ACR Journal

August | September 2021 Volume 7 No.5 22 COMPRESSORS The compressor is an integral part of refrigeration equipment. Yet, despite the increased focus on the environmental credentials of the sector, innovation has not necessarily moved on at a similar pace. However, time does not stand still, and new solutions are needed to tackle the important issue of sustainability if the technology is to be fit for the future. Insofar as compressors are concerned, the refrigeration sector has seen little innovation in the last 40 years. To an extent, this is understandable – as the old phrase goes, if it isn’t broke, don’t fix it. After all, a primary, prioritising concern for refrigeration OEMs has always been ensuring their products are compatible with varying loads and temperatures and can operate at high pressures. If a solution fits this remit, this has traditionally been sufficient. As such, the current technology employed for compressors has usually been seen as the best choice for those in the industry. Used to control the circulation of the refrigerant throughout the equipment’s system while drawing vapour away from the evaporator at lower pressures and temperature for condensing, these are often picked solely for function. F-Gas and long-term sustainability The mounting legislative pressure on refrigeration OEMs to make equipment greener is significant and will only increase. Beginning with 1987’s Montreal Protocol, which outlawed chlorofluorocarbons (CFCs) and continuing with the 2016’s Kigali Amendment to gradually curb hydrofluorocarbon (HFC) use, the sector has been subject to gradually tightening environmental legislation. This has culminated in the F-Gas ban, which came into force in the UK and EU in January 2020 and banned any HFCs with a global warming potential of 2500 or over. The ban specifically applies to all refrigeration systems containing HFCs equivalent to over 40 tonnes of carbon dioxide. With this in mind, upheaval and innovation are patently required to adhere to this rapidly shifting legal landscape. This involves phasing out refrigerants with a high global warming potential (GWP), including R410A and R134A, alongside R404A. However, this is easier said than done. Though low-GWP refrigerants exist in ammonia and carbon dioxide, they require high-pressure ratios and extremely high absolute pressure for effective compression. Additional innovation required As innovation in the compressor space has stood relatively still for an extended period of time, there are still unanswered questions around whether current technologies can work with low-GWP refrigerants of the future. Indeed, traditional units may need to be daisy-chained to reach the parameters required to compress them, resulting in additional CapEx spend and further OpEx expenditure to keep additional units running. This is less than ideal and places additional pressure on the package size of the final product – a potential issue in a domestic setting. More research and development is required to build units that can effectively use low-GWP refrigerants without compromising on the final product experience for consumers. It could be said that the sector needs to consider a whole new approach to compression. Innovating in the refrigeration compressor space Nicol Low, chief operating officer at Vert Technologies, looks into the different factors refrigeration OEMs should consider when developing new solutions. Nicol Low