CO2 The Natural Refrigerant Gaining Popularity

Well ladies and gentlemen it seems that we have come full circle in the past hundred years on refrigerants. We started with CO2 and now we’re circling right back to it. Every time I’m writing one of these articles about phasing out refrigerants I can’t help but chuckle. It seems that whenever we get close to the ‘perfect’ refrigerant something is found wrong with it. Either it depletes the Ozone, it has a high global warming potential, or it’s too flammable.

CO2 History

R-744 refrigerant, or CO2, was one of the first refrigerants invented and widely used in the late 1800s and early 1900s. We were using CO2 even before R-12 Refrigerant was invented. The idea of using CO2 as a refrigerant dates back to the 1850s and the first legitimate patent on CO2 was all the way back in 1867 Thaddeus S.C. Lowe. 

The idea was picked up again in Germany in the 1890s when Franz Windhausen of Germany designed the first carbon dioxide compressor and his design was purchased by J&E Hall of Great Britain. Here it began to see widespread use on cargo ships throughout Europe.  In America CO2 saw widespread use as well in ice machines, ships, and entertainment venues. Even the first movie theaters in the 1920s were cooled with CO2 refrigerants.

R-744 was eventually phased out due to two main reasons:

  • The Great Depression played a big part in the phase out of R-744. Refrigeration became a luxury that a lot of people just could not afford and the demand crashed.
  • R-744 is notoriously high pressure. Unfortunately, the technology in the early 20th century just wasn’t there  to keep the CO2 equipment running smoothly. The new R-12 Refrigerant was the easier choice as it did not have the high pressure complications that CO2 did.

CO2 is Coming Back

I’ve been watching the refrigeration industry over the past year and I am definitely seeing the trend of CO2 making a resurgence. The reason we’re seeing this is mainly due to the phase outs of refrigerants in the late 20th century and the early 21st century.

First we phased out the CFCs and HCFCs due to their ODP, or Ozone Depletion Potential. These were phased across the world in accordance to the Montreal Protocol and the world transitioned over to HFC refrigerants such as R-404A, R-410A, and R-134a.

Well now it’s been found that HFC refrigerants have an extremely high Global Warming Potential. So, now that we’ve spent all this time switching everybody over to the HFCs there is now a push to phase out the HFCs. The question is what is going to replace the HFCs?

There are many companies and experts suggesting various refrigerants and alternatives and one of those alternatives happens to be CO2.

Benefits  and Drawbacks of CO2

CO2 offers a variety of benefits when comparing it to the refrigerants that are in use today:

  • No Ozone depletion potential.
  • Global Warming Potential is 1. (R-134a is over 1,000)
  • Non-Toxic
  • Non-Flammable
  • Far more efficient than other refrigerants.
    • Save everybody some money on their energy bills!

Now, I am not an expert here but the only drawback that I can see on CO2 systems is that is a very high pressure refrigerant. Back in the day this caused a lot of parts to fail and fail often. However, I believe in the 21st century that we have the technology to utilize CO2 and to do it safely. Keep in mind that you will need specially designed systems to handle CO2.

Who’s Using CO2 Now?

I’ve found quite a few articles on recent CO2 usage and I even found a website specifically dedicated to CO2 that can be found at

I won’t go into detail about EVERY company that is using CO2 but here are some examples:

  • CO2 is used during the transportation/storage of ice cream and as most of you may know ‘Dry Ice,’ is CO2 in solid form.
  • Coca-Cola announced a few years ago that they would be discontinuing all usage of HFCs in their vending machines and would be transitioning over R-744.
    • Article can be found here.
    • Now, Coca-Cola fell short of their announced goal as you can read here, but as of today they have over 1.4 million CO2 vending machines on the market. This number is only expected to grow and other companies have begun to follow suit.
  • I found this article the other day detailing the first CO2 ice skating rink in Alaska. Ice skating rinks using CO2 is common place in Canada and is expected to spread in other parts of Alaska.
    Now, I have to say this… but why does an ice rink in Alaska need cooled? It’s freaking Alaska!

I can keep listing examples, but I feel that this gives a taste of what’s to come with CO2.

CO2 versus HFOs

Besides CO2 one of the other alternative refrigerants that is coming to market are the HFOs produced by DuPont and Honeywell. I won’t get too deep into this but I have a feeling that as time goes on we’re going to see a ‘war’ between CO2 and it’s HFO counterparts. Are we going to be using 1234YF in our automobiles five years from now or will we be using CO2? How about for our super markets? Even residential?  At this point it’s too early to tell what’s going to happen but it is exciting to see the innovation that is coming to the market.


As I stated in the beginning of this post it feels like we’ve gone in full circle…. and maybe that was how it was supposed to go. With this industry it feels like it’s impossible to predict anything. Regardless, CO2 is coming back and you best be ready!