Can Aluminum Go Green?

Many emissions from Earth can cause warming, from cars to cows and a multitude of other things. Some of the top contributors to the warming are electricity power plants (40%), transportation (33%), farming, deforestation, fertilizers, and oil and gas drilling. An important single digit contributor is aluminum. It seems like such a clean and benign metal until you learn how it is made. 

In 1886, Charles Martin Hall discovered how to make aluminum, a very strong but light metal used today in countless applications. He formed a company and called it Alcoa. The technique he used was electrolysis, passing an electric current through a mixture of aluminum and oxygen called alumina.  

The process starts with the mining of bauxite. Bauxite is not a mineral. It is simply a sedimentary rock with a relatively high aluminum content. The Huntly mine in Australia, owned by Alcoa World Alumina, is the world’s largest producer.

The electric current passes through the alumina mixture in a large vat which has electrical anodes made of carbon bricks. The resulting chemical reaction causes the aluminum to be separated from the oxygen. Unfortunately, the byproduct is a huge emission of carbon dioxide into the environment. The whole process is very dirty and uses a huge amount of electricity. For every ton of aluminum produced, 11 tons of CO2 are belched upward.

The good news is employees, investors, and customers are demanding action to change the process so it produces “green aluminum”. The demands are especially strong from Europe’s Audi, BMW, and beer producer AB inBev. The industry has been trying to change the process for many years but was about ready to give up without progress. Things are changing now. Strongly aiding and abetting the effort has been Apple, which makes millions of aluminum-cased devices, and is committed to carbon neutrality across its facilities and its entire supply chain. 

Following a big push from Apple, Rio Tinto, and Alcoa, had a breakthrough and formed a new company called Elysis. The founders were able to replace the carbon bricks with an inert material. They are keeping secret what the material is, but they hope to license the new technique later.

There is a lot of enthusiasm about what Elysis is doing. I have no doubt some of the car companies will start promoting “green aluminum vehicles”. Retailers are already advertising green aluminum patio furniture and green aluminum foil. And, of course, aluminum cans are the largest single use of aluminum globally. We use about 180 billion of them every year. Companies are putting their money where there mouth is. Bloomberg reported in February buyers are paying a $14 per ton extra premium for the low-carbon aluminum.

Epilog: The United States Government is making a huge push on climate change. What I have written about in this article is proof positive industrial leaders around the world are pushing too. I am not saying no government help is needed but the power and speed of decision making by Apple, Amazon, Google, Microsoft, and many others shows they are not going to wait for Congress to agree on something.

Note: For any British readers, I hope you can tolerate me calling it a.LU.mi.num. I know you call it a.lu.MI.ni.um.