Climate: Secretary Buttigieg & USDOT’s Accomplishments
(February 2021–January 2025)
This is Part V of a series on Secretary Pete Buttigieg and USDOT’s Accomplishments (February 2021 to January 2025). This part describes the Secretary and USDOT’s efforts to cut greenhouse gas pollution — also referred to as carbon emissions — generated by transportation systems. Cutting this pollution was a high priority for the Secretary, because carbon emissions accumulate in the atmosphere, trapping more and more heat and causing the Earth’s climate to grow warmer and warmer over time.
Note that some important segments of Secretary Buttigieg and USDOT’s climate work are covered in other sections. For work to reduce vehicle emissions by expanding alternative transportation options, see Accomplishment #13 on “Transportation Options.” For work on climate resilience, see Accomplishment #15 on “Resilience.”
To navigate to other parts of this series, follow these links: [These links will be added over time as each part gets published.]
- Main Article (coming soon)
- Part I: Legislation & Implementation
- Part II: Safety
- Part III: Economic Competitiveness
- Part IV: Equity
- Part V: Climate
- Part VI: Innovation (coming soon)
Note that this series only covers Secretary Buttigieg’s tenure and does not discuss policy changes or developments that occurred after he left office.
Abbreviations
- IIJA — Infrastructure Investment and Jobs Act (aka, Bipartisan Infrastructure Law), which covers the five-year period of FY 2022–2026
- USDOT — US Department of Transportation
- FAA — Federal Aviation Administration
- FHWA — Federal Highway Administration
- FMCSA — Federal Motor Carrier Safety Administration
- FRA — Federal Railroad Administration
- FTA — Federal Transit Administration
- GLS — Great Lakes St. Lawrence Seaway Development Corporation
- MARAD — Maritime Administration
- NHTSA — National Highway Traffic Safety Administration
- OIG — Office of the Inspector General
- OST — Office of the Secretary of Transportation (For simplicity, this article refers to OST as USDOT)
- PHMSA — Pipeline and Hazardous Materials Safety Administration
Table of Contents
Click on the links in this section to navigate this article.
[Note: Some important segments of Secretary Buttigieg and USDOT’s climate work are covered in other sections. For work to reduce vehicle emissions by expanding alternative transportation options, see Accomplishment #13 on “Transportation Options.” For work on climate resilience, see Accomplishment #15 on “Resilience.”]
20. Cleaner vehicles, aircraft, ships, and trains: Increased fuel economy standards for passenger cars, light trucks, heavy-duty pickup trucks, and vans to save roughly 270 billion gallons of gasoline and prevent about 3.2 billion metric tons of carbon emissions through 2050. Implemented federal policies to improve US drivers’ access to electric vehicles (EVs) and charging infrastructure, helping to more than triple the number of registered light-duty EVs on US roads and double public EV charging ports during Secretary Buttigieg’s tenure. Required interoperability for federally-funded EV chargers, spurring Tesla to open up 7,500 of its chargers by the end of 2024. Created the National Electric Vehicle Infrastructure (NEVI) program, which reimbursed state governments for constructing fast-charging stations (aka, Level 3 or DC fast chargers) along major highway corridors. By the end of the Secretary’s tenure, 13 states had used the NEVI program to construct 50 charging stations with 217 fast-charging ports, funded with $27.6 million; and 32 states, DC, and Puerto Rico were in the process of developing another 903 charging stations with at least 3,612 fast-charging ports under the NEVI program, conditionally awarding $469.4 million to construct these stations. Funded the repair or replacement of nearly 4,500 charging ports. Created the Charging and Fueling Infrastructure (CFI) program and awarded over $1.7 billion in CFI grants to fund over 28,000 new EV charging ports in communities across the country. USDOT more than quadrupled the number of zero-emission vehicles in its fleet, from 159 zero-emission vehicles in FY 2021 to 758 zero-emission vehicles in FY 2024. Funded more than 3,500 low- and zero-emission American-made transit buses, expected to more than double the number of zero-emission buses on US roads. Awarded $291 million to 36 projects that expand supplies of sustainable aviation fuel or develop or demonstrate low-emission aviation technologies. Awarded over $146 million for electric or low-emission ferry systems. Funded the replacement of 97 locomotives with cleaner locomotives that cut emissions, including 34 new battery-electric locomotives. Conducted a feasibility study on low-carbon alternative fuels for shipping on the Great Lakes.
- Corporate Average Fuel Economy (CAFE) standards
- Electric vehicles (EVs), EV chargers, and alternative-fueling infrastructure
- Low or no-emission buses
- Sustainable aviation fuel (SAF) and lower-emission aircraft
- Electric or low-emitting ferries
- Rail decarbonization
- Green maritime shipping
21. Investment decisions and operations to cut carbon emissions: Launched the $6.4 billion Carbon Reduction Program that gives states flexibility to pursue a wide range of emission-cutting strategies. Awarded $1.2 billion to projects that use American-made construction materials that have substantially lower lifecycle carbon emissions than typical materials. Adopted USDOT’s first-ever department-wide Buy Clean policy to prioritize low-carbon construction materials in federal procurement. Awarded $148 million to projects that reduce truck emissions at ports. Awarded nearly $200 million to port infrastructure projects that support offshore wind development. Made offshore wind vessels eligible for federal financial support through the Title XI Federal Ship Financing Program, promoting shipbuilding of vessels that construct and maintain offshore wind facilities. Optimized the descent path of aircraft to save millions of gallons of jet fuel per year at 53 airports. Finished testing NASA software that will efficiently manage air traffic and avoid over 75,000 tons of emissions each year. Selected a sustainable design for new air traffic control towers that will replace older towers at municipal and smaller airports.
- Carbon Reduction Program
- Low-carbon construction materials
- Cutting emissions at US ports
- Offshore wind
- Sustainable aviation operations and facilities
Climate
In April 2021, President Biden set a national goal to reduce US greenhouse gas emissions by 50% by 2030 (relative to 2005 levels) and reach net-zero emissions by 2050. Transportation produced more carbon emissions than any other sector of the economy, so Secretary Buttigieg prioritized bringing down these emissions in line with the President’s goal (Chart V.1).
In April 2021, Secretary Buttigieg re-established USDOT’s Climate Change Center and appointed Dr. Robert Hampshire to serve as USDOT’s first Chief Science Officer in decades. “The re-introduction of a Chief Science Officer underscores transportation’s key role in addressing the complexity and criticality of our dynamically changing climate… It is important that USDOT incorporate scientific research to advance climate change initiatives that are fair and equitable to all,” said Dr. Hampshire, who also served as USDOT’s Deputy Assistant Secretary for Research and Technology.
In January 2023, the US National Blueprint for Transportation Decarbonization was published by the US Department of Energy, USDOT, the Environmental Protection Agency, and the US Department of Housing and Urban Development. There were three key strategies outlined in the blueprint:
- Increase convenience by supporting community design and land-use planning so people can live near jobs and services, which reduces commutes and improves walkability, bike-ability, and quality of life.
- Improve efficiency by expanding affordable, accessible, efficient, and reliable options like public transportation and rail, and improve the efficiency of all vehicles.
- Transition to clean options by deploying zero-emission vehicles and fuels for transportation.
Secretary Buttigieg gave a helpful overview of these three strategies at a SXSW town hall in March 2022 (Video V.1).
The “Transportation options” section already touched on strategies to promote transit-oriented development, public transit, walking, biking, passenger rail, etc. And the “Resilience” section already discussed USDOT’s programs to help communities prepare for the impacts of climate change.
So this section will focus on the Secretary and USDOT’s initiatives to:
- Promote zero-emission and lower-emission vehicles, aircraft, ships, and trains; and
- Integrate climate action into investment decisions and operations.
By the end of Secretary Buttigieg’s time in office, there were signs that these initiatives were helping to curb the rise in emissions as the economy recovered from the effects of COVID. US energy-related transportation emissions stayed below pre-COVID levels, even as vehicles returned to the roads and airline passengers returned to the skies (Chart V.2).
20. Cleaner vehicles, aircraft, ships, and trains
Summary: Increased fuel economy standards for passenger cars, light trucks, heavy-duty pickup trucks, and vans to save roughly 270 billion gallons of gasoline and prevent about 3.2 billion metric tons of carbon emissions through 2050. Implemented federal policies to improve US drivers’ access to electric vehicles (EVs) and charging infrastructure, helping to more than triple the number of registered light-duty EVs on US roads and double public EV charging ports during Secretary Buttigieg’s tenure. Required interoperability for federally-funded EV chargers, spurring Tesla to open up 7,500 of its chargers by the end of 2024. Created the National Electric Vehicle Infrastructure (NEVI) program, which reimbursed state governments for constructing fast-charging stations (aka, Level 3 or DC fast chargers) along major highway corridors. By the end of the Secretary’s tenure, 13 states had used the NEVI program to construct 50 charging stations with 217 fast-charging ports, funded with $27.6 million; and 32 states, DC, and Puerto Rico were in the process of developing another 903 charging stations with at least 3,612 fast-charging ports under the NEVI program, conditionally awarding $469.4 million to construct these stations. Funded the repair or replacement of nearly 4,500 charging ports. Created the Charging and Fueling Infrastructure (CFI) program and awarded over $1.7 billion in CFI grants to fund over 28,000 new EV charging ports in communities across the country. USDOT more than quadrupled the number of zero-emission vehicles in its fleet, from 159 zero-emission vehicles in FY 2021 to 758 zero-emission vehicles in FY 2024. Funded more than 3,500 low- and zero-emission American-made transit buses, expected to more than double the number of zero-emission buses on US roads. Awarded $291 million to 36 projects that expand supplies of sustainable aviation fuel or develop or demonstrate low-emission aviation technologies. Awarded over $146 million for electric or low-emission ferry systems. Funded the replacement of 97 locomotives with cleaner locomotives that cut emissions, including 34 new battery-electric locomotives. Conducted a feasibility study on low-carbon alternative fuels for shipping on the Great Lakes.
Corporate Average Fuel Economy (CAFE) standards
Established in the 1970s, Corporate Average Fuel Economy (CAFE) standards are federal regulations on the average fuel economy (miles per gallon) of passenger cars and light trucks across an automobile manufacturer’s entire fleet. There are also separate CAFE standards for medium- and heavy-duty trucks and engines. If an automaker’s fleet is more fuel efficient than the standard, it earns CAFE credits. If an automaker fails to meet the standard, it must use CAFE credits that it saved from previous years, buy CAFE credits from other automakers, or pay a penalty.
In 2012, the Obama administration finalized a rule to raise NHTSA’s CAFE standards by an average of 5% annually through model year 2025. In 2020, the Trump administration quickly moved to roll back these standards to increase by an average of just 1.5% annually through model year 2026.
In April 2022, Secretary Buttigieg and NHTSA announced that CAFE standards would be ratcheted back up by 8% annually for model years 2023–2025 and 10% annually for model year 2026. The new standard required an average of 49 miles per gallon by 2026, so Americans purchasing new vehicles in 2026 would get 33% more miles per gallon as compared to 2021 vehicles. NHTSA estimated that this would reduce fuel use by more than 200 billion gallons and carbon emissions by 2.5 billion metric tons through 2050.
In June 2024, Secretary Buttigieg and NHTSA announced that CAFE standards would increase by 2% per year for model years 2027–2031 for passenger cars, while light trucks would increase 2% per year for model years 2029–2031. These increases would bring the average light-duty vehicle fuel economy up to 50.4 miles per gallon by model year 2031, saving passenger car and light truck owners more than $600 in fuel over the lifetime of their vehicles. Heavy-duty pickup truck and van fuel efficiency was set to increase 10% per year for model years 2030–2032 and 8% per year for model years 2033–2035. This would result in a fleetwide average of about 35 miles per gallon by model year 2035, saving heavy-duty pickup and van owners more than $700 in fuel over the lifetime of their vehicles. The new standards announced in June 2024 were projected to save nearly 70 billion gallons of gasoline through 2050 and prevent over 710 million metric tons of carbon emissions by 2050.
NHTSA also tightened enforcement of CAFE standards. In March 2022, NHTSA finalized a rule that more than doubled the penalty for automakers whose vehicles fail to meet the standard for model year 2019 and beyond. For the 2019 to 2021 model years, the fine was $14, up from $5.50, for every 0.1 mile per gallon new vehicles fell short of the standard, multiplied by the number of noncompliant vehicles sold. For the 2022 model year, the penalty was increased to $15.
In July 2024, following an investigation, General Motors was required to pay a $145.8 million penalty and cancel more than 30.6 million CAFE credits for failing to meet CAFE standards for the 2008–2010 model years.
Electric vehicles (EVs), EV chargers, and alternative-fueling infrastructure
On average in the United States, driving a battery electric vehicle generates about 80% less carbon emissions than driving a comparable gas vehicle per year, according to data from the Energy Information Administration in 2024 (Chart 20.1). And when accounting for the total emissions over the life-cycle of the vehicle — including manufacturing the battery and the vehicle and producing energy to operate the vehicle — a medium-size battery electric vehicle in the US produces 64% less carbon emissions, on average, than a comparable gas vehicle, according to the International Energy Agency in 2024 (Image 20.1). The exact emissions savings of each particular EV depends on many factors (e.g., the fuel mix used to generate the electricity, the number of miles driven during the life of the vehicle, etc.), but in general, switching from a gas vehicle to an EV significantly cuts emissions. For this reason, as well as economic competitiveness reasons, Secretary Buttigieg and the Biden administration supported the adoption of EVs in the US and the growth of the American EV industry.
Over the years that Secretary Buttigieg served in office, the number of registered light-duty electric vehicles (EVs) in the United States more than tripled, reaching 5.8 million EVs on the road in 2024 — up from 1.6 million in 2020 (Chart 20.2). This enormous growth was encouraged by policies enacted under the Biden administration — such as new federal tax credits for new and used EVs created by the Inflation Reduction Act of 2022, federal investments in domestic battery production and EV manufacturing, stronger vehicle fuel economy and emissions standards for vehicles, and federal procurement of EVs. In FY 2021, USDOT had 159 zero-emission vehicles in its fleet. By FY 2024, this increased to 758 zero-emission vehicles in USDOT’s fleet of 4,643 light-duty vehicles.
This growth in EV adoption also depended on growth in EV charging infrastructure. President Biden set a goal for the US to have 500,000 public EV charging ports by 2030. Between January 2021 and January 2025, the US made strong progress toward the President’s goal, doubling the number of public EV charging ports and reaching over 200,000 public EV charging ports by the time Secretary Buttigieg left office (Chart 20.3).
USDOT and the US Department of Energy collaborated on initiatives to expand EV charging networks. To facilitate this collaboration, the IIJA established the Joint Office of Energy and Transportation (Joint Office), which Secretary Buttigieg and Secretary Jennifer Granholm officially launched in December 2021 (Image 20.2).
The IIJA created two programs dedicated to expanding and strengthening America’s EV charging and alternative fueling network:
- The National Electric Vehicle Infrastructure (NEVI) Formula Program
- The Charging and Fueling Infrastructure (CFI) Grant Program
These programs will be explained in more detail below.
(1) The National Electric Vehicle Infrastructure (NEVI) Formula Program
The NEVI program was created to fill in gaps in America’s EV fast-charging network across all 50 states, the District of Columbia, and Puerto Rico, ensuring that a fast-charging station (aka, Level 3 charger or DC fast charger) is located every 50 miles along 75,000 miles of major highway corridors. The IIJA authorized a total of $5 billion for this program over a five-year period, with the funds allocated to each state via a formula set by Congress. During Secretary Buttigieg’s tenure, $2.4 billion in NEVI funding was made available to state governments (Image 20.5). Under the NEVI program, state governments (not USDOT) were responsible for overseeing and managing the construction of charging stations, and they could apply to FHWA to reimburse 80% of eligible project costs.
To be eligible for funding, these chargers needed to be located within EV Alternative Fuel Corridors — which were designated by FHWA based on nominations from state and local officials (Image 20.3).
Secretary Buttigieg has also sought to link these EV Alternative Fuel Corridors with the EV charging networks of neighboring countries. In May 2023, the Secretary joined Canadian Minister of Transport Omar Alghabra and Governor Gretchen Whitmer (D-MI) to announce the first Binational EV Corridor between Kalamazoo, Michigan and Quebec City, with NEVI-funded fast chargers on the US side.
To participate in the NEVI program, states had to develop and submit a State EV Infrastructure Deployment Plan to the Joint Office for FHWA approval. If a state did not submit an acceptable plan (or if it failed to implement its plan), its NEVI funding would get redistributed on a competitive basis to local governments within the state to construct eligible EV chargers. In September 2022, Secretary Buttigieg announced that all 50 states, the District of Columbia, and Puerto Rico had submitted plans that were all approved by FHWA.
In February 2023, FHWA issued a final rule establishing minimum standards and requirements for projects funded under the NEVI program. This rule was designed to ensure that NEVI-funded charging stations meet high quality standards for speed and reliability, are properly installed and maintained, have transparent pricing, and are easy to use with a credit card or debit card without needing to download an app or have a membership. Significantly, this rule also stipulated that EV chargers must comply with interoperability standards. This requirement had an immediate impact on the EV industry. To qualify for NEVI funding, Tesla agreed to open 7,500 chargers from its Supercharger and Destination Charger network to non-Tesla EVs by the end of 2024. By the end of February 2023, the company had already begun opening some of its Supercharger stations.
Seeking to leverage NEVI funding, in July 2023, a group of international automakers — BMW, General Motors, Honda, Hyundai, Kia, Mercedes-Benz, and Stellantis — announced a joint venture to install at least 30,000 EV fast chargers along US and Canadian highways and in cities by 2030, with the first chargers opening during the summer of 2024. The automakers said that these chargers would be powered by renewable energy.
To remove barriers to constructing EV charging stations, in September 2023, USDOT used newly-enacted authority to adopt the US Department of Energy’s Categorical Exclusion for EV Charging Stations. This allowed EV charging stations to be permitted without requiring an environmental impact statement or an environmental assessment, which would unnecessarily slow the process. In March 2024, FHWA also issued a request for information to improve and update its standards for EV charging.
In December 2023, Ohio opened the first EV fast-charging station funded through the NEVI program — the first of 27 stations that Ohio planned to deploy (Image 20.4). The states of New York and Pennsylvania soon followed with completed NEVI-funded charging stations.
EV States Clearinghouse created a helpful dashboard to track the progress of states’ implementation of the NEVI program. This section will refer to data and screenshots gathered from the dashboard on January 22, 2025, just two days after Secretary Buttigieg left office.
According to the EV States Clearinghouse dashboard (as reported on January 22, 2025), 43 states/territories had issued at least one solicitation to begin selecting contractors to construct NEVI-funded charging stations, and 37 states/territories had awarded a total of $510 million to construct roughly 3,000 fast-charging ports (Image 20.5). The average funding per charging port was $140,500.
As of January 22, 2025, the dashboard reported that 13 states had completed at least one operational NEVI-funded charging station: Colorado, Hawaii, Kentucky, Maine, Michigan, New York, Ohio, Pennsylvania, Rhode Island, Texas, Utah, Vermont, and Wisconsin (Image 20.6). Under the NEVI program, these states awarded $27.6 million to complete 50 charging stations with 217 fast-charging ports, which were open for public use when Secretary Buttigieg left office (Image 20.7).
The dashboard also reported that 32 states, the District of Columbia, and Puerto Rico had conditionally awarded $469.4 million to construct another 903 charging stations through the NEVI program (Image 20.7). The NEVI program required that at least four fast-charging ports must be constructed at each charging station, so this means that states/territories had conditionally awarded funding to construct at least another 3,612 fast-charging ports as of January 22, 2025.
The IIJA also required that 10% of NEVI funding be set aside for FHWA to support states and localities that need additional assistance to deploy EV charging infrastructure. For the first round of these grants, FHWA focused on improving the reliability of the current charging network. In January 2024, Secretary Buttigieg and FHWA awarded nearly $150 million across 20 states to repair or replace nearly 4,500 existing EV charging ports so they can return to operation (Image 20.8). For example, the City of Blue Earth, MN was awarded $48,533 to upgrade two fast-charging ports that were non-operational, and these upgraded charging ports were opened for public use in October 2024.
In January 2025, the second round of set-aside NEVI grants were awarded together with Charging and Fueling Infrastructure (CFI) grants. These will be discussed further below.
Especially among right-wing social media influencers, much misinformation was spread about the NEVI program during Secretary Buttigieg’s time in office. There was a frequent false claim that the Secretary “spent $7.5 billion on eight EV charging stations.” In reality, under the NEVI program between February 2023 (when the NEVI standards were finalized) and January 2025 (when Secretary Buttigieg left office):
- 13 states completed the construction of 50 charging stations with 217 fast-charging ports, funded with $27.6 million.
- In 32 states, the District of Columbia, and Puerto Rico, another 903 charging stations with at least 3,612 fast-charging ports were in the process of being developed and constructed, conditionally awarded $469.4 million.
- The average funding per fast-charging port was $140,500.
- FHWA reimburses states for 80% of eligible project costs through the NEVI program. So if states do not build charging stations, then they do not receive NEVI funds. Any unspent NEVI funds remain in the US Treasury.
(2) The Charging and Fueling Infrastructure (CFI) Grant Program
The CFI Program was created to invest in EV charging and hydrogen fueling infrastructure at community locations — like schools, parks, libraries, multi-family housing, etc. — as well as along highways in Alternative Fuel Corridors. Under the IIJA, the CFI program was authorized $2.5 billion over five years.
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During Secretary Buttigieg’s time in office, he and FHWA awarded CFI grants in three sets of announcements:
- In January 2024, $623 million in CFI grants were awarded to EV charging and alternative fueling infrastructure across 22 states, two Tribes, and Puerto Rico, funding the addition of about 7,500 new EV charging ports. These grants included $311 million to 36 community projects that expand EV charging infrastructure within communities across the country and $312 million to 11 corridor projects that were located along roadways designated as Alternative Fuel Corridors.
- In August 2024, $521 million in CFI grants were awarded to EV charging and alternative fueling infrastructure across 29 states, eight Tribes, and the District of Columbia, funding the addition of over 9,200 new EV charging ports. These grants included $321 million to 41 community projects and $200 million to 10 corridor projects.
- In January 2025, $635 million in CFI grants were awarded to EV charging and alternative fueling infrastructure across 27 states, four Tribes, and the District of Columbia, funding the addition of over 11,500 new EV charging ports. These grants included $368 million to 42 community projects and $268 million to seven corridor projects.
Examples of projects that received CFI grants in the January 2024 round:
- The Mount Vernon Library Commons project in Washington state was awarded a $12.5 million CFI grant to install over 70 EV charging ports in a public parking garage located in a historic downtown area by the Skagit River and I-5, an Alternative Fuel Corridor (Image 20.9). The project was also designed to have capacity to install another 200 charging ports in the future, creating what could be the largest regional EV charging hub in the nation. On September 28, 2024, the Mount Vernon Library Commons was completed and opened 76 EV charging ports funded by the CFI grant.
- Cochise County, AZ was awarded a $500,000 CFI grant to add seven EV chargers (six dual-port Level 2 chargers and one DC fast charger) in Sierra Vista, Bisbee, and Wilcox, located near major highways or near public transport stops. These charging stations were completed and open for public use in June 2025 (Video 20.1).
- Deerfield, MA was awarded a $2.46 million CFI grant to install the region’s first DC fast chargers (four ports) as well as four Level 2 charging ports at the Leary Public Parking Lot. These charging ports were completed and open for public use in November 2024 (Image 20.10).
- The San Joaquin Valley Unified Air Pollution Control District was awarded a $56 million CFI grant to construct two truck charging sites along the I-5 corridor in Taft, CA (Kern County) and Gustine, CA (Merced County). These two sites were designed to include 90 DC fast chargers for passenger vehicles, 85 DC fast chargers for medium and heavy duty electric vehicles, and 17 megawatt charging standard chargers. The sites also planned to enhance grid stability with 63 acres of solar panels and battery electric storage systems. These sites were under development by WattEV when Secretary Buttigieg left office.
Low or no-emission buses
Between 2021 and 2023, annual funding for FTA’s Low or No-Emission Bus Program increased by more than six-fold thanks to the IIJA. This program provides competitive grants to transit agencies to purchase or lease zero-emission and low-emission transit buses, including the acquisition, construction, or leasing of facilities to support these buses. Under the IIJA, 5% of the program’s funding must go toward training transit workers on how to operate and maintain these buses.
Secretary Buttigieg and FTA awarded three rounds of grants from the Low or No-Emission Bus Program and the Buses and Bus Facilities Program funded by the IIJA:
- In August 2022, $1.66 billion was awarded to fund over 1,800 new buses, with over 1,100 of these buses using zero-emissions technology. (Of this total, $1.1 billion was awarded from the Low or No-Emission Bus Program.) This round of funding alone was expected to nearly double the number of no-emission transit buses on US roadways.
- In June 2023, nearly $1.7 billion was awarded to fund over 1,700 buses, nearly half of which were zero-emission models. (Of this total, $1.2 billion was awarded from the Low or No-Emission Bus Program.)
- In July 2024, about $1.5 billion was awarded to fund new American-made buses in 117 communities across 47 states. (Of this total, $1.1 billion was awarded from the Low or No-Emission Bus Program.) About 80% of these buses use zero or low emission technology.
Some examples: In 2023, the city of Seattle, WA was awarded $33.5 million to buy about 30 battery electric buses, install charging equipment, and train workers to maintain the electric fleet. The city of Hattiesburg, MS was awarded over $6.4 million to replace diesel buses with battery electric buses, purchase charging equipment, and develop a workforce training program. In 2022, the city of Las Cruces, NM was awarded over $5.7 million to replace aging diesel buses with battery electric buses, purchase electric chargers, and create jobs, reducing carbon emissions by an estimated 887 metric tons per year. The city of Davenport, IA was awarded nearly $4.9 million to buy battery electric buses and charging equipment to replace older diesel vehicles that had reached the end of their useful life. In December 2025, Davenport celebrated the addition of four battery electric buses to its fleet, estimating that these buses would save between $11,000 and $43,000 per year in operating and maintenance costs compared to diesel buses.
In total during Secretary Buttigieg’s tenure, FTA funded more than 3,500 low- and zero-emission American-made transit buses.
Sustainable aviation fuel (SAF) and lower-emission aircraft
Sustainable aviation fuel (SAF) is made from renewable biomass and waste resources, and it was a key part of the Biden administration’s strategy to reduce greenhouse gas emissions from the aviation sector.
In December 2021, Secretary Buttigieg and the FAA awarded over $1.4 million to five universities to identify regional feedstock for SAF production using the region’s existing infrastructure to create a dependable SAF supply chain within reach of airports.
In September 2022, USDOT, the US Department of Energy, the US Department of Agriculture, and other federal agencies released the SAF Grand Challenge Roadmap, which outlines a strategy to produce 3 billion gallons of SAF per year by 2030 — compared to an estimated 26.3 million gallons in 2023 — and continue increasing SAF production to 35 billion gallons per year by 2050 to fully meet US aviation fuel demand. The Grand Challenge requires that SAF must have at least 50% lower lifecycle emissions than jet fuel. Achieving these goals would reduce US aviation emissions by 20% by 2030.
“Aviation is difficult to decarbonize because of the need for an energy-dense liquid fuel to power an aircraft that will carry several hundred passengers and cargo thousands of miles at high speeds in a vehicle that can weigh several hundred tons. To understand the energy needs of aviation, it helps to consider that at takeoff, the jet engines of a Boeing 777 wide-body jet are generating power levels comparable to a small nuclear reactor (e.g., 130 MW). Energy sources other than liquid hydrocarbon jet fuels, such as battery technologies and hydrogen, will thus be limited in the near and medium term to small aircraft flying short ranges and are not expected to contribute to substantially reducing aviation emissions until after 2050. This makes widescale production and use of SAF the highest impact near-term strategy for significantly reducing aviation emissions and achieving the nation’s net zero emissions goals for aviation by 2050.”
SAF Grand Challenge Roadmap (September 2022)
To support the Biden administration’s SAF goals, the Inflation Reduction Act of 2022 established new Fueling Aviation’s Sustainable Transition (FAST) grants, which fund two types of projects:
- FAST-SAF grants help to develop SAF infrastructure projects and build up SAF supply chains.
- FAST-Tech grants accelerate the development and demonstration of aviation technologies that reduce greenhouse gas emissions, improve aircraft fuel efficiency, and increase SAF usage.
In August 2024, Secretary Buttigieg and the FAA awarded $291 million in FAST grants, which included:
- $244.5 million in FAST-SAF grants for 22 projects that produce, blend, or store SAF. For example, $16.8 million was awarded to Gevo, Inc. to convert an existing fuel facility in Luverne, MN to a fully integrated alcohol-to-jet production facility for SAF production.
- $46.5 million in FAST-Tech grants for 14 projects that develop, demonstrate, or apply low-emission aviation technologies. For example, $8 million was awarded to JetZero, Inc. to develop technologies for a highly fuel-efficient blended-wing-body airplane, conducting this work in Long Beach, CA; Wichita, KS; and Starkville, MS.
As of April 2024, the FAA reported that more than 450,000 flights had been flown using a combination of SAF and traditional jet fuels. And during the latter half of 2024, SAF production capacity expanded rapidly in the US (Chart 20.4). In early 2024, SAF production capacity was only 2,000 barrels per day, but this increased by about 25,000 barrels per day by the end of 2024. This was the result of Phillips 66 completing its 10,000-barrels-per-day SAF project in Rodeo, CA and Diamond Green Diesel completing its 15,000-barrels-per-day SAF project in Port Arthur, TX.
The FAA also promoted the development of more fuel efficient and lower-emission aircraft and engine technologies through its Continuous Lower Energy, Emissions and Noise (CLEEN) Program. This program was designed to be implemented in five phases, with each phase spanning five years. The first phase started in 2010, and several of the technologies that were tested during that five-year period have since been successfully integrated into new aircraft that currently operate today. In September 2021, Secretary Buttigieg and the FAA awarded over $100 million to six industry partners for the third phase of the CLEEN Program. The third phase aimed to improve aircraft fuel efficiency by at least 20% relative to the International Civil Aviation Organization standard. For example, using this CLEEN Program grant, General Electric Aviation was awarded funding to develop an advanced engine propulsion system to reduce fuel consumption, electric and hybrid-electric systems to increase fuel efficiency, and advanced combustion and thermal management systems to reduce emissions and fuel consumption.
Electric or low-emitting ferries
The IIJA allocated $250 million over five years to FTA’s brand new Electric or Low-Emitting Ferry Pilot Program.
In January 2023, Secretary Buttigieg and FTA awarded $97.6 million to seven projects in seven states through this new program. For example, Washington state received $4.9 million to build an electric charging facility at the Clinton Ferry Terminal, as part of plans to electrify the Mukilteo-Clinton Ferry Route (Image 20.12).
In September 2024, Secretary Buttigieg and FTA awarded another round of $49 million to six projects in five states. For example, the San Francisco Bay Area Water Emergency Transportation Authority was awarded $11.5 million to build two new electric ferry vessels.
Rail decarbonization
Secretary Buttigieg and FRA invested in battery electric locomotives and lower-emission locomotives through the Consolidated Rail Infrastructure and Safety Improvements (CRISI) locomotive replacement initiative (LRI). In CRISI grants announced in September 2023, the LRI supported the replacement of 39 locomotives to meet more stringent emissions standards, including 15 new battery-electric locomotives. To give some examples of these projects:
- The Maryland DOT was awarded $11.5 million to bring the first-ever zero-exhaust emissions locomotives to an East Coast port, replacing three older locomotives with new battery electric locomotives and constructing a battery charger at the Port of Baltimore.
- The Kansas DOT was awarded $15.7 million to convert eight non-regulated or Tier 0 locomotives into fully battery powered units, which will be deployed across Watco’s short line railroads.
- The South Carolina Department of Commerce was awarded nearly $4.2 million to procure two zero-emission lithium battery electric locomotives and install the associated charging technology.
In CRISI grants announced in October 2024, the LRI supported the replacement of 58 locomotives to meet more stringent emissions standards, including 19 zero-emission locomotives. To give some examples of these projects:
- The California Air Resources Board was awarded $36.5 million to replace 10 diesel locomotives with nine zero-emission battery electric locomotives and one hydrogen fuel cell locomotive. This grant also funded four battery chargers.
- Watco Companies, LLC was awarded $19.8 million to replace eight diesel locomotives with eight zero-emission battery electric locomotives, which will be used at five Watco facilities in Montana, Oregon, Tennessee, Texas, and Washington state.
- GCR Acquisitions LLC was awarded nearly $3.4 million to rehabilitate an older diesel locomotive to a zero-emission battery electric locomotive to operate on the Class III Grand Canyon Railway’s tourist operation between Williams, AZ and the South Rim of the Grand Canyon National Park.
CRISI applicants must submit data on the estimated emission reduction of their proposed projects. To help applicants produce these estimates in a standardized and easy-to-use way, in November 2024, USDOT’s Volpe Center developed a Locomotive Emissions Comparison Tool.
In December 2023, the Secretary and FRA also awarded $6.1 billion to two all-electric high-speed rail projects.
In May 2023, FRA hosted an international workshop on rail decarbonization in Denver, CO. The event featured presentations from key federal agencies, international experts from six countries, and US stakeholders from Amtrak, the American Public Transportation Association (APTA), the Association of American Railroads (AAR), BNSF Railway, Caltrans, and more.
In December 2023, Secretary Buttigieg joined Energy Secretary Jennifer Granholm and Canada’s Minister of Transport Pablo Rodriguez to announce the creation of a binational Rail Decarbonization Task Force, which had three objectives: 1) Establish a joint research agenda to test the safe integration of emerging technologies, including hydrogen-powered and battery electric locomotives; 2) Coordinate strategies to accelerate the transition from diesel-powered locomotives to zero-emission technologies, in line with a net-zero emissions goal by 2050; and 3) Collaborate on the development of a US-Canada rail sector net-zero climate model by 2025.
In December 2024, USDOT, the US Department of Energy, EPA, and HUD published “An Action Plan for Rail Energy and Emissions Innovation.” The plan explored seven strategies to decarbonize the rail sector.
Green maritime shipping
During Secretary Buttigieg’s tenure, USDOT began studying the decarbonization of maritime shipping fleets. In September 2022, MARAD launched a study to explore low-carbon options for shipping on the Great Lakes. In March 2024, the study was published, titled “Feasibility Study of Future Energy Options for Great Lakes Shipping.” The study assessed alternative fuels and power options in the region and developed a detailed profile of Great Lakes fleets, ports, and fueling infrastructure.
In November 2022 at the UN Climate Change Conference (COP 27), the US and Canada had announced their intention to develop a Green Shipping Corridor Network (GSCN) on the Great Lakes St. Lawrence Seaway System. In April 2023, GLS and the Canadian St. Lawrence Seaway Management Corporation co-hosted the first Collaborative Forum to discuss the development of a GSCN.
In early 2024, a Ship Alternative Fuel and Emissions — Toolkit (SAFE-T) was developed by Energy and Environmental Research Associates, LLC, funded by MARAD. The toolkit allows shippers to track fuel use and emissions, compare the carbon intensity of different shipping routes, and compare properties of conventional and alternative maritime fuels.
21. Investment decisions and operations to cut carbon emissions
Summary: Launched the $6.4 billion Carbon Reduction Program that gives states flexibility to pursue a wide range of emission-cutting strategies. Awarded $1.2 billion to projects that use American-made construction materials that have substantially lower lifecycle carbon emissions than typical materials. Adopted USDOT’s first-ever department-wide Buy Clean policy to prioritize low-carbon construction materials in federal procurement. Awarded $148 million to projects that reduce truck emissions at ports. Awarded nearly $200 million to port infrastructure projects that support offshore wind development. Made offshore wind vessels eligible for federal financial support through the Title XI Federal Ship Financing Program, promoting shipbuilding of vessels that construct and maintain offshore wind facilities. Optimized the descent path of aircraft to save millions of gallons of jet fuel per year at 53 airports. Finished testing NASA software that will efficiently manage air traffic and avoid over 75,000 tons of emissions each year. Selected a sustainable design for new air traffic control towers that will replace older towers at municipal and smaller airports.
Carbon Reduction Program
The IIJA established a new Carbon Reduction Program (CRP), authorized to make $6.4 billion available over five years to state and local governments based on a formula set by Congress. Secretary Buttigieg and FHWA launched the program in April 2022, laying out guidelines that gave communities a tremendous amount of flexibility to use this funding to cut carbon emissions. CRP dollars could be used for pedestrian trails, bike lanes, electric vehicle charging infrastructure, projects that support congestion pricing, truck parking facilities to reduce emissions from idling, energy efficient street lighting, port electrification systems, public transit projects like bus rapid transit and dedicated bus lanes, and much more. And if a state or local government had a project type that was not explicitly listed in the CRP guidelines, they could use CRP funding as long as they demonstrated to FHWA that the project would cut transportation emissions over the project’s lifecycle.
To be eligible to access CRP funding, each state (in consultation with local governments in their state) was required to submit a Carbon Reduction Strategy to FHWA by November 15, 2023 that identified projects that cut emissions. This strategy must be updated at least once every four years. In April 2024, USDOT published a report about states’ Carbon Reduction Strategies, which highlighted the diverse approaches to emissions reduction that state governments planned to pursue.
Some examples of the wide range of projects that used CRP funds:
- The Massachusetts DOT used nearly $20.6 million in CRP dollars to fund battery electric bus charging and maintenance infrastructure at the Quincy Bus Facility.
- In Richmond, VA, CRP dollars went toward funding RideFinders, a division of the Greater Richmond Transit Company (G R T C) Transit System. RideFinders is a non-profit ridesharing and transportation demand management agency that works to reduce the number of single-occupant vehicle trips in Central Virginia. This was just one of 34 projects that had already received CRP funding in Virginia as of November 2023.
- The Arizona DOT used CRP dollars to convert high-pressure sodium lighting to more energy efficient LED lighting in Maricopa County.
Low-carbon construction materials
The production of construction materials, such as steel and cement, is a major source of greenhouse gas emissions. So Secretary Buttigieg and the Biden administration sought to encourage and invest in materials that reduce those emissions. For example, state and local governments were allowed to use funding from USDOT’s Carbon Reduction Program (CRP) to procure sustainable pavements, as long as they use FHWA’s LCA Pave Tool to demonstrate that these materials would reduce lifecycle emissions compared to the typical materials that they would otherwise use.
With support from the Biden administration, the Inflation Reduction Act of 2022 established a brand new FHWA Low-Carbon Transportation Materials Grants Program, which was authorized to award $2 billion to projects that use American-made construction materials that have substantially lower levels of lifecycle carbon emissions compared to industry averages. Eligible materials included asphalt, glass, steel, and concrete used in transportation projects. In November 2024, Secretary Buttigieg and FHWA awarded $1.2 billion to 39 states through this new program.
In September 2022, Secretary Buttigieg announced USDOT’s first-ever department-wide Buy Clean policy to prioritize low-carbon construction materials in federal procurement. To make this announcement, the Secretary visited the Cleveland-Cliffs Direct Reduction Plant in Toledo, OH that produces hot-briquetted iron, which is a lower-emission alternative to prime scrap and imported pig iron for steelmaking (Image 21.1).
In October 2022, USDOT awarded $7.1 million to 25 states that participated in its Climate Challenge to quantify emissions from construction materials and design selection.
In April 2023, the Secretary and the FAA selected a sustainable air traffic control tower design that will use high-recycled steel and metal products.
Cutting emissions at US ports
Cutting air pollution at US ports was a key priority for Secretary Buttigieg and the Biden administration — not only because of the climate benefits, but also to improve the health and quality of life of residents who live near ports. Pollution at ports is especially problematic, because about 60% of large ocean-bound ships use extremely dirty heavy fuel oil, commonly known as bunker fuel. Local air quality is also impacted by emissions from the constant flow of truck traffic in and around ports, as well as emissions from port equipment, such as port cranes which typically operate by burning diesel fuel.
The IIJA created a new Reduction of Truck Emissions at Port Facilities (RTEPF) Grant Program, which was authorized to award $400 million over five years for projects that reduce emissions from idling trucks at US ports. These grants can fund:
- Port-related infrastructure that reduces emissions from truck idling;
- On-truck technologies that reduce emissions from idling;
- The use of zero or low emissions powertrains or fuels on trucks;
- Reducing truck congestion within or near ports, including through enhanced intermodal rail connections; and
- Port electrification and improving the efficiency of port operations to reduce emissions from idling trucks.
In April 2024, Secretary Buttigieg and FHWA awarded $148 million in RTEPF grants for 16 projects in 11 states and Puerto Rico. Examples of projects that were awarded funding:
- California was awarded $49.7 million to replace diesel- and gas-powered trucks and shuttle buses with zero-emission technologies, electric trucks, and EV chargers at the Ports of Long Beach, Oakland, and Los Angeles.
- Texas was awarded $26.9 million to cut emissions at the Port of Houston, funding 30 new zero-emission, short-haul trucks and portable electric chargers for battery electric trucks. The grant also funded the installation of new automated terminal operating systems to reduce truck idling times.
- Georgia was awarded $15.3 million to improve air quality at the Port of Savannah, funding a large-scale charging project near the port, replacing diesel-powered trucks, and expanding the use of low-emission and zero-emission equipment.
Secretary Buttigieg and MARAD also awarded grants through the Port Infrastructure Development Program to projects that cut emissions. Some examples:
- The Port of San Diego in California received over $11 million for a project that will enable ships to connect to the electrical power grid while alongside the terminal berth, allowing ships to avoid burning dirty fuel while at the port.
- The Port of Wilmington in Delaware received $50 million to construct a container yard with all-electric operations.
- The Port of Long Beach in California received over $30 million to replace diesel yard tractors with about 60 electric yard tractors, construct electric charging infrastructure with energy load management software to improve energy efficiency, and install software to improve the efficiency of cargo-handling operations.
- The Port of Seattle in Washington state received over $17 million to construct a new truck gate complex that will reduce emissions from truck idling.
Offshore wind
Secretary Buttigieg and MARAD facilitated the development of offshore wind projects. In June 2022, MARAD designated offshore wind vessels as Vessels of National Interest through the Title XI Federal Ship Financing Program (Title XI), which makes them eligible for federal financial support. This helped support US shipbuilding of vessels that construct and maintain offshore wind facilities.
Through the Port Infrastructure Development Program, Secretary Buttigieg and MARAD awarded nearly $200 million combined in 2022 and 2023 to projects that advance offshore wind deployment. Examples:
- In Staten Island, New York, the Arthur Kill Offshore Wind Terminal Project received $48 million to create a 35-foot-deep ship basin to support the adjacent offshore wind staging and assembly facility.
- The Baltimore County Offshore Wind Manufacturing Hub in Maryland received over $47 million to construct a roll-on/roll-off pad, a crane pad, ground improvements, geotechnical work, and steel structures to support components used in offshore wind projects.
- The Norfolk Offshore Wind Logistics Port in Virginia received over $39 million to convert an existing marine terminal and berth to an offshore wind logistics facility.
Sustainable aviation operations and facilities
Jet fuel usage and carbon emissions can be reduced by more efficiently managing air traffic. For instance, the FAA implemented Optimized Profile Descents (OPDs) at 53 airports in 2021 and 2022 — with these additions, a total of 64 US airports have had OPDs implemented. OPDs allow planes to glide down safely from cruising altitudes and use less fuel than the stair-step procedure for descents (Image 21.2). A study at Los Angeles International Airport estimated that OPDs saved about 25 gallons of fuel per flight, on average — on an annual basis, this translated to about 2 million gallons of fuel and about 18,500 metric tons of carbon emissions saved at this one airport alone.
In September 2021, the FAA and NASA announced the completion of research and testing on software that calculates gate pushbacks at busy hub airports so that each plane can roll directly to the runway and take off — which will minimize taxiing and ramp congestion and reduce fuel use. This software was developed by NASA and tested for four years by the FAA. As part of a larger investment in surface management technology through the FAA’s Terminal Flight Data Manager program, the FAA planned to roll out this new capability at 27 hub airports across the country, which would save over 7 million gallons of fuel each year and prevent over 75,000 tons of carbon emissions annually (Video 21.1).
The way air traffic control towers and airports are designed can also help to reduce carbon footprints. In April 2023, Secretary Buttigieg and the FAA announced the selection of a sustainable design for new air traffic control towers to be used at municipal and smaller airports. The FAA planned to use this design to construct an initial set of 31 control towers to replace older towers. The sustainability features include:
- All-electric building systems
- Materials and products free from chemicals known to pose health risks
- Thermally efficient façade
- High-recycled steel and metal products
- Renewable mass timber when usable
- Ground-source heating and cooling in some environments
Secretary Buttigieg and the FAA awarded numerous grants to improve the sustainability of airports. For example:
- In July 2022, the Dallas-Fort Worth International Airport was awarded a $35 million Airport Terminal Program grant to construct a Zero Carbon Electric Central Utility Plant, which broke ground in August 2023. The new electric utility plant was designed to provide heating and cooling to the airport, replacing a natural gas-powered plant and procuring electricity from 100% renewable sources. This project was part of the airport’s strategy to achieve net-zero carbon emissions by 2030.
- In February 2023, the Portland International Airport was awarded a $6 million Airport Terminal Program grant to convert its boilers that use fossil fuels with an electric ground-source heat pump, which is expected to be one of the largest heat pumps in Oregon. The new system will use electricity to pump water from the Troutdale Sandstone Aquifer, extracting heat from the water for heating and rejecting excess heat back into the aquifer for cooling. This will significantly improve energy efficiency and cut the heating plant’s use of fossil fuels by 90%.
- In August 2024, the Louisville Muhammad Ali International Airport was awarded a $34 million Airport Infrastructure Grant, part of which went toward funding a solar microgrid at the airport. The solar power system is expected to reduce the airport’s emissions by 68 metric tons per year, which is equivalent to the emissions from burning over 75,000 pounds of coal per year.
