Air conditioning and refrigeration are part of our daily life more than we think: air conditioning, refrigerators, freezers, heat pumps, industrial systems… All of them work thanks to a key element that we rarely see, but that has a huge environmental impact: the refrigerant.
For decades, traditional refrigerant gases have been highly polluting, with a high global warming potential and an important role in the deterioration of the ozone layer. Therefore, talking today about ecological refrigerants is not a fad or a passing tendency, but an urgent necessity within the path towards a more sustainable energy model. That said, let us see what ecological refrigerants are, what types exist and which is the least polluting for the future.
What are ecological refrigerants?
Ecological refrigerants are substances used in refrigeration and air conditioning systems that stand out for having a much lower environmental impact than traditional refrigerants. For a refrigerant gas to be considered ecological, it must mainly meet these criteria:
- Low or zero Global Warming Potential (GWP)
- Zero impact on the ozone layer (ODP = 0)
- High energy efficiency
- Greater compatibility with current and future environmental regulations
Unlike conventional fluorinated refrigerants, many ecological refrigerants are natural substances or compounds with a very short atmospheric life, which significantly reduces their contribution to climate change. Therefore, when we talk about ecological refrigerant gas, we not only refer to its origin, but to its long term environmental behavior.
Types of ecological refrigerants
Ammonia (R717)
Ammonia is one of the oldest refrigerants and, paradoxically, one of the most ecological. It has a practically zero GWP, the ODP is 0 and it has excellent energy efficiency. R717 is used mainly in industrial refrigeration and large installations, since it is toxic in high concentrations and requires well designed systems and specialized personnel. Despite this, from an environmental point of view, it is one of the most sustainable refrigerants that exist.
Carbon dioxide (R744)
CO2 as a refrigerant can be surprising, but it is one of the most interesting options within ecological refrigerants. Its advantages:
- GWP = 1 (minimum possible reference)
- Does not damage the ozone layer
- Is not flammable
- Very abundant and economical
R744 is increasingly used in supermarkets, refrigerated transport and modern air conditioning systems. Although it works at higher pressures, its environmental impact is very low, making it a key ecological refrigerant gas.
Hydrocarbons (propane R290 and Isobutane R600a)
These are the most important in terms of new ecological refrigerants. The most used are propane (R290) and isobutane (R600a). It has an extremely low GWP and its ODP is zero, being very energy efficient and with excellent thermodynamic behavior.
The main disadvantage is that they are flammable, which requires safe designs, strict regulations and controlled amounts of refrigerant in each equipment. Even so, its use is growing exponentially in both domestic refrigeration and air conditioning.
Water
Water can also act as a refrigerant in certain specific applications, since it is neither toxic nor flammable, obviously. However, its use is limited to very specific systems due to its physical properties. Even so, it represents the absolute ideal from an environmental point of view.
The new R290 ecological refrigerants
Among the new ecological refrigerants, R290 (propane) is one of the best, being something perfect for modern air conditioning and refrigeration. Although flammable, they are quite efficient, in fact it is something that is managed through:
- More safe equipment designs
- Limited amounts of refrigerant
- Very strict technical regulations
In return, its energy efficiency is superior to many traditional refrigerants, reduces electricity consumption with minimal environmental impact and has excellent performance even in demanding climates. For all these reasons, R290 is considered one of the ecological refrigerants with the greatest future projection, especially in heat pumps and domestic air conditioning.
Advantages of natural refrigerants for the future
The transition towards ecological refrigerants not only responds to an environmental issue, but also to economic, regulatory and energy reasons. Among its main advantages stand out:
- Drastic reduction of greenhouse gas emissions
- Compliance with European regulations and international agreements
- Greater energy efficiency and lower consumption
- Systems more prepared for the future
- Less dependence on complex synthetic refrigerants
Which is the least polluting refrigerant?
This is something that requires clarification, because it depends on the context and the application we are going to give it. From a purely environmental point of view:
- Water and ammonia are the least polluting refrigerants
- CO2 (R744) stands out for its balance between safety and environmental impact
- Propane (R290) is like one of the best options for domestic use
In practice, the least polluting refrigerant is that which has the lowest possible GWP, that adapts correctly to the installation and that offers you maximum energy efficiency. Therefore, ecological refrigerants not only represent the future, but are already the present of a cleaner, more efficient and responsible air conditioning.
