Insights Into The Next Generation HVAC And Refrigerant Future

There is an increasing demand for climate change which has forced the introduction of new regulations to reduce and restrict the impact of HFCs(hydrofluorocarbon) refrigerants. The industry leaders have been tasked with creating new refrigerants with lower global warming potential(GWP). Some of the alternative refrigerants being considered include natural options including R718, R717, propane, isobutene, and carbon monoxide and much more.

In the 1930’s the society demanded refrigerant safety which was achieved through the use of CFC refrigerants (chlorofluorocarbon). At the time, the gases were deemed safer and efficient as well as reliable compared to the available options. The introduction of CFC gases introduced a new standard of living in the society with improved human and food productivity, especially in the HVAC industry.

It has proven quite a challenge to come up with the best refrigerant that can be applied in the right areas at the right time to meet the regulation policies in place to reduce the impact of F gases. When looking for the best refrigerants to continue into the future, all the stakeholders are challenged with choosing options that provide safety, environmental friendliness and product sustainability needs.

For instance, a single manufacturer should choose a refrigerant with these specific requirements as well as blends in with design technology choices and guarantee a very competitive product for the chosen applications. Given the constantly changing global regulations about environmental issues, there are many challenges and uncertainties when choosing the next refrigerant to replace the phased out options.

In the 80’s and 90’s, non-flammable refrigerants with the best efficiency were applied in various industries to meet the societal demands to save the ozone layer at the moment. However, these demands have since changed thus the previously approved refrigerants are now being phased out. With the newly suggested options, there’s a great hope to reduce the global warming and ozone depletion impact.

Currently, numerous unsaturated refrigerants have been proposed but there is still research being done continuously so there are a few that have been discounted because of many reasons including toxicity.  As a result, many of the next generation refrigerants that have been proposed are still being evaluated and introduced in target markets to identify whether or not they have a lower ozone depletion and global warming potential. There is a chosen criteria that has been pointed out to be too narrow and might leave a few choices off the table.

Besides the thermodynamic features of a refrigerant, the performance also depends on the interaction with the proposed hardware in a real system. For instance, low pressure alternatives, especially those with a larger vapor in specific volumes might have large penalties especially from pressure drop in the heat distribution and exchangers compared to the high pressure options. Eventually, this will offset the higher efficiencies of thermodynamic nature.

However, there are some notable characteristics with lower pressure refrigerants that make them the best option for large chillers. For instance, they have a higher potential efficiency and also superior efficiency potential found in the centrifugal compressors. Note that, the higher pressure counterparts are used in compact practical designs because they have higher vapor densities thus they are applicable in both commercial and residential equipment.

That rule alone comes in handy when you’re comparing refrigerants of similar properties for a particular application. Equipment manufacturers have the responsibility of balancing the investment required to optimize their designs around the chosen refrigerants to provide the most efficient and economical products for use.

The introduction of CFCs in the 1930s was driven by the need to reduce safety risks of a personal and property perspective. These include toxicity and flammability issues from numerous refrigerants introduced at that time. R22, one of the refrigerants being phased out was used for over 6 decades because it has reduced flammability as well as toxicity safety. These safety parameters were achieved by the introduction of hydrogen in the molecules leads to atmospheric instability thus increasing flammability potential in different circumstances.

For instance, with R22, it is noted to be combustible in specific situations especially with pressure and air and it is advisable not to use it under those circumstances. In the 70’s the environmental authorities identified that while the refrigerants developed in the 30’s met all the safety requirements, they were causing ozone depletion, which was dangerous for the environment. As a result, there was a call to develop refrigerant blends with toxicity and flammability requirements set by the society while removing any ozone depletion concerns.

It’s challenging to determine the safety of refrigerants, especially with their flammability and toxicity concerns. The industry stakeholders are continuously examining the risks and potential benefits of each option. Today, there are some flammable refrigerants used in the smallest devices. The vehicle industry has adopted one of such refrigerants so the experience gained from the continued use will determine whether or not they are safe for the future.

When determining whether a flammable refrigerant is good enough to use, it is prudent to know that flammability is actually a continuum and it might be challenging to determine the various degrees of flammability on different refrigerant options. There are some proposed refrigerants that have a lower flammability potential. However, the society demands that non-flammability is the best standard to set.

The burning velocity was chosen as part of the criterion in determining the refrigerants for the future. That’s because stability will decrease with the ability of a flame to maintain its integrity or propagate. There’s a lot of ongoing research on the flammability risks associated with the burning velocity.

In conclusion, a lot of compromises need to be done with the product design or refrigerant applications from On the other hand, there might be costly product solutions to determine flammability safety and meet the low regulations with ozone depletion and global warming impact. Over the years, consumers were forced to settle with increased risk or complex products to allow the use of flammable refrigerants. However, some of the globally used refrigerants which meet the overall demands for high efficiency and safety in combination with low cost products might not be available to consumers or manufacturers.