It takes a good deal of power...
It takes a good deal of power to drive a car at this attitude at speed. Everything has to be functioning well and all of the various systems on the car have to be operating at peak form. Alcohol fuels can deliver reliable, consistent, and repeatable power levels.
The use of alcohol as a fuel in race cars, specifically Open Wheel and in some closed wheel cars, has been a standard for many years.
What most of us don’t realize is why? When comparing alcohol to gasoline it’s not readily obvious why one would select alcohol over gasoline. For purposes of this story when we refer to alcohol we mean methanol or ethanol. Gasoline is much denser from an energy content perspective, meaning it takes less gas (versus alcohol) to make the same power. It’s easier to ignite gasoline than alcohol fuels. Gasoline is available all over the world, the quality may be different, but it’s available. Gasoline is also more compatible with the materials that are currently used in the construction of fuel systems in use on the road today, from vehicles to the infrastructure used to move it from producer to customer.
The characteristics, between the gasoline’s used in say an F1 car are worlds apart from what we use in Saturday night racing. It would be easier to get a date with Angela Jolie, even if you weren’t supplying the baby sitter, than to buy 55 gallons of the “Gasoline” used in a F1 car. It’s pretty much unobtainable to the average racer. That said, we’re still able to buy racing gasolines that are a far cry from what is available at the pump today. We have at our fingertips, and our wallets, some of the finest racing fuels that have ever been offered to the racer at any time in history. We are a truly lucky lot. While we pay for this privilege, the cost is reasonable given the amount of technology and infrastructure it takes to deliver these high quality products.
We need to look back at why alcohol was even introduced to the racing community. It boils down to one word: safety. Yes, there are other benefits but the fuel was really legislated into use due to perceived safety benefits. The great things about gasoline and its use in racing engines, is also why it’s inherently a riskier fuel than alcohol, gasoline will ignite in less than ideal conditions, as in outside the engine. And, once it’s lit, it’s harder to extinguish outside of the controlled burning that is taking place in the combustion chamber.
It’s clear that the flames...
It’s clear that the flames from alcohol are truly invisible in the bright light of day. If you look closely (in the upper left side of the picture) you can see how the light is being refracted by the heat as the alcohol, in this case methanol, is burning in the small metal dish. If this was a fire in a race car during the day you wouldn’t be able to see the flames from the alcohol until some other part of the car was burning.
If you have ever been present when a race car catches fire it’s a truly scary event, regardless of the fuel used. But gasoline is a bit more intense. The bright orange of the fire, the very intense heat, and the fact that spraying water on the fire does very little to it other than spread it around. I’m not suggesting banning gasoline as a fuel for racing; I’m just stating a fact. The fact that fires are a very rare occurrence in today’s race cars is a testament to the safety that is designed into the modern race car, at all levels of the sport.
A car that is fueled by alcohol is no less scary should it catch fire, but there are a few critical differences. The fire is much easier to extinguish with water-based fire extinguishers. In fact, water is the fire extinguisher medium of choice for alcohol fires. There is less need for special extinguishers to be used outside of the car itself.
This goes back into our racing past, in 1964 when there was a crash and a terrible fireball due to a ruptured fuel tank, early in the Indy 500 and two prominent IndyCar drivers of that time, Eddie Sachs and Dave MacDonald, perished as a result of that fiery crash. The following year (1965) all the cars racing under the USAC banner, including the 500, were powered by methanol as the use of gasoline was banned.
Some other alcohol facts that make it a bit safer from a fuel perspective: It burns at a much cooler temperature and slower than gasoline. Consequently, this slower burn rate, around 18 to 22 percent slower depending on the conditions, results in an open fire that is a bit less intense and easier to control with easily obtained firefighting equipment. Please do not confuse this as a “safe fire.”
The same bowl, the same amount...
The same bowl, the same amount of alcohol, only this time at night. The flame is a glowing almost neon blue. While people may talk about how cool, from a temperature perspective, alcohol burns. Make no mistake, this fire is hot; hot enough to do some serious damage to a race car and its valuable contents: the race car driver.
But not everything is all roses and honey, from a safety perspective. In the light of day, it’s almost impossible to see an alcohol flame. While it’s easier to extinguish an alcohol fire, first you have to see it. Often times you will see the driver or crew reacting to the fire before any pit personnel can see the flames. Their reaction is due to the fact they are being burned. Think back to the Indy 500 when Rick Mears was burned by a fire ignited during a pit stop. This was the genesis of IndyCar teams squirting water on the dry break fuel valve right after it’s disconnected from the car as a fire mitigating process. As a fuel, alcohol is to be treated with the same respect as any other fuel. It’s dangerous and can cause some serious injuries just like any other combustible liquid.
For the racer there seem to be many positives for using alcohol as a fuel; are there any downsides? Yes, there are a number of issues that alcohol brings to the party that are not even considerations with gasoline fuels. The first is that alcohol is hygroscopic. It will absorb water out of the air if it’s exposed to the environment. This little feature can make a perfectly acceptable jug of fuel not worth using if the water content gets too high. This feature of alky fuels is, and has been, the bane of many tuners as they make changes to the fuel system only to find that the fuel was contaminated with water.
This is also a real problem in areas that have a good bit of humidity in the air. In the Southwest it’s not a big issue but it still means that any alcohol that is stored needs to be in containers that are not vented and that the fuel should not be exposed to the environment any longer than possible.
Another downside is that many of the rubber type seals that are used in gasoline fueled cars don’t hold up when the fuel is changed to alcohol. They don’t react well with alcohol fuels, often degrading and no longer offering an acceptable seal, or even worse they degrade and contaminate the fuel downstream of their location. While this seems like a real issue, it’s simply rectified, by using seal materials that are resistant to alcohols, from the tank to the end of the fuel delivery system.
The chemical makeup of alcohol is very corrosive to many of the coatings that are typically used on metals in the fuel system. It’s not uncommon for metal components to get surface oxidization and pitting as a result of alcohol fuels. This becomes a real issue if the alcohol is allowed to sit in the fuel system between races. The fuel system should be maintained between races to prevent the alcohol in the system from turning into what is a very strong corrosive agent.
If the fuel system isn’t cleaned frequently, preferably after each race day, the corrosive nature of alcohol will play havoc with the metal and rubber components in the fuel system, especially those components not designed for this type of fuel. This isn’t a real issue as most racers who are using alcohol fuels are already familiar with the required maintenance. For those not familiar with the maintenance rigors required when using alcohol fuels; education comes quickly and with a vengeance.
Butanol has some unique characteristics; it’s the one alcohol that most closely mimics gasoline from an energy density perspective. Its stochiometric air/fuel ratio is the closest to gasoline. Due to its chemical makeup, butanol isn’t as corrosive as methanol or ethanol. While all of this sounds great, there are some issues that prevent butanol from being a viable racing fuel at this point in time. First, is that it has a fairly high melting point and at cooler room temperatures more closely resembles Vaseline than a liquid fuel. However, it does mix well with gasoline and that has some real positives for the passenger car world; however it’s not a real boon to the racing world, yet. At this time we will still focus our attention on methanol, while ethanol is gaining more acceptance.
Failure to properly maintain an alcohol fuel system will result in, aside from the corrosion, a grit like substance, almost a fine sand type of residue, in the lines and around aluminum parts. This grit is the result of an increased electrical conductivity that alcohol has over gasoline fuels. The grit is from the galvanic corrosion caused by the greater electrical conductivity from the fuel as it interacts with the various different metals in the fuel system. This contamination will migrate throughout the system clogging fuel filters, fuel jets, and generally cause havoc within the fuel system.
It’s often thought that alcohol makes power because it has a greater amount of energy. This isn’t exactly true; in fact, the type of alcohols that are commonly used in racing have less heat energy than gasoline based on the volume. There are, in fact, four types of alcohols of which only methanol and ethanol are currently used as fuels in the racing world. The other two types of alcohols, propanol and butanol, aren’t used commonly used. Propanol has more uses as an industrial solvent than as a fuel while Butanol is an interesting chemical.