R-290 Propane & Refrigerated Transport

The other day I was reading an article from Hydrocarbons21.com on the prospect of using R-290 propane in refrigerated transportation. The headline caught my eye and dragged me in. The company Transfrig has been experimenting with the idea of using R-290 propane in their refrigerated trucks. The idea is still in its infancy but I believe it has a lot of opportunity within the United States and the rest of the world.

The company Transfrig is based out of South Africa and has been around since 2002. They specialize in transport refrigeration and aim to be the number one choice for businesses within Africa. In recent years they have also expanded internationally to countries including Hong Kong, China, the Middle East, Libya, Liberia, Australia and Nigeria. In 2018 Transfrig was acquired by the automotive research group out of Paris known as Valeo.

The choice for R-290 for their new refrigerant was a unique one. They had originally looked at using R-744 but after some further research they decided they wanted to stay with a subcritical system. The hydrocarbon R-290 has been around for centuries and was one of the first refrigerants used before we saw CFC/HCFC refrigerants come to market. Propane is not going anywhere. It is also one of the best refrigerants out there when it comes to environmental impact. R-290 has a Global Warming Impact of only three and has no Ozone Depletion Potential.

Also, along with the lower GWP using R-290 for refrigerated transportation is more efficient then R-404A. In fact it has between a fifteen to twenty-five percent better coefficient of performance (COP) in medium temperature applications and between a ten to thirty percent COP increase in lower temperature applications. This increased efficiency also translates into around a sixteen percent savings in diesel usage. You get the benefit of having a very low Global Warming Potential refrigerant as well as having increased system efficiency for both the refrigeration system as well as the diesel engine.

The proposed unit from Transfrig uses a charge of only one point three to one point four pounds. That is an eighty percent decrease in charge when compared to your standard R-404A models. (A 404A unit could have between 6 and 8 pound charge.) Not only is R-290 cheaper then R-404A but you will also need less per recharge.

Drawbacks

Obviously the biggest fear here when using a hydrocarbon like R-290 is the chance of ignition. Over the evolution of refrigerants certain countries have adopted use of hydrocarbons in everyday use while other countries, like the United States, have shied away from mainstream hydrocarbon usage. Here in the US we have always preferred safety over climate, but times are changing and the push for climate friendly refrigerants are gaining traction.

The good news here is that there are a few good points here to help alleviate some of these flammability concerns. The first is that we had mentioned earlier the charge of these systems is quite small at less then two pounds. That is about ten percent of the propane that you’d find in your standard grill tank. (Yes, I am aware that propane used on grills and refrigerant are different.) The point I’m making here is that it is quite a small charge.

You can look at this another way too folks, almost all new cars nowadays are using the newer HFO 1234yf refrigerant. This refrigerant is classified as slightly flammable and the typical charge on a car can range between one to four pounds of refrigerant. So, you are looking at either the same, or even a smaller, charge then what is already in your car that you drive everyday. It puts things into perspective.

Transfrig also understands the concerns of possible ignition. To compensate for this have have installed a leak detection system that alerts the driver if the system falls below fifty percent charge capacity. If this does happen an alarm sounds and it is then recommended for the driver to pull over, open the container hold, and let it air out. After some time it can then be driven to a dealer for servicing.

The prototype unit was tested over a one year period on a refrigerated truck from the Ola Ice Cream Company based out of South Africa. The article at Hydrocarbons21.com puts the change of ignition at a thousand times less likely then that of an vehicular accident with the same truck. Throughout these tests there were no major issues found and since the test went so well the decision was made at Transfrig to migrate all of their refrigeration range of products over to the new R-290 design.

United States

As most of all you know HFC refrigerants, such R-404A, are on their way out. There has been countless debate and as back and forth on the United States’ HFC policies… but one thing is certain: HFCs do not have much longer and one of the top targets is R-404A.

Even if the Federal Government never comes up with an HFC phase down law it will not matter as there are so many states right now offering their own individual regulations and phase downs on HFCs. As the snowball begins to pick up speed we will see more and more states joining and mimicking other states policies. It will get to the point, if it hasn’t already, that it will not make financial sense to continue using HFC refrigerants. Why make one system for one state and another system for a different state? Business wise it makes sense to adhere to the strictest restrictions and be in compliance everywhere with your product.

So, what we will be left with is a hole for manufactures to fill. What refrigerants will be used instead of R-404A? In my opinion I believe R-290 has a legitimate chance. It makes sense. The only question now is can Transfrig truly prove their concept over the next few years… and if they do will United States government and importers take notice?

There are many folks who believe once a refrigerant has been chosen for an application then that refrigerant is it. Yes, it will never have one-hundred percent market share but it will have the lion’s share. There are many reasons for this but the biggest one is that it is just easier this way. Technicians only really have to become familiar with just a few refrigerants. There are very little surprises. Some of you may not agree with this statement, but we have a recent example to reference. Just look at R-134a’s transition over to R-1234yf. Yes, there are some outliers out there using R-744… but for the most part every new car is using R-1234yf.

Now that we are beginning to see the end of R-404A there is a hole in the marketplace when it comes to refrigerated transportation. Could R-290 fill this? There are a lot of hurdles to go through if Transfrig wishes to pursue. They have to test further. They have to roll trucks off the line and ensure there are no problems. Also, as I was writing this article I went and checked the EPA’s SNAP approved refrigerants on refrigerated transport. I was ninety-nine percent sure R-290 wasn’t approved… and I was right. So, they would have to through the EPA’s SNAP approval process as well before R-290 units could start being seen within the United States.

Conclusion

Let’s say though folks that we do end up seeing R-290 units in a few years across the globe and maybe even within the United States. What is the next step? If we are already using it in refrigerated trucks why couldn’t we use it in our vehicles as well? Remember how I said that R-1234yf was slightly flammable? Well… so is propane. The big difference here is that R-290 isn’t nearly as expensive as the HFO R-1234yf.

I’m going to throw some numbers out there and am also going to overestimate price on R-290 just so we can get a clear picture of the differences. Let us say that R-290 is about eight dollars per pound today. Then if we look at R-1234yf we can see that it is sixty dollars per pound. That is nearly a ninety percent savings when you go with R-290. Both refrigerants are flammable, both have very low Global Warming Potential, and both are Ozone friendly.

Now, I am not an engineer by any means, but I am wondering after researching this article… what is stopping us from using R-290 in our vehicles? If we can prove concept and go through the traditional SNAP approval process… why not? It would be an alternative to the 1234yf and it would save consumers a significant amount of money. What if, down the road, R-290 does get approved for vehicle usage? I could see a whole aftermarket industry dedicated to retrofitting away from 1234yf and over R-290.

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