14 Dec 2017
In Australia, many of the industrial refrigeration and air conditioning equipment makes use of fluorocarbon refrigerants to aid the heat transfer process. Fluorocarbon refrigerants are actually synthetic chemicals that normally have a very high GWP (Global Warming Potential), and some even have the potential to inflict damage to the ozone layer if released to the environment.
Substitutes for these chemicals are accessible, which can aid to minimize some of the environmental risks. They are known as ‘Natural Refrigerants’ because these substances are also available in nature and these substitutes include carbon dioxide, hydrocarbons and ammonia. These substances were already used in the past as refrigerants for many years; however, they are now finding their way into applications where earlier fluorocarbons were the favoured alternative. Natural refrigerants offer twin benefit for the companies – by lowering their energy consumption, they not only curtail costs but also they aid to protect the environment.
Natural refrigerants are economical, and they are available in plenty and can cover almost all refrigeration including industrial refrigeration applications already present. Moreover, when compared to synthetic refrigerants, natural refrigerants have a very low GWP. This reason is sufficient to recommend their use. Nonetheless, it’s equally essential that they are highly energy-efficient because over 80% of the GWP presented by refrigerating and air conditioning systems are the outcome of system energy consumption, and not due to refrigerant leaks. As of today, roughly 15% of Global Power Consumption is used to generate refrigeration, which results in great savings potential. Steps to saving energy throughout the complete service life of refrigerating systems are attaining more prominence and can aid substantially to reduce the yoke on the environment.
As far as the future is concerned, all things point towards the use of natural refrigerants in both economic and ecological terms, to shield both the environment and capital expenditure in the long term. Indeed, natural refrigerants have caught the spotlight due to their exceptional environmental credentials. Way back in history, naturals were the original refrigerants. Before some 100 years or so, at the beginning of the mechanical refrigeration – carbon dioxide, ammonia and hydrocarbons were amongst the few available alternatives to work with for the cooling industry.
The physical properties of natural refrigerants made it quite hard to handle, so they fell out of preference. Hydrocarbons are combustible, ammonia is toxic and carbon dioxide is a high-pressure gas; however, they have vital plus points to their credit. Ammonia has no GWP value at all and hydrocarbons and carbon dioxide have a low GWP.
When HFC (Hydrofluorocarbons) refrigerants came under the analysis of the regulators, once again the industry looked towards naturals as the probable solution. Every natural refrigerant has its place in the system, and hydrocarbons, CO2 and ammonia are all exceptional alternatives when used in the proper application.
The Bottom Line
Possibly, it’s prudent to say that engineers, as well as end users, may require reviving their memories about the right applications. End users ought to look cautiously at what is for every individual project, as naturals may not be the right fit for all type of installations.