Alternative refrigerants: which will be used in the future?
In the last few years, the refrigeration industry has carried out extensive research into alternative refrigerants able to meet the urgent need to reduce harmful emissions appropriately. This is a result of the fact that pollution caused by equipment such as air conditioning systems and refrigerators has, over time, become such a big problem that it can no longer be ignored or, much less, under-estimated.
European legislation on this issue has gradually become stricter, with the introduction of more and more restrictions (listed in Directive 517/2014), aimed at incentivising manufacturers to adopt low GWP (Global Warming Potential) refrigerants. Despite major steps being taken to improve the current situation, there remains considerable uncertainty as to future market trends.
Most widespread alternative refrigerants
As mentioned above, increasingly strict EU legislation is designed to gradually abolish high GWP refrigerants. For example, all refrigerants with a GWP above 2500 (such as R404A and R507A) have been banned since 2020, while those with a GWP of 1500 or above (R410A) are due to be banned from 2022.
Many chemical mixes have been tried in recent years in an effort to find the best performing one. They all have unique characteristics and several advantages, but none of them has so far prevailed definitively over the others. These alternative refrigerants can generally be sub-divided into two macro-categories as follows:
- natural refrigerants, including ammonia (R717), carbon dioxide (R744), propane (R290), isobutene (R600) and propylene (R1270);
- synthetic refrigerants, including hydrofluorocarbons, hydrofluoroolefins and mixes containing them, such as R32, R1234yf, R1234ze, R1233zd, R454B, R513A, R455A, R448A, R449A and R452B.
Refrigerants in the first category have minimal negative effects, or in some cases no effect at all, on global warming and are generally very efficient. However, they still have some defects, such as increased levels of inflammability, the potential to form dangerous mixes and the need for specifically created equipment designed to run on them.
Refrigerants in the second category have a low GWP, low toxicity and a reduced inflammability risk. However, their disadvantages include the fact that most of those listed are inodorous and heavier than air. This leads to increased safety risks in case of equipment failure.
The best refrigerants for the future
In the light of this information, it is clear that choosing the best alternative refrigerants to adopt in the coming years is no easy task. They all have pros and cons which make them efficient in certain operative environments but less reliable in others. How then is it possible to make a responsible decision for the future?
A determining factor that must be taken into consideration is undoubtedly the global warming potential. That parameter is at the centre of international debate on climate protection and will lead to increasingly stricter policies as the year 2030, the target date for reaching net zero impact, approaches.
In view of this scenario, it is wise to choose low GWP refrigerants such as the natural ones, as they are less likely to be subjected to future restrictions. In the right conditions and with systems constructed ad hoc, they are also able to achieve optimal performance levels. Furthermore, they are considerably less costly for companies.
In conclusion, it is also important to note that these substances have a higher risk of fire and explosion. It is therefore crucial to provide appropriate staff training for those who will have to handle them, as well as introducing innovative and modern equipment design and constant monitoring of the systems themselves.
