Goals and Accomplishments

Clean Cities coalitions employ three strategies to advance affordable, domestic transportation fuels and technologies:

  • Shift to domestic energy sources, including alternative and renewable fuels, such as natural gas, propane, hydrogen, electricity, ethanol, and biodiesel
  • Improve fuel efficiency using state-of-the-art technologies and strategies
  • Eliminate harmful emissions through idle reduction and other fuel-saving technologies and practices.

Impacts of Alternative Fuels and Advanced Vehicle Technologies

Since 1993, Clean Cities coalitions have steadily increased their energy use impact each year for a cumulative of more than 7.8 billion gasoline gallon equivalents (GGEs). Clean Cities coalitions have helped to place hundreds of thousands of alternative fuel vehicles on the road and establish the fueling infrastructure to serve this growing market. They have also aided in the elimination of millions of hours of vehicle idling and helped accelerate the entry of new transportation technologies into the marketplace.

Cumulative Energy Use Impact

Since 1993, the cumulative energy impact of Clean Cities coalitions has surpassed 7.8 billion GGEs through alternative fuel use, fuel economy improvements, idle-reduction measures, and other strategies. Source: Clean Cities coalitions annual activity reports

Energy Use Impact is a metric that measures combined progress in both reduced energy use (from efficiency improvements) and fuel shifted from petroleum to cleaner domestic alternative fuels. The metric used is gasoline gallon equivalents.

Cumulative Energy Use Impact
Year Annual Cumulative
2016 978000000 7806000000
2015 897000000 6828000000
2014 800000000 5930000000
2013 742000000 5131000000
2012 661000000 4389000000
2011 641000000 3728000000
2010 520000000 3087000000
2009 482000000 2567000000
2008 287000000 2085000000
2007 294000000 1798000000
2006 302000000 1504000000
2005 187000000 1202000000
2004 233000000 1015000000
2003 156000000 782000000
2002 133000000 626000000
2001 119000000 494000000
2000 92000000 375000000
1999 87000000 283000000
1998 67000000 196000000
1997 43000000 128000000
1996 45000000 86000000
1995 26000000 41000000
1994 15000000 15000000

Energy Use Impact by Technology Type

In 2016, Clean Cities coalitions had an energy impact of 837 million gasoline gallon equivalents by using alternative fuel vehicles. Source: Clean Cities coalitions annual activity reports

Energy Use Impact by Technology Type
Technology Type Million GGEs
Natural Gas 475.19
Biodiesel 101.61
HEVs & PEVs 100.32
Ethanol 71.19
Propane 45.50
Fuel Economy 42.84
Idle Reduction 38.89
Renewable Diesel 35.11
VMT Reduction 28.49
Off-Road 16.74
Renewable Natural Gas 7.46

Clean Cities Alternative Fuel Vehicle Inventory


Coalitions have made great strides to integrate alternative fuel vehicles (AFVs) across the United States. In 2016, more than 1.1 million of the AFVs in operation were a result of Clean Cities coalition efforts. Source: Clean Cities coalitions annual activity reports

Clean Cities Alternative Fuel Vehicle Inventory
Fuel 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
Biodiesel 31922 52275 91584 98785 17222 2814 88726 99347 103106 98028 130540 189823 160763
Compressed Natural Gas 76257 49271 57458 55021 51121 44317 42911 48157 59521 79616 68479 107283 98388
Ethanol (E85) 47643 72899 221834 385671 524169 642520 403981 479706 197187 259337 275508 271996 457817
Hybrid Electric 10674 18553 43886 81987 101954 107585 30613 50503 141406 83339 82834 94330 129827
Hydrogen 23 42 72 86 75 74 62 118 50 46 49 95 97
Liquefied Natural Gas 0 1873 2271 1731 2053 2038 3410 4315 3411 3645 2992 3974 4924
Plug-In Electric 9241 7464 9481 5895 14135 4568 9223 10541 20455 32187 65042 96896 171011
Propane 31338 21117 25543 23628 22260 7937 13196 18793 16501 35554 17404 22762 23648
Renewable Diesel 0 0 0 0 0 0 0 0 0 0 0 3183 71066
Renewable Natural Gas 0 0 0 0 0 0 0 0 0 0 313 366 1157

U.S. Alternative Fueling Station Inventory


Today's drivers can find thousands of fueling stations across the country that provide natural gas, electricity, ethanol, and other alternative fuels. Source: Alternative Fuels Data Center

U.S. Alternative Fueling Station Inventory
Fuel Type 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
Biodiesel 0 0 0 0 0 0 0 0 2 16 79 142 176 304 459 742 645 679 644 627 675 757 783 721 697 702 681
Compressed Natural Gas 349 497 1042 1065 1419 1426 1268 1267 1217 1232 1166 1035 917 787 732 721 778 772 841 910 1107 1263 1495 1563 1722 1693 1659
Electric 0 0 0 188 194 310 486 490 558 693 873 830 671 588 465 442 430 465 541 3394 13392 19410 25602 30945 42029 50627 61067
Ethanol (E85) 2 7 32 37 68 71 40 49 113 154 149 188 200 436 762 1208 1644 1928 2142 2442 2553 2639 2840 2990 3091 3322 3617
Hydrogen 0 0 0 0 0 0 0 0 0 0 7 7 9 14 17 32 46 63 58 56 58 53 51 39 54 64 60
Liquefied Natural Gas 0 0 0 0 72 71 66 46 44 44 36 62 58 40 37 35 38 36 39 45 59 81 103 111 140 131 137
Methanol (M85) 43 50 82 88 95 106 91 51 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Propane 3297 3297 3299 3299 4252 4255 5318 4153 3268 3403 3431 3966 3689 2995 2619 2371 2175 2468 2647 2597 2654 2956 2931 3594 3665 3514 3341


Since 1993, the U.S. Department of Energy (DOE) has funded nearly 600 transportation projects nationwide through a competitive application process and has distributed close to $400 million in project awards. These funds have leveraged nearly $800 million in additional matching funds and in-kind contributions from the public and private sectors.

National Award Recipients

DOE recognizes the accomplishments of Clean Cities coalitions and stakeholders through the Hall of Fame.