Episode 5: Fuel for Thought
Introduction
There is a corn field in Decatur County, Indiana. About 60 miles southeast of Indianapolis. The corn was planted in late April. By mid-June it is knee-high. By August it is over your head. By October it is harvested, hauled to a biorefinery, and turned into ethanol.
Some of that ethanol becomes the E10 gasoline in your parents' car. Some of it gets shipped to gas stations across the Midwest. And some of it, between 2007 and 2022, went straight into the fuel tank of every car that ran in the Indianapolis 500.
For sixteen years, Indiana corn fields powered the world's most famous auto race. A few acres of corn from a farm you've probably driven past, burned at 230 miles per hour in front of 300,000 spectators on Memorial Day weekend.
Today the story is different. Since 2023, the Indianapolis 500 has run on a 100% renewable race fuel from Shell, made primarily from sugarcane waste in Brazil. The Indiana corn era at the Speedway is over. But Indiana corn is still the backbone of America's renewable fuel industry. And the story of how it got there, and where it's going, is the story of this episode.
Why Indy Burned Methanol for 40 Years
To understand why an Indy car runs on ethanol today, you have to understand why it ran on something called methanol for the previous 40 years.
If you listened to Episode 3 of this series, "Voices in the Air," you remember Sid Collins delivering an unscripted live eulogy on the radio after two drivers died in a crash on lap 2 of the 1964 Indianapolis 500. That crash, the one that killed Eddie Sachs and Dave MacDonald, changed everything about safety in American open-wheel racing. The fire was the problem. Gasoline burns hot, but it also burns fast and bright. And in a 1964 race car with the fuel tank right next to the driver, a gasoline fire was lethal in seconds.
So in 1965, the next year, the United States Auto Club, which was running the Indy 500 at the time, mandated a switch to methanol (Wikipedia, 2026). Methanol is an alcohol, like ethanol. But methanol has one critical property: it burns cleaner and cooler than gasoline. Methanol fires can be put out with water (Flow Racers, 2023). They produce less smoke. They are easier to manage in a crash.
But methanol had a problem that took 40 years to solve. The flames are nearly invisible. In daylight, you sometimes cannot see a methanol fire at all. Drivers, pit crews, and emergency workers can be burned by a fire they literally cannot see (Motorsport Explained, 2023). Methanol is also more toxic than gasoline. And here is the part that mattered to a lot of people: methanol is made from natural gas. It is a fossil fuel. It is not renewable.
For 40 years, from 1965 to 2005, the Indy 500 burned methanol. Every winner from A.J. Foyt to Dan Wheldon stood in Victory Lane after a race fueled by natural-gas-derived alcohol.
Then a driver named Paul Dana changed everything.
Paul Dana was an Indianapolis-based journalist who became an IndyCar driver. He believed in ethanol. He believed that if a 230-mile-per-hour race car could run on ethanol made from American corn, then a regular passenger car could run on it too. In 2005, he convinced a group called the Ethanol Promotion and Information Council, or EPIC, to sponsor his car (ESPN, 2005).
In 2006, Paul Dana was killed during practice for the Homestead-Miami race. He never got to race on ethanol. But the program he had championed went forward in his honor. That same 2006 season, IndyCar ran a transition blend: 90% methanol, 10% ethanol. And in 2007, IndyCar made history. Every single car in the Indianapolis 500 ran on what was advertised as 100% fuel-grade ethanol (Honda News, 2011).
The actual mix was 98% ethanol and 2% gasoline. The gasoline was added for two reasons. First, to make sure the fuel was not legally classified as drinkable alcohol. Second, the gasoline tints the flame slightly orange, so that ethanol fires (which burn nearly clear, like methanol fires) are at least somewhat visible (Flow Racers, 2023).
Dario Franchitti won the rain-shortened 2007 Indy 500. It was the first 500 in history run on a renewable fuel. The whole motorsports world was watching.
The Chemistry of a Cleaner Burn
OK, let's actually do the chemistry. Because if you understand what burns in an engine, you understand the difference between gasoline, methanol, and ethanol.
When any fuel burns inside a car engine, it is doing a reaction called combustion. Combustion is when a fuel combines with oxygen from the air, very fast, releasing a lot of heat. That heat expands the gas inside the engine cylinder. The expanding gas pushes a piston. The piston turns a crankshaft. The crankshaft turns the wheels. That is how every car engine, gasoline or ethanol, fundamentally works.
The difference between fuels is what they are made of, and what they leave behind.
Gasoline is a mix of hydrocarbons. A hydrocarbon is a molecule made of just two atoms: hydrogen and carbon. The hydrocarbons in gasoline have between 5 and 12 carbon atoms each. They are called things like octane, heptane, and toluene. When gasoline burns completely, the carbon atoms combine with oxygen to make carbon dioxide, the hydrogen atoms combine with oxygen to make water, and a bunch of heat comes out. The equation looks like this: hydrocarbon plus oxygen makes carbon dioxide plus water plus energy.
Methanol is different. Methanol is one carbon atom, four hydrogen atoms, and one oxygen atom. Its chemical formula is CH3OH. The fact that it already has an oxygen atom built into the molecule changes how it burns. It burns cooler. It burns cleaner. And critically, it does not need as much extra oxygen from the air as gasoline does.
Ethanol is similar to methanol, but with one more carbon and two more hydrogens. The formula is C2H5OH. Like methanol, it has an oxygen atom built in. Like methanol, it burns cleaner and cooler than gasoline. But ethanol has higher energy density than methanol, which means a gallon of ethanol releases more energy than a gallon of methanol. That is why, when IndyCar switched from methanol to ethanol in 2007, the fuel tank size could shrink from 30 gallons to 22 gallons (Wikipedia, 2026). The cars needed less fuel to go the same distance.
There is one more important number: octane rating. Octane is a measure of how resistant a fuel is to "knocking," which is what happens when fuel inside an engine ignites too early. Higher octane fuels can be compressed harder before they ignite, which means they can be used in higher-performance engines. Regular gasoline at the pump is 87 octane. Premium is 91 or 93. Pure ethanol is around 100 octane (Advanced BioFuels USA, 2023). That is why every IndyCar engine is tuned to take advantage of ethanol's high octane.
So here is the chemistry summary: ethanol burns cleaner than gasoline, burns more efficiently than methanol, has higher octane than both, and produces less greenhouse gas because the carbon atoms in the ethanol originally came from the corn plant pulling carbon dioxide out of the air. When the ethanol burns, that same carbon dioxide goes back into the air. The cycle is closed. This is what we mean when we call ethanol a "renewable" fuel.
Now, there are limits to this cycle. Growing corn for ethanol uses water, fertilizer, and diesel-powered farm equipment. Processing corn into ethanol uses electricity, often from coal or natural gas. So ethanol is not zero-emissions. But when you account for the full life cycle, corn-based ethanol produces somewhere between 30% and 50% less greenhouse gas than gasoline (Indiana State Department of Agriculture, 2024). That is a real reduction. And the newer second-generation ethanol, made from waste material instead of from food crops, produces 60% or more less greenhouse gas than gasoline (INDYCAR, 2023).
That second-generation fuel is what powers the Indianapolis 500 today.
Indiana's 15 Biorefineries
Let's come back to Indiana.
Indiana is the fifth-largest corn-producing state in the United States (Indiana State Department of Agriculture, 2024). Indiana farmers grow corn on roughly 5.5 million acres every year. That is more land than the entire state of New Jersey.
About 44% of Indiana's corn, almost half, goes to ethanol production (Indiana Corn and Soy, 2025). The rest goes to animal feed, food products, exports, and other uses.
Indiana has 15 biorefineries scattered across the state (Indiana State Department of Agriculture, 2024). A biorefinery is a factory that takes raw corn and converts it into ethanol and a bunch of co-products. Together, those 15 biorefineries can produce about 1.4 billion gallons of ethanol per year. That is roughly 7% of all the ethanol produced in the United States (Indiana Corn and Soy, 2025).
Here is how the process works. Corn arrives at a biorefinery by truck. The corn kernels are ground into a fine meal. Water and enzymes are added to break the starch in the corn into simple sugars. Yeast is added. The yeast eats the sugar and produces alcohol, the same basic biological process that produces beer or wine. After fermentation, the liquid mixture is distilled (heated and cooled in stages) to separate the ethanol from the water and solids. The result is high-purity ethanol that can be blended with gasoline at the pump.
The remaining solids do not get thrown away. They become a high-protein animal feed called dried distillers grains, or DDGs. Indiana ethanol plants produce about 3.2 million tons of DDGs each year (Growth Energy, 2025). That feed goes to Indiana dairy cows, beef cattle, and pigs. The corn oil pressed out during the process becomes industrial corn oil and is used in food, in soaps, and even in biodiesel. The carbon dioxide released during fermentation is captured and sold to beverage companies that put it in soda and beer. In modern biorefineries, almost nothing from the original corn is wasted.
This is the modern Indiana farm economy. A bushel of corn grown on a farm in Decatur County or White County or Carroll County leaves the farm as raw grain and arrives at the gas pump as a renewable fuel, with animal feed and beverage CO2 and corn oil as byproducts. The whole supply chain is local. The corn is grown in Indiana. The biorefinery is in Indiana. The trucks driving the ethanol to the gas station are usually fueled by other Indiana ethanol.
Indiana has 288 gas stations that sell E85, which is the same 85% ethanol blend that powered IndyCar from 2012 to 2022 (Indiana Corn and Soy, 2025). 93 Indiana stations sell E15, which is a 15% ethanol blend approved for most cars made after 2001. And nearly every gas station in Indiana sells E10, which is the 10% ethanol blend that has been the standard American gasoline since around 2010.
So even though the Indianapolis 500 itself stopped running on Indiana corn ethanol after the 2022 season, the connection is still there. Every time an Indiana driver fills up their gas tank, the fuel they buy almost certainly contains ethanol from one of those 15 Indiana biorefineries.
The Shell Switch: 2023
In May 2022, IndyCar announced a major change. Starting in the 2023 season, every car in the series would switch from E85 to a brand-new fuel: Shell 100% Renewable Race Fuel (INDYCAR, 2022).
The new fuel was developed by Shell, the global oil and energy company that had taken over as the official IndyCar fuel supplier in 2019. The fuel had two parts. The first part was second-generation ethanol made from sugarcane waste, sourced from a Brazilian company called Raízen, which is a joint venture between Shell and a Brazilian company called Cosan (INDYCAR, 2022). The second part was a proprietary blend of other renewable components that Shell has not publicly disclosed (Shell, 2024).
What is second-generation ethanol? It is ethanol made from the parts of a plant that would otherwise be thrown away. Sugarcane is grown in Brazil for sugar, but when you crush sugarcane for its juice, you are left with a fibrous pulp called bagasse. For decades, bagasse was burned for fuel at sugar mills or discarded. Second-generation ethanol production uses enzymes to break down the cellulose in bagasse, turning agricultural waste into liquid fuel. It is recycling, at scale (Advanced BioFuels USA, 2023).
Why does this matter for racing? Three reasons:
First, the new Shell fuel produces at least 60% less greenhouse gas emissions than fossil-based gasoline, according to Shell's own testing (INDYCAR, 2023). That is a bigger reduction than the corn-based E85 it replaced.
Second, the new fuel does not compete with the food supply chain. Corn used for ethanol is corn that could otherwise feed people or animals. Sugarcane bagasse cannot feed anyone. Using waste material is a better deal for the environment and for food security.
Third, the fuel is a proving ground. Shell is one of the largest energy companies in the world. They are using the IndyCar series to test technologies that they then plan to bring to consumer products. The high temperatures and extreme conditions of racing stress-test fuel formulations in ways a normal road car never could (Shell, 2024).
The 2023 Indianapolis 500 was the first major American motorsport race to run on a 100% renewable race fuel. Josef Newgarden won that race in the No. 2 Shell-sponsored car for Team Penske (INDYCAR, 2024). He won again in 2024. The fuel works. The cars are fast. The drivers report no difference compared to the E85 they had been racing on for over a decade.
There is one tension in this story worth naming clearly. The Indiana corn era at the Indianapolis 500 ended in 2022. The corn farmers, the biorefineries, the Indiana Corn Marketing Council that supported ethanol for so many years, lost their direct connection to the race. The new fuel comes from Brazil, not from Indiana. That matters. The economics of the Indiana ethanol industry have not changed much, because the overwhelming majority of Indiana ethanol still goes into consumer gasoline at the pump. But the symbolic connection between the Indianapolis 500 and Indiana agriculture is not what it was from 2007 to 2022.
This is how industries evolve. The story is bigger than any one race.
The Economics of a Bushel of Corn
Let's do some math.
A bushel of corn is a unit of dry volume. One bushel of corn weighs about 56 pounds and contains roughly 70,000 individual kernels. Indiana corn farmers, on average, harvest about 200 bushels of corn per acre (USDA, 2025).
When that bushel of corn is processed at a biorefinery, it produces approximately 2.9 gallons of ethanol (Indiana Corn and Soy, 2025). That is the chemistry: 56 pounds of corn becomes 2.9 gallons of liquid fuel.
So if you do the multiplication: 200 bushels per acre times 2.9 gallons per bushel equals 580 gallons of ethanol from one acre of Indiana corn.
Now let's compare that to the Indianapolis 500. Every Indy car has an 18.5-gallon fuel tank (Wikipedia, 2026). During a typical 500-mile race, each car will pit for fuel about 5 times. That works out to roughly 92 gallons of fuel per car. With 33 cars in the race, the entire Indy 500 uses about 3,036 gallons of fuel.
Divide that by 580 gallons per acre of corn, and you get 5.2 acres.
The entire Indianapolis 500 race, from 2007 to 2022, could have been fueled by the corn from a single 5-acre cornfield. Just 5 acres. To put that in perspective, an average Indiana corn farm is about 400 acres. So the entire Indy 500 ran on a sliver of one Indiana farm.
That is the kind of math that puts modern agriculture into focus. Modern American farms are extraordinarily productive. The same 5 acres in 1950 would have produced maybe 200 gallons of ethanol, not 3,036. Better seeds, better fertilizer, better farm equipment, and better biorefinery technology have made it possible to fuel an entire major sports event from a postage-stamp piece of land.
Now the economics. The price of corn in the United States fluctuates a lot, but let's use an average price of $4.50 per bushel (USDA, 2025). 5.2 acres at 200 bushels per acre is 1,040 bushels. 1,040 bushels times $4.50 is roughly $4,680 worth of corn.
The Indianapolis 500 generates somewhere between $400 million and $500 million in economic impact for the city of Indianapolis each year (Indianapolis Business Journal, 2024). That is a return ratio that no other agricultural product can match. A $4,680 fuel input generated $400 million of economic activity. The marginal value of that corn, when paired with engineering and racing and broadcasting, became extraordinary.
This is the kind of multiplier effect that makes Indiana such a serious player in the renewable fuel economy. Indiana ranks fifth in U.S. corn production but accounts for some of the most efficient ethanol production in the country (Indiana State Department of Agriculture, 2024). The combination of land, infrastructure, and industry creates real economic outcomes for Indiana farmers and Indiana communities.
Careers from the Field to the Lab
This entire pipeline, from cornfield to gas tank to race car, employs tens of thousands of people in Indiana. The careers are everywhere. And many of them require nothing more than the kind of education an Indiana high school student is already getting.
Let me name some specific career paths:
Agronomy. An agronomist studies soil, plants, water, and the chemistry of how a field produces a good harvest. Purdue University's College of Agriculture in West Lafayette offers an Agronomy degree that is one of the most respected in the country (Purdue College of Agriculture, 2025). Agronomists work for seed companies like Beck's Hybrids in Atlanta, Indiana, or for fertilizer companies, or for the Indiana State Department of Agriculture, or as private consultants to farmers.
Fuel chemistry. This is the field that Shell's Bassem Kheireddin and his team work in. A fuel chemist designs the actual molecular composition of a fuel, balancing octane, energy density, emissions, and cost. Most fuel chemists have a bachelor's degree in chemistry or chemical engineering plus a master's or PhD. The Schwitzer Award that Kheireddin and his Shell team won in 2023 is a real engineering honor given out at the Indianapolis Motor Speedway every May (IMS, 2023).
Biofuel plant operations. Indiana's 15 biorefineries each employ between 40 and 100 people. Plant operators monitor the fermentation tanks, the distillation columns, and the quality control of the finished ethanol. Most operator positions require a two-year associate's degree from a community college or technical school. Ivy Tech Community College has biofuel-related programs at multiple Indiana campuses (Ivy Tech, 2025).
Agricultural engineering. This is a hybrid of mechanical engineering and farm science. Ag engineers design the machines and systems used in modern farming, including the harvesters that bring in the corn and the trucks that haul it to the biorefinery. Purdue has one of the largest Agricultural and Biological Engineering departments in the United States (Purdue ABE, 2025).
Sustainability and supply chain. Modern energy companies need people who can track the full life cycle of a fuel: where it came from, what it cost to make, what its carbon footprint is. This is a fast-growing field that combines economics, environmental science, and data analysis. Both Indiana University and Purdue offer sustainability-focused programs.
Direct farm work. And of course, somebody has to actually grow the corn. The average age of an American farmer is 58 years old (USDA, 2024). Indiana, like every farming state, needs the next generation of farmers. Many of them will be the children of current farmers. But many will not. If you grew up in Indianapolis or Fort Wayne or Evansville and you have an interest in agriculture, there are programs at every Indiana community college and at Purdue specifically designed for first-generation farmers.
The economy that powers the Indianapolis 500 is a science economy, an engineering economy, a farming economy, and a business economy. All of those careers start with the basic high school subjects you are taking right now: chemistry, biology, math, and economics.
Wrap-up
Here is what I want you to take away from this episode.
The fuel in any car, anywhere, has a story. The gasoline in your parents' car came from oil pumped out of the ground, refined in a facility that probably also produces plastics, shipped through pipelines, blended with ethanol from somewhere, and pumped at a station owned by a major energy company.
The fuel in the Indianapolis 500 has the same kind of story, just told differently. From 1965 to 2005, it was methanol made from natural gas. From 2006 to 2022, it was ethanol, mostly from Indiana corn. Since 2023, it has been a Shell-developed fuel made mostly from Brazilian sugarcane waste.
The story is not just about racing. The story is about chemistry. About agriculture. About economics. About the trade-offs every society makes between cheap and clean and reliable and renewable. The story is about whether you are willing to look at a thing as familiar as a gas tank and ask: what is in here? Where did it come from? Who made it? And what is going to be in here in 20 years?
The Indianapolis 500 has been a proving ground for those questions since 2007. Every year, the world watches what happens at IMS, and what happens at IMS shapes what shows up at the gas pump down the street from your house a few years later. That is what Paul Dana believed. It turned out he was right.
If you want to learn more, the teacher packet for this episode includes worksheets on chemistry, math, agriculture, and the career pathways I just talked about.
Sources
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