(cars revving)
- It's the high-tech fuel used in race cars and dragsters.
And it comes from corn!
Ethanol.
(electronic whirring)
That's right, everybody.
Today we're doing a deep dive into
one of my favorite biofuels or fuel additives, ethanol.
Ready to get down and dirty on the bad stuff
and the good stuff, and we're gonna get to the truth.
Ethanol is basically ethyl alcohol,
the same type of alcohol found in alcoholic beverages.
But it's used as fuel.
Wow.
During production, starch from the plants is fermented
and distilled into sugars, which microbes turn into ethanol.
It's the same way you make beer or vodka
or moonshine, or, Eddie, what's your favorite drink?
Appletinis.
There's a couple of ways to make fuel grade ethanol,
but the most common is the dry mill method,
which is the same as my grandpappy's White Lightning recipe.
The grain passes through a grinding mill
and comes out as a powder.
A mixture made of this grain powder, water,
and an enzyme enters a high heat cooker.
This enzyme converts the starch into sugars
that can be fermented to create alcohol.
What's an enzyme?
Well it's a protein that can
take another chemical and change it.
Your saliva's got enzymes in it
that do a very similar thing.
Go eat a saltine.
Just chew on it, like, forever.
It gets sweet.
- Trust the process.
- Well, that's the enzymes in your saliva
turning the starches into sugars.
But we're making ethanol,
so the yeast is added to the sugar mixture
to begin the fermentation process.
Yeast digests the sugar, breaking it down into ethanol
and carbon dioxide, then a dehydration process
removes the water from the separated ethanol.
Often, small amount of gasoline is added
to the ethanol so that it's non-potable.
That doesn't mean you can't carry it around.
Means you can't drink it.
There's a bunch of laws out there
that say all the ethanol that's gonna be used as fuel
has to be made so you can't drink it.
I don't know, man.
Sounds like a dare.
Don't drink it, you idiots.
Then it's mixed with petroleum,
and the ethanol becomes fuel for your car.
Making ethanol a major player in
the fuel industry could have serious drawbacks.
It takes a lot of land to make not a lot of corn ethanol
and creating significant amounts of energy
from food crops would deplete the amount of land
available for growing actual food for people to eat.
You know, how people like to eat food that grows?
Each acre of corn can yield about
328 gallons of corn ethanol.
That's a lot of corn for not too much fuel,
so it's fine as a bridge or a supplemental fuel,
but it doesn't make a lot of sense as a primary fuel.
Ethanol blended gas is labeled
as E10, E15 and sometimes E85.
The number after the E indicates
the percentage of ethanol by volume.
So E10 has up to 10% ethanol.
All auto makers approve blends
up to E10 in their gasoline vehicles.
In 2011, the EPA began allowing the use of E15
in model year 2001 in newer gasoline vehicles.
E85, also called flex fuel, is an ethanol gasoline blend
containing 51 to 85ish percent ethanol.
E85 can be used in flex fuel vehicles,
which are specifically designed to run on gasoline,
E85, or any mixture of the two.
By volume, ethanol contains about
1/3 less energy than gasoline.
Drivers shouldn't really notice
a performance loss when they're using E85.
In fact, some fuel flex vehicles
perform better with more torque
and horsepower when they're running on E85
than when they're running on regular gas.
So we hit and few things here and there,
but what about the big question?
Is ethanol bad for your engine?
Sometimes.
- [Disembodied Voice] It has to; how can it not?
- [Disembodied Voice] No way, not a chance.
- In newer engines, E10 oxygenated gasoline
can be safely used with only minimal inconvenience.
Like a slight decrease in
miles per gallon and fuel efficiency.
But many other types of engines,
they're not designed to resist
the possible damaging effects of ethanol fuel.
Ethanol attracts water the same way
that I attract twice divorced,
chain-smoking patrons at Applebee's.
Oh, but their appetizers are exceptional.
Ethanol attracts and absorbs water,
including water from the air.
When it absorbs enough water,
fuel-water contamination occurs in the car's gas tank,
and that affects your engine performance.
If the car sits for a while, fuel separation occurs.
This is where the gas and the water
form layers in the gas tank,
and the motor sucks up the water layer into the engine,
which makes for some seriously costly damage.
Ethanol is alcohol,
and alcohol can cause corrosion in the fuel system.
Metal parts rust,
and plastic parts become deformed or cracked.
A lot of older cars especially
have problems with ethanol fuel.
But if you're driving your car enough
and your gas tank isn't crummy,
you probably don't need to worry about that.
And there's also the concern
that ethanol reduces the lubricating properties of gasoline,
which is true, to a point.
There's many people up in arms
alleging that ethanol in fuel is
ruining their engine for that reason.
But good oil companies take great pains
to make sure that their gasoline minimizes engine wear.
So modern gas in a modern car shouldn't be causing damage.
But up north where they're running two-stroke snowmobiles,
they're blaming ethanol for munching up
their engines, which makes sense.
Two-strokes need oil mixed with the gas to run right,
and ethanol cuts the the efficacy of lubricating elements.
They might be on to something is all I'm saying.
(dinging)
So why do we use it then?
Well, first, ethanol is extremely resistant to pre-ignition.
E85 is like a 105 octane gasoline.
So if you're not worried about fuel economy
and you got extremely high compression ratios
and you need super precise ignition timing,
well, you might wanna use a more ethanol-rich fuel.
Wait.
High compression?
Precise ignition timing?
Don't care how much fuel I use?
That sounds like a race car.
If you walk around the pits at a race,
it doesn't smell like gas.
It smells like ethanol, baby.
These cars are tuned to run on ethanol-rich fuels,
so they don't have the same concerns
about engine wear that I would in, say,
my 35-year-old Oldsmobile.
Also, gasoline blended with ethanol
burns cleaner than pure gasoline.
In here we got ethanol,
and in here we got gasoline.
Can you see it?
- [Disembodied Voice] No.
- See the difference in the flame?
- [Disembodied Voice] No.
- You can barely see that one.
Alright, it was too light outside
to see the difference, so we're gonna do it in here.
Cool.
Ethanol, gas.
Look at that.
Sweet, sweet flame.
So you can see how much cleaner ethanol is than gas.
Let's get back to the lab
and talk about other crap.
Ethanol cuts a car's greenhouse gas emissions.
The addition of ethanol to gasoline makes it an oxygenate,
which satisfies the requirements of the Clean Air Act.
So our ethanol makes our current tech
a little cleaner before the next thing takes off,
whatever that might be.
Fully electric, hydrogen, something else,
and then the internal combustion engine
becomes just like my happiness; a thing of the past.
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