Friday, April 22, 2016

Earth Day: Help clean our air using cheaper "regular" gasoline


Every year on April 22 we honor Earth Day around the world. The day is celebrated by nearly 200 countries to honor and promote environmental preservation. Today I would like to tell you about gasoline, and how to breathe cleaner air and spend less money! But first, some history on why I chose today to lecture you on clean air.

In 1969 a massive oil spill in Santa Barbara devastated the coast. This was amidst a time of war protests and increasing concern with pollution and public health. A senator from Wisconsin named Gaylord Nelson had the idea to use this politically charged time to create a national day to teach about the environment through the media. He and his chosen bipartisan staff chose the date April 22 to be Earth Day, which fell between Spring Break and Finals.

Ultimately, public support for Earth Day led to the creation of the Environmental Protection Agency (EPA), raised support for the Clean Air Act, the Endangered Species Act, and the Water Quality Improvement Act. In honor of Earth Day, I encourage you to take one easy step any car-driver can do to improve air quality and save money – stop buying premium gasoline!

What is an Octane Rating? And why are they lower in Colorado?


Have you ever wondered what the difference between regular, premium, and super fuel is? What do the numbers on the pumps mean? 87, 92, 94? Nearly every car manufactured today is made to run on “regular” grade fuel – usually 87 octane (or 85 if you live at a high altitude like Colorado).  The numbers associated with fuel grade signify the “octane rating” of the fuel.

Octanes are a family of molecules made up of hydrogen and carbon atoms that are typically used in gasoline fuels. There are many forms of octants (isomers), but they are all volatile and very flammable, which is why they make a good form of fuel.

An octane rating or octane number measures how much compression the fuel can handle before it ignites (for you thermo nerds out there- it is related to activation energies and the Otto-cycle). In cars, if the fuel ignites too early, it will cause the engine to knock because the pistons are not operating in the correct order. So, the higher the octane rating, the better it is able to resist premature ignition and knocking. At higher altitudes, like in Colorado, because there is less oxygen the fuel is less likely to ignite prematurely, which is why they sell lower octane rated gasoline there (regular is 85).

When is the last time you heard someone’s engine knocking? I’m not sure I have ever heard it in person, only seen it in old TV shows and movies that took place over 30 years ago. This is because typical cars today are designed to run on gasoline with an octane rating of about 80. If you drive a luxury or sports car that requires higher compression- like cars with turbo power – you might need a higher-octane fuel.



As engines get older, sometimes deposits are left in the combustion chamber so higher octane is needed, but typically only an increase in two to four points. Modern cars have computer-controlled engines to adjust for such elements to keep your car running knock-free. Yay technology!

Why do so many people use premium gasoline?


40%  of the fuel sold in the U.S. is rated higher than 87, even though over 90% of cars on the road don’t need it. Before cars were made to withstand lower grade fuel and engines were controlled by computers, this was much more important. Now, buying premium fuel when your car doesn’t require it is nothing more than “throwing money away” in the words of David Cole, former chairman of the Center for Automotive Research.

Oil companies have made more expensive fuel desirable using marketing strategies. For example, just the way they are named tempts people into buying higher octane fuel. Who wants to buy regular when you could have “premium” or “super.” Typically regular gasoline is labeled with dull colors while the more expensive grades are labeled with bright, contrasting colors.

Some gas stations even get consumers to buy more expensive gasoline on accident, by placing the premium grades to the left of the regular grade, like the pump pictured here. Because we read from left to right, many people naturally assume that the lowest grade will be on the left, which is where their hand goes first.

If you aren’t sure what type of gasoline you should be buying, please read this informational website from the Federal Trade Commission for consumers.

Using higher-octane fuel does not give cars better gas mileage. In other words the same amount of energy is released no matter how high the octane rating is for gasoline. The only way to get more power out of your car is to change the compression ratio, which is the reason sports cars require premium fuel. If you want more power, you need a different car, not a different fuel.



But high Octane can’t hurt, right?


Wrong. Unfortunately, there is one HUGE environmental consequence to producing and using premium fuels that is seldom talked about. Producing high-octane fuel uses more energy during the refining process. In 1990, Energy Secretary James Watkins even proposed that the U.S. stop selling high-octane fuels to save 80,000 barrels of crude oil a day during the invasion of Kuwait.

Not only does producing high-octane fuel waste extra energy, when it is burned it releases extra toxins into the air. When cars were first made, lead was added to gasoline to increase octane and prevent knocking. Lead was banned from gasoline in the Clean Air Act (thanks Earth Day!) after it was found to cause neurological disorders and other respiratory problems. In the 1970s it was phased out and oil and gas companies needed to come up with a new way to increase octane.

Crude petroleum contains aromatic compounds benzene, toluene, ethylbenzene, and xylene, referred to as BTEX compounds. BTEX compounds are known carcinogens and are very toxic when inhaled- they wouldn’t let us go near them in any of our chemical engineering lab classes because of this. Oil companies found that by increasing the levels of BTEX compounds in gasoline, octane rating was also increased. So in the 1970s instead of using lead in gasoline, it was replaced with BTEX.


In the 1980s, when all gasoline contained much higher levels of BTEX compounds, the EPA found that that benzene concentrations in the air were at an all time high, 14 times higher than before it was added to gasoline. Other options that oil companies could have used instead of BTEX to increase octane were ethanol and ethers produced from wood and corn. But because those are not produced within the refinery, profit was higher using the dirtier and more toxic BTEX compounds.

In other words, by using a higher-octane fuel that you do not need, BTEX compounds are being released into the air that we all breathe every day, causing smog, and releasing compounds been shown to increase asthma, allergies, and even lung cancer.

View of Denver in a smog cloud

So, on this Earth Day I am challenging you all to start paying attention more to the gasoline you are putting into your car. NEVER use high-grade fuel unless your car really needs it. And even better yet, consider biking, walking, or taking public transportation! Or if you really need a super awesome fast car, get one of those awesome new electric Teslas, and take me for a ride in it!

And read this informative and hilarious comic by The Oatmeal about his first Tesla. 
Cheers to your brain and thanks for reading!

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