Analysis of the Effect of ZeroEmission Vehicle Policies: StateLevel Incentives and the 

California Zero-Emission Vehicle 

Regulations 

September 2017

Independent Statistics & Analysis

www.eia.gov

U.S. Department of Energy

Washington, DC 20585
U.S. Energy Information Administration | Improving the Quality and Scope of EIA Data i

This report was prepared by the U.S. Energy Information Administration (EIA), the statistical and 

analytical agency within the U.S. Department of Energy. By law, EIA’s data, analyses, and forecasts are 

independent of approval by any other officer or employee of the United States Government. The views 

in this report therefore should not be construed as representing those of the U.S. Department of Energy 

or other federal agencies.
September 2017

U.S. Energy Information Administration | Improving the Quality and Scope of EIA Data 1

Introduction

The U.S. Energy Information Administration (EIA) contracted with Leidos to analyze the effect of 

California zero-emission vehicle regulations (ZEVR) and state-level incentives on zero-emission and plugin hybrid vehicle sales.

Leidos worked to review the effect of state-level incentives by:

 Conducting a review on the available incentives on zero-emission vehicles and related 

transitional vehicle types such has plug-in hybrid electric vehicles

 Quantifying the effective monetary value of these different incentives

 Evaluating the combined values of these incentives in each state on an example sale of a Nissan 

Leaf and Chevrolet Volt

Leidos worked to project the effect of the California ZEVR by:

 Reviewing California’s mid-term review, credit reports from adopting states, and historical sales 

trends and credit balances

 Developing an Excel based model to project sales under potential scenarios and compliance 

pathways through 2025 based on AEO2017 projections

Recognizing that historical data for adoption of these vehicles is limited, the number and type of 

available zero-emission and plug-in hybrid electric vehicle models is increasing, and capabilities are 

changing rapidly, Leidos recommended further study as more data become available. Suggested further 

study includes:

 Expanding the ZEVR projections to include hydrogen fuel cell vehicles

 Improving the granularity of the state level analysis to a monthly level

EIA plans to use this report to improve projections for sales of these vehicle types and modeling 

methodology for the ZEVR in the Annual Energy Outlook 2018. Example modeling improvements will 

include credit banking and spending, and the Section 177 state alternative compliance pathway. 

Through this added capability, EIA can examine various compliance pathways through different bank 

utilization rates and sales strategies. 
September 2017

U.S. Energy Information Administration | Improving the Quality and Scope of EIA Data 2

Appendix A
 

 

 

 

Analysis of the Effect of Zero-Emission Vehicle Policies: 

State-Level Incentives and the California Zero Emission Vehicle 

Regulations 

Final Draft

Submitted:

April 30, 2017

Delma Bratvold

Matthew Cleaver
i

Table of Contents

List of Abbreviations .................................................................................................................................... iii

1 Introduction ..........................................................................................................................................1

1.1 Objective and Approach................................................................................................................1

1.2 Policy Goals that Support ZEV and PHEV Adoption ......................................................................1

2 State ZEV Incentive Analysis .................................................................................................................2

2.1 Valuation Methods .......................................................................................................................2

2.1.1 Rebates .................................................................................................................................3

2.1.2 Tax Credits.............................................................................................................................4

2.1.3 State Sales Tax Exemption ....................................................................................................4

2.1.4 Free Parking ..........................................................................................................................4

2.1.5 Inspection Exemption ...........................................................................................................5

2.1.6 High Occupancy Vehicle (HOV) Lane Access.........................................................................5

2.1.7 Electric Vehicle Supply Equipment (EVSE) Incentives...........................................................7

2.2 Valuation Results ..........................................................................................................................7

2.3 Incentive Impact on Prices............................................................................................................8

2.4 Incentive Impact on Sales...........................................................................................................11

3 Sales Projections in Zero Emission Vehicle Regulation (ZEVR) States ................................................15

3.1 Introduction to the ZEVR ............................................................................................................16

3.2 Credit Types and Value Estimation .............................................................................................16

3.2.1 Types of Credit-Earning Vehicles ........................................................................................16

3.2.2 Credit per Vehicle Rules......................................................................................................18

3.2.3 Average ZEV and PHEV Range.............................................................................................18

3.2.4 Credit Travel........................................................................................................................21

3.2.5 Other Types of Credits........................................................................................................21

3.3 Credit Requirements...................................................................................................................22

3.3.1 Basic Path............................................................................................................................22

3.3.2 Optional S177 Path .............................................................................................................23

3.3.3 Estimated Requirements through 2025..............................................................................23

3.4 Credit Reports, Balances, and Size Classes.................................................................................25

3.4.1 Available Credit Reports......................................................................................................25

3.4.2 Credit Balance Differences Among the States....................................................................25
ii

3.4.3 Estimation of Credit Balances through 2017 ......................................................................27

3.4.4 Manufacturer Size Classes and Market Share ....................................................................29

3.5 Sales through 2017 .....................................................................................................................31

3.5.1 Sales by State ......................................................................................................................31

3.5.2 ZEV to PHEV Sales Ratio......................................................................................................31

3.6 Sales Estimation for 2018 through 2025.....................................................................................33

3.6.1 Accounting for Risk Mitigation............................................................................................33

3.6.2 Base Assumptions...............................................................................................................33

3.6.3 Sales Estimation Method for 2018 to 2025 ........................................................................34

3.6.4 Sales Forecast with Base Assumptions...............................................................................36

3.6.5 Effect of East Pool Redistribution on Sales Forecast ..........................................................38

3.6.6 Effect of ZEV Share of the ZP Market on Sales Forecast.....................................................43

3.6.7 Collective Scenarios ............................................................................................................44

Appendix – Light-Duty Vehicle Sales Forecast............................................................................................47
iii

List of Abbreviations

ARB – Air Resources Board of the California Environmental Protection Agency

ATPZEV -- Advances technology partial zero emission vehicle

CBCR – Ratio of total 2025 credit balance to total 2026 credit requirement

CCR – California Code of Regulations

EVSE -- Electric vehicle supply equipment

FCEV – Fuel cell electric vehicle

HOV -- High-occupancy vehicle

ICCT -- International Council on Clean Transportation

IVM – Intermediate-size vehicle manufacturer

KBB – Kelly Blue Book

LDV – Light-duty vehicle

LVM – Large-size vehicle manufacturer

MY – Model year

NEV – Neighborhood electric vehicle

PHEV – Plug-in hybrid electric vehicle

PZEV -- Partial zero emission vehicle

S177 – Section 177 of the Clean Air Act

SVM -- Small-size vehicle manufacturer

TZEV – Transitional zero emission vehicle

VTTS -- Value of travel time savings

YoY – Year-on-year

ZEV – Zero emission vehicle

ZEVR – California zero emission vehicle regulations

ZP – Combined ZEVs and PHEVs
1

1 Introduction

1.1 Objective and Approach 

The objective of this report is to assess the effect of state-level policies on the sales of zero-emission 

vehicles (ZEVs) and plug-in hybrid electric vehicles (PHEVs). Two analysis approaches are applied. The 

first approach assesses the potential effect of state-level incentives through quantification of the 

monetary value of ZEV and PHEV incentives and comparison of these values to state-level sales of these 

vehicles. The second approach focuses on the effect of California ZEV regulations on sales in California 

and in the nine other states that have adopted these regulations. ZEV and PHEV sales in these ten states 

are projected through 2025 under a variety of scenarios based on the regulations and associated historic 

trends in sales and credit balances earned under these regulations. 

1.2 Policy Goals that Support ZEV and PHEV Adoption 

Key multi-state drivers of ZEV and PHEV adoption are the California Zero Emission Vehicle Regulations,1

abbreviated as the “ZEVR” in this report. These regulations are part of California’s Advanced Clean Cars 

(ACC) program, and were established with the intent to support and accelerate the numbers of PHEVs

and ZEVs in California. Under Section 177 of the Clean Air Act, other states are given the option to adopt 

California's standards to help achieve federal air quality requirements. Nine states have fully adopted 

the ZEVR: Connecticut, Massachusetts, Maryland, Maine, New Jersey, New York, Oregon, Rhode Island, 

and Vermont. Together, the ten ZEVR states represent more than a quarter of total annual light-duty 

vehicle sales in the United States. 

The adoption of ZEVs and PHEVs provides a means to achieve policy goals to reduce emissions from the 

transportation sector. An example of ZEV policies beyond the ZEVR that support emissions reductions is 

seen in California Executive Order B-16-2012 (March 23, 2012), which establishes a target to reduce 

Greenhouse Gas (GHG) emissions from transportation by 80% in 2050 compared to 1990 levels. This 

order also outlines measures to support ZEV deployment and directs state agencies to establish 

benchmarks to achieve no less than 1.5 million “ZEVs” on the road by 2025, where “ZEVs” includes both 

ZEVs and PHEVs. California Executive Order B-30-2015 further establishes an interim statewide target to 

reduce GHG by 40% in 2030 compared to 1990 levels. These targets are reinforced in legislation 

(Chapter 547, Statutes of 2015, Senate Bill 350, De Leon), which concluded that the GHG reduction goals 

in the Executive Orders will require widespread transportation electrification, and the Charge Ahead 

California Initiative, Senate Bill 1275 (De León, Chapter 530, Statutes of 2014), which sets a target to 

place in service 1 million ZEVs and near ZEVs by January 1, 2023. 

Beyond California, a collective target of at least 3.3 million ZEVs and PHEVs on the road by 2025 was 

agreed to in the State ZEV Programs Memorandum of Understanding (MOU).2 The MOU was signed in 

2013 by the governors of California and seven of the nine other states that have adopted the ZEVR (i.e., 

all but Maine and New Jersey). The MOU states that “accelerating the ZEV market is a critical strategy 

for achieving our goals to reduce transportation-related air pollution, including criteria air pollutants, 

mobile source air toxics and GHGs, enhance energy diversity, save consumers money, and promote 

 

1 Title 13 of the California Code of Regulation (CCR), Sections 1962.1 and 1962.2

2 2013. State Zero Emission Vehicle Programs Memorandum of Understanding. 

http://www.nescaum.org/documents/zev-mou-8-governors-signed-20131024.pdf/
2

economic growth.” This was followed by the Multi-State ZEV Action Plan,

3 which lists eleven actions to 

encourage the ZEV market through facilitating both the purchase and lease of vehicles, and planning and 

investing in ZEV infrastructure. The partner states have subsequently developed these actions to varying 

extents. State-level actions to encourage ZEV adoption are also found in many states that are not part of 

the MOU. 

The ZEVR encourages ZEV and near-ZEV sales through a “negative” incentive in the form of monetary 

penalties for manufacturers that fail to obtain the required level of ZEV and near-ZEV sales credits. 

Other ZEV incentives are generally positive incentives that reward the purchase or use of ZEVs and 

PHEVs. Many of these positive incentives, as taken by both ZEVR states and other states, are described 

in the following section. 

2 State ZEV Incentive Analysis

The purpose of this analysis is to assess the impact of state government incentives on ZEV and PHEV 

price, value, and sales. Many states offer incentives to promote ZEV and PHEV adoption. These 

incentives include financial subsidies, such as rebates, tax exemptions, grants, and loans, as well as 

incentives for vehicle use, such as free parking, high occupancy vehicle (HOV) lane access, and emission 

inspection exemptions. There are also incentives that target electric vehicle supply equipment (EVSE) 

such as rebates and tax credits for installing charging equipment. The incentives target various endusers including individual vehicle owners, vehicle fleets, vehicle and parts manufacturers, and 

alternative fuel producers. Most incentives are available to a broad spectrum of end-users, including 

both individuals and fleets. 

This analysis applies methodologies to quantify the monetary value of statewide ZEV and PHEV 

incentives that target both individual and fleet owners. The more limited number of incentives that only 

target fleets are not included. The assessed incentives include the technology categories of all-electric 

(battery) vehicles, plug-in hybrid electric vehicles, and hydrogen fuel cell vehicles. The analysis also 

includes incentives for the purchase of home electric vehicle supply equipment (EVSE). 

For the current analysis, methods for the monetization of specific consumer-oriented U.S. state-level 

incentives, developed in a 2014 white paper by the International Council on Clean Transportation (ICCT 

White Paper),4 are applied and modified where appropriate.

2.1 Valuation Methods

The primary source for identification of state-level incentives in this analysis was the U.S. Department of 

Energy Alternative Fuels Data Center (AFDC) database.5 Additional sources were used to obtain more 

detailed descriptions of incentives as needed, including individual state level departments of 

environment and transportation. 

This analysis includes 54 individual state-level direct incentives offered by 30 states as of December 

2016. These include 19 incentives for vehicle purchase or lease, including rebates and tax credits, and 27 

incentives for vehicle use, including HOV lane exemptions, state vehicle inspection exemptions, and free 

public parking. The analysis also includes 8 incentives that offset the cost of installing home EVSE. An 

 

3 2014. Multi-State Zev Action Plan. http://www.mass.gov/eea/docs/dep/air/community/zevplan14.pdf

4

Jin, L., Searle, S., and Lutsey, N. (2014). Evaluation of State-Level U.S. Electric Vehicle Incentives. ICCT White 

Paper. Retrieved December 1, 2016, from http://www.theicct.org/sites/default/files/publications/ICCT_state-EVincentives_20141030.pdf

5 U.S. Department of Energy Alternative Fuels Data Center. 2016. http://www.afdc.energy.gov/
3

additional type of incentive, free public electric vehicle charging, was not quantified as it was 

determined not to be a significant contributor to state-level incentive value. While a study published in 

2013 suggests the majority of vehicle charging is done at home or at work,6 which would limit the value 

of free public charging, these patterns may be changing, particularly with the development of fast 

recharging. 

In many cases the value of an incentive, particularly purchase incentives, is calculated based on vehicle 

characteristics such as technology type, battery capacity, range, or a combination of characteristics. In 

order to provide a consistent comparison across states and vehicle types, incentives for ZEVs are 

estimated based on the purchase of a model year 2016 (MY2016) Nissan Leaf SV and incentives for 

PHEVs on the purchase of a MY2016 Chevrolet Volt. The relevant characteristics for these vehicles are 

shown in Table 1 below.

Table 1. Characteristics of sample vehicles

While many of the reviewed incentives applied to both ZEVs and PHEVs, there were some exceptions. 

For example, South Carolina offered an income tax credit that only applied to PHEV purchases, and a 

sales tax exemption that only applied to hydrogen fuel cell vehicles. Several states had incentives that 

only applied to ZEVs, most of which were emission test exemptions. New Jersey offered a sales and use 

tax exemption incentive to only ZEVs. 

The sections below describe the methodology for quantifying each type of incentive.

2.1.1 Rebates

Nine states offered monetary rebates for the purchase or lease of a ZEV or PHEV. Rebate amounts 

ranged from $1,500 for the purchase of a PHEV in Delaware to $3,500 for the purchase of a ZEV, also in 

Delaware. A $3,500 rebate was offered in Texas, although it applied to the replacement of a higher 

emissions vehicle with any type of cleaner vehicle, including conventional propulsion systems. Further, 

the Texas incentive limited eligibility on the basis of income and age of the replaced vehicle. 

Nonetheless, it is included in this analysis.

Some states allow purchasers to individually submit rebate applications. In these cases, the rebate is 

received as a paper check or a direct deposit with a delivery time ranging from 10 days to six weeks after 

application approval. Other states, such as Texas, require the dealer to file the rebate application. In 

these cases, the dealer receives the rebate on behalf of the purchaser and subtracts the rebate amount 

from the sale price of the vehicle or from the monthly payments. Still other states allow the purchaser 

to choose whether they receive the rebate individually or request the rebate through the dealer. One 

 

6

Idaho National Laboratory. Plugged In: How Americans Charge Their Electric Vehicles. Findings from the largest 

plug-in electric vehicle infrastructure demonstration in the world. 2013. 

https://avt.inl.gov/sites/default/files/pdf/arra/SummaryReport.pdf
4

state, California, calculates rebate amounts based on the purchaser’s gross annual income in addition to 

vehicle characteristics, and purchasers are not eligible for rebates if their incomes are above the 

thresholds set by the program.7For the purpose of this analysis, the incentive value was quantified 

assuming a single filer with a gross annual income less than $150,000, which would be eligible for the 

rebate. 

2.1.2 Tax Credits

Five states, Colorado, Louisiana, Maryland, South Carolina, and Utah, offered tax credits for the 

purchase or lease of a ZEV or PHEV. As noted above, South Carolina was the only state to offer a tax 

credit only for PHEVs. Similar to the rebate programs, tax credit amounts varied depending on vehicle 

characteristics. However, an income tax credit reduces a purchaser’s tax liability on a dollar-for-dollar 

basis. Therefore, depending on the purchaser’s individual tax liability, they may not receive the full tax 

credit amount. Two states, Colorado and Louisiana, offered refundable income tax credits. This means if 

the amount of the tax credit exceeds the purchaser’s tax liability, the additional amount will be refunded 

to the tax payer. Maryland offered an excise tax credit that allowed a credit for the full amount of the 

excise tax imposed on qualified ZEVs and PHEVs. In the remaining states with tax credits (South Carolina 

and Utah), the full tax credit would have been received for at least a median household income and 

average tax deduction in those states.8For the purpose of this analysis, all values for tax credits are 

shown as the maximum possible value. Tax credit amounts ranged from $1,000 for the purchase or lease 

of a PHEV in Utah to $6,000 towards the purchase of a ZEV in Colorado. The vehicle characteristics and 

formulas for calculating tax credit amounts varied by state. For example, Colorado’s tax credit is 

calculated as the actual cost incurred to purchase or lease the vehicle multiplied by the battery capacity 

and divided by 100, not to exceed $6,000. Using this formula and cap, many PHEVs and ZEVs would 

qualify for the maximum credit.

2.1.3 State Sales Tax Exemption

Three states, New Jersey, South Carolina, and Washington, and the District of Columbia, exempted ZEVs 

and/or PHEVs from state sales tax. New Jersey exempted only ZEVs and South Carolina only exempted 

hydrogen fuel cell vehicles. Sales tax exemption incentive values varied based on vehicle price and the 

amount of sales tax that would have been applied without the incentive. This incentive is calculated by 

multiplying the state sales tax percentage by the purchase price of a ZEV or PHEV. 

2.1.4 Free Parking

Three states, Arizona, Hawaii, and Nevada, offered free parking for drivers of ZEVs and PHEVs. Arizona’s 

free parking program only applies to designated carpool operator parking spaces, as such, it is not 

included in this analysis because it is thought to benefit a relatively small number of users. The benefits 

of parking incentives are assumed to be limited to major metropolitan areas, which is where most public 

street parking is utilized. For valuation in this analysis, Honolulu is used to represent metropolitan areas 

in Hawaii, and Las Vegas and Reno is used to represent metropolitan areas in Nevada. The value of the 

free parking incentive is calculated as follows:

Vs = Rs × Ps × H × Y

 

7 The income cap does not apply to the purchase of fuel cell electric vehicles.

8 Median Income from U.S. Census Bureau. State taxes calculated using 

http://taxformcalculator.com/state_tax.html. Average tax deduction from Wall Street Journal (2010) 

https://www.wsj.com/articles/SB10001424127887323852904578128950616756728
5

Where:

Vs = Value of parking incentive for state s

Rs = Average hourly parking rate for state s

Ps = Percentage of population that is metropolitan for state s

H = Average hours parked per year 

Y = Years of vehicle ownership

The average hourly parking rate is estimated based on city-specific rates of public metered parking 

spaces as reported at Parkopedia.com. The average hours parked per year is calculated with the 

assumed use of 5 hours of public parking per week, which is the same assumption used in the ICCT 

White Paper. The original source of this assumption is a 2009 Honolulu parking survey. No studies were 

found with more recent data on average public parking time in metropolitan areas. The average length 

of vehicle ownership is assumed to be five years based on average ownership of new light-duty vehicles 

as reported by IHS Automotive.9

Although the average parking fees in both states were similar ($0.75 per hour in Honolulu and $1.00 per 

hour in Las Vegas and Reno), the free parking incentive in Hawaii is more than twice as valuable on a 

statewide basis than in Nevada primarily because a larger fraction of the population of Hawaii lives in 

metropolitan areas.

2.1.5 Inspection Exemption

As of December 2016, 33 states and the District of Columbia required vehicle emission inspections.10 Of 

these, 13 states exempted ZEVs from the inspection program. Only one of these states, North Carolina, 

also exempted PHEVs. The benefits of this incentive include the value of the avoided inspection fees and 

the value of the time saved by avoiding inspection. Both of these benefits are summed over the length 

of vehicle ownership. However, many states delay the requirement for emissions inspection for the first 

three to four years after the model year and this delay is included in the valuation for this incentive. 

After the delay period, if any, most state inspection programs require annual or bi-annual inspections 

with fees ranging from $20 to $40. The average time to complete an inspection is assumed to be 30 

minutes. The value of this incentive did not vary widely across states and is relatively small compared to 

other incentives offered.

2.1.6 High Occupancy Vehicle (HOV) Lane Access

Twelve states offered ZEVs and PHEVs access to HOV lanes regardless of the number of passengers in 

the vehicle. The primary benefit of this incentive is the time saved by avoiding congestion on non-HOV 

travel lanes. While travel time savings may also reduce vehicle operating costs, these costs are assumed 

to be marginal and are not included in the analysis. The value of HOV access is estimated as the product 

of the fraction of the state population living in areas with HOV lanes, the Value of Travel Time Savings 

(VTTS), and Time Savings. Each of these three factors is further described below.

The fraction of the state population living in areas with HOV lanes is estimated with the assumption that 

HOV lanes are only in major metropolitan areas. As such, the fraction of the population that benefit 

 

9 Business Wire. July 29, 2015. IHS Automotive - Length Of Vehicle Ownership 2005-15 (Graphic: Business Wire).

The Street. https://www.thestreet.com/story/13235449/1/ihs-automotive--length-of-vehicle-ownership-2005-15-

graphic-business-wire.html

10 American Automobile Association. 2016. Digest of Motor Laws. Emissions Inspection. 

http://drivinglaws.aaa.com/tag/emissions-inspection/
6

from this incentive is the ratio of the state’s metropolitan population to its total population. Population 

data for major metropolitan areas for each state were obtained from the U.S. Census Bureau. 

VTTS is calculated following the U.S. Department of Transportation’s (DOT) Guidance on Valuation of 

Travel Time in Economic Analysis.

11 Using this method, VTTS is the sum of local and intercity travel time 

savings, where each of these is the product of the following:

 Median hourly household income – median annual household income divided by 2080 workhours per year. State median incomes used in this analysis are from the U.S. Census Bureau.

 Value of personal travel time – The DOT estimates the value of personal travel time as a 

percentage of the median hourly household income where intercity travel time is valued at 70% 

of the hourly income and local travel is valued at 50% of the hourly income. This distinction is 

based on the assumption that the value of travel time increases with distance.

 Travel type proportion – each type of travel, local and intercity, is assigned a proportion of total 

travel. Considering ZEV range limitations, it was assumed that 70% of ZEV driving time is local 

travel and 30% is intercity travel.

Time Savings is estimated as the product of travel time to work, the ratio of peak travel time to free-flow 

travel time, and an HOV relief factor as shown in the following equation:

Ss = Ts × Rs × F

Where:

Ss = Time savings for state s

Ts = Travel time to work for state s

Rs = Ratio of peak travel time to free-flow travel time for state s

F = HOV relief factor

Travel time to work is from the U.S. Census Bureau’s American Community Survey (ACS) Mean Travel 

Time to Work12 in which travel time to work refers to total minutes to and from work per week. The 

ratio of peak-period travel time13 to free-flow travel time is the Travel Time Index as reported in the DOT 

Federal Highway Administration’s Urban Congestion Report14 where HOV lane travel is assumed to be 

the same as free flow travel. The HOV Relief Factor is a rough approximation to account for the fact that 

only a fraction of work travel time is relieved by HOV lanes. This analysis used a factor of 20% for all 

metropolitan areas. This factor may be modified as more data on HOV lane utilization is identified. 

The value of HOV lane access was much higher in states that have large metropolitan areas with longer 

travel times and greater differences in Travel Time Index. For example, the value of this incentive in 

California, New York, and Hawaii was more than double that of most other states that offered this 

incentive. 

 

11 US Department of Transportation. Revised Departmental Guidance on Valuation of Travel Time in Economic 

Analysis. https://www.transportation.gov/sites/dot.dev/files/docs/vot_guidance_092811c.pdf.

12 U.S. Census Bureau. Mean Travel Time to Work. https://www.census.gov/quickfacts/meta/long_LFE305214.htm. 

13 Peak period travel time is based on weekday morning and evening peak periods of 6:00 a.m. to 9:00 a.m. and 

4:00 p.m. to 7:00 p.m., respectively.

14 DOT Federal Highway Administration. Travel Time Index. 

http://www.ops.fhwa.dot.gov/perf_measurement/ucr/documentation.htm. 
7

2.1.7 Electric Vehicle Supply Equipment (EVSE) Incentives

Eight states offered rebates or tax credits for the purchase and installation of residential EVSE. The value 

of this incentive is based on the purchase and installation of Level 2 EVSE, which is assumed to be a 

typical residential installation. Level 2 equipment provides charging through a dedicated 240V AC plug 

and usually requires professional installation. 

According to a 2014 study by the Rocky Mountain Institute, the cost of a typical home Level 2 EVSE 

installation is approximately $1,200.15 The cost of the charging station equipment itself accounts for 

about half of this cost. Professional installation by an electrician accounts for the remaining cost, which 

typically includes the cost of materials and labor necessary to install a 240V circuit from an existing

breaker panel. 

Depending on the incentive structure, the value of EVSE incentives is calculated as either the fixed 

amount of the offered rebate or tax credit, or the offered percentage of the installation cost. Some 

examples of EVSE incentives include a $500 rebate in Delaware for installation of residential Level 2 

charging stations, and tax credit in the District of Columbia for 50% of the costs for purchase and 

installation of residential EVSE, with a maximum credit of $1,000. 

2.2 Valuation Results

Figure 1 shows the estimated value of state level ZEV incentives for the 20 states with the highest 

combined ZEV incentive values as of December 2016 with ZEVR states indicated by a box around the 

state name. Two ZEVR states, Maine and Vermont, did not offer consumer-oriented incentives as of 

December 2016 and are therefore not shown on this chart. 

Figure 1. Value of state level ZEV incentives

 

15 The Rocky Mountain Institute. Pulling Back the Veil on EV Charging Station Costs. 

http://blog.rmi.org/blog_2014_04_29_pulling_back_the_veil_on_ev_charging_station_costs. 
8

Rebates and tax credits made up the largest share of incentive value across states. Colorado had the 

highest direct incentive with a $6,000 tax credit offered for purchasing ZEVs and most PHEVs. State sales 

tax exemptions also accounted for a large share of incentive value. 

Figure 2 shows the estimated value of state-level PHEV incentives for the 20 states with the highest 

combined PHEV incentive values as of December 2016 with ZEVR states indicated by a box around the 

state name. As with ZEV incentives, rebates, tax credits, and sales tax exemptions made up the majority 

of incentive value for PHEVs. New Jersey, a ZEVR state, had a sales tax exemption that only applied to 

ZEVs and therefore does not appear in this chart.

Figure 2. Value of state level PHEV incentives

2.3 Incentive Impact on Prices

The impact of incentives on vehicle price was assessed by calculating the average price for a MY2016 

Nissan Leaf (a ZEV model) and a MY2016 Chevrolet Volt (a PHEV model), including registration, taxes, 

and direct monetary incentives for purchases in each state. The price that a consumer ultimately pays 

for a vehicle varies from state to state and even from dealer to dealer. The manufacturer suggested 

retail price (MSRP), or the price the consumer sees on the “window sticker” of a vehicle, does not show 

the variety of discounts typically offered by manufacturers to dealers or customers. The two most 

common discounts offered to dealers are Dealer Holdback and Dealer Cash Incentives. The Dealer 

Holdback is a percentage of the invoice price a manufacturer pays to the dealer. The Dealer Holdback is 

designed to supplement a dealer's cash flow and offset variable expenses. Edmunds estimates that a 

typical holdback is approximately two percent of the total vehicle invoice, however, it varies across 

manufacturers and can range from zero to three percent.16 Dealer Cash Incentives are provided by 

manufactures on a regional basis, often to generate sales on specific models. These incentives are 

 

16 Reed, Philip. July 30, 2013. Dealer holdback, what it is and how it works. Edmunds. 

https://www.edmunds.com/car-buying/dealer-holdback/
9

proprietary information, as such, there is very little data on the actual amounts that manufacturers offer 

to dealers in the form of holdbacks and cash incentives. In addition, the sticker price does not reflect tax, 

title, license, or registration fees. These fees vary from state to state and can collectively add a 

significant amount to the final price of the vehicle. 

The average vehicle sales price for a MY2016 vehicle in metropolitan areas in each state was obtained 

from Kelley Blue Book (KBB).17 The KBB sales prices are the average of actual transactions in a region and 

include the sticker price and destination fee, but do not include title, registration, and other fees or 

incentives. State sales tax and dealer documentation fees from Edmunds,18 as well as state registration 

fees from the National Conference of State Legislatures19 were added to the average vehicle sales prices 

to calculate the total vehicle price to the consumer before incentives. 

Average vehicle prices before fees did not vary significantly from state to state for either vehicle. The 

nationwide average sales price for a MY2016 Nissan Leaf SV, including destination charge but not 

including taxes and fees, was $32,398. The average price for a MY2016 Chevrolet Volt was $31,371. The 

highest price for the Nissan Leaf before taxes and fees was in Hawaii, at $32,681, and the lowest price 

was in Georgia, at $31,632. The highest price before taxes for the Chevrolet Volt was in Rhode Island, at 

$31,732, and the lowest was in Georgia at $30,702. Taxes were the largest and most highly variable 

additional cost with a nationwide average tax of $2,332. Taxes ranged from over $3,800 in Arkansas to 

under $1,500 in Hawaii. Four states, Delaware, New Hampshire, Montana, and Oregon, do not charge 

sales tax on vehicles as part of state law. Other states, including New Jersey, South Carolina, 

Washington, and the District of Columbia, offered incentives that exempt ZEV and PHEV purchasers 

from sales tax. With the addition of taxes and fees, Arizona had the highest average price for both for 

the Nissan Leaf, at $37,130, and the Chevrolet Volt, at $36,803. Oregon showed the lowest price for 

both vehicles at $32,334 for the Nissan Leaf and $31,428 for the Chevrolet Volt. 

The final cost to the consumer for both vehicles in each state was calculated with the addition of the 

Federal income tax credit and the value of state incentives, as described above. Figure 3 shows the cost 

of a 2016 Nissan Leaf SV before and after incentives in the twenty states with the lowest price after 

incentives. 

 

17 Kelley Blue Book Co. 2016. https://www.kbb.com/

18 Reed, Philip. March 15, 2016. What New Car Fees Should You Pay? Edmunds. https://www.edmunds.com/carbuying/what-fees-should-you-pay.html#chart.

19 National Conference of State Legislatures. January 31, 2017. Registration and title fees by state. 

http://www.ncsl.org/research/transportation/registration-and-title-fees-by-state.aspx.
10

Figure 3. Cost of 2016 Nissan Leaf SV before and after incentives (ZEVR states are indicated by boxes 

around the state name)

For the Nissan Leaf, the state with the lowest cost after incentives was Colorado. This state had the 

second-highest cost before incentives (after Arizona), however, the large direct ZEV incentive available 

in that state reduced the final cost significantly. The state with the next lowest cost after incentives was 

Delaware. This state offered a significant ZEV purchase incentive as well as no state sales tax, making 

this one of the lowest cost states before and after incentives. Notably, these two states are not ZEVR

states. Arizona had the highest cost before and after incentives due to relatively high sales tax and fees 

and relatively low-value incentives.

Figure 4 shows the cost of a MY2016 Chevrolet Volt before and after incentives in the twenty states with 

the lowest post-incentive price. The state with the lowest price after incentives was Colorado, and the 

state with the highest price was Arizona. Colorado remained the lowest-price state after incentives for 

both the Nissan Leaf and the Chevrolet Volt due to the large tax credit that applied to both ZEVs and 

PHEVs.
11

Figure 4. Cost of 2016 Chevrolet Volt before and after incentives (ZEVR states are indicated by boxes 

around the state name)

2.4 Incentive Impact on Sales

State-by-state valuations of ZEV incentives available as of December 2016 were compared to 2016 statelevel market share for ZEVs and PHEVs. Market share data represent the percentage of new vehicle sales 

in 2016 and are from the Alliance of Automobile Manufacturers.20 Figure 5 shows the twenty states with 

the largest ZEV incentive values along with their 2016 market share for ZEVs. Figure 6 shows the twenty 

states with the highest PHEV incentive values along with their 2016 market share for PHEV. Market 

shares are shown as circles.

 

20 Auto Alliance. 2017. ZEV sales dashboard. https://autoalliance.org/energy-environment/zev-sales-dashboard/
12

Figure 5. ZEV 2016 incentive value and market share

Figure 6 PHEV 2016 incentive value and market share

As seen in Figure 5 and Figure 6, the valuation of state-level ZEV incentives was not well correlated with 

market share of ZEVs and PHEVs in 2016. For example, the four states with the highest ZEV market 

shares, Washington, Oregon, Hawaii, and Georgia, had relatively low ZEV incentive values. Oregon had 

one of the lowest incentive values, offering only a modest EVSE rebate, yet had one of the higher ZEV 

and PHEV market shares. Oregon credits their high adoption rates primarily to their extensive and well-
13

planned public EVSE network.21 This is also the case in Washington, which had a much higher ZEV and 

PHEV market share than states that offered more valuable incentives. These states, along with 

California, highlight the regional nature of ZEV and PHEV adoption trends. The west coast has a 

comparably robust electric vehicle charging network with thousands of Level 2 charging stations and 

dozens of direct current (DC) fast chargers, particularly along the Interstate 5 corridor through 

Washington, Oregon, and California. Availability of charging stations appears to be a strong driver for 

ZEV and PHEV adoption in this region. Hawaii also had high ZEV and PHEV market share, while ranking 

relatively low for incentive value. Hawaii has some unique drivers for ZEV and PHEV adoption, such as 

inherently limited driving distances and the highest gasoline prices in the country, in addition to a 

relatively robust EVSE infrastructure. In some cases, the 2016 incentives may not reflect prior incentives 

that were discontinued before 2016. This is the case with ZEV sales in Georgia, which had a low 2016 

incentive value yet had one of the highest ZEV market shares. This is due primarily to a large ZEV rebate 

program that ended in July 2015. 

In contrast, states such as Texas and Colorado had low ZEV and PHEV market share relative to the value 

of their incentives. In Texas, this may be due to the structure of the rebate program which, as discussed 

above, had much stricter eligibility requirements than most other states. Colorado’s tax credit program 

only began in mid-2016, which may explain the low market share. This is also the case in Delaware, 

which began offering rebates for ZEVs in November 2016, and shows a low 2016 ZEV market share.

Comparing sales and incentives over time shows that incentives, particularly rebates and tax credits, do 

have a direct impact on sales, at least in some states. For example, Figure 7 below shows monthly sales 

of ZEVs and PHEVs in Georgia from January 2013 to October 2016. A steep decline in ZEV sales is seen in 

July 2015, when the ZEV rebate was discontinued. 

Figure 7 Monthly ZEV and PHEV sales in Georgia from January 2014 to October 2016

 

21 Connor, Patrick. November 26, 2014. Oregon Proves Key To Electric Car Adoption Isn’t Necessarily Purchase 

Incentives. Transport Evolved. https://transportevolved.com/2014/11/26/oregon-proves-key-electric-caradoption-isnt-necessarily-purchase-incentives/
14

In contrast, monthly sales data for Rhode Island (Figure 8) do not show as clear an effect in response to 

the beginning of a PHEV rebate program in February 2015. 

Figure 8 Monthly ZEV and PHEV sales in Rhode Island from January 2015 to October 2016

As seen below, the correlation between total incentive value and market share is low. The correlation 

coefficient for total incentive value and market share is 0.1 for ZEVs and 0.2 for PHEVs. Figure 9 shows 

scatter plots of incentive value and market share for ZEVs and PHEVs.

Figure 9 Total 2016 incentive value and market share in states that offer ZEV and PHEV incentives

The ICCT White Paper, from which the methodologies in this analysis are derived, found a strong 

positive correlation between total incentive value and sales for both ZEVs and PHEVs in 2013. However, 

the current study did not find a strong correlation between total incentive value and sales or market 

share in 2016. This may be due to the greater number of ZEV and PHEV models available in 2016 

compared with 2013, suggesting a greater variety of auto dealers that need to be informed of the 

incentives. A 2013 UC Davis study found that many dealers in California were not aware of the various 

incentives at the state level, and for those that were, the incentives introduced multiple levels of 
15

uncertainty and risk.22 A more recent 2016 study of the vehicle shopping experience found that dealers 

failed to discuss available state rebates about 33 percent of the time.23

Overall, this analysis suggests that, while state incentives appear to play a role in ZEV and PHEV 

adoption rates, measurement of the significance of an incentive on sales requires data granularity on at 

least a monthly basis, and may also need to account for lags in development of incentive awareness as 

well as other factors. 

3 Sales Projections in Zero Emission Vehicle Regulation (ZEVR) States

ZEV and PHEV sales are assumed to be largely driven by regulations in the 10 states that have adopted 

Title 13 of the California Code of Regulations (CCR), Sections 1962.1 and 1962.2, which are referred to as 

the Zero Emission Vehicle Regulations (ZEVR) in this report. In addition to California, the ZEVR states 

include nine states that are referred to as S177 states because as allowed under Section 177 of the 

Clean Air Act, they have chosen to adopt California regulations to help achieve federal air quality

requirements. The S177 states are: Connecticut, Massachusetts, Maryland, Maine, New Jersey, New 

York, Oregon, Rhode Island, and Vermont.

The ZEV and PHEV sales projections in this report are based on the ZEVR and associated historic trends 

in sales and credit balances earned under the ZEVR. While incentives directed at ZEV and PHEV buyers 

(as described in Section 2) may assist manufacturers in achieving ZEVR compliance, these incentives are 

not directly included in the sales projections in this report other than how they may have affected 

historic sales trends. Note that the defined, simplified trends applied in the sales modeling do not 

capture potential changes over the forecast period such as changes in state-level programs or 

manufacturer strategies. In addition to simplifications and potential changes in trends, many 

complexities of the ZEVR are represented with basic assumptions. Collectively, the presented ZEV and 

PHEV sales forecasts are best considered as reasoned projections that provide an appropriate range of 

ZEV and PHEV sales through 2025, but no single scenario is viewed as substantially more probable than 

the others.

A high-level introduction to the ZEVR follows, after which the rules for awarding credits per vehicle and 

assumptions of vehicle electric range, which are used to calculate credits per vehicle, are presented in 

Section 3.2. An overview of rules for determining credit requirements and a projection of the number of 

required credits by state through 2025 is in Section 3.3. Section 3.4 assesses available state ZEV credit 

reports, uses data from these reports to project credit balances through 2017, and evaluates the portion 

of state sales by manufacturer size class. In Section 3.5, publicly available sales data is used to assess ZEV 

and PHEV sales in the ZEVR states, project sales through 2017, and project the split of sales between ZEV 

and PHEV through 2025. The final section (Section 3.6) explains the methods applied for ZEV and PHEV 

sales projections beyond 2017, and then presents sales at the state level in each of the ZEVR states 

through 2025 under several compliance scenarios.

 

22 Cahill, E., Davies-Shawhyde, J., and Turrentine, T. October 2014. New Car Dealers and Retail Innovation in 

California’s Plug-In Electric Vehicle Market. UC Davis Institute of Transportation Studies. 

https://itspubs.ucdavis.edu/wp-content/themes/ucdavis/pubs/download_pdf.php?id=2353

23 Sierra Club. 2016. REV UP Electric Vehicles. Multi-State Study of the Electric Vehicle Shopping Experience. 

https://www.sierraclub.org/sites/www.sierraclub.org/files/uploadswysiwig/1371%20Rev%20Up%20EVs%20Report_09_web%20FINAL.pdf
16

3.1 Introduction to the ZEVR

The purpose of the ZEVR is to encourage the adoption of vehicles that do not produce tailpipe 

emissions. These regulations are directed at manufacturers of light-duty vehicles with annual California 

sales above a set threshold. Each year, qualified manufacturers must be able to show a required 

minimum number of credits. These credits are generated from the sale of vehicles that meet the 

applicable clean vehicle definitions, where the number of credits earned per sale varies with technology 

and capability. The current version of the ZEVR is largely defined by the 2012 amendments, to which 

further amendments have been added. The ZEVR has a complex rule structure designed to offer 

manufactures flexibility in the paths they may take to achieve compliance, allowing each manufacturer 

to develop their preferred mix of compliant technologies. 

The ZEVR methods for calculation of the minimum number of credits needed per year is based on set 

percentages and the total number of light-duty vehicles (LDVs) the manufacturer produced and 

delivered for sale in California. Throughout the ZEVR, “production” refers to “production delivered for 

sale”, which in this report is considered to be equivalent to sales. Flexibilities in the types and timing of 

credit-earning sales are provided in the ZEVR by allowing manufacturers to bank credit surpluses for 

later use, transfer (sell or buy) credits, and make up credit shortfalls within specified timeframes. 

Further flexibility is allowed in the technology mix of credit earning sales. As a result, there are many 

possible compliance approaches, each of which can result in different numbers of vehicle sales needed 

to achieve the minimum number of required credits.

Due in part to advancements in battery performance and cost, electric vehicle driving range capability 

has exceeded expectation, and the automobile industry has on average produced a larger number of 

vehicles that earn more credits per vehicle than was anticipated when the rules were adopted in 2012. 

This has allowed the production of a smaller number of vehicles to achieve the required number of 

credits, along with a larger number of banked credits that may be used in future years. As a result, a 

smaller number of ZEVs and near-ZEVs may be placed on the road than was projected in the summary of 

the 2012 regulations developed by the California Air Resources Board’s (ARB) prior to adoption of the

current ZEVR.

24

3.2 Credit Types and Value Estimation

The types of credits in the ZEVR are summarized below followed by review of the rules defining the 

number of credits awarded per vehicle, estimation of the average range of ZEVs and PHEVs, and 

descriptions of credit from travel and credit from sources other than ZEV and PHEV sales.

3.2.1 Types of Credit-Earning Vehicles

The quantity and type of sales needed for compliance with the ZEVR are determined by the types of 

credits that can be earned and the ZEVR methods for setting credit values. Most of the credits used to 

comply are from the sale of ZEVs and near-ZEVs. Table 2 lists and describes vehicle types in the ZEVR and 

common names for sub-types. ZEVs include two sub-types: battery electric vehicles (BEV) propelled by 

energy stored in a battery pack, and fuel cell electric vehicles (FCEV) with on-board fuel cells that 

convert chemical energy from hydrogen into electric energy for vehicle propulsion. The other 

technologies listed in Table 2 are collectively referred to as near-ZEVs in this report. The most common 

 

24 Air Resources Board, California Environmental Protection Agency. 2011. Advanced Clean Cars Summary. 

https://www.arb.ca.gov/msprog/clean_cars/acc%20summary-final.pdf
17

near-ZEVs are Partial ZEVs (PZEV), Advances Technology ZEVs (ATPZEV), Transitional ZEVs (TZEV), and 

Neighborhood electric vehicles (NEV).

Table 2 ZEV and near-ZEV vehicle types

VEHICLE TYPE AND SUB-TYPE 

ZEV (Zero-emission Electric Vehicle) 

FCEV - Fuel Cell Electric Vehicle, converts hydrogen to electricity for propulsion

BEV -- Battery Electric Vehicle, uses electricity stored in batteries for propulsion 

PZEV (Partial ZEV) 

Conventional vehicle (low emissions)

AT PZEV (Advanced Technology PZEV) 

Gaseous – propulsion from an internal combustion engine that typically consumes 

natural gas vehicle

HEV -- Hybrid Electric Vehicle, with propulsion from both battery-stored electricity and 

a combustion engine that typically consumes conventional gasoline 

BEVx -- a BEV with a range extending, combustion ignition engine. Referred to as Type 1.5 

and Type IIx in the ZEVR. 

TZEV (Transitional ZEV)

PHEV -- Plug-in hybrid electric vehicle, a HEV with a battery pack that is able to be 

charged through a plug in connection to an external electricity source (i.e., the power 

grid)

BEVx – a BEV with a range extending, “limp-home” combustion ignition engine

HICE -- Hydrogen internal combustion engine

NEV (Neighborhood Electric Vehicle -short range, low speed) 

BEVx are not further addressed in this report because their market share has been relatively small, and 

is expected to decline further over the forecast period. PHEVs are the primary type of TZEV, and are 

expected to represent most of the sales in this category throughout the forecast period. Thus, while the 

ZEVR refers to requirements for TZEV credits, the projected earnings of TZEV credits are modeled as the 

sale of exclusively PHEVs. Both sales and credits are projected for ZEVs and PHEVs through 2025, while

only credits are projected for PZEVs, ATPZEVs, and NEVs because PZEV and ATPZEV sales are not eligible 

for generating new credits as of 2018, and new NEV sales are expected to be small compared to historic 

balances.

Most ZEV credits earned to date are from the sale of BEVs. While BEV dominance of the ZEV category is 

expected to continue, FCEV share is anticipated to increase as the nascent hydrogen refueling 

infrastructure further develops. California leads the nation in numbers of FCEV on the road and 

hydrogen refueling stations, with 20 stations operating in mid-2016,

25 suggesting this is where most of 

the FCEV sales will occur through 2025. In the Eastern states, hydrogen refueling infrastructure is in 

earlier stages of development, with plans for a corridor of refueling stations from Boston to New York 

 

25 Air Resources Board, California Environmental Protection Agency. July 2016. 2016 Annual Evaluation of 

Hydrogen Fuel Cell Electric Vehicle Deployment and Hydrogen Fuel Station Network Development. 

https://www.arb.ca.gov/msprog/zevprog/ab8/ab8_report_2016.pdf
18

City26 that will encourage FCEV sales. But overall, FCEV sales are expected to remain a small portion of 

ZEV sales through 2025, and thus are not separately delineated in this report. 

3.2.2 Credit per Vehicle Rules

Prior to 2018, credits per ZEV are based on the vehicle subcategory as defined by vehicle range and fast 

recharging capability.

27 Credits per PHEV are also based on technological capabilities with an allowance 

for vehicle miles traveled determined through a prescribed method. 28 The methods for calculating

credits per vehicle change in 2018, with the maximum possible number of credits per vehicle falling 

from nine to four. This decline occurs along with a drop in credit requirements, followed by credit 

requirement increases in subsequent years as discussed in Section 3.3. In this report, vehicle sales and 

credit balances through 2017 are estimated from trends in historic sales and credit balances, while sales 

estimates from 2018 onward apply the applicable ZEVR credit per vehicle formulae to convert the target 

number of earned credits over the forecast period to vehicle sales.

From 2018 onward, credits per ZEV delivered for sale are calculated with a single formula that uses the 

Urban Dynamometer Driving Schedule (UDDS) All-Electric Range (AER) as follows:

29

 

Credit per ZEV = 0.01 x AER + 0.50

where credits per ZEV are capped at 4.0. This formula does not apply to NEVs, which are assigned 0.15 

credits in 2018 and later years. From 2018 onward, PHEV credits are calculated using the following 

formula with a cap of 1.10 (equivalent to 80 miles):30

Credit per TZEV = (0.01) x EAER + 0.30

where EAER is the UDDS Equivalent All-Electric Range. An additional 0.2 credits are earned by PHEVs 

that achieve an AER of at least 10 miles under the US06 drive cycle. To achieve an AER, PHEVs cannot 

blend the use of the electric and internal combustion propulsion systems under conditions of high 

power demand, rather, the battery pack is fully depleted before the internal combustion engine can 

engage.31 Non-blended systems are also referred to as “US06 capable”, in reference to the more 

aggressive (higher speed and more rapid accelerations) US06 drive cycle under which their AER is 

determined. US06 PHEVs are viewed as next-generation vehicles and as such, are expected to have 

higher average EAER than prior generations.

3.2.3 Average ZEV and PHEV Range 

Trends in ZEV and PHEV ranges are used to project average ranges over the forecast period, which are 

used to calculate credits per vehicle from 2018 onward (Section 3.2.2). Under the ZEVR, the ranges of 

ZEV and TZEV models are tested using the UDDS drive cycle and specified California test procedures.

32

Ranges per vehicle model determined with the California procedures are not generally available, but 

 

26 Edelstein, Stephen. April 8, 2016. Sites of four Northeast hydrogen fueling stations announced by Air Liquide. 

Green Car Reports. http://www.greencarreports.com/news/1103307_sites-of-four-northeast-hydrogen-fuelingstations-announced-by-air-liquide

27 ZEV credits per vehicle are described in CCR 1962.1(d)(5)(B) and (C)

28 TZEV credits per vehicle are described in CCR 1962.1(c)(2), CCR 1962.1(c) (3) and CCR 1962.1(c) (4)(B)

29 The credit per ZEV formula for 2018 onward is in CCR 1962.2 (d)(1)(A)

30 The credit per TZEV formula for 2018 onward is in CCR 1962.2 (c)(3)(A)

31 Air Resources Board, California Environmental Protection Agency, 2017. California’s Advanced Clean Cars 

Midterm Review, Summary Report for the Technical Analysis of the Light Duty Vehicle Standards (ARB Midterm 

Review). https://www.arb.ca.gov/msprog/acc/mtr/acc_mtr_finalreport_full.pdf , Page H-1.

32 ZEV test procedures listed in CCR 1962.2 (d)(1)(A), TZEV test procedures listed in CCR 1962.2 (c)(3)(A)
19

ranges determined with the EPA test procedures33 are shown on the EPA fuel economy label.

34

 To 

estimate the UDDS all-electric range from the EPA label range, a factor of 1.428 is applied.35

The average ranges of annual PHEV and ZEV sales from 2012 through 2016 were estimated from EPA 

label ranges

36 weighted by national annual sales by model as reported by Inside EVs.37

 Each marker in

Figure 10 represents the average calendar-year label range for a ZEV model that was sold in the 

corresponding year. The calendar year range for each model is estimated as the average reported range

for the current and subsequent model years and for available model options that affect this range (e.g., 

battery pack size, motor size and number, etc.). For a given model, minimal variation was found among 

the calendar year offerings except for Tesla models. For example, in calendar year 2016, the label range 

for a Tesla Model S varied from 210 to 315 miles among the available model years and battery pack and 

motor options. 

A lack of publicly available sales data by model option limits the precision of average range estimates for 

ZEV sales, nevertheless, as seen in Figure 10, average range per model exhibits a bimodal distribution.

Tesla model averages and the 2017 Chevrolet Bolt have ranges in excess of 220 miles, and all other 

models having label ranges between 60 and 110 miles. Sub-group averages and market share are shown 

in Table 3. Other manufactures are expected to launch new ZEV models with ranges greater than 200 

miles over the next few years. Table 3 also shows the sales-weighted average label range per ZEV range 

group along with the percentage of ZEV sales represented by each of these groups.

Figure 10. ZEV range: Tesla, Chevrolet, and 

others. (Each point represents a ZEV-model 

average range for the calendar year

Table 3. Weighted average label range, share of 

ZEV range groups for calendar years 2012 

through 2016

Sales-Weighted 

Average Range*

<200 mi >200mi

% of ZEV Sales 

<200 mi >200mi

2012 73 229 81% 19%

2013 77 229 63% 37%

2014 84 255 75% 25%

2015 83 255 64% 36%

2016 96 256 44% 56%

* For each year, average label range for each 

model is weighted by sales.

 

33Test procedures for EPA label ranges are described at https://www.epa.gov/fuel-economy/fuel-economy-testingand-data

34 The EPA/DOT-required window label for new vehicles that display fuel economy and annual fuel cost. For BEV 

and PHEV, this label also shows all-electric driving range.

35 ARB Midterm Review, 2017. Page A-11. 

36 EPA fuel economy labels were viewed at http://www.fueleconomy.gov/feg/

37 Inside EVs. 2017. Monthly plug-in scorecard. http://insideevs.com/monthly-plug-in-sales-scorecard/
20

PHEV average range was estimated using a method similar to that used for ZEVs where the calendar 

year average range of each PHEV model was weighted by sales as reported by Inside EVs. PHEV ranges 

varied from 11 to 53 miles as seen in Figure 11. EPA fuel economy labels do not indicate US06 capability, 

but the Chevy Volt and the Toyota Prius Prime are reported to be US06 PHEVs.38 As next-generation 

technology, US06 PHEV models tend to have higher range than most basic PHEVs, as seen in Figure 11

and Table 4. Over the next several years, other manufacturers are expected to introduce US06 PHEVs 

that will also have greater label all-electric range. Range improvements are projected separately for 

basic and US06 PHEVs to allow better estimation of average credits per PHEV due to the additional 

credit that can be earned by US06 PHEVs. 

Figure 11. Range of PHEV models (Each 

point represents a ZEV-model average 

range for the calendar year

Table 4 Weighted average label range, share of 

PHEV range groups for calendar years 2012 through 

2016 

Sales-Weighted 

Average Range*

Basic US 06

% of ZEV Sales 

Basic US 06

2012 12 35 39% 61%

2013 16 38 53% 47%

2014 16 38 65% 35%

2015 20 32 64% 36%

2016 19 51 66% 34%

* For each year, average label range for each model is 

weighted by sales.

The ranges and percentages of ZEV and PHEV sales shown in Table 3 and Table 4 are used as historical 

references for the projection of average ZEV and PHEV label ranges through 2025 (Figure 12). Range 

improvements in the < 200 mile range BEV group are projected to follow historic trends. For the >200 

mile range BEV group, the 2016 average range is applied throughout the forecast period because after 

adjustment of EPA label range to UDDS range, the ZEV credit cap is reached with an EPA label range of 

245 miles. Thus, while there may be range increases in this subgroup, these improvements will not 

increase credits per vehicle. 

From 2018 to 2025, the average range of basic PHEVs is increased by 1 mile each year, and US06 PHEV 

average range is increased by 0.5 miles each year. A lower rate of increase in average range is projected 

for US06 PHEVs because as additional manufacturers begin to offer US06 PHEVs, their initial models of 

this type are expected to have relatively low ranges for this subcategory. Figure 13 shows the projected 

share of BEVs that will have >200 miles range, and the share of PHEVs that will be US06 PHEVs. The 

share of BEVs with >200 miles range is capped at 80% to allow for a potential submarket to counter high 

range BEVs with large battery packs that do not provide sufficient benefit relative to the cost.

 

38 ARB Midterm Review, 2017. Page H-1. 
21

Figure 12. Average electric range for PHEVs and 

BEVs

Figure 13. Percent of ZEVs that are BEV >200 

mile range and percent of PHEVs that are US06 

PHEVs

3.2.4 Credit Travel

Under what is commonly referred to as the “travel provision”, the ZEVR allows credits earned for BEVs 

and FCEVs in any ZEVR state be given credit in other ZEVR states at a value proportional to the LDV sales 

in each S177 state relative to California sales through model year 2017. 39 Manufacturers must apply for 

credit travel prior to 2018. Beginning in 2018, only FCEV credits are allowed to travel. Credit travel 

increases the total number of credits generated by a single sale. For example, in 2016, one fully traveled 

credit, meaning a credit that travels to the greatest extent possible enabling it to be counted 

proportionately in all ZEVR states, is estimated to earn a collective total of 2.47 credits. The value of a 

fully traveled credit changes each year based on the relative proportion of production in each S177 state 

compared to California. The LDV sales forecast used in this report suggests that a single fully traveled 

2016 credit may provide a total of 2.47 credits, and between 2018 and 2025, a single fully traveled credit 

may provide between 2.39 and 2.45 credits. But, for credits earned in states other than California, travel 

reduces credit value in the state in which it was earned, so it may not be desirable to travel all credits. 

3.2.5 Other Types of Credits

The ZEVR allows limited use of other types of credits. One of these is the use of greenhouse gas (GHG)

over compliance credits. With advance notice of plans to use GHG over-compliance credits, these credits 

may fulfill up to 50% of the minimum ZEV requirements in 2018 and 2019, falling to 40%, 30%, and 0% in 

2020 through 2022, respectively.40 In the ARB Midterm Review scenarios,41 GHG-ZEV over compliance 

credits are estimated to be used by 10% to 20% of large manufacturers.42 In this report, it is assumed 

that 15% of large manufacturers will use the maximum allowable GHG over-compliance credits. GHG 

over-compliance credits are subtracted from total estimated credit requirements in the appropriate 

 

39 The travel provision prior to 2018 is in CCR 1962.1(d)(5)(E). The provision for 2018 and later years is in CCR 

1962.2(d)(5)(E).

40 Rules for the use of GHG over-compliance credits are in CCR 1962.2(g)(6)(C)

41 ARB Midterm Review.2017. Page A-19. 

42 Manufacturers were to inform ARB of their intent to use GHG credits no later than December 31, 2016, allowing 

reasonable estimation of the number of GHG-ZEV credits that may be used.
22

years since these credits essentially reduce the number of ZEVs and PHEVs that need to be sold. Other 

alternative means of earning ZEV credits are assumed to be a very small portion of credit earnings and 

are not accounted for in the sales estimations presented in this report. These alternative credits include: 

medium-duty vehicle credits from ZEVs and TZEVs; transportation system credits; advanced technology 

demonstration program credits; and hydrogen internal combustion engine credits.

3.3 Credit Requirements 

Credit-type categories correspond to the vehicle-type categories shown above in Table 2. The number of 

total credits required and the minimum number of ZEV credits required is determined based on vehicle 

model year and manufacturer size. Small manufacturers have no credit requirements, but they can sell 

any earned credits to intermediate or large manufacturers. The ZEVR rules distinguish three size classes 

of manufacturers based on their previous California sales of combined light and medium-duty vehicles: 

Large Vehicle Manufacturers (LVM), Intermediate Vehicle Manufacturers (IVM), and Small Vehicle 

Manufacturers (SVM). The definitions for these size classes change in 2018. Current and post-2017 

definitions and rule distinctions for the size classes are shown in Table 5. 

Table 5. ZEVR manufacturer size class definitions and credit requirement distinctions

 

Manufacturer 

Size Class 

2012 to 2017 2018 to 2020 2021 Onward 

LDV Sales 

Credit 

Distinction 

LDV Sales, Global 

Revenue 

Credit 

Distinction LDV Sales 

Credit 

Distinction 

Large Volume 

Manufacturer 

(LVM)

> 60,000 Minimum 

%ZEV credits

> 20,000 sales

>$40 billion

Minimum 

%ZEV credits

> 20,000 Minimum 

%ZEV credits

Intermediate 

Volume 

Manufacturer 

(IVM)

4,501 to 

60,000

Can meet full 

requirement 

with PZEV 

credits

4,501 to 20,000 Can meet full 

requirement 

with TZEV 

credits

No change

Small Volume 

Manufacturer 

(SVM)

≤ 4,500 Not subject 

to ZEV rules No change No change

In the Section 177 states that have adopted the ZEVR, manufacturers have notified regulators of their 

intent to follow either the basic path for credit requirements, or an optional path. The optional S177 

Path has higher requirements in 2016 and 2017, and lower requirements in 2018 through 2020. Both of 

these paths are discussed below, followed by a state-by-state estimation of credit requirements through 

2025. 

3.3.1 Basic Path 

Credit requirements for large and intermediate-sized manufacturers are calculated in each ZEVR state as 

percentages of LDV production in the state measured as a three-year floating average of the second, 

third, and fourth prior years. Figure 14 shows total credit requirements as a percentage of production. 

Sub-portions are shown for the minimum total requirement that must be met with ZEV credits

(applicable only to large manufacturers) and the maximum amount of the total requirement that can be 

met by near-ZEV credit categories. Each type of credit has different capabilities for use to fulfill other 

credit-type categories. ZEV credits may be used in all categories; TZEV may be used in all but ZEV 

categories; AT PZEV may be used in PZEV categories; while PZEV credits can only be used in the PZEV 
23

category. The actual types of credits used by manufacturers are considered private strategic 

information, thus how closely credit use follows the distribution of credit types shown in Figure 14 is not 

publicly known. The drop in the total credit requirement seen in 2018 along with the merging of PZEV 

and ATPZEV categories in 2018 and subsequent years corresponds with the 2018 rule changes.

Figure 14. Large vehicle manufacturer credit requirements: minimum ZEV, maximum of near-ZEV 

credit use (Discounted credits are combined PZEV and ATPZEV credits)

3.3.2 Optional S177 Path

Manufacturers were able to choose an “Optional S177 State Compliance Path” under which more 

credits are required in S177 states in 2016 and 2017 and less credits are required in 2018 through 2020.

43

 The 2016 and 2017 credit increases cannot use traveled credits. As part of the optional path, 

manufacturers are allowed to transfer credits among states in East and West regional pools (separated 

by the Mississippi River) from 2016 through 2021. The intent of pooling is to facilitate vehicle sales in the 

geographical areas with highest ZEV demand – from a manufacturer standpoint, it allows focus on rapid 

increases in sales in more limited areas. A 30% premium is applied to credits that are transferred 

between the regional pools, while there are no penalties for transfers within the same regional pool. 

Oregon is the only state in the West pool, since California is excluded from the Optional S177 Path. 

Manufacturers were required to inform ARB of their choice to pursue the Optional S177 State 

Compliance Path by September 1, 2016. The ZEV Compliance Calculator44 released in 2017 indicates that 

90% of large vehicle manufacturers have chosen the Optional S177 path while no intermediate vehicle 

manufacturers have done so. 

3.3.3 Estimated Requirements through 2025

State-by-state credit requirements are calculated as the product of the percentage requirement in the 

ZEVR and the volume of production delivered for sale in each state. As previously stated, in this report, 

production delivered for sale is considered to be equivalent to sales. Production is calculated as a threeyear rolling average of the second, third, and fourth prior-year LDV sales.

45

 This estimation method 

 

43 Requirements under the optional S177 path are described in CCR 1962.2(d)(5)(E)2

44 Air Resources Board, California Environmental Protection Agency. 2017. ZEV Compliance Calculator Tool (Excel 

file). https://www.arb.ca.gov/msprog/zevprog/zevcalculator/zevcalculator_2017.xlsx

45 Calculation of production delivered for sale is described in CCR 1962.1(b)(1)(B)
24

assumes LDV production will not decrease.46 In this report, required credits are estimated from LDV 

sales as forecast in the AEO2017 Reference case47 and adjusted based on production data provided in 

ZEV credit reports. Appendix A provides more detail on the LDV sales forecast used to estimate LDV 

production. Estimates of credit requirements were adjusted as appropriate by share of production 

represented by manufacturers that have opted for the Optional S177 Path (Section 3.3.2), share of 

manufacturers that have indicated they will be using GHG over-compliance credits (Section 3.2.5), and

by manufacturer size class (Section 3.4.4).

Figure 15 and Table 6 show estimated total required credits for the ZEVR states. In 2018, approximately 

46% of the total required credits are in California, decreasing to 41% in 2025. With minimal change

between 2018 and 2025, the two Eastern states with the largest credit requirements, New York and 

New Jersey, represent 36% and 25%, respectively, of total Eastern credit requirements. Massachusetts,

Maryland, and Connecticut have medium-sized requirements, with each state representing between 8% 

and 13% of total Eastern requirements. Maine, Rhode Island, and Vermont have small-sized 

requirements, with each state representing between 2% to 3% of total Eastern credit requirements. 

Differences between each state’s share of total required credits and their share of minimum required 

ZEV credits are less than 1%.

Figure 15. Total required credits, 2018 and 2025

Table 6. Estimated total required credits in 2018

(thousands)

Category State Total Credits 

WEST 

 California 80.3

 Oregon 5.0

EAST 

Large New York 31.9

New Jersey 21.5

Medium

Massachusetts 11.7

Maryland 10.8

Connecticut 6.7

Small

Maine 2.1

Rhode Island 1.7

Vermont 1.4

Total credits required across all ZEVR states increase between five- and six-fold from 2018 to 2025. In 

contrast, the minimum ZEV credit requirement increases more than 12-fold over the same period in 

most states. 

 

46 Manufactures can choose to calculate their credit requirement based on the current model year production as 

described in CCR 1962.2(b)(1)(D), which would presumably be chosen in the event of a decline in LDV production.

47 U.S. Energy Information Administration (EIA), 2017. Light-Duty Vehicle Sales by Technology Type. Annual Energy 

Outlook 2017 (AEO2017). https://www.eia.gov/outlooks/aeo/
25

3.4 Credit Reports, Balances, and Size Classes

The ZEVR calls for each state to develop annual ZEV credit reports. These credit reports provide 

historical credit balances by manufacturer. This report uses the historic credit balances to assess trends 

in credit balances by credit type and state through 2017. Credit balances in 2017 are an essential risk 

mitigation measure since credit requirements increase at a greater rate starting in 2018 than in the past. 

Credit reports also provide a list of large and intermediate manufacturers for the reported year,48 in 

addition to LDV vehicle production by manufacturer. Production data from the credit reports is used to 

estimate credit requirements (which also depend on manufacturer size class), and to predict changes in 

manufacturer size classes through 2025.

3.4.1 Available Credit Reports

California ZEV Credit Reports are available online. The most recent report, for model year 2015, was 

released in October 2016.49 Credit reports for other states are not consistently available online as a 

result of differing agreements between each state and vehicle manufacturers, in addition to delays 

collating the relevant data in some states. However, many of the unpublished state reports can be 

obtained by request from the appropriate state agency. Table 7 shows the years for which credit reports 

were obtained for each state, and indicates if the report included both production and credit balance 

data, or just credit balance data. 

Table 7 Zero Emission Vehicle Credit Reports Used for this Project.

● = credit balances and production data

○ = only credit balance data

 

2012 2013 2014 2015 

California ● ● ● ● 

New York ● ● 

New Jersey ● ● ● 

Massachusetts ● ● ● 

Maryland ○ ○ ● ● 

Oregon ● 

 

Connecticut ○ ● 

Maine ○ ● ● 

Rhode Island ● ● 

Vermont ● 

3.4.2 Credit Balance Differences Among the States

Historically, manufacturers have carried credit balances as a result of selling more ZEVs and near-ZEVs in 

a year than what was needed for compliance. These banked credits reduce manufacturer risk of falling 

out of compliance due to below-target sales in future years. A build-up of banked credits prior to 2018 

 

48 For any given year, the list of large and intermediate manufacturers is the same in all states because size class is 

determined based on manufacturer sales in California.

49 Air Resources Board, Californian Environmental Protection Agency, October17, 2016. 2015 Zero Emission Vehicle 

Credits. https://www.arb.ca.gov/msprog/zevprog/zevcredits/2015zevcredits.htm
26

may be particularly desirable given the more rapid increase in credit requirements from 2018 through 

2025. The ratio of total credit balances to estimated credit requirements based on the available ZEV 

credit reports is shown in Figure 16. In 2015, credit balances, which include historic credit surpluses 

from prior years, were between 3.5 and 7.5 times greater than the model year credit requirement. 

Figure 16. Ratio of total credit balances to credit requirements, 2012 to 2015

The proportions of the different types of banked ZEV credits vary among the ZEVR states. This reflects

differences in the types of surplus earned credits in each state, and suggests there may also be 

differences in the proportions of credit types used to meet the requirements in each state. The following 

summary of trends in credit types that comprise total balances is based on review of the states for 

which there is more than one year of credit balance data, as shown in Figure 17.

 The share of ZEV credits in total balances is growing, and NEV and ATPZEV credits are declining.

 The share of PZEV and TZEV credits is constant or slightly declining.

 Relatively high portions of ATPZEV and PZEV credits in New Jersey and California suggest these 

states will be most affected by the discounting of these credits in 2018.

 NEV credit share is greatest in New York and Massachusetts, at 26% and 24% of the 2015 balance, 

respectively. In the other states, NEV share is 10% or less. Most NEV credits were earned prior to 

2012 from sales of low-speed, low range vehicles for use on campuses and other localized areas.

 ZEV credit share in 2015 is greatest in Rhode Island (51%), followed by Maryland (48%), Vermont

(46%), and Oregon (40% in 2014). ZEV credits compose 36% to 38% of credit balances in all other 

states in 2015. The high portion of banked ZEV credits in Rhode Island and Vermont likely 

represent travel credits considering the low number of ZEV sales in these states and the inability 

to otherwise exchange credits among states until 2016.

 TZEV share of banked credits is greatest in Vermont (29%), followed by Rhode Island (27%), 

Oregon (23%), and Maine (22%). In all other states, TZEV credits compose 13% or less of total 

credit balances in 2015.
27

Figure 17. Share of credit types in state credit balances

3.4.3 Estimation of Credit Balances through 2017

Credit balances beyond the last credit reports (MY 2015) were estimated from trends in historic credit 

balances.50 Figure 18 shows reported credit balances (when available) through 2015, and projected 

balances for 2016 and 2017. Note that in 2015, credit requirements increased from 0.79% to 3% of 

production, and there are no further changes in requirements until 2018. As such, the use of a linear 

trend from 2013 through 2015 to project 2016 and 2017 balances may yield conservative estimates.

 

50 In both the ARB Midterm Review and the NDRC report at https://www.nrdc.org/sites/default/files/mediauploads/nrdc_commissioned_zev_report_july_2016_0.pdf), credit balances are estimated from trends in sales in 

conjunction with the number of credits per vehicle and assumptions on the amount of ZEV credit use for 

requirements that can be met with near-ZEV credits. But detailed data on average credits per vehicle by state and 

year is not publicly available, nor are details available on the credit types used to meet requirement portions that 

can be met with near-ZEV credits, hence the more direct method of using balance trends was preferred for this 

report despite incomplete balance data for some states.
28

Figure 18. ZEV credit balances

While historic credit balances include both surplus credits earned in the state and credits traveled to the 

state, the ARB Midterm Review notes that credit travel has lagged behind credit earnings.

51 The delay in 

traveling credits suggests that some manufactures may wait until 2017 to fully travel credits earned in 

prior years, creating a potential surge in 2017 balances. This surge, however, may be reduced if some 

credits do not fully travel.

Since travel does not reduce credit value in California, it is always advantageous to fully travel credits 

earned in California to the S177 states. But a manufacturer anticipating greater difficulty meeting future 

requirements in a particular S177 state may choose to not travel credits from that state. There may be a 

particular reluctance to travel credits from states with much lower credit requirements than other states 

because traveled credits retain very little of their original value in these states. In the states identified in 

Table 6, above, as having a “small” number of required credits, credits that travel out will retain only 2 

to 3% of their earned value in these states. While a larger view of the benefit to industry-wide credits 

encourages travel, traveling out credits results in a higher sales need in some states, which may be 

viewed as increasing risk beyond the benefit of traveling all credits.

The use of travel credits to eliminate risk of ZEV credit non-compliance in small states through 2025 is 

suggested from a comparison of ZEV sales and credit balances (Table 8). Credits earned per ZEV sold 

prior to 2018 range from 2 to 7 credits, and ARB estimates that in 2015, the average ZEV sold in 

California earned 3.29 credits.

52 The 2015 ZEV credit balances in the small states (Maine, Rhode Island, 

and Vermont) are more than 10 times greater than the credits that would be earned if all the ZEVs sold 

in these states between 2012 and 2015 were 7-credit vehicles (i.e., Tesla models). If credit balances 

continue their rate of growth through 2017, ZEV balances will be sufficient to meet the minimum ZEV 

requirements through 2024 in Maine and Rhode Island, and through 2025 in Vermont. This suggests the 

possibility of delaying the need to have ZEV sales in these smallest states, allowing a concentration of 

sales efforts in other Eastern states through the first half of the 2020’s.

53

 It also suggests that in the 

 

51 ARB Midterm Report. 2017. Page A-8.

52 Ibid., page A-7.

53 If no ZEV balances were available in ME, VT, and RI, between 1,500 and 2,500 ZEV sales would be needed in each 

of these states in 2025 – the current regulations have the same percentage requirements for subsequent years.
29

redistribution of East Pool credits that may occur from 2016 through 2021, there may be minimal 

transfer of ZEV credits from these small states.

Table 8. 2015 ZEV credit balance, cumulative 2012 to 2015 ZEV sales, and ratios of total 2015 credit 

balance to cumulative ZEV sales and to total 2015 credit requirements

 

 2015 

Balance 

2012 to 

2015 Sales 

Balance/ 

Sales* 

Balance/ Total 

Requirement 

WEST 

 California 345,054 88,962 3.9 1.6

 Oregon** 31,823 4,476 7.1 1.9

EAST 

Large New York 129,510 3,710 34.9 1.2

New Jersey 94,188 2,877 32.7 1.2

Medium Massachusetts 60,983 2,400 25.4 1.4

Maryland 57,721 2,075 27.8 1.5

Connecticut 31,088 1,310 23.7 1.2

Small Maine 18,520 173 107.1 2.3

Rhode Island 18,961 157 120.8 3.0

 Vermont 17,994 229 78.6 3.4

* A balance/sales value near the estimated average credits per ZEV of 3.3 is thought to suggest minimal 

travel-in credits, although it may also occur when the value of travel-in credits is nearly the same as the 

value of travel-out credits.

** Oregon 2015 credit balance is estimated from reported 2014 balance and balance growth relative to 

Maryland, which had similar relative ZEV sales growth between 2014 and 2015.

Overall, there is uncertainty in both the extent to which pre-2017 credits will travel and in the portion of 

travel that may have already occurred. As such, the estimation of 2016 and 2017 credit balances based 

on trends in historic credit balances (as in this report) provides a relatively conservative estimate of 

balances that does not incorporate a potential 2017 surge in travel credits.

3.4.4 Manufacturer Size Classes and Market Share

The size class of major manufacturers is assigned based on their production as listed in California ZEV 

credit reports. The market share of each manufacturer in each state is estimated based on the credit 

report data for the state, and manufacturers of the same size class are then lumped together to 

determine market share by size class in each state. Many of the current IVMs are expected to transition 

to the LVM class under the 2018 rules, resulting in a greater portion of required credits that will need to 

be fulfilled by ZEV sales. The rules for transferring between IVM and LVM classes require that a 

manufacturer have five consecutive three-year averages of qualifying sales (including both light and 

medium duty vehicles) that exceed 20,000, and a global revenue in excess of $40 billion in 2018, 2019, 

and 2020. Manufacturers that meet the sales qualification but not the global revenue qualification will 

need to meet LVM rules the year after exceeding the sales threshold for five consecutive years that 

begin after 2020 (i.e., the soonest they would need to meet LVM requirements is in 2026). Table 9

shows the size class of manufacturers in 2015, and anticipated sizes classes in 2018 and 2026, no 

changes are anticipated in the between years.
30

Table 9. Current and projected size class by manufacturer

L = Large; I = Intermediate; S = Small a

Manufacturer 2015 2018 2026

Chrysler Group L L L

Ford L L L

GM L L L

Honda L L L

Nissan L L L

Toyota L L L

Volkswagen I L L

Hyundai I L L

BMW I L L

KIA I L L

Mercedes Benz I L L

Subaru I I L

Mazda I I L

Jaguar Land Rover I I I

Mitsubishi bS L L

Volvo S I I

Tesla S I L

a. This list only includes small manufactures expected to change their size class during the forecast period.

b. Assumes Nissan’s purchase of Mitsubishi is completed by 2018.

Table 10 shows the proportion of state LDV sales that were sold by LVMs in 2015 based on vehicles 

delivered for sale in the 2015 ZEV Credit Reports (2014 for Oregon). 2015 production as shown by 

manufacturer in the 2015 credit reports was used to estimate the portion of production that will be by 

LVMs in 2018, when several of the current IVMs transition to LVM status. For the sales forecast 

scenarios in this report, LVM market share in 2015 is held constant in 2016 and 2017, and LVM market 

share estimated for 2018 is held constant for the remainder of the forecast period. 

 Table 10. LVM market share by state, 2015 and 2018

 2015 * 2018 

California 72% 94%

Connecticut 66% 86%

Massachusetts 79% 90%

Maryland 74% 92%

Maine 76% 86%

New Jersey 70% 92%

New York 75% 93%

Oregon 70% 88%

Rhode Island 69% 90%

Vermont 75% 85%

* Based on 2015 credit reports from each state except Oregon, 

which is based on their 2014 credit report.
31

3.5 Sales through 2017

ZEV and PHEV sales through 2017 are used as a basis for forecasting sales through 2025 in Section 3.6. 

The relative share of ZEV and PHEV sales is also important for assessing trends in the market share of 

these two technologies, which as discussed in Section 3.2.2, have significantly different credit earning 

potential per vehicle. As such, market share trends will be used in the sales forecasting described in 

Section 3.6.

3.5.1 Sales by State

ZEV and PHEV sales data were obtained from the Auto Alliance ZEV Sales Dashboard,

54

 which reports 

sales by state through 2016. Sales in 2017 are estimated as a linear trend of sales from 2013 through 

2016. The linear trend did not include 2012 sales due to the relatively few ZEV and PHEV models 

available in 2012. As seen in Figure 19 and Figure 20, year-on-year ZEV sales were reduced in 2014 in 

Connecticut, Maryland, New Jersey, and New York. Year-on-year declines in PHEV sales have been more 

prominent, with reductions in 2014 in Connecticut, Massachusetts, Maine, New Jersey, New York, 

Rhode Island, and Vermont. The following year saw PHEV sales reductions in California, Maryland, 

Oregon, and Rhode Island. Year-on-year sales declines suggest the importance of retaining generous 

credit balances to assure compliance, particularly with the annual increase in credit requirements from 

2018 through 2025.

Figure 19. ZEV sales by state, 2012 to 2017 Figure 20. PHEV sales by state, 2012 to 2017

3.5.2 ZEV to PHEV Sales Ratio

For sales forecasting, the ratio of ZEV sales to combined ZEV and PHEV sales (ZP sales) is used to divide 

estimated sales among these technologies. Figure 21 shows the historic ratio of ZEV to ZP sales through 

2016, with an average of the four prior years used to estimate the ratio for 2017, and subsequent years 

 

54

 Auto Alliance, 2017. ZEV Sales Dashboard. https://autoalliance.org/energy-environment/zev-sales-dashboard/
32

shown with annual increases in the ZEV share of the ZP market of 2% of the prior year ratio. This rate of 

increase is one of the base assumptions for the sales projections in this report

Figure 21. ZEV share of the ZP market: 2012 to 2016 historic data, 2017 average of prior years, 2018 

onward estimated with increases of 2% per year

As particularly seen for Maine and Vermont in the lower graph of Figure 21, an assumption that ZEV 

share of ZP sales is increasing may be viewed as tenuous. Nonetheless, the more rapid increase in 

minimum ZEV credit requirements versus credit requirements that can be met with TZEV credits 

suggests that ZEV share of ZP sales will increase. To meet ZEVR requirements with the minimum number 

of ZEV credits using average credits per vehicle based on the average ranges shown in Figure 12, above, 

ZEV share of ZP sales would need to be 0.13 in 2018 versus 0.37 in 2025, assuming with no banked 

credits or credit transfers.

Other considerations also suggest that the ZEV share of the ZP market should increase over the longer 

term. A manufacturer’s choice of the types of vehicles to produce likely considers the expected per 

vehicle cost and possible profitability versus credit earning potential. From an automotive business 

standpoint, sales volume and the number of years since a major re-design are typically important factors 

in the profitability of a particular model. Both of these factors challenge the profitability of ZEVs and 

PHEVs at this stage of their development. The ZEVR endeavors to push technology development, and 

presumably long-term profitability, by enticing compliance through a penalty of $5,000 per required 

credit that is not achieved.

55 This suggests a ZEV worth 4 credits in 2018 (i.e., an EPA label range of at 

least 245 miles) could be sold at a loss of up to $20,000 before the loss would exceed the penalty of 

noncompliance. In contrast, no more than $5,500 could be lost on a TZEV as a result of the 1.10 credit 

cap on these vehicles in 2018. The lower margin for loss in conjunction with the greater required sales 

volume may discourage TZEV production, particularly if a manufacturer is able to produce and sell a 4-

credit ZEV within the acceptable loss range. Over the longer term, prices of ZEV components (i.e., 

battery packs, motor drives) are expected to decline as production efficiencies improve. 

 

55 Penalties are in addressed in CCR 1962.2(g)(8)
33

3.6 Sales Estimation for 2018 through 2025

As an emerging technology, ZEVs and PHEVs are expected to have technology improvement and cost 

reductions throughout the forecast period. While technology may experience major jumps beyond 

gradual improvements and stimulate sales, unforeseen failures and issues may dampen them. Although 

these types of unpredictable events are not included in this analysis, risk mitigation is accounted for, as 

discussed in the next subsection. This is followed by a description of the sales estimation method for 

2018 through 2025, and sales projections under several scenarios.

3.6.1 Accounting for Risk Mitigation

An underlying assumption of the Excel-based sales model used in this analysis is that the ZEVR is a key 

driver of ZEV and PHEV sales in ZEVR states. Further, the inconsistent, and sometimes negative year-onyear growth in ZEV and PHEV sales (seen above in Figure 19 and Figure 20) presents a risk for 

manufacturers, particularly given the annual increases in credit requirements from 2018 through 2025. 

The low number of ZEV and PHEV models offered by each manufacture also presents non-compliance 

risk. A technological issue or otherwise poor market acceptance of just one ZEV or PHEV model that 

results in significant sales reductions can have a greater effect on compliance achievement when few 

models are offered.

In addition to reduction of ZEVR non-compliance risks, annual sales in excess of requirements may be 

part of strategies by some manufacturers to increase their long-term auto market share through 

establishing a higher market share of ZEVs and PHEVs. Government incentives for ZEVs are offered in 

countries ranging from China, South Korea, and India, to European Union members, indicating global 

interest in electric-powered drivetrains. Potential pro-ZEV market strategies beyond ZEVR compliance 

are not included in this analysis. 

Recognizing the historical and likely future holdings of significant credit balances to assure ZEVR

compliance, the sales model developed for this analysis forecasts ZEV and PHEV sales from 2018 through 

2025 based on the ZEVR with an input variable for the ratio of the 2025 year-end credit balance to the

2026 credit requirements (CBCR). CBCR is a means to mitigate the risks of lower than expected sales. 

While a manufacturer can opt to set their credit requirements based on their current year LDV sales 

rather than the rolling average of prior years, this option does not provide relief when the sales drop is 

only in ZEV or PHEV sales. 

The magnitude of credit balances is expected to decline over the 2018 to 2025 period due to both 

maturing of the market (reduced risk) and increased requirements. In the ARB Midterm Review,

56 it is 

noted that in addressing “compliance margins to ensure compliance given uncertainties . . .

manufacturers . . . typically expressed targets of one to two years depending on their tolerance for risk.” 

3.6.2 Base Assumptions

Unless noted otherwise, the ZEV and PHEV sales scenarios in this report use the following assumptions:

1. CBCR (ratio of 2025 credit balances to 2026 credit requirements) – CBCR is set at 1.5, which is 

the midpoint of the compliance margins manufacturers are reported to be targeting.

57

 

56 ARB Midterm Review. 2017. Page A-9. 

57 Ibid.
34

2. Minimum allowable year-on-year (YoY) growth for combined ZEV and PHEV (ZP) sales –

minimum allowable YoY sales growth is set at 4%. This minimum is applied when the 

combination of credit balances and historic sales relative to requirements are substantial 

enough to allow achievement of the target CBCR with less than the set minimum growth. In the 

scenarios in this study, the minimum YoY is only applied to California. A 4% YoY sales increase is 

roughly half of the growth rate that would be needed in California to maintain a linear trend of 

ZP sales from 2013 to 2016, onward to 2025, and results in a CBCR of about 2.

3. LDV sales forecast – the LDV sales forecast is used to calculate required credits. It is based on 

the AEO2017 Reference case as adjusted by production data provided in ZEV credit reports, as 

further described in Appendix A.

4. Average credits per vehicle type – average credit per vehicle type for each year from 2018 

through 2025 are estimated from the ZEVR credit formulae for 2018 onward, using estimated 

annual improvements in average range as shown in Section 3.2.3, Figure 12.

5. LVM market share – LVM market share throughout the forecast period is held constant at the 

shares projected for 2018, as shown in Section 3.4.4, Table 10.

6. East pool credit redistribution -- East pool credit balances and sales in 2018 through 2021 are 

redistributed among all East pool states according to the proportion of East pool credit 

requirements represented by each state.

7. Ratio of ZEV to ZP sales (ZEV/ZP) – the ZEV share of the ZP market increases annually at a rate 

of 2% of the prior year ZEV to ZP ratio (i.e., the ratio is multiplied by 1.02 each year).

3.6.3 Sales Estimation Method for 2018 to 2025

Combined ZEV and PHEV (ZP) sales projections from 2018 through 2025 are estimated as: 

Need-to-Earn Credits = Equ. 1

∑ Required Credits

2025

2018

+ CBCR (Required Credits2026)− Historic Credit Balance

Where,

Historic Credit Balance = Equ. 2

ZEV Balance2017 + TZEV Balance2017 + Discounted PZEV Balance2017 +

Discounted ATPZEV Balance2017 + Allowable NEV Use

CBCR refers to the ratio of 2025 credit balances to 2026 credit requirements, and,

Allowable NEV Use = ∑ 25% Required TZEV Credits ×

NEV Balance2017

Production Portion2015

2025

2018 Equ. 3

In all states, discounted PZEV and ATPZEV balances are projected to be fully used by the end of 2019 or 

2020. This is in consideration of their maximum allowable use per year of 25% of the TZEV requirements 

adjusted by the portion of production that has PZEV or ATPZEV balances in 2015. As such, total historic 

discounted PZEV and ATPZEV balances are used in the above equation for Historic Credit Balances. In 

contrast, for NEV balances, Massachusetts and New York are projected to have 2017 NEV balances that 

exceed allowable NEV use during the 2018 through 2025 period and as such, are represented as 

“Allowable NEV Credit Use” in the calculation of Historic Credit Balances.

Although no new credits need to be earned while sufficient historic credits are available, production 

risks are generally thought to be reduced with consistent, small increases in production versus large 

increases such as would be needed if there were no sales while historic credits were used. As such, 
35

annual sales are modeled based on a calculated constant YoY growth in ZP sales for each state under 

each scenario. For each state under each scenario, YoY growth in ZP sales is determined based on total 

needed credits after redistribution under East Pool scenarios. 

Pooling under the Optional S177 State Path is not applied to the West because California is excluded 

from the Optional Path, leaving only Oregon in the West Pool. Credit exchanges between the East and 

West pool are allowed between 2016 and 2021 with a 30% premium. In recent years, ZEV sales in 

Oregon have been around 35% of ZEV sales in the East Pool, but ZEV minimum requirements in Oregon 

are around 5% of East Pool requirements. This suggests a relatively strong initial growth in sales in 

Oregon, but a relatively small potential market compared to the East pool. Overall, while the transfer of 

credits from Oregon to the East pool may be part of the credit strategy for some manufactures, the size 

of the Oregon market is not thought to be large enough to substantially influence sales in the East Pool 

throughout the forecast period, and is not included in the modeled sales. 

For each state, sales from 2018 through 2025 are set to provide earned credits equal to need-to-earn 

credits,

where a = ZP Sales2017, and x = YoY sales growth,

ZP Sales2018 = a + ax Equ.4

ZP Sales2019 = a + 2ax + ax

2

Equ. 5

.

.

.

ZP Sales2025 = a + 8ax + 28ax

2 + 56ax3 + 70ax4 + 56ax5 + 28ax6 + 8ax7 + ax8

 Equ. 6

It follows that,

ZEV Sales = ZP Sales × ZEV Market Share Equ. 7

Where ZEV Market Share is a scenario variable based on historic share as shown in Figure 21. Further,

PHEV Sales = ZP Sales − ZEV Sales Equ. 8

A minimum YoY is set to prevent showing negative growth in California. The Excel goal seek function, 

which iteratively tests input values for a given formula to find a set result, is used to estimate YoY with 

the goal of Need-to-Earn Credits (Equ. 1.) set to result in Earned Credits where:

Earned Credits = Equ. 9

∑ ZEV Sales × CPVZEV

2025

2018

+ ∑ PHEV Sales × CPVPHEV

2025

2018

The goal seek path from YoY sales growth to Earned Credits is shown in Figure 22, alongside the goal of 

Need to Earn Credits.
36

Figure 22. Use of goal seek to estimate percent year-on-year sales growth

3.6.4 Sales Forecast with Base Assumptions

ZEV and PHEV sales under a scenario using all the base assumptions listed in Sections 3.6.2 are shown in 

Figure 23 and Figure 24, respectively. Table 11 shows cumulative sales, and average ZEV/ZP and %YoY ZP 

sales growth from 2018 through 2025 for each state. In California, as a result of relatively high historic 

sales, associated credit balances, and high ZEV/ZP sales, ZP sales growth over the forecast period is at 

the minimum allowed, 4% YoY growth. 

Figure 23. ZEV sales, base case assumptions Figure 24. PHEV sales, base case assumptions
37

Table 11. Cumulative sales and average ZEV/ZP sales and %YoY ZP sales growth from 2018 to 2025

 

Cumulative Sales (thousand) Average 

 

ZEV PHEV ZP ZEV/ZP %YoY 

CA 477 347 824 0.58 4%

CT 45 52 97 0.45 48%

MA 76 82 158 0.47 44%

MD 74 84 158 0.45 51%

ME 10 31 41 0.23 67%

NJ 141 168 309 0.44 52%

NY 176 328 504 0.34 54%

OR 36 17 53 0.67 13%

RI 10 18 28 0.34 58%

VT 6 21 27 0.22 45%

Under the base assumptions, ZEV and PHEV sales in New York grow much faster than in California in 

terms of %YoY growth, and annual New York PHEV sales exceed California PHEV sales in 2023. By 2025, 

annual New York ZEV sales are nearly as high as California ZEV sales, and annual New York PHEV sales 

are more than double California PHEV sales. Several factors cause the loss of California dominance of 

the ZP market. The minimum sales growth applied to California allows continued increases in end-ofyear ZEV balances (after meeting credit requirements) through the early 2020’s. Although total credits 

estimated to be earned from 2025 sales represent only about 50% of the targeted CBCR, the shortfall is 

made up with prior-earned credits. At the end of 2025, the California credit balance under this scenario 

is estimated to be about twice the total credit requirements in 2026 (i.e., a CBCR of 2.0 versus the target 

of 1.5). The low growth in California PHEV sales in Figure 24 is a result of both the 4% growth rate for ZP 

sales and the growing market share for ZEVs, which in this scenario is 54% of the ZP market in 2018, 

increasing annually by 2% of the prior-year share to 62% in 2025, with corresponding decreases in PHEV 

market share. 

The total credit requirement in New York is about half the total requirement in California. In the baseassumptions scenario, New York uses the last of its historic (pre-2018) credits in 2022, and in 

subsequent years earns just enough credits to meet the target CBCR. The high PHEV sales shown for 

New York are due in part to the relatively low historic ZEV share of the ZP market. In this scenario, ZEV 

sales comprise 32% of the New York ZP market in 2018, increasing annually by 2% of prior-year share to 

36% by 2025, with corresponding decreases in PHEV market share. The result is an average %YoY ZP 

sales growth of 54% in New York, versus 4% in California. It should be recognized that higher ZEV/ZP 

ratios would reduce sales growth, and the actual rate of increase in the ZEV/ZP ratio may vary among 

the states. The base assumption of ZEV/ZP sales increases that are 2% of the prior year ratio yields lower 

annual increases in states such as New York, where the current ZEV share of ZP sales is relatively low. 

Under the base assumptions, three states have 2018 ZEV shares of ZP sales that are equal to or lower 

than New York’s, these states are Rhode Island, Maine, and Vermont, with 2018 ZEV shares of the ZP 

sales of 32%, 22%, and 21%, respectively. As suggested in Section 3.4.3, the relatively high ZEV credits in 

these three smallest states may be part of a strategy to build up ZEV balances in these states with travel 

credits, and perhaps also with transfer credits under the Optional S177 path, to levels that allow ZEV 

compliance through 2025 with reduced sales. The high sales growth needed in these states under the 

base assumptions scenario suggests the appeal of strategies to reduce the need for sales in the smaller 
38

Eastern states, which would allow more focus on ZEV sales in the medium and large Eastern states. Sales 

focus may then shift to the three small states in the mid 2020’s, after the ZEV market is better 

established in the other Eastern states.

3.6.5 Effect of East Pool Redistribution on Sales Forecast

Two sets of scenarios were examined to assess the possible effects on sales from East pool credit 

redistribution, as allowed from 2016 through 2021 under the optional S177 path. Redistribution was 

applied to both historic credits (earned prior to 2018) and credits earned from new sales during the 

applicable years. Descriptions of the first set of scenarios follow, with each scenario given a short name 

for reference in presentation of the results:

 “No Redistribution” – historic credits and new sales credits are not redistributed in the East 

pool, and historic credits stay in the state where they were in 2017.

 “Requirements”– same as the East pool redistribution described above as a base assumption 

(i.e., East pool credits are redistributed among all East pool states according to the proportion of 

East pool credit requirements represented by each state). 

 “Catch-Up” – credit redistribution is based on both proportionate credit requirements and the 

historic relative rate of sales whereby if a state’s sales portion is 2% higher than their 

requirements portion in the East pool, the Catch-Up portion is 2% lower than the requirements 

portion. A minimum allowed redistribution portion of 0.5% is set to prevent a reallocation that 

results in a negative balance.

Table 12 shows cumulative sales from 2018 through 2025 in each state under these three scenarios, and 

Figure 26 displays the differences in cumulative sales with East pool credit redistributions compared to 

the scenario with no credit redistribution (the zero-line in Figure 26). East states with relatively high 

credit balances at the end of 2017 relative to other states in the East pool, particularly the small states 

(i.e., Vermont, Rhode Island, and Maine), have reduced balances as a result of credit redistribution

under the examined scenarios. As a result, the small states need higher cumulative sales from 2018

through 2025. Credit redistribution has an opposite effect on states with relatively low credit balances at 

the end of 2017 relative to other East pool states, particularly New York and New Jersey. These credit 

redistribution scenarios result in higher credit balances and lower cumulative sales in the large states.

Table 12 Cumulative sales, 2018 to 2025 (thousands) under East pool redistribution scenarios of “No 

redistribution”, “Requirements”, and “Catch-Up”

West East Large East Medium East Small

Scenario CA OR NY NJ CT MA MD ME RI VT

ZEV

No Redistribution 476.8 35.8 181.6 149.2 45.2 77.5 75.4 5.9 5.1 1.7

Requirements 476.8 35.8 175.7 141.1 45.4 75.8 74.1 9.8 9.9 6.4

Catch-up 476.8 35.8 166.6 135.3 51.1 83.8 79.6 8.7 9.0 6.2

PHEV

No Redistribution 346.9 16.9 338.4 177.8 52.2 83.4 85.4 18.7 9.4 5.8

Requirements 346.9 16.9 327.6 168.3 52.4 81.6 84.0 31.2 18.1 21.3

Catch-up 346.9 16.9 310.8 161.5 58.9 90.0 90.0 27.8 16.5 20.9
39

Figure 25. Change in cumulative sales with East pool redistribution under “Requirements” and “Catchup” scenarios compared to the “No redistribution” scenario (zero-line)

The second set of scenarios to assess the possible effects on sales from East pool credit redistribution 

are described below, with each scenario given a short name for reference in presentation of the results:

 “All East” – same as the East pool redistribution described above as a base assumption and for 

the “Requirements” scenario (i.e., East pool credits are redistributed among all East pool states 

according to the proportion of East pool credit requirements represented by each state).

 “Large-Medium” – credit redistribution among only the large and medium east pool states, with 

redistribution to each state based their proportionate credit requirements.

 “Surge + Large-Medium” – East state credit redistribution as in the “Large-Medium” scenario 

with higher ZEV credit balances at the beginning of 2018, such as would occur if 15% of the 2016 

ZEV balances travel to all states prior to the end of 2025.58 

Table 13 shows cumulative sales from 2018 through 2025 in each state under these three scenarios. 

Figure 26 displays the differences in cumulative sales with East pool credit redistributions under the 

Large-Medium and Surge + Large-Medium scenarios compared to credit redistribution under the All East 

scenario (the zero-line in Figure 26).

 

58 In the ARB Midterm Review, it is suggested that as of 2016, a significant number of ZEV credits have not traveled.
40

Table 13 Cumulative ZP sales, 2018 to 2025 (thousands), under East pool redistribution scenarios of 

“All East”, “Large-Medium”, and “Surge + Large-Medium”

West East Large East Medium East Small

Scenario CA OR NY NJ CT MA MD ME RI VT

ZEV

All-East 476.8 35.8 175.7 141.1 45.4 75.8 74.1 9.8 9.9 6.4

Large-Med 476.8 35.8 181.7 145.7 46.8 78.4 76.5 5.9 5.1 1.7

Surge + Large-Med 476.8 32.9 167.4 134.6 43.6 72.4 70.9 5.1 4.3 1.2

PHEV

All-East 346.9 16.9 327.6 168.3 52.4 81.6 84.0 31.2 18.1 21.3

Large-Med 346.9 16.9 338.5 173.7 54.0 84.3 86.6 18.8 9.4 5.8

Surge + Large-Med 346.9 15.6 312.2 160.7 50.4 78.0 80.3 16.3 8.0 4.1

Figure 26. Change in cumulative sales with East pool credit redistribution under “Large-Medium” and 

“Surge + Large-Medium” scenarios compared to the “All East” scenario (zero-line)

As was seen in the first set of scenarios, redistribution of small-state credit balances (“All States” 

scenario, Figure 27) results in substantially higher sales in the small states compared to the sales needed 

in these states when their credits are not redistributed (“Large-Medium” scenario, Figure 27). Under the 

same scenarios, sales increases in medium and large states due to an absence of credits from small 

states, but these increases are small compared to sales needed in the large and medium states (“All 

States” and “Large-Medium” scenarios, Figure 28 and Figure 29). A surge in 2017 credit balances could 

reduce sales in medium and small states by more than the benefit of redistributed credits from small 

states (“Surge + Large-Medium” and “All States” scenarios, Figure 26, Figure 28, and Figure 29), although 

it should be recognized that surge magnitude is uncertain.
41

Figure 27. Small Eastern states: ZEV and PHEV sales under “All States” and “Large-Medium” credit 

redistribution scenarios; “Large-Medium” redistribution scenario with 2% and 6% annual ZEV/ZP 

growth; and “Large-Medium” redistribution scenario with and without a 2017 credit surge
42

Figure 28. Medium Eastern states: ZEV and PHEV sales under “All States” and “Large-Medium” credit 

redistribution scenarios; “Large-Medium” redistribution scenario with 2% and 6% annual ZEV/ZP 

growth; and “Large-Medium” redistribution scenario with and without a 2017 credit surge
43

Figure 29. Large Eastern states: ZEV and PHEV sales under “All States” and “Large-Medium” credit 

redistribution scenarios; “Large-Medium” redistribution scenario with 2% and 6% annual ZEV/ZP 

growth; and “Large-Medium” redistribution scenario with and without a 2017 credit surge

3.6.6 Effect of ZEV Share of the ZP Market on Sales Forecast

The effect of more rapid growth in ZEV share of the ZP market was examined by changing the rate of 

annual growth in the ZEV share of ZP sales (ZEV/ZP). Under the base assumptions, ZEV/ZP increases 

annually by 2% of the prior year ratio. Annual growth in ZEV/ZP of 2% (black dotted line) and 6% (solid 

yellow line) of prior year ratios can be compared for the Eastern states under the same pool 

redistribution assumptions in Figure 27, Figure 28, and Figure 29, above. With a higher rate of growth in 

ZEV/ZP, PHEV sales decrease by more than ZEV sales increase as a result of the higher average credits 

per ZEV than per PHEV. Sales changes due to ZEV/ZP growth rate changes are generally greater in the 

medium and large Eastern states than in the small Eastern states. This is due to the combination of 

lower historic ZEV/ZP in smaller states and the scenario description of ZEV/ZP growth as a percentage of 

the prior year ratio. The scenario definition assumes proportionate growth in ZEV sales share among the 

states rather a growth rate that is independent of the historic ZEV/ZP. 

Figure 30 shows annual ZEV and PHEV sales in California and Oregon under scenarios with 6% and 2% 

annual increases in ZEV/ZP, with the later also shown with and without a 2017 surge in credit balances 

(the same as “Surge + Large-Medium” in Section 3.6.5). A 2017 surge in credit balances does not change 

ZEV and PHEV sales projections for California because ZP sales growth in California uses the minimum of 

4% YoY ZP sales growth. When this minimum is disregarded, the average %YoY growth in California ZP 

sales (with all other base assumptions retained) is 1%. This growth rate decreases to negative 1% under 

the credit surge scenario, indicating that ZEVR compliance in California could be achieved with slight 

decreases in year-on-year sales. 
44

Similar to what is seen in the Eastern states, the credit surge scenario reduces both ZEV and PHEV sales 

in Oregon (Figure 30), while an increase in the rate of ZEV/ZP growth increases ZEV sales and decreases 

PHEV sales. 

Figure 30. Western states: ZEV and PHEV sales under scenarios of 2% annual ZEV/ZP growth with and 

without a 2017 credit surge; and a scenario of 6% annual ZEV/ZP growth without a surge

3.6.7 Collective Scenarios

None of the scenarios presented in this analysis is viewed as substantially more probable than the 

others. Collectively, the presented ZEV and PHEV sales forecasts provide a reasoned range of possible 

ZEV and PHEV sales in each ZEVR state through 2025. 

In the Eastern states, compliance with ZEVR requirements is expected to drive ZEV and PHEV sales 

throughout the forecast period, forcing substantial average year-on-year sales increases. Figure 31, 

shows average percent annual ZEV and PHEV sales growth from 2018 through 2025, with the error bars 

representing the range of annual growth projections under the tested scenarios. Most of the Eastern 

states will need annual sales growth that averages between 40% and 60% over the forecast period. 

Actual annual year-on-year sales increases are likely to vary substantially in all states. For example, from 

2012 to 2016, year-on-year combined ZEV and PHEV sales growth in California varied from 5%to 100%, 

with an average of 44%. Some of this variation has been attributed to the cycle launching and 

discontinuing models,

59 which is particularly notable with fewer available models. Large percentage 

 

59 ARB Midterm Review.2017. Page B-9.
45

increases in annual production and sales may be more challenging when ZEV and PHEV sales are higher 

and proportionate increases represent a larger magnitude.

In Oregon, sales increases needed to meet credit requirements are modest compared to the Eastern 

states as a result of relatively high historic ZEV sales in Oregon. If rapid sales growth is easier to achieve 

in Oregon, manufacturers that have opted for the Optional S177 Path under the ZEVR may choose to 

transfer some credits from Oregon to Eastern states during the allowed period (i.e., 2016 through 2021), 

despite the 30% premium applied to these transfers (a scenario that is not modeled in this study).

In California, the ZEVR requirements may serve to limit potential reductions in ZEV and PHEV sales as 

new production is directed to other states. Assuming a California sales growth rate of 4% per year for 

combined ZEV and PHEVs, collective annual average ZEV and PHEV sales growth among all the ZEVR 

states is estimated to be between 20% and 30% throughout the 8-year forecast period. 

Figure 31. Average and range of year-on-year ZEV and PHEV sales growth from 2018 through 2025 

under the tested scenarios

The range of cumulative sales from 2018 through 2025 for the tested scenarios is indicated by the error 

bars shown in Figure 32. For large and medium Eastern states, PHEV sales are highest under the scenario 

with no growth in ZEV share of ZP sales, while both the highest ZEV sales and the lowest PHEV sales are 

under the scenario with the highest growth in ZEV share of ZP sales. This suggests that cumulative ZP 

sales in the medium and large Eastern states may be particularly sensitive to the split between ZEV and 

PHEV sales. 

For the small East states, highest ZEV and PHEV sales are under the scenario with credit redistribution 

(from 2016 through 2021) among all East states proportionate to their credit requirements. Both ZEV 

and PHEV sales are lower under the scenarios that exclude small states from credit redistribution within 

the Eastern pool. The size of these sales reductions relative to the requirements in Vermont and Rhode 

Island, in particular, suggests the possibility of using travel and transfer credits to delay the need for ZEV 

and PHEV sales in these states until the mid-2020’s. The ZEVR credit requirements continue beyond 

2025, so ZEV and PHEV sales increases in these states will still ultimately be needed.
46

Figure 32. Cumulative ZEV and PHEV sales from 2018 to 2025 under the tested scenarios

In closing, with respect to future modeling of FCEV sales, which are not distinguished within the ZEV 

sales in this study, the BEV market is expected to expand to largely meet the ZEV requirements for 2025 

onward with a relatively small portion of ZEV sales that will be FCEV. This suggests the possibility that 

unlike BEVs and PHEVs, FCEV sales growth may be better projected by new technology adoption factors 

other than the ZEVR.
47

Appendix – Light-Duty Vehicle Sales Forecast

Estimation of the ZEV credit requirement is based on a rolling average of three prior years of vehicle 

production delivered for sale. Thus, required credits (both total and minimum pure ZEV) are estimated 

from LDV sales as forecast in the AEO2017 Reference case.

60 These sales are provided for nine census 

regions that collectively represent the entire country. Regional sales are adjusted to state sales by 

applying the ratio of state vehicle registrations to regional vehicle registrations as reported for 2014 by 

the Federal Highway Administration (FHWA).61 A constant ratio of state-to-regional 2014 sales is used 

throughout the modeling period. Sales are further adjusted based on historic sales as indicated by 

production reported in the state ZEV Credit Reports. As seen in Figure 33, reported state production is 

within 10% of sales as estimated from AEO2017 regional sales and FHWA state registrations for six 

states of the ten ZEVR states. A 10% deviation is exceeded for the remaining four states, with the 

greatest deviation for Oregon, where reported production in 2014 was 28% higher than estimated.

Figure 33. AEO2017-based LDV sales as percent of state credit report production delivered for sale

As seen in Figure 34, historical annual LDV sales in the ZEVR states are more volatile than forecast sales, 

not because the future is certain to be smoother, but rather because the greatest causes of variation are 

often not predictable. ZEV and PHEV sales forecasts in this report are built on the underlying assumption 

of gradual year-on-year changes in LDV sales shown in Figure 34, in which the automotive 

manufacturing industry does not experience conditions or events that cause substantial changes in total 

LDV sales. 

 

60 U.S. Energy Information Administration, January 5, 2017. Annual Energy Outlook 2017 with projections to 2050. 

https://www.eia.gov/outlooks/aeo/

61 Federal Highway Administration, US Department of Transportation. December 2015. State Motor-Vehicle 

Registrations – 2014. http://www.fhwa.dot.gov/policyinformation/statistics/2014/mv1.cfm
48

Figure 34. Light-duty vehicle sales for ZEVR states, 2009 to 2026

Figure 34 also shows the relative amounts of total LDV sales among the ZEVR states. California 

represents roughly 40% of the total LDV sales in ZEVR states, followed by New York at 20%, New Jersey 

at 15%, and the remaining seven states collectively represent about 25% of LDV sales in ZEVR states.