Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

1

                                                           

Below is a summary of interagency comments received during EO 12866 review of the draft rule 

“Revisions to Motor Vehicle Fuel Economy Label.” They are for your consideration and subject 

to further policy review. 

Draft Preamble Section II.B.4.a 

a. Upstream Emissions 

This section discusses how the agencies plan to address the issue of greenhouse gas 

emissions associated with the use of motor vehicles, in the context of a program specifically 

designed to provide consumers with information that will be useful when purchasing a vehicle. 

The agencies’ approach takes into account (1) the statutory language, (2) the fact that the law 

requires a great deal of information to be presented on the label, (3) the limited amount of 

information that can be provided on a label, (4) the importance of simplicity, clarity, accuracy, 

and intelligibility on the label, (and (5) the ability to provide the public with additional and 

comprehensive information in a consumer-friendly format on a website.1 This discussion 

focuses on, but is not limited to, the advanced technology vehicles that use electricity from the 

grid to power vehicles, such as the electric vehicles and plug-in hybrids that are expected to enter 

the market in larger numbers in the coming years; the discussion also refers to the use of 

renewable fuels in gasoline-powered vehicles. 

As explained below, our proposed approach would limit the label to tailpipe-only 

emissions while providing much fuller information on a website. But we also identify, and seek 

comments on, alternative approaches, also designed to accommodate the relevant variables. 

The agencies believe that the proposed approach follows from a reasonable interpretation 

of the Energy Policy and Conservation Act (EPCA), as amended by the Energy Independence 

and Security Act (EISA) of 2007. The statute states that NHTSA must require vehicles to be 

labeled with information “reflecting an automobile’s performance ... [with respect to] 

greenhouse gas ... emissions ... of the automobile.”2

 This information is to be based on criteria 

developed by EPA. NHTSA believes that a reasonable interpretation of this provision is that 

only GHG emissions directly from the vehicle itself are required for the label. On that 

interpretation, the information on performance and the rating of the vehicles would both be based 

on the emissions of the vehicle itself. This interpretation is also consistent with the history of the 

EPA labeling program and its focus on the vehicle itself. NHTSA believes that it would also be 

reasonable to interpret the statutory language such that the required label information on GHG 

1

 On the relationship between summary disclosure, as on the label, and full disclosure, as on the website, see [OIRA 

guidance document]. 

2

 49 U.S.C. 32908(g)(1)(A)(i). 49 U.S.C.32908(g)(1)(A)(ii) also refers to GHG “emissions of automobiles,” and further requires a designation of 

automobiles “with the lowest greenhouse gas emissions over the useful life of the vehicles.”
Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

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emissions would include additional information on the upstream GHG emissions associated with 

electricity or other fuels used by the vehicle. This additional information could provide a 

broader context for reflecting the automobile’s performance with respect to GHG emissions. 

The agencies recognize that “lifecycle” GHG emissions are associated with the 

production and distribution of all automotive fuels used by motor vehicles. Lifecycle GHG 

emissions are associated with gasoline, diesel, and other fuels such as natural gas, electricity, and 

renewable biofuels. The agencies also recognize that tailpipe-only emissions provide important 

information but that a significant number of consumers may want, or benefit from, access to 

information on the total upstream GHG emissions associated with the operation of their vehicles. 

For example, electric vehicles do not have any tailpipe emissions since their motors do not burn 

fuel, but producing the electricity used to power such vehicles most likely emits greenhouse 

gases. Consumers might seek, or benefit from, a label that allows for simple and accurate 

comparisons across vehicles on the total upstream GHG emissions, in addition to tailpipe 

emissions. However, the agencies emphasize that developing the relevant information, and 

providing it to consumers in a manner that is accurate and meaningful, raises a number of 

challenging issues, particularly in the context of the label. 

A full lifecycle evaluation would include an evaluation of a comprehensive set of GHG 

and energy impacts associated with both the vehicle (extraction and processing of materials, 

energy used in assembly, distribution, use, and disposal, etc.), and the fuel (feedstock extraction, 

feedstock transport, fuel processing, fuel transport, etc.). In practice, however, offering even the 

more limited accounting for GHG emissions from production and distribution of the fuel, 

including electricity, presents complex challenges. EPA currently does not measure fuel 

combustion/electricity generation GHG emissions in its vehicle testing. The agencies recognize 

that modeling can be performed to assist in estimating these emissions. But in developing 

upstream GHG emissions values, modeling would need to be done carefully to avoid inaccuracy 

and consumer confusion, especially in light of variations across time and across regions. For 

example, GHG emissions from electricity generation will vary significantly in the future, based 

on the different fuels used at generating stations -- perhaps by as much as an order of magnitude 

between coal and non-fossil feedstocks. 

It is true that the EPA has undertaken extensive lifecycle modeling of biofuels for the 

Renewable Fuel Standard rulemaking in response to the requirements of the Energy 

Independence and Security Act. But that assessment was done in the context of the particular 

mix of biofuels required nationally in 2022 by the Act, with a series of assumptions and 

estimates that may not be accurate today. 
Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

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One overriding issue is whether the agencies could reasonably provide a single, national 

value for GHG emissions from electricity generation or could provide instead different values 

customized for various regions of the country.3

 There are data sources upon which a single 

national number could be derived. For individual owners, however, a single national value would 

generally not be accurate, and the individual would need access to additional information, such 

as regional values, to evaluate the impact of a specific vehicle.4

 In addition, the agencies would 

have to decide (1) whether to use average or marginal (i.e., reflecting the fact that increased 

vehicle demand might change the overall mix of electricity sources) GHG emissions factors, and 

(2) if the marginal approach is used, whether to assume all nighttime charging or a mix of 

daytime and nighttime charging. Another major consideration is whether to base electricity 

generation GHG emissions values on today's electricity markets or on projected changes in 

electricity markets that might occur by 2020 or some other year (note that vehicles produced in 

the next few years will remain in the fleet for 15 or 20 years or more). 

Some states have already passed legislation that could require major changes in how 

electricity is produced in those states in the future, and Congress has considered landmark 

legislation as well. It is clear that the question of how electricity will be produced in the future is 

a very fluid issue. As a result of the Energy Independence and Security Act biofuel mandates, 

the agencies expect the amount of biofuel in the transportation fuel market to increase 

significantly over time, and the contribution of feedstocks to change over that time as well. 

Information that addresses lifecycle emissions of biofuels would need to take these 

considerations into account. 

The agencies believe that all of these complex factors can be best addressed by providing 

a great deal of relevant information on a website, which can go into great depth and be changed 

and updated as appropriate. We currently do not have a full lifecycle analysis from which to 

draw for labeling purposes across the full range of vehicles and fuels. The data reported to EPA 

on emissions from fuel production vary across fuel types and is much more detailed for gasoline 

production. At the present time, it would be difficult to represent emissions from energy 

generation on a national label in a way that is both useful and accurate for consumers, given 

regional variations, how generation within regions is dispatched, and access to green power 

purchases. 

 Therefore, EPA and NHTSA are proposing that the label should limit itself to tailpipe 

only emissions (clearly identified as such) and include a more complete discussion on energy 

generation and lifecycle analysis on the webpage. We believe that this approach will prove 

sufficiently informative to consumers. It also allows us the opportunity to provide a fuller 

3

 See http://www.eia.doe.gov/energyexplained/index.cfm?page=electricity_in_the_united_states for an overview of the national U.S. electric 

power industry net generation by fuel type.

4

 Regional values could be provided on a web site. EPA has a website (http://www.epa.gov/cleanenergy/energy-and-you/how-clean.html) on 

which consumers can enter their zip code and find out what fuel mix is used to produce the electricity they use.
Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

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discussion of GHG emissions associated with energy generation for alternative vehicles, as well 

as emissions from fuel production (gasoline and biofuels). For example, a website could provide 

calculator tools that could reflect regional variations in the GHG emissions associated with 

electricity generation as well as use national averages. A website could also provide information 

on the projected fuel lifecycle impacts associated with biofuels. The website could be updated 

over time as the mix of electricity fuel sources and biofuels changes. This approach could help 

the consumer understand over the lifetime of their vehicles how their electricity generation 

emissions impacts might be changing. 

The agencies acknowledge that more consumers will look at the label than at the website, 

and that a “0” figure for GHG emissions might prove confusing to some consumers. While 

accurate and more complete information will be provided on the website, putting 0 grams 

CO2/mile on the label may lead some consumers to misperceive that driving their EV does not 

contribute to GHG emissions. 

At this point in time, any effort to provide complete lifecycle information for fuels on the 

label could well produce undue confusion. A label that clearly presents tailpipe emissions 

appears to be the best available way to combine accuracy and disclosure, so long as fuller 

information is available on the website. The agencies believe that even though many consumers 

will not visit the website, it will be used by many groups and organizations, and as a result, the 

information that it provides will be made available and used in the marketplace. Similar 

information will also be provided in the owner’s manual, per the requirements of EISA, for 

alternative fuel vehicles, which will describe the capability and benefits of using alternative 

fuels, including the renewable nature and environmental benefits of such fuels (see 49 USC 

32908(g)). We seek comment on our current view that the web is the better place, compared to 

the label, to address the complex issues associated with emissions associated with electricity 

generation and lifecycle emissions more generally. 

We invite both general and particular comments on the proposed approach. For example, 

we encourage commenters to be as specific as possible with any recommendations on how to 

address fuel combustion/electricity generation GHG emissions on the website. If information on 

these emissions is to be provided on a website, exactly what information? The agencies 

specifically invite comment on how to address fuel combustion emissions associated with the 

electricity used to power the advanced technology vehicles starting to enter commerce, electric 

vehicle, and plug-in hybrid vehicles. The agencies also invite comment on how to address full 

GHG emissions from biofuels on a website. Should emissions be identified specifically for the 

emissions associated with the combustion of fuel to produce electricity? Should such emissions 

be determined on a regional or a national basis? Should these emissions be provided as a relative 

comparison to a gasoline or diesel fuel, the current predominant fuels? 
Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

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o 

For the convenience of commenters, we have prepared the table below as an illustrative 

example of one simplified way that some lifecycle emissions information related to electricity 

production could be accounted for on a website, based on certain assumptions.5 It is important 

to note that for comparison purposes, the agencies would need to develop methodologies t

compare upstream emissions impacts from all other fuels as well, including diesel, renewable 

fuels, and natural gas. Consistent with the discussion above, it is important to emphasize that the 

tailpipe + lifecycle values in the table below are based on 2005 national average electricity GHG 

emissions, and could be very different for certain regions of the country today and for the nation 

in the future if there are major changes in the mix of methods used to generate electricity or in 

the GHG emissions associated with its generation. 

Proposal--TailpipeOnly Tailpipe + Lifecycle 

Vehicle CO2/mile CO2/mile 

Nissan Leaf EV* 0 197 

Chevrolet Volt PHEV* 89 210 

Toyota Prius PHEV* 133 217 

Toyota Prius HEV 178 224 

Honda Civic HEV 212 266 

Honda Insight HEV 217 273 

Ford Fusion HEV 228 287 

*Based on industry averages 

In general, for purposes of providing information on the web, the agencies invite 

comment on the appropriate metrics to use and the specific suggestions for content and format, if 

appropriate. The agencies also request comment on which web resources it should prioritize for 

development that would provide the most useful information to consumers. 

                                                           

5

    The key assumptions underlying the illustrative numbers in the right-hand column are that:EV and PHEVs all assumed to use 200 Watt-hours 

per mile when operating on electricity over the EPA test and assuming a 30% range (43% electricity consumption) shortfall from test to road. 

• PHEV 1 assumed to operate on electricity 50% of the time. 

• PHEV 2 assumed to operate on electricity 25% of the time. 

• Uses 2005 nationwide average value of 0.642 grams of GHG per Watt-hour at powerplant (adjusted to include GHG emissions from 

feedstock extraction, transportation, and processing as well) from MY2012-2016 light-duty vehicle GHG final rule (75 Federal 

Register 25437). 

• Assumes typical 7% electricity grid transmission losses. 

• Uses 2250 grams GHG per gallon of gasoline.
Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

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With respect to the label itself, the agencies are also requesting comment on alternative 

options for the label that, in addition to presenting tailpipe emissions, refer to or identify in some 

manner the emissions associated with the lifecycle of the fuel. Under one version of this 

alternative that is under serious consideration, similar to a co-proposal, the EV label would 

continue to reflect the "0" CO2g/mile number currently displayed on the co-proposed labels 

(Figures III-2, III-10), but the label would be modified by adding either a symbol or an asterisk 

and explanatory text which states, "The only C02 emissions are from electricity generation." 

Likewise, the agencies would modify the co-proposed PHEV labels (Figures III-3, III-6, III-1, 

III-12) inserting either a symbol or asterisk next to the current CO2g/mile number displayed with 

the following explanatory text, “Does not include CO2 from electricity generation.” This 

alternative might provide more accuracy and clarity for purchasers by more explicitly indicating 

that the CO2 emissions from generation of electricity are not reflected in the CO2 numbers on 

the label. Under this alternative, FFV labels (for FFV vehicles only) would continue to reflect 

the gasoline only CO2g/mile number currently displayed on the co-proposed labels (Figures III-8 

and III-14), but the label (for FFVs only) would be modified by adding either a symbol or an 

asterisk and explanatory text that might state, “The CO2 emissions listed here are from gasoline 

combustion only. They do not reflect the use of renewable biofuels.” The agencies request 

comment on this alternative option. 

The agencies are also giving consideration to an approach that in addition to the tailpipe 

emissions, includes information on upstream emissions on the label. On an average basis, GHG 

emissions are a function of MPG or KwH per mile, and thus could in principle be calculated, and 

if a full or nearly full accounting could be provided in a clear and intelligible form, there would 

be advantages to providing it on the label to consumers, in addition to providing the tailpipe 

emissions data. Therefore, the agencies invite comment on the feasibility and usefulness of an 

alternative approach that in addition to identifying tailpipe emissions, would include a separate 

value for upstream emissions on the label as well as on the website. 

In particular, the agencies invite comment on what type of information should be 

considered as “upstream,” and whether a label including the upstream emissions could be based 

on national averages. The agencies might consider using assumptions that would be similar to 

the national averages used to calculate fuel costs for electric vehicles (12 cents per KW hour), 

fuel price on the label ($2.80), and the number of vehicle miles travelled (15,000); however, the 

number of additional assumptions that agencies would need to make may be substantial. These 

include assumptions about the overall impact on electric car recharging on the grid mix, which 

would include making assumptions about the time-of-day distribution of recharging and the 

subsequent impacts on the base and peak load electricity generation as well as recognition of 

regional variability and potential changes in the electricity generation fleet. A relevant source 
Summary of Interagency Working Comments Received on Draft Rule under EO 12866 Review.  Subject to

Further Policy Review

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for this type of information may be the Energy Information Administration (EIA), which 

provides estimates of the future electricity generation mix, so there may be some basis for 

estimating future GHG emissions based on current state and federal policies; but these estimates 

will inevitably rest on some uncertain assumptions. The same type of analysis (national averages 

for feedstocks and fuel production) would need to be developed and equivalent assumptions 

made related to upstream emissions from gasoline and diesel production as well as renewable 

fuels, natural gas, and hydrogen. The agencies invite comments on whether and how the 

possible inclusion of upstream emissions information on the label might affect other elements of 

the label such as design, format, presentation of the various ratings and other information as well 

as the ranking of vehicles on the label. 

The agencies also recognize that notwithstanding the many challenges, a potential 

advantage of including upstream emissions on the label is that consumers may be able to 

compare different EVs on this dimension, as some will require more energy per mile traveled 

than others, and may be able to compare EVs, PHEVs, and fueled vehicles on this dimension as 

well. Regardless of what would be presented on the label, the agencies will continue to provide 

detailed information about the lifecycle GHG impacts of different vehicles on the website in a 

way that may provide a better way for individuals to take their region, driving habits, and other 

specific factors into account in their purchase decisions. 

In view of the many assumptions the agencies would need to make to conduct such an 

analysis, we emphasize that this alternative would have to overcome several serious challenges. 

We ask for comment on whether and how each of those challenges, outlined above, could be 

addressed if considered for a label.