GHG benefits based on two approaches, the Global W arming Potential

(GWP) approximation approach and the use of directl y modeled estimates of the SC-CH 4 

### and

SC-N 2 

### O. The methodology for these two approaches remain s the same and is described in detail

in Chapter 8 of the Regulatory Impact Analysis.

Tables 3-7 to 3-9 in this memo replace preamble Tab les IX-16 to IX-18, which present

benefit estimates based on the Global Warming Poten tial (GWP) approximation approach. Table

3-10 in this memo replaces preamble Table IX-20, wh ich presents the updated CH 4 

### and N 2 

### O

benefit estimates based on corrected estimates of t he directly modeled SC-CH 4 

### and SC-N 2 

### O.

### 10

Table 3-7 Annual Upstream and Downstream CH 4 

### Benefits for the Given SC-CO 2 

### Value using Method B and Relative to the Less Dynamic Baseline, Using the GWP Approach a,b 

### (Millions of 2012$) b

CH 4 Calendar
Year 5% Average 3%

Average 2.5%

Average 3%,

95 th Percentile 2018 $0.3 $1.1 $1.6 $3.0 2019 $0.6 $2.2 $3.2 $6.4 2020 $1.0 $3.4 $5.0 $10 2021 $3.1 $11 $16 $32 2022 $6 $20 $30 $59 2023 $9 $30 $44 $89 2024 $13 $45 $66 $130 2025 $19 $61 $90 $180 2026 $23 $78 $110 $230 2027 $30 $97 $140 $290 2028 $36 $120 $170 $350 2029 $41 $130 $200 $400 2030 $49 $150 $220 $460 2035 $78 $240 $340 $730 2040 $110 $310 $430 $950 2050 $160 $430 $590 $1,300 NPV $710 $3,300 $5,300 $10,000

Notes:

a The SC-CO 2 values are dollar-year and emissions-year specific

b For an explanation of analytical Methods A and B, please see preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline, 1b, please see preamble Sect ion X.A.1.

. 

### Table 3-8 Annual Upstream and Downstream N 2 

### O Benefits for the Given SC-CO 2 

### Value using Method B and Relative to the Less Dynamic Baseline, Using the GWP Approach a,b 

### (Millions of 2012$) b

N 2 O
Calendar
Year 5% Average 3%

Average 2.5%

Average 3%,

95 th Percentile 2018 $0.0 $0.0 $0.1 $0.1 2019 $0.0 $0.1 $0.2 $0.3 2020 $0.0 $0.2 $0.2 $0.5 2021 $0.1 $0.4 $0.5 $1.0 2022 $0.2 $0.6 $0.9 $1.9 2023 $0.3 $0.9 $1.4 $2.7 2024 $0.4 $1.4 $2.1 $4.2 2025 $0.6 $1.9 $2.9 $5.8 2026 $0.7 $2.5 $3.7 $7.5 2027 $1.0 $3.2 $4.6 $10 2028 $1.2 $3.9 $5.6 $12 2029 $1.4 $4.5 $6.6 $14 2030 $1.6 $5.1 $7.5 $16 2035 $2.7 $8 $12 $25 2040 $3.8 $11 $15 $33

### 11 2050 $5.6 $15 $20 $46 NPV $24 $110 $180 $350

Notes:

a The SC-CO 2 values are dollar-year and emissions-year specific.

b For an explanation of analytical Methods A and B, p lease see preamble Section I.D; for an explanation of the les s dynamic baseline, 1a, and more dynamic baseline, 1b, please see preamble
Section X.A.1.



### Table 3-9 Annual Upstream and Downstream HFC-134a Benefits for the Given SC-CO 2 

### Value using Method B and Relative to the Less Dynamic Bas eline, Using the GWP Approach a,b 

### (Millions of 2012$) b

HFC-134A
Calendar
Year 5% Average 3%

Average 2.5%

Average 3%,

95 th Percentile 2018 $0.0 $0.0 $0.0 $0.0 2019 $0.0 $0.0 $0.0 $0.0 2020 $0.0 $0.0 $0.0 $0.0 2021 $0.2 $0.8 $1.2 $2.5 2022 $0.5 $1.7 $2.5 $5.1 2023 $0.8 $2.6 $3.8 $7.8 2024 $1.0 $3.6 $5.2 $11 2025 $1.4 $4.6 $6.8 $14 2026 $1.7 $5.7 $8.4 $17 2027 $2.2 $6.9 $10 $21 2028 $2.5 $8.2 $12 $24 2029 $2.8 $9 $14 $28 2030 $3.4 $11 $16 $32 2035 $4.9 $15 $21 $46 2040 $6.1 $18 $25 $53 2050 $8.4 $22 $31 $69 NPV $43 $200 $320 $610

Notes:

a The SC-CO 2 values are dollar-year and emissions-year specific.

b For an explanation of analytical Methods A and B, p lease see preamble Section I.D; for an explanation of the les s dynamic baseline, 1a, and more dynamic baseline, 1b, please see preamble
Section X.A.1.

### 12

Table 3-10 Annual Upstream and Downstream non-CO 2 

### GHG Benefits for the Given SC-non-CO2 Value using Method B and Relative to the Less Dynam ic Baseline, Using the Directly Modeled Approach a,b 

### (Millions of 2012$) c

YEA
R SC-CH 4 SC-N 2 O

5% Average 3%

Average 2.5%

Average 3%

95 th percentile 5%

Average 3%

Average 2.5%

Average 3%

95 th percentile 2018 $0.5 $1.2 $1.6 $3.2 $0.0 $0.1 $0.1 $0.2 2019 $1.1 $2.5 $3.3 $6.6 $0.0 $0.1 $0.2 $0.3 2020 $1.7 $3.9 $5.2 $10 $0.1 $0.2 $0.3 $0.5 2021 $5.7 $13 $17 $34 $0.1 $0.4 $0.6 $1.1 2022 $11 $24 $31 $63 $0.2 $0.8 $1.1 $2.0 2023 $16 $36 $47 $95 $0.4 $1.1 $1.6 $2.9 2024 $25 $54 $70 $140 $0.6 $1.7 $2.5 $4.5 2025 $34 $74 $95 $200 $0.8 $2.4 $3.4 $6.2 2026 $44 $95 $120 $250 $1.0 $3.1 $4.4 $8.0 2027 $56 $120 $150 $310 $1.3 $4.0 $5.6 $10 2028 $68 $140 $180 $380 $1.6 $4.8 $6.8 $12 2029 $80 $170 $210 $450 $1.9 $5.7 $8.1 $15 2030 $92 $190 $240 $510 $2.2 $6.5 $9.3 $17 2035 $160 $310 $400 $850 $3.7 $10 $14 $27 2040 $210 $410 $540 $1,100 $5.0 $14 $19 $36 2050 $320 $620 $770 $1,700 $7.9 $20 $27 $52 NPV $1,400 $4,500 $6,300 $12,000 $33 $150 $230 $380

Notes:

a The values are emissions-year specific and have bee n rounded to two significant digits. Unrounded numb ers were used to calculate the GHG benefits.

b Note that net present discounted values of reduced GHG emissions are calculated differently than other benefits.
The same discount rate used to discount the value o f damages from future emissions (SC-CH 4 and SC- N 2 O at 5, 3, and 2.5 percent) is used to calculate net present v alue discounted values of SC-CH 4 and SC- N 2 O for internal consistency. Refer to SCC TSD for more detail.

c For an explanation of analytical Methods A and B, p lease see preamble Section I.D; for an explanation of the less dynamic baseline, 1a, and more dynamic baseline, 1b , please see preamble Section X.A.1.



### 4 References

Technical Support Document: Technical Update of the Social Cost of Carbon for Regulatory Impact Analysis Under Executive Order 12866 , Interagency Working Group on Social Cost of Carbo n, with participation by Council of Economic Advisers, Coun cil on Environmental Quality, Department of Agriculture, Department of Commerce, Department of Energy, Department of Transportation, Environmental Protection Agency, National Economic Council, Office of Energy and Climate Change, Office of Management and Budget, Office of Science and Technology Policy, and Department of Treasury (May 2013, Revised July 2015). Available a t: http://www.whitehouse.gov/sites/default/files/omb/i nforeg/scc-tsd-final-july-2015.pdf

.