F-gas emissions: the truth behind a trusty refrigerant
– by Sebastiaan Jansen – 14/10/19
In this blog post, we take a look at one of the most controversial substances in the HVAC industry – F-gases – to ask: What are their origins? Are there alternatives? And what kinds of refrigerants should we use in the future?
What are F-gases?
F-gases, or fluorinated gases, transport heat and are used as refrigerants. The functioning of cooling machines is based on the evaporation and condensation of refrigerant, as shown in this illustration:
Not every substance is suitable for cooling purposes – only materials with a low evaporation temperature will do. Your refrigerator at home, for example, needs to maintain a temperature of around 7°C to cool groceries, and even less in the freezer compartment. This is the evaporation temperature required for the refrigerant used.
The American company Dupont was the first to introduce F-gases, in the early days of cooling technology back in 1920. They were considered very safe at the time, especially compared to the refrigerants that had been used in the first cooling machines (dating to the 1890s), which were very toxic and caused the machines themselves to deteriorate.
What is the problem with F-gases?
The early F-gases or chlorofluorocarbons (CFCs), known under the trade name freon, depleted the ozone layer, leaving the earth exposed to dangerous UV radiation which is harmful to people, animals and plants. Without the ozone layer, UV rays can cause damage to eyes, growth disorders and skin cancer.
In the late 1980s, highly industrialised countries agreed to phase out the production of all CFCs by the end of 1995 under the terms of the Montreal Protocol. Old refrigerants where replaced by the new, cleaner and more ozone-friendly hydrofluorocarbons (HFCs).
But the problems didn’t end there: F-gases have a greenhouse effect that’s a whopping thousand times that of CO2. In other words, they can trap a thousand times more heat at equal concentrations in the atmosphere. This is why the EU declared in 2015 that the production of F-gases would be reduced by 80% by 2030 – a reduction equivalent to 70 million tonnes of CO2.
What are the alternatives?
Most of the machines we deliver use the refrigerants R134a and R404a, which are globally recognised and easily available. Chemical companies are currently producing safer refrigerants that we will be able to use in the near future, but these are not yet easily available. The table below indicates their greenhouse effect relative to CO2, or global warming potential (GWP).
Most alternative refrigerants still have a relatively high GWP. To really make a change, we would have to switch to natural refrigerants, like:
- Ammonia (NH3), which has a global warming potential of 0;
- Carbon dioxide (CO2), which has a global warming potential of 1; or
- Hydrocarbons (HC), which have a global warming potential of 3.
There is a catch, however: the global warming potential of natural refrigerants may be very low, but they are either very toxic, highly flammable or have low energy efficiency. One cannot simply replace the refrigerant in an existing machine with natural refrigerants without serious consequences.
The future of refrigerants
There are several things to consider for boat builders and owners. First of all, most vessels are not bound by EU regulations, which means they have more time than the 2030 deadline. Of course, even so, there will be a point where all chemical F-gases will be phased out, as was the case with CFCs.
What does this mean for vessels that are now being delivered with R134a or R404a? Not so much: these refrigerants will still be available for service purposes until 2030 and even longer outside the EU.
Future vessels are looking at a challenge, however. Using low-GWP refrigerants which are flammable and have high toxicity levels means extra safety precautions. Chillers or cooling machines need to be placed in special rooms with toxicity sensors, fire dampers and other safety measures. Of course, we all need to contribute to ensure a cleaner future, and this is already being implemented in industrial installations on land.
If you have any questions about replacement refrigerants – for instance, if you would like to know which one best suits your particular vessel – simply contact one of our technicians. We would be pleased to help you achieve the best possible solution.
Sebastiaan Jansen | Manager Cooling Department
Sebastiaan Jansen has been working at Heinen & Hopman since 1997. He started as assistant mechanic at our company and worked his way up to the position of Manager Cooling Department. Sebastiaan and his team are responsible for the engineering of the cooling systems for all kinds of Heinen & Hopman projects. He aims to achieve the highest quality systems through applying innovative technologies. A challenging, but interesting, task.