In a dedicated technical side event to Asia’s largest HVAC&R trade fair, leading compressor manufacturer Danfoss presented its vision of green solutions for light-commercial applications. R290 and R600a hold the biggest economic and ecological benefits for the Chinese market currently looking for viable alternatives to R22.
“We cannot afford to put too much development work into R134a - a refrigerant we know will not have a future in domestic appliances in longer terms. Instead we will mainly focus our work on solutions we know will have a good future, like iso-butane”, Dr. Heinz Jürgensen from Danfoss Germany told around 100 Chinese industry experts in a technical seminar at China Refrigeration – Asia’s leading trade fair for the HVAC&R industry.
Chemical refrigerants with a high Global Warming Potential, such as R134a or R404a, replacing ozone-depleting substances, would therefore not be a viable alternative for China, viewed from both an economic and environmental perspective. Hydrocarbons, by contrast, would combine energy efficiency and cost-effectiveness with investment security for Chinese manufacturers looking for worldwide export opportunities and domestic leadership.
Natural refrigerants - the “dream team” from an environmental & policy perspective
Based on a comprehensive historical overview of refrigerant choices over the last 150 years, Dr. Jürgensen stressed the fact that natural substances, including hydrocarbons, were there from the beginning to be now rediscovered as the only future-proof solutions in times of tightening environmental legislation worldwide on CFCs, HCFCs, and HFCs. Today, refrigerants could be grouped into three different categories, ranging from “controlled substances” without a future (CFCs, halons, HCFCs), and currently “allowed candidates” already facing increasing political pressure for phase out (HFCs), to the “dream team”, combining all natural substances (water, air, HCs, CO
2, ammonia). Within the last group, hydrocarbons would promise the highest potential for the Chinese market to replace R22 in light-commercial applications, due to their favourable pressure ratio, cooling capacity and COP, but also their ease of use and cost-effectiveness. Without doubt, R600a would be the future solution for domestic refrigerators worldwide, as already demonstrated in major markets, such as the EU.
Payback time for R290 VS models: 6 months
The Chinese refrigeration industry should not miss out on the opportunities the upcoming phase out of R22 is holding for manufacturers and exporters. Opting for iso-butane (R600a) and propane (R290) would enable the industry to focus purely on appliances development and refinement, and would open the door to other world markets already subject to strict emission regulations and HFC limitations. As no further refrigerant changes are to be expected with hydrocarbons, this would provide Chinese companies with needed investment security.
In different tests done by Danfoss to compare the energy efficiency of R290 variable speed (VS) compressors compared to R404a units in stainless steel freezers, multi deck reach-in cabinets, and open island freezers, results proved a 28%, 40%, and 39% energy savings respectively for R290 VS models over conventional refrigerant compressors. Using also Danfoss’ integrated control strategy, the latter would translate to a payback period of just 6 months for the slightly higher initial investment costs of R290 VS models.
Need for high-quality realisation
Dr. Jürgensen warned against the loss of efficiency in HC systems after using impure refrigerants, such as propane used for cookers. Using impure propane would set limits to the excellent thermodynamics, safety and proper functioning of systems that have been running on pure certified hydrocarbon refrigerants for more than 10 years.
Safety standard impeding the use of HCs in systems with charges above 150 grams at the international level are currently discussed among compressor manufacturers and end-consumers likely to join forces to propose new draft standards. The process, however, could take up to 5-6 years until inappropriate legislative barriers would be removed at a global scale.
