Next Generation Refrigerants
While selecting a new refrigerant, a comprehensive assessment from various perspectives is necessary. Any substance must be carefully evaluated for ozone layer depletion effects and global warming potential (GWP), to check if it has a low overall impact on the global environment. It must also be assessed for energy efficiency, cost performance, safety, efficient use of natural resources and other factors…
Refrigerant based refrigeration & air conditioning industry has progressed in leaps and bounds in the last few decades as these equipment are providing the desired comfort and quality lifestyle to a large fraction of our populace. Environmental concerns (Montreal and Kyoto Protocols) related to the use of various refrigerants have become the hot topics for people with the degrading environmental health and its side effects on human, animals and vegetation on Earth. Since measures of the global warming are becoming urgent issues, various technical innovations and social system reformations are being promoted. In the engineering fields of heating, refrigerating, and air-conditioning, the global warming caused by the refrigerants is a big problem that must be solved. With strict climatic regulation enforcements in order to replace the refrigerant based refrigeration & air conditioning equipment as a whole and at once is a difficult task so efforts are always directed to develop new refrigerant free refrigeration & air conditioning technologies along with to develop new generation refrigerants with less potential towards environmental degradation.
As existing HFC or HCFC systems can’t be retrofitted to utilize the new refrigerants, so an outright ban on HFCs would be premature at this stage. New technologies and applications are constantly being developed that cater to HFOs. Over the course of the next several years or so, equipment will be developed for the use of next generation refrigerants, as more and more businesses phase out the use of HFC-oriented products in both design and construction. At the present stage, however, there are no perfect solutions for next generation refrigerants and heat pump or refrigeration systems by which the global warming is successfully prevented. Therefore, we have to search possible ways to the next generation. If there is to be a next generation of refrigerants in stationary equipment beyond hydrofluorocarbons (HFCs), it appears they will be hydrofluoroolefins (HFOs). And if that transition is to take place, it could be because of regulations or better energy efficiencies - or both. As the industry continues its evolution, one thing is for certain, refrigerant reclamation and recycling services are going to be even more vital in the near future. The transition to newer refrigerants will only be successful if the industry safely disposes of HFCs and HCFCs.
Next Generation Refrigerant
When selecting a new refrigerant, a comprehensive assessment from various perspectives is necessary. Any substance must be carefully evaluated for ozone layer depletion effects and global warming potential (GWP), to check if it has a low overall impact on the global environment. It must also be assessed for energy efficiency, cost performance, safety, efficient use of natural resources and other factors. Recent studies have confirmed that there is no single perfect refrigerant for all applications. It is therefore necessary to focus on selecting the best refrigerants for particular applications based on an overall assessment. Although there are various types of refrigerants, R-32 is a new refrigerant currently receiving the most interest. While R-32 also has an ozone depletion potential of 0, the refrigerant has only approximately 1/3 of the GWP of R-410A. Consequently, investigation of this promising next generation refrigerant has increased. At present, it is believed that, based on the refrigerant balance compared to other refrigerants, in some cases there is no better alternative than R32 (HFC32). According to research on split systems, HFC32 is currently considered to be the most promising substance for use as a next-generation refrigerant in both residential and commercial air-conditioners. Although it is an HFC, it has only about one-third the GWP of currently used HFC410A or HCFC22. It is also possible to improve energy efficiency of equipment by 10 % and to reduce the charging volume by 30 % compared to HFC410A. The use of R32 offers end-users the opportunity to benefit from class-leading energy efficiencies, excellent air quality and high comfort levels, while lowering the environmental impact of their heat pump system. As countries around the world look for suitable alternatives to HFCs, HFOs are set to become the new industry standard. Carbon dioxide (CO2) is also in consideration as a potential substitute; a number of supermarkets have already shifted to CO2 for their refrigeration systems, but the technology doesn’t yet exist for numerous systems that are more readily commercially available.
At present, HFOs remain the best option for most businesses and consumers alike. With the shift to a new generation of refrigerants, HFOs are set to become the new industry standard. However, because R-32 had been an extremely difficult refrigerant to handle, its use was not practical until now. Daikin became the world’s first company to succeed in applying R-32 to air conditioners by leveraging its expertise as the only manufacturer that develops and manufactures both air conditioners and refrigerants. Currently, R-410A is the refrigerant most commonly used in developed countries. However, if all R-410A were converted to R-32, the impact to global warming from HFCs in 2030 would be reduced by the CO2equivalent of approximately 800 million tons (19%) compared to the continued use of R-410A. Cooperation with governments and international organizations has expanded technical assistance for emerging countries to each region and aims for widespread use of the refrigerant R-32 throughout the world. Aiming for widespread use throughout the world, company not only manufactures and sells R-32, but it also provides technical assistance in emerging countries in cooperation with governments and international organizations. In India, verification tests were conducted for inverter type R-32 air conditioners. In executing training for the proper handling of R-32, the technical level also improved.
For the replacement of R-22, with a further milestone to help reduce the environmental impact of R&AC systems is possible with the development of a new lower GWP refrigerant technology for use in commercial refrigeration systems. Development work has revealed that XP10 offers the opportunity to be used alongside CO2 in hybrid systems - XP10 for medium temperatures and CO2 for low temperatures. Studies show that such a solution would provide retailers with a 90 percent reduction in direct carbon emissions and a minimum 50 percent reduction in the total carbon impact of retail commercial refrigeration systems when compared to the current global industry standard direct expansion (DX) technology based on HFC-404A. Retailers in some countries are already migrating from R-404A DX technology to 134a/CO2 hybrid systems in order to improve system energy efficiency and to reduce their overall carbon impact. XP10 is an efficient and logical choice in making a further step change reduction in carbon impact. It was stated that XP10 can also be used in stand-alone systems for smaller applications where hybrid systems are not practical, such as in discounter applications. A further benefit, it was reported, is that by adopting this new refrigerant technology in combination with systems using other low-carbon refrigerants such as CO2 or hydrocarbons, retailers can make a significant contribution to achieving the climate targets.
In Indian Context
India has a small carbon footprint at the individual level and its sustainable lifestyle results in low contribution of the country to overall emissions of greenhouse gases and ozone-depleting substances, as compared with other developed countries. However, there is an urgent need for developing new technologies indigenously as alternatives available today are patented apart from being expensive. A research based programme to look for cost effective alternatives to the currently used refrigerant gases is, therefore, essential. By establishing an effective collaboration between all important stakeholders, the initiative is focused on prioritizing areas of research in new refrigerant technologies and natural refrigerants. This shall help the country leapfrog from the current technology high GWP HydroFluoroCarbons or HFCs to technologies with lower climate impact.
The Ministry of Environment, Forest and Climate Change (MoEFCC) has announced an ambitious collaborative research and development programme to develop next generation, sustainable refrigerant technologies as alternatives to HFCs. This initiative will bring government, research institutes, industry and civil society together to develop long-term technology solutions to mitigate the impact of current refrigerant gases on the ozone layer and climate. With this initiative, India reaffirms its commitment to working with all other nations to safeguard the Earth's natural ecosystem. Some of the key players of the initiative include the Council of Scientific and Industrial Research (CSIR) and its allied institutions; Department of Science and Technology; Centre for Atmospheric and Oceanic Sciences; as well as key industry players in the sector.
AUTHORS CREDIT & PHOTOGRAPH
Dr S S Verma
Department of Physics
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