Scottish OEM Star Refrigeration has produced a short online guide for refrigeration system owners that highlights the challenges and opportunities associated with ammonia (R717)- and CO2 (R744)-based technologies.
The guide is designed to help businesses assess the most appropriate long-term refrigeration option for their needs as they adopt more sustainable practices in response to evolving legislation, such as the EU F-gas Regulation.
According to the manufacturer, decisions surrounding refrigeration systems must balance competitiveness, compliance and application. Factors to consider include cooling capacity, budget, safety protocols and long-term operational efficiency.
“We’ve seen increased interest in natural refrigerant solutions following the EU’s draft F-gas Regulation proposal, which further restricts the production and consumption of synthetic fluids with high global warming potentials,” explained Dr. Rob Lamb, Sales and Marketing Director at Star Refrigeration, in a statement on its website.
“This has predominantly resulted in an increased interest in the use of CO2 and ammonia across a wide range of applications, temperature and capacities,” he added. “There is no silver bullet that suits all these applications and while CO2 is suitable for some applications, ammonia is better suited for others. In some cases, a combined approach may be the optimal solution.”
“We’ve seen increased interest in natural refrigerant solutions following the EU’s draft F-gas Regulation proposal. This has predominantly resulted in an increased interest in the use of CO2 and ammonia across a wide range of applications, temperature and capacities.”Dr. Rob Lamb, Star Refrigeration
Ammonia vs. CO2
Star Refrigeration has worked with ammonia- and CO2-based refrigeration and heating technologies for over 50 years. Previous projects include a low-charge R717 chiller for a U.K.-based dairy farm and a R744-based refrigeration system for a Scottish brewery’s cold storage facility.
In collaboration with international component manufacturers, the company designs and produces systems that deliver “optimal energy performance” and significant maintenance cost reductions across the lifespan of the equipment.
Star Refrigeration has said it works with end users to ensure they select the right refrigerant and system for their specific applications.
“It is crucial for businesses to carefully assess the technical, safety and costs implications associated with each option and choose the most suitable refrigerant and technology accordingly,” added Lamb. “Each refrigerant offers unique benefits for companies looking to reduce energy consumption and work towards net zero goals.”
According to the manufacturer, CO2 is particularly well suited to small- and medium-sized cooling capacities, as well as low-temperature applications. In addition to being a cost-effective option due to smaller components and piping, R744 also offers heat recovery potential to boost system efficiency.
Compared to ammonia, CO2 refrigeration systems can be more complex – due to the number of components – and have higher rates of electricity consumption, it added.
For larger industrial applications, Star Refrigeration recommends ammonia-based systems for their efficiency, longevity and “substantial life cycle savings.”
While ammonia is mildly flammable and toxic in nature, technological advancements in low-charge systems have helped address safety concerns, explained Lamb. The need for steel piping and heat exchangers can result in higher levels of capital expenditure.
Evolving f-gas regulations
As the European Commission, Council of the EU and European Parliament negotiate the terms of the upcoming revision of the EU F-gas Regulation, the HVAC&R sector awaits the outcome to learn how exactly how it will impact operations over the coming years.
“While the EU’s final decision to the proposed F-gas Regulation is not yet known, it is expected that the life-expectancy of HFCs and their blends will be shortened and that regulations to restrict their use through quotas and bans will be accelerated,” said Star Refrigeration. “[HVAC&R system] owners are looking for alternatives to HFCs to stay ahead of legislative requirements and avoid possible refrigerant price increases as the result of an accelerated phase-down.”
Star Refrigeration has emphasized the importance of informed decision-making with regard to selecting the right natural refrigerant options.
The manufacturer also noted that while the U.K. is not legally bound by the proposed EU F-gas Regulation update following Brexit, “the government is likely to follow much if not all of what the EU decides in order to ensure compliance with the Montreal Protocol and its own net zero emissions targets.”