Earth Day and the Critical Ingredient in a Can of Coca Cola

Happy Earth Day! Yes, the earth has its own special day, April 22.

Per custom and tradition, people everywhere do environmentally nice things.

Back on the first Earth Day in 1970, my ninth-grade class walked the roads near my school carrying trash bags and picking up litter. And no doubt, youngsters still do things like that today.

At higher levels of society, politicians give speeches on Earth Day. Or they hold international summits, like President Biden did earlier, to discuss with other bigshots how to protect the environment, if not save the planet.

Today at the Whiskey bar, we’ll celebrate Earth Day by discussing energy and energy storage.

But first, I think I’m going to pop open a can of Coca Cola.

Let’s dig in…

Pssst…. That’s the sound of me pulling the tab on that can of Coke.

Fzzz… That’s the sound of the compressed carbon dioxide (CO2) bubbling out of the drink.

Burble, burble… That’s the sound of me pouring that Coke into a tall glass filled with crushed ice.

And mmm…. That’s the sound of me taking my first sip, because sometimes a Coke sure tastes good.

And why is that, by the way? Well, it must be that so-called “secret ingredient” in Coca Cola that people talk about.

You’ve probably heard the tale about how only a few people in the world know the recipe for Coca Cola.

Rumor is that no one person knows the entire formula. Allegedly, there’s a cabal of chemists who must all come together and mix the magic Coke elixir — or something like that.

At any rate, that secret ingredient story has been the foundation of a marketing and branding effort that made Coca Cola iconic across the world. Until recently, of course, when the company decided to get all politically Woke on us; another story entirely.

And meanwhile, have you ever read the label on a can of Coca Cola? Ugh… Sometimes I can’t believe I actually drink that stuff. (Well, only on rare occasions anymore.)

Coke is mostly water with added sweetener; namely, high fructose corn syrup, or perhaps cane sugar in some bottling areas like Mexico or Brazil. By the way, the absolute best, most memorable Coca Cola I ever tasted was from a soda fountain at a restaurant in the Rio de Janeiro airport. Go figure.

Plus, Coke contains citric acid and of course CO2 to provide the fizz.

Finally, there’s that special, secret ingredient that gives Coke its unique flavor. Except they won’t tell you what it is.

But in honor of Earth Day I can tell you about one more special ingredient in a can of Coca Cola. It’s called “electricity.”

That can of Coke illustrates the idea of energy and energy storage, and I do not mean the sugar or corn syrup.

Because without electricity, you would not be drinking Coke from aluminum cans. Nor would you be eating or drinking much else that passes for food in this world considering how much of it comes in aluminum or aluminized packaging.

Indeed, without ample and affordable electricity, the materials used to package foods (certainly cans of Coca Cola) would simply be unavailable.

It helps to look at aluminum as something you could call “solid electricity.” The phrase may seem odd, but I’ll amplify it below.

It may help to recall that a while back we discussed the idea of money as a form of energy.

And in another context, we discussed how impoverished life can be absent ample, reliable supplies of electricity.

Today, and since it’s Earth Day, we’ll focus on how aluminum reflects the modern, global culture of energy.

Lose your energy system and you will lose aluminum. And there goes much of modern life.

Let’s unpack that point.

Start with some history. Aluminum was identified as an element in 1827. Back then, aluminum was extremely tedious and costly to refine. So throughout the 19th Century people valued aluminum as a precious metal.

In 1855, for example, the French showed off bars of aluminum alongside the Crown Jewels at the “Exposition Universelle” in Paris.

Almost three decades later, in 1884 aluminum was still so rare that architects placed a 100-ounce block of it atop of the newly built Washington Monument in Washington, DC. They specifically used aluminum instead of gold.

Yet today, aluminum is the second most-used metal in the world after only steel.

Think about that. It’s quite a historical change.

Again, across the multi-thousand year arc of history people knew about metals like iron, tin, copper, lead, gold, silver and more. But of aluminum? They knew nothing until just over a century ago.

Nowadays of course, aluminum is almost everywhere. You probably have a roll or two of foil in your kitchen. It’s probably in your refrigerator too, as cans of whatever.

Some of your house wiring might be aluminum. Along with the engine blocks of many cars on the road, if not the sheet metal of many car and truck bodies. Up in the sky, aluminum airplanes crisscross through the clouds. You get the idea.

And why is this? Well, people use aluminum because it’s a useful metal. It’s strong and lightweight, with mass about 40% less than the same volume of steel. It’s non-magnetic. It resists corrosion better than steel and conducts heat and electricity very well.

As for strength, here’s an example: much of the Saturn V rocket (the rocket that carried U.S. astronauts to the Moon in the 1960s and 1970s) was made out of aluminum. Is that strong enough for you?

Basically, aluminum is well-suited for many purposes. And at the end of its product-life, aluminum is relatively easy to recycle. It doesn’t lose its useful qualities when it gets melted down and recast.

Still, keep in mind that as social developments go, the use of aluminum is very new. For as ubiquitous and important as aluminum is to modern life, it is truly and only a metal of the electric age.

In other words, large scale aluminum use coincides with the widespread buildout of national and global electrical capacity. Meaning that if there’s no electricity, then you have no aluminum. It’s that simple.

It’s worth knowing that aluminum is the third most abundant element in the earth’s crust. Only silicon and oxygen are more abundant, and aluminum is the most abundant metal. (To be clear, we’re discussing the earth’s crust here, not the iron-nickel mantle or core.)

But despite its abundance in the earth’s crust, you don’t find aluminum free in nature. That is, you don’t walk in the woods and trip over a natural outcrop of aluminum. Molten aluminum doesn’t pour out of volcanoes, and it’s never deposited in hydrothermal vents.

The earth’s aluminum chemically combines with other elements (mostly via oxygen and silicon atoms) to form minerals and other compounds.

When it comes to mining ores and making aluminum, you begin with a rock called bauxite. Here’s what it looks like; nothing too special really:


Example of bauxite ore.

But obviously, bauxite ore will not hold Coca Cola.  For that, you must convert it into aluminum and then into cans. And that’s a complex, energy-intensive industrial process.

Depending on the quality of the bauxite ore, it takes about four to six tons to produce one ton of aluminum metal.

Industrially, aluminum is made via what’s called the Hall-Heroult process, which dates back to 1886.

Then, two 22-year-old scientists were working on opposite sides of the Atlantic Ocean. Charles Hall (1863-1914) of the U.S. and Paul Heroult (1863-1914) of France each independently made the same remarkable discovery. (And note that they shared identical years of birth and death.  How odd is that?)

They dissolved alumina in a bath of molten cryolite, a mineral composed of sodium, aluminum and fluoride. The resulting reaction produced aluminum metal.  The Hall-Heroult process is the foundation of the aluminum industry today.

Begin with a large steel container lined with carbon or graphite, called a reduction pot.  In most modern plants, pots are lined up in long rows called potlines. The world’s largest plants have well over 300 pots.

Then you run an electric current (direct current, as opposed to alternating current) through the mixture, which separates out metallic aluminum and leaves behind a cruddy, cryolite slag.

As you can surmise, the process uses large amounts of electric power. Thus, aluminum plants are almost always located near relatively inexpensive and available electric power, such as in the Middle East, Iceland, Quebec, Russia and other places with low-cost electric power.

The voltage can be low, in the range of only 5.25 volts. But the amperage has to be very high, usually in the range of 100,000 to 150,000 amperes and more. (An ampere is defined as one coulomb of charge flowing per second.)

One way to think of it is that the total equivalent power to keep just one aluminum pot running is between 700 and 1,000 horsepower.  That’s equivalent to the power generated by the engine of an M-1 tank, running full throttle — again, it’s per pot.

The electric current flows between a positively charged carbon anode made of petroleum coke and pitch, and a negatively charged cathode formed by the thick carbon or graphite lining of the pot.

This massive electric charge separates the oxygen molecules from the elemental aluminum, producing aluminum metal and carbon dioxide.

Molten aluminum settles to the bottom of the pot. At that point, the operating personnel siphon it off into crucibles.

All of this releases heat energy. Aluminum forms out of bauxite at about 900 degrees Celsius. But once the metal is separated, the melting point is nearer to 660 °C. In modern smelters, this “spare” heat goes to melt recycled aluminum that gets blended with the bauxite.

Overall, using recycled aluminum only requires about 5% of the energy that goes to make new metal from bauxite. So by blending recycled metal with new metal from bauxite, there’s considerable energy savings and efficiency.

Once aluminum potlines are up and running, the process is continuous. A typical plant runs 24 hours a day, year-round. It’s difficult to stop and restart a potline.

If a power failure shuts down aluminum production for more than about four hours, the metal in the pots will solidify.  Then each pot turns into a massive chunk of aluminum and cryolite gunk. Each pot has to be dug out and rebuilt, which is an expensive, time-consuming process.

Now I hope you can understand why I referred to aluminum as “solid electricity.”

And it brings us back to Earth Day.

There’s nothing wrong with celebrating nature. Everyone should respect our planet.

There’s nothing wrong with kids walking the roads, picking up trash.

Or at larger scale, there’s nothing wrong with figuring out what we’re doing wrong in terms of mistreating the environment and then working to rectify things.

But then we have those politicians and their hare-brained ideas like the looming, so-called Green New Deal, aka Green New Disaster which I’ve discussed in the past.

When it comes to energy in general, President Biden kicked off his administration by canceling an oil pipeline.

As things have unfolded, it’s clear that Biden and his appointees are waging war on the built energy infrastructure.

Just the Biden plan to transition the auto fleet to electric vehicles (EVs) will place immense strains on the overall energy system, whether from fossil fuels or on the electric side.

Meanwhile, the talk of building new “infrastructure” has devolved into an expensive pander to pork barrel spending and political payola.

One way or another, you should understand that massive stress is about to hit the national energy supply. And it will definitely affect electric power.

It’s one thing to have brownouts and times when the air conditioning system doesn’t work. But at a larger scale, imagine what happens when the ability to produce and use something as critical as aluminum goes away.

It gets us back to that simple can of Coca Cola at the beginning of this article. Just for one quick sip, a lot of bauxite had to go into the reduction pots, plus vast amounts of energy.

In other words, it’s not just some mythical “secret ingredient” of the Coca Cola corporation that makes it possible to have a Coke. It’s an entire global approach to delivering massive supplies of energy to users up and down many supply chains.

And it’s all at risk. So think about that as Earth Day plays out.

On that note, I rest my case.

That’s all for now… Thank you for subscribing and reading.

Best wishes,

Byron King

Byron King
Managing Editor, Whiskey & Gunpowder

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Byron King

A Harvard-trained geologist and former aide to the United States Chief of Naval Operations, Byron King is our resident gold and mining expert, and we are proud to have him on board as the managing editor of Whiskey & Gunpowder.

This “old rock hound” uses his expertise and connections in global resource industries to bring...

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