Senator David Koehler introduced the Illinois Clean Transportation Standard Act, Senate Bill 41, in January 2025. The bill would require transportation fuel producers to reduce the carbon intensity of their fuels by 25 percent below 2019 levels within 10 years and would support the transition from fossil fuels to cleaner fuels.
The Great Plains Institute commissioned analyses to better understand the potential benefits of the proposed program. According to these analyses, the Illinois clean transportation standard (CTS) would generate significant economic and public health benefits while reducing greenhouse gas emissions from the transportation sector.
Key takeaways:
- Illinois’s proposed clean transportation standard program would speed the transition from fossil fuels to cleaner fuels, reducing greenhouse gas emissions, improving air quality in every county, and spurring billions in clean energy economic activity.
- The CTS would achieve between $330 million and $687 million in health benefits through improved air quality.
- By 2040, the CTS would result in $41 billion in cumulative economic output, support 114,000 new clean energy jobs, and generate $622 million annually in labor income.
Illinois’s proposed clean transportation standard
Multiple states—including California, Oregon, and Washington—have implemented CTS programs, and New Mexico is currently undergoing a rulemaking to implement its own program. No Midwestern state has taken such action to reduce statewide transportation-related greenhouse gas emissions, but with Illinois, Michigan, and Minnesota all considering CTS legislation, the race is on.
Illinois’s proposed CTS policy would require fuel producers to reduce the average carbon intensity of transportation fuels by at least 25 percent below 2019 levels within 10 years of adopting the rule. This would reduce the use of high-carbon fuels like gasoline and diesel and drive investment in a variety of cleaner fuels, including low-carbon biofuels, hydrogen, and electricity.
Improving air quality in all Illinois counties
According to a new report from the American Lung Association, nearly half of people living in the United States are exposed to unhealthy levels of air pollution. Pollutants like particulate matter and ozone lead to health impacts like asthma attacks, heart attacks, strokes, preterm births, lung cancer, and impaired cognitive functioning. The transportation sector is a major source of these harmful pollutants, but transitioning to cleaner fuels provides an opportunity to reduce health impacts.
According to an analysis performed for the Great Plains Institute by Dr. Paul Meier from the Holloway Group at the University of Wisconsin–Madison’s Center for Sustainability & Global Environment, the Illinois CTS would improve air quality in all Illinois counties by accelerating the adoption of electric vehicles and other low-carbon fuels.
Dr. Meier utilized the US Environmental Protection Agency’s CO-Benefits Risk Assessment (COBRA) Risk Assessment Health Impacts Screening and Mapping Tool to quantify how the CTS would impact concentrations of particulate matter and ozone in the atmosphere and the resulting health benefits. COBRA estimates the economic value associated with adverse health impacts such as hospital visits, lost workdays, and premature death.
Compared to a reference case without a CTS, the policy would achieve between $330 million and $687 million in annual health benefits through improved outdoor air quality. By reducing emissions of particulate matter and ozone, the policy would reduce the incidence of premature mortality by 25 to 47 deaths each year.
For more information about the potential health benefits of Illinois’ proposed CTS, download our fact sheet.
Download factsheet
Driving Illinois’s clean fuel economy
In addition to reducing greenhouse gas emissions and improving public health, the Illinois Clean Transportation Standard program would support the state’s local economy. According to modeling conducted by Horizon Climate Group for the Great Plains Institute, the program would create net positive economic impacts in Illinois due to investments in biofuels and electric vehicle infrastructure, increased availability of lower-cost, lower-carbon fuels, and increased electricity sales.
Horizon Climate Group utilized the IMPLAN (impact analysis for planning) model for this study. IMPLAN is an input-output model that estimates a policy’s economic impact on a jurisdiction through direct, indirect, and induced economic activity. According to the analysis, the policy would result in $41 billion in cumulative economic output through 2040.
The clean transportation standard would reduce reliance on imported oil and increase the use of homegrown energy like biofuels and electricity. Over 15 years, it would create 114,000 new jobs in the clean fuel industry statewide and generate $622 million annually in labor income.
Through annual credit revenue, the program would generate the following benefits for clean fuel-producing sectors:
| SECTOR | AVERAGE ANNUAL BENEFIT |
| Electricity producers | $1 billion |
| Ethanol producers | $234 million |
| Biodiesel producers | $269 million |
| Renewable diesel producers | $53 million |
| Biofuel farmers | $43 million |
| Renewable natural gas producers | $479 million |
| Hydrogen producers | $112 million |
For more information about the potential economic benefits of Illinois’s proposed CTS, download our fact sheet.
Download factsheet
Next steps for Illinois’s CTS policy
The 2025 Illinois legislative session ended on May 31. Senator Koehler continues to work with stakeholders to increase support for the policy, and the legislature will convene again in Springfield, Illinois, for the veto session in the fall.
