A national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

National Renewable Energy Laboratory 

Innovation for Our Energy Future 

Historical Perspective of 

Clean Cities and Alternative 

Fuels Data Center Trends 

J.K. O’Connor 

Technical Report 

NREL/TP-540-41069 

September 2007 

NREL is operated by Midwest Research Institute ● Battelle Contract No. DE-AC36-99-GO10337 
National Renewable Energy Laboratory

1617 Cole Boulevard, Golden, Colorado 80401-3393 

303-275-3000 • www.nrel.gov 

Operated for the U.S. Department of Energy 

Office of Energy Efficiency and Renewable Energy 

by Midwest Research Institute • Battelle 

Contract No. DE-AC36-99-GO10337

Technical Report 

NREL/TP-540-41069 

September 2007 

Historical Perspective of 

Clean Cities and Alternative 

Fuels Data Center Trends 

J.K. O’Connor 

Prepared under Task Nos. FC07.0023, BB07.9021 
NOTICE

This report was prepared as an account of work sponsored by an agency of the United States government. 

Neither the United States government nor any agency thereof, nor any of their employees, makes any 

warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or 

usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not 

infringe privately owned rights. Reference herein to any specific commercial product, process, or service by 

trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, 

recommendation, or favoring by the United States government or any agency thereof. The views and 

opinions of authors expressed herein do not necessarily state or reflect those of the United States 

government or any agency thereof. 

Available electronically at http://www.osti.gov/bridge

Available for a processing fee to U.S. Department of Energy 

and its contractors, in paper, from: 

U.S. Department of Energy 

Office of Scientific and Technical Information 

P.O. Box 62 

Oak Ridge, TN 37831-0062 

phone: 865.576.8401 

fax: 865.576.5728 

email: mailto:reports@adonis.osti.gov

Available for sale to the public, in paper, from: 

U.S. Department of Commerce 

National Technical Information Service 

5285 Port Royal Road 

Springfield, VA 22161 

phone: 800.553.6847 

fax: 703.605.6900 

email: orders@ntis.fedworld.gov

online ordering: http://www.ntis.gov/ordering.htm

Printed on paper containing at least 50% wastepaper, including 20% postconsumer waste
 i

Contents 

Executive Summary........................................................................................................................iii 

Acronyms.......................................................................................................................................... v 

Background ...................................................................................................................................... 1 

Report Objective .......................................................................................................................... 2 

Acknowledgments........................................................................................................................ 2 

Light-Duty Original Equipment Manufacturer Vehicle Offerings............................................. 3 

Original Equipment Manufacturer Models Offerings 1991 to 2006 ........................................... 3 

Original Equipment Manufacturer Offerings by Fuel Type, 1991 to 2006 ................................. 4 

Recent Trends in Alternative Fuel Vehicle/Hybrid Electric Vehicle Offerings .......................... 8 

Fueling Station Analysis................................................................................................................ 12 

Introduction................................................................................................................................ 12 

Fueling Station Database Validation ......................................................................................... 12 

Fueling Station Database Analysis ............................................................................................ 13 

Public/Private Refueling Site Analysis...................................................................................... 14 

Station Owner Type ................................................................................................................... 15 

State and Federal Laws and Incentives ....................................................................................... 17 

The Clean Cities Program............................................................................................................. 22 

Background................................................................................................................................ 22 

General Clean Cities Information .............................................................................................. 22 

The National Alternative Fuels and Clean Cities Hotlines ........................................................ 24 

Background................................................................................................................................ 24 

Hotline Request Processing and Evaluation – the Details......................................................... 26 

Requests by Fuel Type............................................................................................................... 27 

Sources of Requests Received by the Hotline/Technical Response Service ............................. 29 

Hotline Feedback ....................................................................................................................... 30 

Request Categories..................................................................................................................... 32 

Fleet Managers........................................................................................................................... 35 

Final Remarks ................................................................................................................................ 36 

Appendices...................................................................................................................................... 37 

Appendix I. Raw Data Used To Generate Some Original Equipment Manufacturer Figures by 

Models Offered and Fuel Type ............................................................................................ 37 

Appendix II. Original Equipment Manufacturer Charts Showing Models Offered by Fuel Type 

over Time............................................................................................................................. 38 

Appendix III. Laws and Incentives—Supplemental Information.............................................. 41 

Appendix IV. Map of Clean Cities Coalitions........................................................................... 42 

Appendix V. Supplementary Hotline State and Country Usage Information............................ 43 

Appendix VI. Organization Type of Hotline Users................................................................... 45 
Figures 

Figure 1 Light-Duty OEM AFV/HEV Models Offered 1991-2006 . . . . . . . . . . . . . . . . . . . . 3

Figure 2 AFV/HEV Models Offered by OEMs 1991-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Figure 3A AFV/HEV Models by OEM/Fuel Type 1991-2006 (# of models) . . . . . . . . . . . . . 5

Figure 3B AFV/HEV Models by OEM/Fuel Type 1991-2006 (percentage) . . . . . . . . . . . . . . 5

Figure 4 AFV/HEV Models by Fuel Type/OEM 1991-2006 (# of models) . . . . . . . . . . . . . 6

Figure 5 AFV/HEV Models by Fuel Type/OEM 1991-2006 (percentage) . . . . . . . . . . . . . . 7

Figure 6 OEM AFV/HEV Models Available 2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figure 7 AFV/HEV LDV Model Offerings by Fuel Type 1998-2006 . . . . . . . . . . . . . . . . . . 8

Figure 8 AFV vs. Hybrid OEM Models 2000-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Figure 9 OEM AFV/HEV Models By Vehicle Type 1991-2006 . . . . . . . . . . . . . . . . . . . . . . 9

Figure 10 U.S. Hybrid Vehicle Sales 2000-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 11 U.S. Hybrid Sales 2004-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Figure 12 AFV Refueling Sites by Fuel Type 1998-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Figure 13 Refueling Sites By Fuel Type 2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Figure 14 E85, Biodiesel, & CNG Station Trends 1998-2006 . . . . . . . . . . . . . . . . . . . . . . . . . 15

Figure 15 Public/Private Proportions of Refueling Stations by Fuel Type in 2006 . . . . . . . . . 15

Figure 16 2006 Alternative Fuel Stations by Ownership Type . . . . . . . . . . . . . . . . . . . . . . . . 16

Figure 17 Federal and State Laws and Incentives by Incentive Type (2006) . . . . . . . . . . . . . 18

Figure 18 Laws & Incentives by Regulation Type (2006) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 19 Laws & Incentives By Fuel/Technology (2006) . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Figure 20 L&I By Fuel/Technology by Year . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure 21 Laws & Incentives by User Type (2006) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 22 Population Covered by Clean Cities Coalitions (2000 Census Data) . . . . . . . . . . . 23

Figure 23 States with >2 Clean Cities Coalitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Figure 24 Hotline/TRS Requests (FY92-06) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 25 Hotline Docs Distributed FY96-FY06 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 26 Hotline Referral Types 1995-2006 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Figure 27 Hotline Fuel Type Requests (FY95-05) (annual) . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Figure 28 Hotline Fuel Type Requests (FY95-05) (combined) . . . . . . . . . . . . . . . . . . . . . . . . 28

Figure 29 Hotline Fuel Type Requests FY05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 30 TRS Requests by Fuel Type FY06 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 31 Sources of Requests Received at the Hotline By Fiscal Year (FY97-FY06) . . . . . . 30

Figure 32 Hotline Operator/Operations Feedback 1996-2005 . . . . . . . . . . . . . . . . . . . . . . . . . 31

Figure 33 Were Hotline Expectations Met? (User Feedback FY96-05) . . . . . . . . . . . . . . . . . 31

Figure 34 Hotline Comparison to Other Hotlines (1996-2005) . . . . . . . . . . . . . . . . . . . . . . . . 32

Figure 35 Grades on Documents Distributed to Hotline Users (1996-2005) . . . . . . . . . . . . . . 32

Figure 36 Fleet Managers AFDC Utilization by FY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Tables 

Table 1 Top 20 Most Popular Hotline Request Categories (FY 1991-2006) . . . . . . . . . . . 33

Table 2 Top 20 Most Popular Hotline Request Categories (FY 2005-2006) . . . . . . . . . . . 

. 

34

ii
Executive Summary 

This document draws on the wealth of information housed in the U.S. Department of Energy’s 

(DOE) Alternative Fuels Data Center (AFDC) at the National Renewable Energy Laboratory. 

Trends and analyses are examined from data as far back as 1991. The findings of those trends 

and salient features are summarized. The AFDC is available at www.eere.energy.gov/afdc/. 

Original Equipment Manufacturer Vehicle Offerings 

• Ford, General Motors, and DaimlerChrysler (the U.S. “Big Three” original equipment 

manufacturers [OEMs]) have offered about 80% of all alternative fuel vehicle (AFV) and 

hybrid electric vehicle (HEV) models since 1991. 

• The Big Three concentrated on compressed natural gas (CNG) and flexible-fuel vehicles 

(FFVs) during the 1990s, and offered some liquefied petroleum gas (LPG) vehicles. 

• Only Honda and General Motors offered CNG models in 2006. 

• The Big Three AFV models of 2006 focused on FFVs; an estimated 6 million FFVs were 

on the roads in 2006. 

• Toyota and Honda entered the HEV market in 2000 with the Honda Insight and the 

Toyota Prius. HEV sales were about 254,000 in 2006, according to Energy Futures. 

• Ford made the first Big Three entry into the HEV market with the Escape model in 2005. 

• Neither Toyota nor Honda has ever offered an FFV model. 

• In 2006 no OEM made an LPG model, and only Global Electric Motorcars made an 

electric vehicle (EV), its neighborhood electric vehicle. 

Alternative Fuel Vehicle Refueling Stations 

• CNG sites peaked in 1999 and have been in steady decline since. 

• Ethanol (E85—a blend of 85% ethanol and 15% gasoline) stations demonstrated dramatic 

growth between 2004 and 2006. 

• The growth of biodiesel fueling opportunities mirrored that of E85 between 2004 and 

2006. 

• E85 stations surpassed the CNG station total in 2006 and biodiesel stations are expected 

to exceed the number in 2007. 

• LPG stations have always reflected the greatest number of fueling opportunities, but the 

fuel’s use for motor vehicles has been difficult to segregate from its other uses. 

• EV charging sites continue to be available, especially in Arizona, California, and New 

York. 

• E85, biodiesel, EV, and LPG fueling facilities are generally open to the public. 

• LNG, CNG, and hydrogen stations are less likely to be publicly available. 

Laws and Incentives 

• Eighty percent of federal alternative fuel laws and incentives (L&I) appear as tax 

incentives and grants. 

• Tax incentives and grants account for more than half of all combined federal and state 

L&I that have been enacted. 

iii
• When laws and incentives are classified by regulation type, about 60% are for vehicle 

acquisition requirements, fuel tax breaks, and vehicle registration requirements. 

• There has recently been a sharp increase in L&I related to ethanol and biodiesel, most 

likely stemming from the Energy Policy Act of 2005 and the increased popularity of 

these fuels. 

• When classifying by user type, fully one-third of all L&I are aimed at fleets; another onesixth of the current L&I benefit individual consumers. 

The Clean Cities Program 

• Officially started in September 1993; Atlanta, Georgia, was the first Clean Cities 

coalition. 

• At the end of FY 2006, there were 90 coalitions with more than 4,400 stakeholders. 

• The geographic area covered by Clean Cities coalitions includes about two-thirds of the 

U.S. population, based on the 2000 U.S. Census. 

• The three states with the greatest population (California, Texas, and New York) have 

more than 25% of the coalitions (26/90). 

• Fourteen states have state-wide coalitions. 

• Five states (Alaska, Mississippi, Montana, Nebraska, and South Dakota) currently have 

no Clean Cities coalitions. 

National Alternative Fuels and Clean Cities Hotlines 

• The National Alternative Fuels Hotline began answering queries in 1991; the Clean Cities 

Hotline came online in 1993. 

• The Hotlines have handled more than 95,000 requests through FY 2006. 

• More than 1 million documents have been distributed in response to Hotline requests. 

• At its peak in FY 2000, the Hotline handled almost 11,000 requests. 

• With the consolidation of DOE’s Hotlines to the Energy Efficiency and Renewable 

Energy Information Center (IC) in FY 2006, the Hotline Service was converted to a 

Technical Response Service to handle only higher level inquiries passed on by the IC. 

• Before FY 2000, almost two-thirds of people heard about the Hotline through the 

Internet. After FY 2000, the proportion increased to 90%. 

• In 2005 requests for information about ethanol, biofuels, and biodiesel reached about 

60% of all requests when a request was classified by fuel type. 

• CNG interest dropped from 16% of fuel requests in FY 2004 to 9% in FY 2005; biodiesel 

requests increased from 18% to 29% in the same time period. 

• More than one-third of all fuel type requests were about ethanol in FY 2004 and FY 2005. 

• Hotline requests received electronically doubled in proportion (about 20% to 40%) from 

FY 1997 to FY 2005. 

• From direct user feedback received over the years, the Hotline has received very high 

grades for its operators, the service provided, and the responses having met or exceeded 

expectations. 

iv
Acronyms 

AFDC Alternative Fuels Data Center 

AFV alternative fuel vehicle 

AGA American Gas Association 

AMFA Alternative Fuels Motor Act of 1988 

CNG compressed natural gas 

DOE U.S. Department of Energy 

E85 fuel blend of 85% ethanol with 15% gasoline 

EPAct Energy Policy Act 

EV electric vehicle 

FEG Fuel Economy Guide 

FFV flexible-fuel vehicle 

FY fiscal year 

GEM Global Electric Motors 

HEV hybrid electric vehicle 

IC Energy Efficiency and Renewable Energy Information Center 

L&I laws and incentives 

LDV light-duty vehicle 

LPG liquefied petroleum gas 

MY model year 

NAFH National Alternative Fuels Hotline 

NBB National Biodiesel Board 

NEV neighborhood electric vehicle 

NEVC National Ethanol Vehicle Coalition 

NREL National Renewable Energy Laboratory 

OEM original equipment manufacturer 

SUV sport utility vehicle 

TEDB Transportation Energy Data Book 

TRS Technical Response Service 

 v
Background

Alternatives to gasoline and diesel fuels have been investigated and used for more than a 

century; however, not since the electric automobiles of the late 1800s and early 1900s have any 

serious challenges been posed to the gasoline or diesel internal combustion engine. In the lightduty vehicle (LDV) sector, gasoline use has predominated, especially stimulated by Henry 

Ford’s mass production of the gasoline-powered Model As and Ts that propelled the industry for 

the next century. The LDV industry continues to be dominated by the gasoline internal 

combustion engine. However, because of our nation’s growing demand for petroleum in the 

transportation sector, the increasing instability of supply guarantees, and the rising global 

demands for oil by developing nations, alternatives to a petroleum-based transportation industry 

are being vigorously explored in both the industrial and the governmental sectors. 

The prime legislative mover that led to the current alternative fuel movement began with the 

1988 Alternative Motor Fuels Act (AMFA). AMFA contained provisions to formally establish 

an Alternative Fuels Data Center (AFDC). According to the National Highway Traffic Safety 

Administration in its discussion of AMFA: 

The AFDC was created to facilitate the directives of AMFA. The purpose of the AFDC is 

to gather and analyze information on the fuel consumption, emissions, operation, and 

durability of alternative fuel vehicles, and to provide unbiased, accurate information on 

alternative fuel vehicles to government agencies, private industry, research institutions, 

and other related organizations. 

AMFA provided incentives for the original equipment manufacturers (OEMs, i.e., Chrysler [now 

DaimlerChrysler], Ford, and General Motors) through corporate average fuel economy credits. 

Follow-on legislative activities mandated the use of alternative fuel vehicles (AFVs) in 

increasing proportions over time by federal, state, and fuel provider fleets as a result of the 

national Energy Policy Act of 1992 (EPAct). EPAct further expanded the requirements for data 

and information to support regulated fleets and established the requirements for a voluntary 

program, which led to the Clean Cities Program. Additional federal executive orders added 

strength to this legislation by mandating the use of the alternative fuel in vehicles, in the case of 

non-dedicated fuel systems. 

Since its inception in the fall of 1990, the AFDC has played a major role in tracking information 

about alternative fuels and AFVs. The AFDC has made information available to industry, 

government, and the public about AFVs offered each model year. Through a variety of 

cooperative and subcontracted efforts, a database of alternative fuel refueling sites with mapping 

capabilities has also been offered from 1991 to the present. In addition, information about 

industry-related laws and incentives (L&I) has been made available on federal and state levels 

since the mid-1990s. 

The AFDC is available to the public through the AFDC Web site, which offers a wealth of 

additional information, including a clean fleet guide for fleet managers, fuel property comparison 

charts, a variety of toolkits (e.g., the E85 Fleet Toolkit and the Hybrid Vehicle Toolkit), 

alternative fuels training, educational resources, related links, industry contacts, frequently asked 

questions, a searchable document database, and a link to the Clean Cities Web site, which offers 

 1
all programmatic details about Clean Cities and its contributions to reducing our dependence on 

imported petroleum. The information in the AFDC and Clean Cities Web sites can be found at 

http://www.eere.energy.gov/afdc/ and www.eere.energy.gov/cleancities/, respectively. 

Information about EPAct regulations and implementation can be found at 

www.eere.energy.gov/vehiclesandfuels/epact. 

Report Objective 

This report uses the wealth of information contained in the AFDC databases to assess and 

describe historical trends in the alternative fuels industry. The objectives of this report are to: 

• Document the development of the alternative fuels industry as reflected in AFDC data. 

• Analyze information and trends from the AFDC that may prove valuable in 

understanding past perspectives that could help advance the current and newly emerging 

technology market. 

The prime indicators of growth, interest, and emphasis in the alternative fuels industry can be 

found by exploring historical trends as reflected in OEM vehicle model data and AFV fueling 

station growth and decline. 

The report analyzes information from the following AFDC databases: 

• OEM Vehicle Offerings – primarily LDV information 

• AFV Refueling Stations 

• Laws and Incentives 

• National Alternative Fuels Hotline and Clean Cities Hotline Caller/Requester, Request, 

and User Feedback Databases 

• Clean Cities Coalition Information 

Acknowledgments 

The AFDC has been supported by DOE’s Clean Cities activity within the FreedomCAR and 

Vehicle Technologies Program. Additional funding has been provided by FCVT’s EPAct 

Regulated Fleet activities for resources of particular relevance to regulated fleets. In addition to 

the support from the U.S. Department of Energy, the AFDC has benefited from contributions of 

data, information, and feedback from countless industry groups and individuals in the alternative 

fuels community. 

 2
Light-Duty Original Equipment Manufacturer Vehicle Offerings

Original Equipment Manufacturer Models Offerings 1991 to 2006 

The AFDC has made OEM product offerings available since 1991, beginning with the 65 

methanol flexible-fuel vehicle (FFV) Ford Tauruses and Chevy Luminas offered that year at four 

federal fleet locations in partial response to AMFA 1988. These were not the first AFVs tested 

and analyzed at the federal level. From 1985 through 1987 Lawrence Berkeley National 

Laboratory, Argonne National Laboratory, and Oak Ridge National Laboratory also collected 

performance data about M85 and M88 FFVs as part of the Alternative Fuels Utilization Program. 

Those beginnings, AMFA 1988, and EPAct 1992, along with a few presidential executive orders, 

launched the foray into a host of LDV alternative fuel and vehicle combinations from 1991 to 

present. 

 

Since 1991, 390 AFV and 31 hybrid-electric vehicle (HEV) models have been offered by all 

OEMs combined. Recent trends will be subsequently examined, but the Big Three U.S. 

automakers (DaimlerChrysler, Ford, and General Motors) have accounted for four of five vehicle 

models offered since 1991 (see Figure 1). Ford has led the way with one-third of all models 

offered by all manufacturers. Entering into the alternative fuels and HEV arena beginning in 

1998, Toyota and Honda have accounted for about one of 10 models offered. Additional 

discussion on these generalities will follow as more details are provided in later charts. 

Figure 1. Light-Duty OEM AFV/HEV Models Offered 

1991-2006

FORD

34%

CHRYSLER

18%

OTHER

10%

HONDA

6%

TOYOTA

5%

GM

27%

FORD

GM

CHRYSLER

OTHER

HONDA

TOYOTA

Figure 2 is a follow-on chart that presents a historical timeline detailing the number of models 

offered by each OEM. Ford showed steady growth in its offerings of compressed natural gas 

(CNG) vehicles and FFVs through 2004, having peaked in 1999 with 19 models. Ford’s dramatic 

decline in the number of models offered between 2004 and 2005 represents its decision to no 

longer offer CNG vehicles. In 2005 Ford made its entry in the hybrid market with the Escape, 

and continues to offer FFVs. 

 3
Figure 2. AFV/HEV Models Offered by OEMs 1991-2006

0

2

4

6

8

10

12

14

16

18

20

# of Models Offered

CHRYS

FORD

GM

HONDA

TOYOTA

Others

Because of negative publicity that seemed to be related to CNG tank cylinder problems (later 

determined not to be the cause), GM pulled out of the AFV market for a three-year period from 

1994 to 1996. Since that time GM has demonstrated a diversified commitment to alternative 

fuels and the Clean Cities Program, and sales of all the AFVs have experienced steady growth 

since 1996. GM was the last U.S. OEM to produce a CNG vehicle, having discontinued its CNG 

models after MY 2006. Honda, with its Civic GX, is the only other manufacturer offering a CNG 

model in 2006. 

DaimlerChrysler has also been a major contributor to the alternative fuels market, with its peak 

offerings in the 1999 to 2003 timeframe, when it manufactured CNG, E85, and electric vehicles 

(EVs). By 2006 DaimlerChrysler offerings were limited to a variety of FFV models. 

Honda and Toyota have been in the AFV and HEV markets since 1998. Both have had entries in 

the CNG market (Toyota’s Camry and Honda’s Civic GX), but only Honda’s Civic GX remains. 

Honda and Toyota have also had EVs in the market, but now concentrate their offerings in the 

HEV arena. The Honda Insight and the Toyota Prius HEVs first hit the market in the 2000 model 

year. The Toyota Prius sedan sales far outstripped the two-seater Insight, which was 

discontinued in 2006. The first sport utility vehicle (SUV) hybrids were the Ford Escape (the 

first U.S. OEM hybrid) and the Toyota Highlander, offered initially in 2005. 

Original Equipment Manufacturer Offerings by Fuel Type, 1991 to 2006 

Our analysis continues with the examination of the fuel types of the models offered by the 

OEMs. We’ve seen that the Big Three have offered the greatest number of models since 1991, 

but is there a difference between the U.S. manufacturers and others, such as Toyota and Honda, 

with regard to fuels on which they’ve chosen to concentrate? Figure 3A shows the numerical 

distribution of models offered from 1991 to 2006 by manufacturer and vehicle fuel type. The Big 

Three have concentrated on CNG and E85 over the years. But we’ll later present information that 

 4
shows the decline in the interest of CNG as a fuel offering among the Big Three because of lack 

of infrastructure development and the incremental production costs of CNG vehicles. Honda and 

Toyota have concentrated on HEVs, EVs, and CNG vehicle offerings. Only Honda and GM 

remained in the light-duty CNG market in 2006. The “Other” category includes Mazda, 

Mercedes, Nissan, Quantum, and Solectria; only Nissan is still in the AFV ballgame in 2006 with 

an FFV offering. 

0

20

40

60

80

100

120

140

160

# of Models

Chrysler Ford GMC Honda Toyota Other

Figure 3A. AFV/HEV Models by OEM/Fuel Type 1991-2006

M85

LPG

Hybrid

EV

E85

CNG

0%

20%

40%

60%

80%

100%

Chrysler Ford GMC Honda Toyota Other

Figure 3B. AFV/HEV Models by OEM/Fuel Type 1991-2006

M85

LPG

Hybrid

EV

E85

CNG

 

Figure 3B is based on the same data as Figure 3A, but provides a clearer representation of the 

proportional distribution of vehicle/fuel type offered by each manufacturer from 1991 to 2006. 

 5
More than anything this chart reflects the Big Three reaction to the demands placed on fleets to 

purchase AFVs as a result of EPAct 1992. Through the 1990s the only vehicles coming to the 

market were CNG, FFVs (E85 and M85), LPG, and EVs; the emphasis was on CNG and alcohol 

fuel vehicles. Hence, the Big Three not surprisingly show much greater proportions of CNG and 

FFV vehicles than the latecomers—Honda and Toyota—who introduced the first hybrids in 

2000. 

Because CNG and E85 were the primary vehicle fuel choices through most of the 1990s, it is not 

unexpected to find that the greatest number of model choices over the years concentrated on 

these two fuels. Where Figures 3A and 3B show the number of vehicle models offered by fuel 

choice and OEM, Figure 4, a reversal of the axes in Figures 3A and 3B, is provided here to 

provide a better visualization of the fuel emphases shared by the OEMs since 1991, rather than 

the OEM offerings by fuel type. Figure 4 clearly shows the emphasis that the OEMs have 

historically placed on CNG and E85. Appendix I provides the raw data that were used to 

generate Figures 1 to 4. 

 

0

20

40

60

80

100

120

140

160

# of Models

CNG E85 EV Hybrid LPG M85

Figure 4. AFV/HEV Models by Fuel Type/OEM 

1991-2006

Other

Toyota

Honda

GMC

Ford

Chrysler

Figure 5 represents the proportional distribution of fuel types offered by OEMs from 1991 to 

2006. The figure further shows that Toyota and Honda have dominated the HEV market over 

time and the Big Three have dominated the CNG and E85 markets, as well as the early LDV 

M85 and LPG markets, which are no longer players in the light-duty AFV sector. All OEMs 

have participated in the development of the EV market, but that role has diminished in 2006 to a 

neighborhood electric vehicle (NEV) niche, dominated by Global Electric Motorcars (GEM), 

LLC, a DaimlerChrysler company. 

 6
0%

20%

40%

60%

80%

100%

CNG E85 EV Hybrid LPG M85

Figure 5. AFV/HEV Models by Fuel Type/OEM 

1991-2006

Other

Toyota

Honda

GMC

Ford

Chrysler

So far we’ve looked at aggregate data spanning 1991 to 2006. But what does the AFV market 

look like in 2006? To determine this, we’ll examine 2006 OEM models offered by fuel type, as 

shown in Figure 6. This picture represents a significant deviation from the full historical 

offerings of Figure 3A. First, no OEM in MY 2006 offered an EV, M85, or LPG vehicle; only 

GM and Honda offered CNG vehicle models. The rest are E85 FFVs and HEVs. Chrysler’s six 

models are all E85; 75% of Ford’s eight vehicles are FFVs. In 2006 GM is the only OEM to 

offer all three vehicle fuel types and leads the way with 15 models. Toyota was 100% committed 

to the hybrid line in 2006. Neither Honda nor Toyota has ever offered an alcohol fuel or LPG 

vehicle. 

6

6

2

4

9

2

1

3

4 1

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Chrysler Ford GMC Honda Toyota Other

Figure 6. OEM AFV/HEV Models Available 2006

Hybrid

E85

CNG

 

 7
Recent Trends in Alternative Fuel Vehicle/Hybrid Electric Vehicle Offerings 

Four additional charts shed light on the more recent trends of vehicle offerings in the AFV/HEV 

arenas. First, in Figure 7, we’ll analyze vehicle fuel type trends from 1998 to 2006. The 

following information is noteworthy: 

• E85 model offerings showed a relatively steady growth from 1998 to 2006. 

• Hybrid models (10) in 2006 are double the number of CNG models offered (five). 

• Only hybrid and E85 models are showing growth trends. 

• In 2005 and 2006, no LPG or EV models were offered. 

Figure 7. AFV/HEV LDV Model Offerings by Fuel Type 1998-2006

0

5

10

15

20

25

30

1998 1999 2000 2001 2002 2003 2004 2005 2006

# of Models Offered.

CNG Ded./Bi-Fuel

E85

EV

Hybrid

LPG Ded./Bi-Fuel

Figure 8 combines all AFV models and compares AFV models offered with HEV models from 

2000 to 2006. Whereas AFV offerings reached their peak in 2002 with 45 models, the HEV 

market has shown significant growth from 2004 to 2006. Depending on the infrastructure growth 

for E85 and market demand for HEVs, the HEV model offerings might well surpass the number 

of FFV (E85) models offered in the not-too-distant future. 

We’ve looked at vehicle models offered by OEMs with regard to fuel type over time. But what 

kinds of vehicle types (autos, pickups, vans, SUVs) in the light-duty arena have been offered by 

the OEMs from 1991 to 2006? Figure 9 provides the answers. 

Some notable trends are: 

• Autos and pickups continue to dominate today’s market with more than 70% of the 

vehicle offerings in 2006. 

• SUVs show significant proportionate growth since 2002 and now garner about onefourth of the offerings by all OEMs. 

 8
• The interest in vans has dropped since the higher concentrations of CNG van 

offerings in the 1999 to 2003 timeframe; vans now represent only 5% of the 2006 

model offerings. 

Details of models offerings by specific OEM are offered in Appendix II. 

Figure 8. AFV vs. Hybrid OEM Models 2000-2006

0

5

10

15

20

25

30

35

40

45

50

2000 2001 2002 2003 2004 2005 2006

# of Models Offered.

AFVs

Hybrids

Figure 9. OEM AFV/HEV Models By Vehicle Type 1991-2006

50

45 SUV

40 Van

Pickup 35

Auto

# of Models 30

25

20

15

10

5

0

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

 

Hybrid Sales Growth 

As shown in Figure 10, HEV sales have experienced dramatic exponential growth, both in 

numbers and in the increasing diversity of vehicle models coming online. Since their 

 9
introduction in 2000 with the Honda Insight and Toyota Prius, total hybrid sales are approaching 

650,000; at least 10 hybrids are now on the market from Ford, Honda, and Toyota. In 2006, 

annual sales figures are expected to be somewhere between 230,000 and 250,000 units. 

0

50,000

100,000

150,000

200,000

250,000

# of Hybrids Sold.

2000 2001 2002 2003 2004 2005 2006*

*2006 estimated from 1/2 year sales of 116,994 units. 

Source: Green Car Congress 

Figure 10. U.S. Hybrid Vehicle Sales 2000-2006

The Green Car Congress (www.greencarcongress.com) provides monthly updates on the number 

of hybrids sold by manufacturer and model. Figure 11 from the Green Car Congress provides a 

picture of the growth of HEV sales from 2004 to 2006. On a monthly basis, hybrid sales have 

steadily increased since February 2006; August sales reached the highest ever at 26,189 units, 

representing 1.8% of all LDVs sold in that month. Toyota’s Prius and Camry hybrids garnered 

three-fifths of the hybrid sales in August 2006. 

Parenthetically, EPAct 2005, Section 706, establishes a “Joint Flexible Fuel/Hybrid Vehicle 

Commercialization Initiative” under which “The Secretary shall establish a program to improve 

technologies for the commercialization of--

(1) a combination hybrid/flexible fuel vehicle; or

(2) a plug-in hybrid/flexible fuel vehicle.” 

As a result of this stimulus (paragraph [1] above), Ford is already developing an FFV option to 

the HEV Escape vehicle. At the 2006 Washington, D.C., auto show, Ford unveiled, with great 

fanfare, its prototype for an E85-powered Escape Hybrid vehicle. Ford’s overall marketing plans 

for this vehicle are as yet unclear. 

 10
Figure 11. 

Used with permission of Green Car Congress. 

 11
Fueling Station Analysis 

Introduction 

The growth of the alternative fuels industry has, in some ways, been mirrored by the rise (and 

fall in some cases) of the number of fueling stations it has created. The growth of fueling stations 

will now be examined to see what can be learned about their effects on the alternative fuels 

industry. For the most part, the historical data have been taken from the data published in the 

Transportation Energy Data Book (TEDB) by Oak Ridge National Laboratory; the source of this 

information is the AFDC at NREL. The reason for using the data published in TEDB is that they 

represent a published snapshot in time of the data from the AFDC. We have chosen to present 

fueling station data from 1998 as the most reliable set of data on fueling stations over time, 

because of the more rigorous data validation efforts that have taken place since that date. 

Fueling Station Database Validation 

NREL has been cognizant of the need to maintain data that have been verified and are as 

complete as possible under the constraints of reasonable resources applied to data quality 

assurance. Over the years NREL has employed various subcontractors to collect and validate 

fueling site data sources. All stations in the NREL database have been directly contacted, either 

by phone or e-mail, or through secondary sources to ensure that the stations are open and still 

distributing the noted alternative fuel for motor fuel use. 

Differences in data sets between NREL and other sources and Web sites are noted and explained 

for the special cases of E85 and biodiesel fueling sites. The National Ethanol Vehicle Coalition 

(NEVC) maintains a state-by-state list of E85 fueling stations, showing a total count of 979 

stations when visited on October 1, 2006. NREL’s database included 906 stations on the same 

date. The primary difference between the NREL and the NEVC counts is that the NEVC reports 

planned stations in addition to those in actual service. In a similar fashion the National Biodiesel 

Board (NBB) maintains a list of stations offering biodiesel (B2-B100), as does NREL. As NEVC 

does with E85, NBB includes planned stations. 

Verifying the stations offering LPG (propane) as a motor fuel has always been difficult. The 

original database of more than 5,000 LPG sites offering LPG motor fuel came from a directory 

of LPG stations published by the National Propane Gas Association in the mid-1990s. Over time, 

NREL’s investigations into these stations have shown that many have discontinued the practice 

of offering LPG as a motor fuel. In the early to mid-1990s the LP Gas Association estimated that 

10,000 propane stations offered propane as a motor fuel, although this complete list of stations 

was never published for verification. 

Regarding natural gas fueling facilities, NREL subcontracted with the American Gas Association 

(AGA) from the early to mid-1990s for use of its published stations offering CNG. The list was 

limited to AGA members and suffered somewhat from a lack of annual station verification. 

NREL felt more confident once the stations were directly contacted on an annual basis beginning 

in the late 1990s. 

 12
Fueling Station Database Analysis 

Because of the increasing confidence of data integrity from the late 1990s, the analysis of 

stations offering alternative fuels is made beginning with 1998 and extending through 2006. The 

data are reported on a fiscal year (October 1 to September 30) basis. Figure 12 summarizes the 

growth of alternative fuel refueling sites from 1998 to 2006. LPG sites are not included for two 

reasons: (1) to report the data would diminish the graphical representation of the other refueling 

sites; and (2) no OEMs are manufacturing LPG vehicles (and the number of LPG vehicles 

generally stems from estimates made by the Energy Information Administration in the early to 

mid-1990s with revisions as appropriate). And there have never been any reliable methods to 

estimate national use of LPG, except from the vehicle estimates. One could raise a similar 

question about including electric sites in the graph, but the argument for including these sites is 

that they are verifiable, although the use of the sites is not determinate and only NEVs are 

currently being manufactured and sold by one OEM (GEM), as noted above. The electric 

charging sites are predominantly in California, Arizona, and New York. 

 

0

500

1,000

1,500

2,000

2,500

3,000

# of Stations

1998 1999 2000 2001 2002 2003 2004 2005 2006

Figure 12. AFV Refueling Sites by Fuel Type 1998-2006

H2

BD

ELEC

LNG

CNG

E85

One of the most apparent features of the data presented in Figure 12 shows the steady decline of 

CNG sites since 1998 and dramatic increase of ethanol sites, especially from 2004 to 2006. The 

significant growth of the biodiesel sites reflects the growth and use of biodiesel as an alternative 

fuel, predominantly in the heavy-duty industry today. Of course, the 6 to 7 million ethanol 

vehicles on the roads in the United States today and EPAct 2005 (which established the 

Renewable Fuels Standard to produce 7.5 billion gallons of ethanol by 2012) easily justify the 

growth of E85 refueling sites. The number of stations offering biodiesel might be expected to 

experience more rapid growth in the next five years because biodiesel is more commonly sold as 

a low-level blend of 2% to 5%; sales in the 20% blend have also increased in popularity. Anchor 

fleet stations for CNG (mostly in the heavy-duty and public transportation markets such as taxis 

and airport shuttles sectors) are on the increase, but the steady decline of CNG stations in general 

derives from very few OEMs presently offering light-duty CNG vehicles. 

 13
Figure 13 shows the total number of U.S. refueling stations in 2006, including LPG. By NREL’s 

best authentication processes, there were 5,256 alternative fuel refueling sites in the United 

States as of September 30, 2006. LPG sites represented about half of the sites, E85 about onesixth, CNG about one-seventh; biodiesel and electric sites fewer than one-tenth each, and LNG 

and hydrogen comprising fewer than 1% each of all sites. 2,570 906 736 520

454

39

31

0

500

1,000

1,500

2,000

2,500

3,000

# of Stations

LPG E85 CNG BD ELEC LNG H2

Figure 13. Refueling Sites By Fuel Type 2006

Figure 14 displays the comparative growth and decline of the E85, biodiesel, and CNG markets 

as represented by the number of stations from 1998 to 2006. Figure 14 illustrates the market 

trends previously alluded to: (1) the declining CNG market because of OEM lack of commitment 

to manufacture light-duty CNG vehicles; and (2) the legislatively stimulated and growing 

markets of E85 and biodiesel. In 2006, the number of E85 stations (906), growing by almost 

85% from 2005 to 2006, surpassed the CNG station count (736), which once numbered more 

than 1,400 in the 1996 to 1997 timeframe according to the AGA data stored in the AFDC and 

reported in the TEDB. Based on trends indicated in Figure 14, the number of biodiesel stations 

will also surpass the number of CNG stations in 2006 or 2007. 

Public/Private Refueling Site Analysis 

Refueling stations may be open to the public part- or full-time, or they may be solely available to 

the owners of the station on private locations. Many stations on government property may also 

not be open to the public. Figure 15 offers the proportions of public to private stations by fuel 

type in 2006. The salient features of this figure are: 

• Most LPG stations have always been open to the public. 

• To service the millions of publicly owned FFVs on the road, E85 stations are most 

often open to the public. 

• Almost 80% of electric charging sites have been open to the public historically. 

• More than two-thirds of the biodiesel stations are open to the public as part of normal 

highway diesel service operations. 

 14
• LNG, CNG, and hydrogen stations are more often located on private property to 

service large anchor niche market fleets, or fledgling prototype markets in the case of 

hydrogen. 

Figure 14. E85, Biodiesel, & CNG Station Trends 1998-2006

0

200

400

600

800

1,000

1,200

1,400

1998 1999 2000 2001 2002 2003 2004 2005 2006

# of Stations

E85

CNG

Biodiesel

0%

20%

40%

60%

80%

100%

E85 CNG LNG ELEC BD H2 LPG

Station Type

Figure 15. Public/Private Proportions of Refueling Stations 

by Fuel Type in 2006

Private

Public

Station Owner Type 

Alternative fuel station growth has been largely influenced by private entrepreneurs. Recent 

grant incentives for partially funding alternative fuel station capital investments have also 

contributed to station openings. Figure 16 clearly shows that 80% of all alternative fuel refueling 

 15
stations are privately owned; another 10% are owned by the government, and the rest by a utility 

or some joint ownership venture. Although 80% of the stations are privately owned nationwide, 

85% of all alternative fuel stations are open to the public, largely influenced by the significant 

proportions of the LPG, E85, and biodiesel stations open to the public as noted in Figure 15. 

Figure 16. 2006 Alternative Fuel Stations by 

Ownership Type

Gov't

10%

Joint

2%

Utility

8% Private

80%

 16
State and Federal Laws and Incentives 

Because of the demand for information about L&I at the state and federal levels, legislative 

actions have been tracked and made available to the public in the AFDC. Over the past decade, 

NREL has maintained data on federal and state L&I through a subcontracting process. 

This section is offered primarily to show the breadth and depth of the information that is offered 

within the AFDC. It is not intended to analyze the specific contents of passed legislation, but to 

discuss the robust ways the data are organized, categorized, and made available to the public. 

The information on the Web is divided into federal and state-by-state bases, and is further made 

available by the following classifications: 

• Incentive type (grants, tax incentives, loans, rebates, etc.) 

• Regulation type (acquisition requirements, fuel taxes, etc.) 

• Technology/fuel type (general alternative fuels, biodiesel, ethanol, hydrogen, etc.) 

• User type (fleet manager, alternative fuel producer/dealer/OEM, etc.) 

• Multi-parameter search capability (refinements of above). 

Hundreds of L&I have been enacted at the federal and state levels. The AFDC provides 

information on all currently active legislation and regulations. The details of any searches on the 

Laws and Incentives Web site, for the first four specific categories noted above, results in a table 

that details the number of regulatory activities that have been enacted at the federal and state-bystate levels for each option in the selected category. Once a search is made, the user may click on 

any number in the summary table to view the details of the legislated activity. Searches may be 

conducted at: www.eere.energy.gov/afdc/laws/incen_laws.html. One piece of legislation may fall 

into several categories. That is, for example, the user may see the same legislative activity 

referenced in the details of different searches within the same state or category. 

 

We will now examine summary information about the number of L&I that are currently 

categorized in one of the searchable areas: incentives types, regulation types, technology/fuel 

types, and user types. 

Figure 17 shows the proportions of incentive types that have been used to stimulate and grow the 

alternative fuels market. Tax incentives and grants have led the way with more than half (54%) 

of all legislative activity of these types at the combined federal and state levels. At the federal 

level, the importance that legislators placed on tax incentives and grants as the primary medium 

for advancing alternative fuels is noted in that four of five incentives were related to tax 

reductions or grant programs. At the state level, technical assistance and exemptions were found 

to be important incentive types. Currently 317 laws or regulations deal with various incentive 

types. Of these, one-eighth have been passed at the federal level and seven-eighths at the state 

level. Only two states have no current legislation or regulations pertaining to at least one of the 

incentive types in Figure 17. California, Connecticut, New York, and Texas all have more than 

10 laws or regulations related to one of the listed incentive types. 

 17
88

13

50

20

39

3

41

1

19

3

20

0

11

0

9

0

0

20

40

60

80

100

120

# of Laws & Incentives

Tax Incentives

Grants

Tech. Assistance

Exemptions

Loans/Leases

Rebates

Fuel Discounts

HOV Lane

Figure 17. Federal and State Laws and Incentives 

by Incentive Type (2006)

Federal

State

The second way the AFDC has classified legislation is by the regulation type or sectors affected 

by adopted legislation. Figure 18 presents the data on federal and state activities that have been 

specifically enacted to affect particular areas listed on the chart. In general the federal regulations 

have concentrated most of their efforts on vehicle acquisition requirements (EPAct 1992 

especially focused on acquisition requirements); five of the eight enactments fall into this 

category. State efforts have been heavily concentrated in three areas; 60% of L&I affect 

acquisition requirements, fuel tax regulations, and vehicle registration. 

Most legislative and regulatory activities were easily classifiable into multiple fuel/technology 

categories, as suggested by the data in Figure 19. AFDC personnel were able to categorize L&I 

by fuel/technology type into 894 entries, of which 812 represented state activities and 82, 

federal. (See supplemental tables in Appendix III.) General alternative fuel impacts led the way 

numerically, but we may safely assume that these laws and regulations would also result in being 

classified in one of the other specific alternative fuel/technology categorizations listed in Figure 

19. Suffice it to say that there has been significant activity, and more overall specific fuel 

diversity at the state level than at the federal level; the most significant currently active laws and 

incentives affect EVs/NEVs, biodiesel, natural gas, and ethanol. Of course, the greater diversity 

of L&I at the state level would be expected with 50 entities contributing. 

 18
58

5

51

0

46

0

24

1

24

0

22

0

11

1

7

1

0

10

20

30

40

50

60

70

# of Laws & Incentives

Acq. Req'ts

Fuel Taxes

Reg. Req'ts

Driving Restr.

Idle Reduct.

Econ. Devel.

Fuel Prod.

Emis. Inspect.

Figure 18. Laws & Incentives by Regulation Type (2006)

Federal

State

163 17

101 6

96 6

92 1

80

4

47 14

57 2

55 1

50

4

19 17

28 8

23 3

0

20

40

60

80

100

120

140

160

180

# of Laws & Incentives

Alt Fuels

EVs/NEVs

Biodiesel

Natural Gas

Ethanol

Emissions

AF Blends

LPG

HEVs

Fuel Effic.

Idle Reduct.

H2/Fuel Cells

Figure 19. Laws & Incentives By Fuel/Technology (2006) 

Federal

State

 19
Figure 20 provides a detailed look at L&I by fuel type/technology over time. The main points to 

be gleaned from this chart are: 

• A general decline in L&I related to natural gas. 

• A sharp increase in L&I related to ethanol and biodiesel that stems most likely from 

EPAct 2005 and the current growth in the popularity of these fuels. 

• L&I affecting idle reduction came on the books between 2004 and 2006. 

• General L&I covering all alternative fuels show gradual decline as L&I become more 

fuel specific in recent years. 

• And 2005 was a big year in total L&I because of EPAct 2005. 

0

20

40

60

80

100

120

140

160

180

200

# of Laws and Incentives.

Pre20012001 2002 2003 2004 2005 2006

Figure 20. L&I By Fuel/Technology by Year

Nat. Gas

LPG

Idle Reduc.

Hydrogen

HEVs

Elec Veh's

Ethanol

Emissions

Efficiency

Blends

Biodiesel

All AF

We will now examine the types of user groups for which L&I have been enacted. Figure 21 

shows that a great proportion of L&I have been geared toward influencing or mandating fleet 

managers to purchase AFVs. Fully one-third of all L&I are aimed at fleets. One-sixth of the 

current L&I benefit individual consumers; one of eight provides some type of incentive or grant 

for infrastructure development. More than one-fourth of the L&I benefit alternative fuel buyers, 

dealers, and producers. 

Appendix III contains some additional detailed information on the states having the greatest 

number of L&I and the general distribution of L&I by type (incentive, regulation, technology, 

and user). 

 20
308

17

136

31

101

16

89

6

78

5

76

4

26

4

20

7

3

7

0

50

100

150

200

250

300

350

# of Laws & Incentives

Fleet Mngr

Individual

Infrast. Oper.

AF Buyer

AF Dealer

AF Producer

AFV OEM

AF Research

TSE Oper.

Figure 21. Laws & Incentives by User Type (2006)

Federal

State

 21
The Clean Cities Program 

Background 

The Clean Cities Program and its sponsoring offices within DOE (currently DOE’s 

FreedomCAR and Vehicle Technologies Program) have funded NREL’s AFDC since 1990. The 

Clean Cities activity commenced in September 1993 with the designation of Atlanta, Georgia, as 

the first Clean City. In addition to AFDC support, Clean Cities funding has provided significant 

support for the National Alternative Fuels Hotline (NAFH) and Clean Cities Hotline since 

inception. Data from the hotlines will be examined later in this document. 

The Clean Cities Program is a voluntary public/private venture; 90 locations throughout the 

United States are currently designated as Clean Cities. Partnerships at the state and local levels 

form the foundation of Clean Cities (whose members are composed of state and local officials) 

and a diversity of industry and community organizations. Partnerships also take place at the 

national level through the program’s close relationships with OEMs, fuel providers, and other 

federal agencies and national associations. Coalitions are technology and fuel neutral and 

position themselves to be credible players to attract strong project partners. These project 

partners can in turn recommend and adopt the fuels and technologies best suited to opportunities 

in their communities. 

General Clean Cities Information 

At the end of FY 2006, Clean Cities numbered more than 4,400 stakeholders in its 90 coalitions. 

A map of the Clean Cities coalition locations can be found in Appendix IV. Figure 22 shows the 

population coverage of Clean Cities coalitions, based on 2000 U.S. Census data. In 2005, the 

geographic coverage of the 90 Clean Cities coalitions included a population of almost 180 

million people out of a U.S. population of some 281 million from the 2000 U.S. Census. This 

represents almost two-thirds of the U.S. population, affording the Clean Cities coalitions the 

ability to spread the word widely about AFVs and advanced technology vehicles. Because of the 

heavy proportion of population covered by Clean Cities, the growth of this coverage may well 

slow in the coming years. In addition, the Clean Cities Program funding has been limited in 

recent years, so the push to expand to more coalitions has not been a priority. 

Figure 23 presents some interesting data which demonstrate that the strength of Clean Cities 

organizations, as measured by the number of coalitions in each state, is not necessarily 

proportionate to the population of the state within which coalitions have been formed. In Figure 

23 the numbers on the bars represent the state population rank in the United States, so the three 

states with the greatest populations (California, Texas, and New York) would be expected to lead 

in the number of coalitions in that same rank order. The surprises come with the next three 

coalitions of Connecticut, Colorado, and Michigan, which have very low population rankings 

(especially Connecticut and Colorado), but high rankings in terms of the number of coalitions 

compared to the rest of the states. This demonstrates that some states can organize and network 

quite effectively despite their populations. However, 14 states have state-wide coalitions and, 

therefore, would have only one coalition to be counted. In 2006, only five states (Alaska, 

Mississippi, Montana, Nebraska, and South Dakota) have no Clean Cities coalitions. 

 22
Population Covered by Coalitions 

(2000 Census Data)

0

20,000,000

40,000,000

60,000,000

80,000,000

100,000,000

120,000,000

140,000,000

160,000,000

180,000,000

200,000,000

Sep-93Sep-94Sep-95Sep-96Sep-97Sep-98Sep-99Sep-00Sep-01Sep-02Sep-03Sep-04Sep-05

Figure 22. Population Covered by Clean Cities Coalitions (2000 Census Data) 

1

2

3

29 24 8

0

2

4

6

8

10

12

14

# of Coaltion

s

CA TX NY CT CO MI

Figure 23. States with >2 Clean Cities Coalitions

#s on bars refer to 

population rank in 

the US – 2000 

The bottom line is that the Clean Cities coalitions have been the vital outreach arm and active 

support branch of the national Clean Cities Program. Without these coalitions and their dedicated 

coordinators, there would be no Clean Cities Program. 

 23
The National Alternative Fuels and Clean Cities Hotlines 

Background 

AMFA 1988 provided authority to establish the AFDC (created officially at NREL in the fall of 

1990) and encouraged mechanisms to make information about alternative fuels available to the 

public. DOE was designated the government arm responsible to carry out both the provisions of 

AMFA 1988 and EPAct 1992, which added even more information dissemination 

responsibilities, lending justification to the important role the NAFH and Clean Cities Hotline 

have played since they were established in 1991 and 1993, respectively. The Hotlines, managed 

by NREL through a competitive subcontract, existed through the end of September 2005, when 

DOE consolidated its Hotline efforts with the formation of the Energy Efficiency and Renewable 

Energy Information Center (IC). The former Hotline service is now dedicated to providing only 

higher-level technical assistance as the Technical Response Service (TRS), responding mainly to 

questions forwarded by the IC that are above and beyond the expected expertise of that 

organization. 

NREL has had the responsibility to gather and store information from the Hotline subcontractor 

about the users (generically the “callers”) and the processed requests. Various FY beginning 

dates appear in the graphs because some data go back to the origin of the Hotlines, but Hotline 

data collection by NREL began in FY 1992, when it assumed managerial responsibility of the 

Hotline operation. Over the 15 years of the Hotline operations, more than 95,000 requests 

(Figure 24) were processed, resulting in more than 1 million documents (Figure 25) having been 

distributed since detailed document distribution statistics began to be maintained in 1995. These 

databases will now be analyzed to see what can be learned about the types of requests processed 

and the people who have used the system. 

Figure 24. Hotline/TRS Requests (FY92-06)

0 2,000 4,000 6,000 8,000 10,000 12,000

FY92

FY94

FY96

FY98

FY00

FY02

FY04

FY06

Requests Processed (95,065 thru FY06)

 24
Hotline requests grew dramatically from its inception in 1992 through 1996, showed a significant 

decline in 1997, then a resurgence in 1998. Requests peaked in 2000, declined significantly from 

2000 to 2004, increased slightly in 2005, then dropped significantly in 2006. The explanations 

are: 

• From 1992 to 1998 an anticipated increase in the toll-free 800 service was expected as 

the word spread and the increase in alternative fuels, vehicle models, and infrastructure 

continued to grow. We suspect that there really was not a decline in the number of 

requests handled in FY 1997, but that the reporting of all requests may have lapsed 

toward the end of FY 1997 when the Hotline was in a transition to a new subcontractor. 

• By 1998, the number of people and organizations becoming Web savvy was increasing 

rapidly so inquiries, as anticipated and expected, began to be answered using Web 

information and its increasing search engine capabilities, making it easier for users to ask 

their questions over the Web, with no additional (Hotline) intervention necessary. 

• The pickup in request processing from 1999 to 2002 can be explained by a large number 

of requests for copies of the Fuel Economy Guide (FEG), which were processed by the 

Hotline during those years. 

• The number of requests continued to drop in 2003 and 2004 as the FEG distribution 

system was automated and moved away from Hotline handling. 

• The slight resurgence in requests in 2005 stemmed from questions related to the newly 

passed EPAct 2005 legislation. 

• FY 2006 began the new TRS. This meant that all requests first went to the IC, which only 

forwards to the TRS those inquiries that are at a technical level not expected to be 

answered by the IC. So, the sharp decrease in request processing in FY 2006 was fully 

expected. 

Figure 25 presents the picture for documents distributed from FY 1996 to FY 2006. The peaks 

from 1999 to 2002 included distribution of more than 400,000 copies of the FEG. In 2003 the 

distribution of FEGs was automated and no longer handled by the Hotline. In FY 2006, the 

Hotline service changed to the TRS, as discussed above, so documents were distributed only by 

the IC. 

How did people learn about the Hotline? Figure 26 answers that question. Over the years 64% of 

the way people learned about the Hotline was through the Internet. This percentage has increased 

to 90% since FY 2000. Newsletters and industry publications have accounted for one-sixth of the 

referrals historically. 

 25
0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000

450,000

# of Docs. Distributed.

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

Figure 25. Hotline Docs Distributed FY96-FY06

Figure 26. Hotline Referral Types 1995-2006

9% 64%

8%

5%

5%

5% 4%

Internet

Newsletters

Industry Pubs

DOE HQ

Fed/St/Local Orgs

NREL

Industry

Hotline Request Processing and Evaluation – the Details 

We will now examine the details of the Hotline operation, mostly from FY 1995 to FY 2005, as 

these are the full years for which data were collected and stored electronically from the Hotline. 

The details include: 

• Fuel type requests 

• Sources of requests – how received and by whom 

• Hotline feedback 

 26
• Request types – most popular topics 

• Fleet managers in database 

• State and country Hotline usage – Appendix V. 

 

Requests by Fuel Type 

Figure 27 presents the details of Hotline requests each year, classified by the caller’s fuel 

interest. 

Figure 27. Hotline Fuel Type Requests (FY95-05)

0% 20% 40% 60% 80% 100%

FY95

FY96

FY97

FY98

FY99

FY00

FY01

FY02

FY03

FY04

FY05

Biodiesel

Biofuels

Ethanol

Methanol

CNG

LNG

Electric

Fuel Cell

Hydrogen

Hybrid

LPG

The distribution of fuel interest from FY 1995 to FY 2005 has changed dramatically. We make 

the following observations from this chart: 

• From 1995 to 2005, the interest in LPG dropped significantly. 

• The interest in biodiesel has shown a steady increase since FY 1997. 

• The interest in ethanol has been fairly steady over time, and a dramatic increase came 

about in 2005 with the passage of the Renewable Fuels Standard and EPAct 2005. 

• In 2005, we see that almost three-fifths of the requests (where the fuel type was classified 

as part of the request) centered on biofuels or ethanol and biodiesel specifically. 

• The interest in CNG probably showed the most significant decrease from FY 2004 to FY 

2005, mostly because Ford stopped producing CNG vehicles. 

• Hybrid interest came to the forefront in FY 2000 with the advent of Toyota’s Prius and 

Honda’s Insight. The slight decline in HEV inquiries from FY 2004 to FY 2005 probably 

does not reflect a declining interest, but just the fact that they were catching on as noted 

earlier (Figures 10 and 11) by the continued increase in HEV sales, almost on a monthly 

basis. 

 27
• EV interest was relatively steady through FY 2001, then started to decline as the OEMs 

offered fewer and fewer options; only the GEM NEV was available in the EV market in 

2006. 

• Recent questions about methanol probably derived from the methyl tertiary butyl ether 

health concerns, as no methanol OEMs have been offered since 1997. 

Figure 28 summarizes the combined historical fuel request interests from FY 1995 to FY 2005. 

We can see from this chart that the historical summary is not reflective of today’s fuel interest. 

For the past 11 years, the largest proportion of fuel interest calls centered on CNG because of the 

large number of offerings by the OEMs, especially from 1995 to 2004. In 2005, Ford dropped 

out of the CNG LDV market and interest waned significantly. Over time, ethanol requests have 

represented about one-fifth of the requests; biofuels, biodiesel, and ethanol share one-third of the 

requests. LPG has garnered about one-eighth of all requests, but interest in LPG has dropped 

significantly in recent years, as no OEM LPG LDVs are on the market. 

Figure 28. Hotline Fuel Type Requests (FY95-05)

10%

5%

19%

4%

24%

3%

9%

3%

4%

6%

13%

Biodiesel

Biofuels

Ethanol

Methanol

CNG

LNG

Electric

Fuel Cell

Hydrogen

Hybrid

LPG

Figures 29 and 30 show the latest distribution of requests by fuel type from the last year of 

Hotline operation (FY 2005) and the first year of the TRS (FY 2006). The comparisons are 

interesting. First, we note the huge interest in ethanol with more than one-third of the requests in 

both FY 2005 and FY 2006. Second, and even more dramatic, is the increase in biodiesel 

requests from 18% to 29%, which probably reflects the heavy-duty industry’s need to meet the 

stricter emissions requirements of 2007 and the EPAct AFV credits that can be achieved for 

every 450 gallons of biodiesel consumed. Also, CNG interest dropped from 16% in 2005 to only 

9% in 2006, for reasons already noted. 

Appendix VI offers some information on the general types of organizations represented by 

callers to the Hotline. 

 28
Figure 29. Hotline Fuel Type Requests FY05

18%

4%

2% 36%

16%

1%

3%

1%

3%

8%

8% Biodiesel

Biofuels

Ethanol

Methanol

CNG

LNG

Electric

Fuel Cell

Hydrogen

Hybrid

LPG

Figure 30. TRS Requests by Fuel Type FY06

29%

3%

36%

3%

9%

2%

5%

7%

4%

0%

2% Biodiesel

Biofuels

Ethanol

Methanol

CNG

LNG

Electric

Fuel Cell

Hydrogen

Hybrid

LPG

Sources of Requests Received by the Hotline/Technical Response Service 

As expected, when the Hotline was first established, most queries came in via toll-free 800 

phone numbers. Data on the source of the request was not added to the request processing system 

until FY 1997. Even so, in FY 1997, about four-fifths of the requests came in via phone; the rest 

were essentially e-mail requests. In FY 2000, we started differentiating pure e-mail requests from 

 29
those being generated by Web inquiry forms, document searches, etc., on the Internet. Most of 

the “Other” types of requests from FY 1999 to FY 2002 pertained to the handling of FEG 

requests. “Other” types could also be faxes and walk-in requests. One of the most significant 

gleanings from Figure 31 is the continually decreasing proportion of phone inquires with the 

commensurate increase in electronic (e-mail and Web) requests. Electronic requests accounted 

for about one-fifth of all requests in FY 1997, and now represent about two-thirds of all requests 

processed in FY 2006 by the TRS and about half in the last year of the Hotline operation in FY 

2005. This was the desired trend because processing requests electronically is cheaper and more 

efficient. 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

FY97 FY98 FY99 FY00 FY01 FY02 FY03 FY04 FY05 FY06

Figure 31. Sources of Requests Received at the Hotline 

By Fiscal Year (FY97-FY06)

Other

Web

E-Mail

Phone

Hotline Feedback 

The outstanding performance of the Hotline is reflected by direct user feedback. The overall 

positive feedback reflects the service provided by a staff of courteous, friendly, and 

knowledgeable individuals, and the thoroughness of the operators on meeting and exceeding the 

expectations of the users—based on the documentation sent, the answers to questions given, or 

the references to additional sources. With each document request from a caller, a feedback form 

and a postage-free return envelope were included in the package. As feedback forms were 

returned, the discreet answers, often in the form of letter grades, and comments were entered into 

a database for analysis. This database is the source for the graphs that analyze Hotline 

performance and service effectiveness. 

Figure 32 offers a glimpse of how effective the Hotline operators have been over the years. 

Combining all criteria together, 92.6% of all Hotline operator and operations attributes received 

a grade of A; 98.6% received a grade of A or B. Only 0.4% of all grades were D or F, 

demonstrating huge approval ratings for operator courtesy, promptness in answering calls, 

understanding the needs of the callers, and timeliness and efficiency of processing the requests. 

 30
0

500

1,000

1,500

2,000

2,500

3,000

3,500

Feedback Grades.

Courtesy Promptness Unders

Needs

Timeliness Efficiency

Figure 32. Hotline Operator/Operations Feedback 

1996-2005

A

B

C

D,F

Figure 33 asks the question about whether the user needs were met by the staff of courteous, 

prompt, efficient operators. The chart yields an overwhelming “yes” to that answer; 42% of the 

expectations were not only met, but exceeded. In total 97% of the users’ needs were met or 

exceeded, and only 3% of the needs were not met over a 10-year period. When users’ needs were 

not met, usually information in the form of a document or a Web search could not be found to 

provide a responsive answer. 

Figure 33. Were Hotline Expections Met? 

(User Feedback FY96-05)

42%

55%

3%

Exceeded

Met

Did not meet

Another significant question that we asked of users was to evaluate how this Hotline compared 

to other Hotlines they had used. Figure 34 shows overwhelmingly that four of five responders 

said this Hotline was better than other services they used, and only 1% rated it worse than similar 

services. 

 31
Figure 34. Hotline Comparison to Other 

Hotlines (1996-2005) 

79%

20% 1%

Better

Same

Worse

All that is well and good, but what about the documents the users received? Did they satisfy their 

needs? Figure 35 clearly demonstrates high grades for the documents received. They were 

readable, useful, well-organized, and covered the topic well. Combining these four criteria, 71% 

of all documents received a grade of A and 94% received a grade or A or B. Fewer than 1% 

received a failing grade, of 26,927 total grades reported from FY 1996 through FY 2005, when 

the formal publicly accessible Hotline service was discontinued. 

0

1,000

2,000

3,000

4,000

5,000

Feedback Grades.

Readable Usefulness Organization Coverage

Figure 35. Grades on Documents Distributed to Hotline 

Users 1996-2005

A

B

C

D

F

Request Categories 

For each request that was logged by the Hotline, we wanted to know what the request was about. 

Many categories were made available to the Hotline on the request processing form, and the 

following notes and tables help to give a better perspective of what people were asking about 

when they contacted the Hotline. Two tables are provided to see how the requests over time (FY 

 32
1991 to FY 2006) differ from the more recent request types in the past two fiscal years. The 

following chart (Table 1) provides the combined request data for the top 20 request categories 

from FY 1991 to FY 2006. Notes of interest from Table 1 are: 

• These top 20 categories represent about 90% of all classified requests. Requests may also 

be multiply classified, so the 95,194 total request classifications would represent fewer 

total requests than this count reflects. 

• More than one of six requests related to federal and state legislative and regulatory 

activities, tax incentives, the Clean Air Act Amendments, or EPAct. 

• About one in six requests was for information from the AFDC, refueling sites, or OEM 

vehicles. 

• One in eight requests was for FEGs, mostly between FY 1999 and FY 2003. 

• About one of 16 requests was specific to Clean Cities. 

• One in 16 requests was for specific documents. 

• Another 7.5% of requests were related to fuel production, use, or characteristics. 

The shaded categories (Conf/Events, EPAct 1992, and Technology) represent categories that did 

not make top 20 ranking during FY 2005 and FY 2006. EPAct 1992, of course, was old news 

and the Clean Cities conference registrations and related activities became much more automated 

in recent years. 

 Table 1. Top 20 Most Popular Hotline Request Categories (FY 1991-2006) 

Rank Request Type Total % Rank Request Type Total % 

1 Fuel Econ Guide 12,175 12.8% 11 Refueling Sites 3,974 4.2%

2 AFDC 7,868 8.3% 12 Fed Legis/Prog 3,857 4.1%

3 Fuel Related 7,136 7.5% 13 Fund/Grants 3,793 4.0%

4 

AFN/Clean Cities 

Newsletters 6,323 6.6% 14 Indust. Contact 3,690 3.9%

5 Documents 6,306 6.6% 15 OEMs/Auto Mfg 3,020 3.2%

6 Clean Cities Related 6,229 6.5% 16 State Laws/Legis 2,640 2.8%

7 Tax/Incentives 5,798 6.1% 17 Emissions 2,473 2.6%

8 Veh. Conversions 5,075 5.3% 18 Veh. Performance 2,243 2.4%

9 Conf/Events 4,764 5.0% 19 Technology 1,862 2.0%

10 EPAct 1992 4,224 4.4% 20 Mrkt Sply/Dmnd 1,744 1.8%

 Total 95,194 100.0%

Table 2 is provided as a contrast to the full historical request categorizations of Table 1. Again, 

the shaded categories represent those categories that were not in the FY 1991 to FY 2006 chart 

(Table 1). 

 33
 Table 2. Top 20 Most Popular Hotline Request Categories (FY 2005-2006) 

Rank Request Type Total % Rank Request Type Total % 

1 Fuel Related 1,471 15.4% 11 Veh. Performance 367 3.8%

2 Fuel Econ Guide 1,136 11.9% 12 Fund./Grants 306 3.2%

3 AFDC 714 7.5% 13 Documents 305 3.2%

4 OEMs/Auto Mfg 708 7.4% 14 Indust. Contact 283 3.0%

5 Refueling Sites 643 6.7% 15 Mrkt Sply/Dmnd 239 2.5%

6 Fed Legis/Prog 612 6.4% 16 Equipment 200 2.1%

7 Tax/Incentives 594 6.2% 17 Emissions 198 2.1%

8 Veh. Conversions 592 6.2% 18 Infrastructure 155 1.6%

9 AFN/Clean Cities 

Newsletters 423 4.4% 19 

Clean Cities 

Related 135 1.4%

10 State Laws/Legis 389 4.1% 20 Niche Market 111 1.2%

 Total 9,581 100.0%

The notes of significance about these data are: 

• The top 20 categories represent about 90% of all requests, which may be multiply 

classified so the 9,581 total request classifications would represent fewer total requests 

than this count reflects. 

• Compared to the total request history in Table 1, fuel-related requests during FY 2005 

and FY 2006 ranked #1 and doubled in proportion (from 7.5% to 15.4%). 

• More than one in five requests (21.6%) were for information from the AFDC, refueling 

sites, or OEM vehicles, all part of the AFDC information. This is up from the historical 

summary, where only one of six requests related to information in the AFDC. 

• One of seven requests was for information on OEM vehicles or refueling site 

information, ranking these fourth and fifth versus the full historical rankings of 11th and 

15th. 

• About one-sixth of all requests fell in the regulatory/legislative interests of federal 

legislation, tax incentives, and state laws and legislation. 

• With more than one in 10 requests, the FEGs continued to be popular, although most of 

the demand was in FY 2005, before the transfer to the IC. FEG requests fell from #1 

overall to #2 in the FY 2005–2006 requests. 

• Historically, one of 16 requests was specific to Clean Cities (#6 ranking); this dropped 

dramatically in FY 2005 and FY 2006 to 1.2% of requests for a #19 ranking. One major 

factor was the transfer of the Clean Cities Conference to private industry and the lack of 

inquiries surrounding this annual conference. 

• One in 16 requests was for tax incentives, the same for vehicle conversion information. 

Again, the shaded categories (equipment, infrastructure, niche markets) represent categories that 

did not make top the 20 ranking over all time. 

 34
Fleet Managers 

Fleet managers have always been among the top clients in the AFDC with regard to Web 

development and documents created in the DOE/NREL searchable document database. The 

Buyer’s Guide for Fleets morphed into the current, significantly expanded version of the Clean 

Fleet Guide. Many other tools have also been created for use by fleet managers (and others, of 

course). Knowing this, we will take a look at the number of fleet managers who have been added 

to the caller (requester) database and the number of requests they have made since we began to 

gather this information in FY 1995 (Figure 36). Early in the Clean Cities Program, the focus was 

to bring fleet managers into the Clean Cities fold. More than 800 fleet managers were added to 

the caller database; almost 90% of the additions came before 2000. These 804 fleet managers 

have made a total of 1,432 requests of the Hotline, for an average of almost two inquiries per 

fleet manager. With the advent of the Internet, the online tools developed for fleet managers, and 

more managers becoming Web savvy; their need to use the Hotline has diminished since 1998. 

Therefore, the tools and information provided by the Internet, conferences and trade shows, and 

the OEMs seem to be generally satisfying fleet manager’s needs in the world of alternative fuels 

and advanced vehicle technologies. 

0

50

100

150

200

250

300

350

400

450

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006

Figure 36. Fleet Managers AFDC Utilization by FY

Fleet Mngrs Added to AFDC

Fleet Mngrs Requests

 35
Final Remarks 

We have examined a wealth of historical information from the Alternative Fuels Data Center—

information that has not been fully analyzed in the past. We have provided a perspective on the 

growth of the alternative fuels industry since 1991 with regard to OEM vehicle production and 

have described the changing complexion of the industry from the early days of concentrations on 

CNG, alcohol fueled, electric, and LPG vehicles, to today’s hybrids and FFVs. We have 

examined the refueling infrastructure and have shown the chicken-and-egg effect in the CNG 

industry that without sufficient support for vehicle numbers, the continued operation of public 

CNG stations cannot be justified. The Big Three OEMs’ option to concentrate on the FFV 

market was a business decision that answered the question: Which comes first, the vehicles or 

the infrastructure? FFVs allowed the vehicles to arrive and the infrastructure to develop. Hybrids 

skirted this problem and offered an attractive consumer option with no refueling inconvenience. 

L&I from AMFA 1988 to EPAct 1992 and EPAct 2005, among others, have been necessary to 

nurture the growth of activities in the alternative fuels and advanced vehicle technology arenas 

that otherwise would not have occurred without the legislative stimulus and a government/ 

industry cooperative. And we have seen that the Clean Cities Program and the NAFH and Clean 

Cities Hotline have been tremendously successful in acting as the outreach and information 

dissemination organizations so greatly needed to ensure that all of these efforts have an impact 

on the nation’s reduction of our dependence on imported oil. 

 36
Appendices 

Appendix I. Raw Data Used To Generate Some Original Equipment Manufacturer 

Figures by Models Offered and Fuel Type 

Appendix Tables 1 and 2 provide the raw data used to generate Figures 1 to 4. 

Table 1. AFV/HEV Models by OEM & Fuel Type 1991-2006 

Fuel Type Chrysler Ford GMC Honda Toyota Other Total 

CNG 30 62 50 9 3 154 

E85 38 41 40 16 135 

EV 5 10 16 2 9 20 62 

Hybrid 3 4 14 10 31 

LPG 18 3 4 25 

M85 4 8 2 14 

Total 77 142 115 25 22 40 421 

Table 2. AFV/HEV Models by Fuel Type & OEM 1991-2006 

OEM CNG E85 EV Hybrid LPG M85 Total 

Chrysler 30 38 5 4 77 

Ford 62 41 10 3 18 8 142 

GMC 50 40 16 4 3 2 115 

Honda 9 2 14 25 

Toyota 3 9 10 22 

Other 16 20 4 40 

Total 154 135 62 31 25 14 421 

 37
Appendix II. Original Equipment Manufacturer Charts Showing Models Offered by 

Fuel Type over Time 

0

2

4

6

8

10

12

14

16

18

20

1991 1993 1995 1997 1999 2001 2003 2005

Ford MY Offerings By Fuel Type 1991-2006

M85

LPG Ded./Bi-Fuel

Hybrid

EV

Ford Notes

• Only alcohol fuels from 1991 to 1994 (only M85 from 1991 to 1993). 

• CNG vehicles offered for 10 years—1995-2004, plus some LPG vehicles and EVs. 

• Now the only offerings are FFVs and hybrids. 

0

2

4

6

8

10

12

14

16

1991 1993 1995 1997 1999 2001 2003 2005

GM MY Offerings By Fuel Type 1991-2006

M85

LPG Ded./Bi-Fuel

Hybrid

EV

E85

CNG Ded./Bi-Fuel

GM Notes

• GM and Honda were the only OEMs offering CNG LDVs in 2006. 

• FFV offerings dominate GM menu. 

• GM recently entered the hybrid market. 

 38
0

1

2

3

4

5

6

7

8

9

10

1991 1993 1995 1997 1999 2001 2003 2005

DaimlerChrysler MY Offerings By Fuel Type 1991-2006

M85

LPG Ded./Bi-Fuel

Hybrid

EV

E85

CNG Ded./Bi-Fuel

DaimlerChrysler Notes

• DaimlerChrysler was an early player in M85 and CNG, but dropped CNG in 2004. 

• E85 FFVs have been its only AFV offerings for the past three years. 

0

0.5

1

1.5

2

2.5

3

3.5

4

1998 1999 2000 2001 2002 2003 2004 2005 2006

Honda MY Offerings By Fuel Type 1998-2006

LPG Ded./Bi-Fuel

Hybrid

EV

E85

CNG Ded./Bi-Fuel

Honda Notes 

• Honda entered the CNG market in 1998 with its dedicated Civic GX, which it continues 

to offer. 

• It left the EV market in 2000 and now has offerings only in CNG and three hybrid 

models. 

 39
0

0.5

1

1.5

2

2.5

3

3.5

4

1998 1999 2000 2001 2002 2003 2004 2005 2006

Toyota MY Offerings By Fuel Type 1998-2006

LPG Ded./Bi-Fuel

Hybrid

EV

E85

CNG Ded./Bi-Fuel

Toyota Notes

• Toyota entered the EV market in 1998, but has concentrated on the hybrid market since 

2004. 

• On the sales end, since being introduced in 2000, the Toyota Prius has far outperformed 

all other hybrid models combined with more than 500,000 of the estimated 640,000 

HEVs expected to be sold by the end of 2006. 

• The CNG Camry was offered for only three years. 

 40
Appendix III. Laws and Incentives—Supplemental Information 

0

10

20

30

40

50

60

70

80

# of laws/Incentives

CA CT IL IN IA NJ NM NY NC OR TX VA WA

States with >20 Laws and Incentives Related to 

Fuels & Technologies 

Chart Notes

• Not surprisingly, California leads the nation in the numbers of L&I that have been passed 

at the state level with 73, just behind the federal total of 82. 

• Six other states have passed 18 or more L&I, and all other states have at least one L&I 

related to alternative fuel or advanced technologies. 

40

277

8

243

82

812

97

837

0

100

200

300

400

500

600

700

800

900

# of Laws and Incentives.

Incentive Regulation Technology User

Laws and Incentives by Type

Federal

State

Note: Emphasis has been most significant on L&I by fuel/technology and user type. 

 41
Appendix IV. Map of Clean Cities Coalitions 

 42
Appendix V. Supplementary Hotline State and Country Usage Information 209 73 1341 596583 368 61 656873 51 332

0

200

400

600

800

1000

1200

1400

# of Requests

Australia

Brazil

Canada

China

France

Germany

India

Italy

Korea

Mexico

Pakistan

Sweden

UK

Countries with >50 Hotline Requests 1991-2006

Chart Notes 

• These 13 countries with more than 50 requests each represent 73% of all international 

calls (3,885) logged by the Hotline. 

• Canada represents more than one-third of all international requests. 

• Not surprisingly, the four top countries (Canada, the United Kingdom, India, and 

Australia) are predominantly English-speaking nations. 

 43
1

2 3 50 4 24 8 12 6 5

0

2,000

4,000

6,000

8,000

10,000

12,000

# of Requests

CA TX NY DC FL CO MI VA PA IL

Top 10 States (>3,000) Requests 1992-2006

#s on bars refer to 

population rank in 

the US – 2000 

Chart Notes 

• Each of these 10 states had more than 3,000 requests of the NAHF since its inception. 

• Requests from these 10 states total 43,534 through July 2006 and represent almost half of 

all requests to the Hotline. 

• The District of Columbia and Virginia are high because of the proximity to government 

agencies. 

• Colorado is high because of the presence of NREL and the DOE Golden Field Office in 

Golden, and the Federal Center in Lakewood, Colorado. 

• The 10,322 requests from California represent about one in nine of all requests to the 

Hotline. 

 44
Appendix VI. Organization Type of Hotline Users 

These next two charts depict the general organization types of users of the Hotline/TRS services 

from FY 1996 to FY 2006. 

Organization Type of Hotline Users (FY96-06)

8%

9%

8%

8%

34%

2%

2%

29%

Education

Gov-Federal

Gov-State

Gov-Local

Industry

OEMs

International

Private Party

Chart Notes

• One of six Hotline requests was from federal/state government and one-fourth of all 

requests originated from all government types. 

• Another one-third of all requests came from industry and private organizations. 

• One in 12 requests came from education institutions. 

• More that one-fourth stemmed from private individuals. 

 45
Annual Distribution of Hotline Requests By Organization 

Type FY96-FY06

0% 20% 40% 60% 80% 100%

FY96

FY97

FY98

FY99

FY00

FY01

FY02

FY03

FY04

FY05

FY06 Education

Gov-Federal

Gov-State

Gov-Local

Industry

OEMs

International

Private Party

Chart Notes

This chart provides supplementary details on the Hotline requests by organization type over time. 

We can see the general dominance of industry and private individual requests over the 11-year 

period. 

 46
F1147-E(12/2004) 

REPORT DOCUMENTATION PAGE Form Approved 

OMB No. 0704-0188

The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, 

gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this 

collection of information, including suggestions for reducing the burden, to Department of Defense, Executive Services and Communications Directorate (0704-0188). Respondents 

should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a 

currently valid OMB control number. 

PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ORGANIZATION.

1. REPORT DATE (DD-MM-YYYY)

September 2007 

2. REPORT TYPE

Technical Report 

3. DATES COVERED (From - To)

 

5a. CONTRACT NUMBER

DE-AC36-99-GO10337 

5b. GRANT NUMBER

4. TITLE AND SUBTITLE

Historical Perspective of Clean Cities and Alternative Fuels Data 

Center Trends 

5c. PROGRAM ELEMENT NUMBER

5d. PROJECT NUMBER

NREL/TP-540-41069 

5e. TASK NUMBER

FC070023 

6. AUTHOR(S)

J.K. O'Connor 

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)

National Renewable Energy Laboratory 

1617 Cole Blvd. 

Golden, CO 80401-3393 

8. PERFORMING ORGANIZATION 

REPORT NUMBER

NREL/TP-540-41069 

10. SPONSOR/MONITOR'S ACRONYM(S)

NREL 

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)

11. SPONSORING/MONITORING 

AGENCY REPORT NUMBER

12. DISTRIBUTION AVAILABILITY STATEMENT

National Technical Information Service 

U.S. Department of Commerce 

5285 Port Royal Road 

Springfield, VA 22161 

13. SUPPLEMENTARY NOTES

14. ABSTRACT (Maximum 200 Words)

This document draws on the wealth of information housed in the U.S. Department of Energy’s Alternative Fuels Data 

Center at the National Renewable Energy Laboratory. Trends and analyses are examined from data as far back as 

1991. The findings of those trends and salient features are summarized. 

15. SUBJECT TERMS

data mining; afdc; alternative fuels data center; clean cities 

16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON 

a. REPORT 

Unclassified 

b. ABSTRACT 

Unclassified

c. THIS PAGE 

Unclassified

17. LIMITATION 

OF ABSTRACT

UL 

18. NUMBER 

OF PAGES 

19b. TELEPHONE NUMBER (Include area code)

Standard Form 298 (Rev. 8/98) 

Prescribed by ANSI Std. Z39.18