To avoid the use and emissions of hydrofluorocarbons (HFCs), a variety of climate-friendly, energy-efficient, safe and proven alternatives are available.
Due to different thermodynamic and safety properties of the alternatives, there is no ‘one size fits all’ solution. The suitability of a certain alternative must be considered separately for each category of product and equipment; and in some cases also take into account the geographical location in which the product and equipment are used.
Why use alternatives?
The climate impact of a substance is commonly expressed as the global warming potential (GWP). The lower the GWP, the more climate-friendly the substance.
HFCs have a very high GWP and are hence potent greenhouse gases. Most of the HFCs are used as refrigerants in refrigeration and air conditioning (RAC) equipment, but also as blowing agents, aerosol propellants and solvents.
To mitigate emissions of substances with a high GWP and comply with the F-Gas Regulation, each sector needs to find solutions to quickly switch to low GWP refrigerants.
Alternatives and safety groups
Most of the HFCs are used as refrigerants in refrigeration and air conditioning (RAC) equipment, but also as blowing agents, aerosol propellants and solvents.
In the following, alternatives to commonly used HFCs are listed for different sectors.
The alternatives include
- Natural refrigerants
- HFCs with lower GWP, such as R32
- Hydrofluoroolefins (HFOs)
- HFC-HFO blends.
Each substance is assigned to a safety group specified as follows:
| Lower toxicity | Higher toxicity | |
|---|---|---|
| No flame propagation | A1 | B1 |
| Lower flammability | A2 | B2 |
| A2L* | B2L* | |
| Higher flammability | A3 | B3 |
Commercial refrigeration
Commercial refrigeration applications include stand-alone equipment, condensing units and centralised systems.
Plug-in equipment used in small stores and supermarkets, such as vending machines relying on hydrocarbons, has become available in recent years throughout the world. CO2-based systems have also been introduced.
In large refrigeration systems for supermarkets (’centralised systems’), CO2 cascade systems are an alternative to commonly used HFC systems in many climates.
The cascade refrigeration system is structured by connecting at least two refrigeration systems in series, with a higher-temperature side and a lower-temperature side. In these cycles different refrigerants are used, which have different freezing and boiling points. This is more efficient compared to conventional refrigeration systems.
Hydrocarbons have also proven to be highly efficient alternatives in most applications under high ambient temperatures, except for larger condensing units.
Centralised systems
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) R717 (ammonia) R744 (CO2) |
3 - 1 |
- - - |
A3 B2L A1 |
R134a, R404A, R407A R134a, R404A, R407A R134a, R404A, R407A |
| HFC-HFO blends | R448A R449A |
1387 1397 |
R32/125/1234yf/1234ze(E)/134a R32/125/1234yf/134a |
A1 A1 |
R404A R404A |
Condensing units
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) R744 (CO2) R717 (ammonia) |
3 1 - |
- - - |
A3 A1 B2L |
R134a, R404A, R407A R134a, R404A, R407A R134a, R404A, R407A |
| HFC-HFO blends | R448A R449A R452A* R454C R513A |
1387 1397 2140 148 631 |
R32/125/1234yf/1234ze(E)/134a R32/125/1234yf/134a R32/125/1234yf R32/1234yf R1234yf/134a |
A1 A1 A1 A2L A1 |
R404A R404A R404A R404A R134a |
Industrial refrigeration
In industrial refrigeration, such as large cooling facilities for food processing or process cooling in the chemical industry, ammonia systems have been used for many years.
Ammonia has been the most popular replacement option to R404A and its use is already widespread. In Europe, but also in other parts of the world such as North America, an increasing number of cascade systems with ammonia and CO2 have been installed in the food and beverage industry.
Industrial refrigeration
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) R717 (ammonia) R744 (CO2) R1270 (propene) |
3 - 1 2 |
- - - - |
A3 B2L A1 A3 |
R134a, R404A, R407A R134a, R404A, R407A R134a, R404A, R407A R134a, R404A, R407A |
| HFC-HFO blends | R449A R450A R513A |
1397 605 631 |
R32/125/1234yf/134a R1234ze(E)/134a R1234yf/134a |
A1 A1 A1 |
R404A R134a R134a |
| HFOs | R1233zd R1234ze |
4,5 7 |
- | A1 A2L |
R134a, R404A R134a, R404A |
Stationary air conditioning
Stationary air conditioning (AC) is designed to control the thermal comfort of living and working rooms. The stationary AC sector can be broken down into several sub-categories:
- Moveable room AC:
Devices that are hermetically sealed and can be moved between rooms by the user. Mostly used in private households. - Single split AC:
System that consists of one outdoor and one indoor unit linked by refrigerant piping, needing installation at the site of storage. Predominantly used in private households. - Multi split AC/VRF:
System that consists of one outdoor unit and multiple indoor units. Further developed systems enable a variable refrigerant flow (VRF) towards every indoor unit. Used in commercial facilities. - Chiller:
System in which the refrigerant cools down a liquid (normally water) that is then circulated to cool air in commercial or industrial facilities. - Heat pump:
System that is able to provide heating or cooling by transferring heat from or to an external reservoir (such as the ground, water or outside air). Used both in private households and commercial facilities.
In room air conditioning systems, hydrocarbons are safely used as alternative refrigerants in several countries such as India and China, but they are not yet common in the EU.
In chillers, hydrocarbons and ammonia are safe and energy-efficient alternatives to HFCs, both under moderate and high ambient temperature conditions. Heat pumps are also used with hydrocarbons, additionally CO2 is available on the market.
Moveable room AC
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) | 3 | - | A3 | R407A, R410A |
| HFCs | R32 | 675 | - | A2L | R407A, R410A |
Single split
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) | 3 | - | A3 | R407A, R410A |
| HFCs | R32 | 675 | - | A2L | R407A, R410A |
Multi split/Variable refrigerant flow (VRF)
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) | 3 | - | A3 | R407A, R410A |
| HFOs | R1234yf R1234ze |
4 7 |
- - |
A2L A2L |
R407A, R410A R407A, R410A |
| HFCs | R32 | 675 | - | A2L | R407A, R410A |
Chiller
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) R717 (ammonia) R718(H20) R744 (CO2) R1270 (propene) |
3 - - 1 2 |
- - - - - |
A3 2BL A1 A1 A3 |
R134a, R407A, R410A R134a, R407A, R410A R134a, R407A, R410A R134a, R407A, R410A R134a, R404A, R407A |
| HFC-HFO blends | R452B R454B R455A R513A |
698 466 148 631 |
R32/125/1234yf R32/1234yf R32/1234yf/CO2 R1234yf/134a |
A2L A2L A2L A1 |
R410A R410A R404A R134a |
| HFOs | R1233zd R1234ze |
4,5 7 |
- - |
A1 A2L |
R134a, R410A R134a, R407A, R410A |
| HFCs | R32 | 675 | - | A2L | R134a, R407A, R410A |
Heat pumps
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R290 (propane) R718 (H2O) R744 (CO2) |
3 - 1 |
- - - |
A3 A1 A1 |
R134a, R407A, R410A R134a, R407A, R410A R134a, R407A, R410A |
| HFC-HFO blends | R454C R513A |
148 631 |
R32/1234yf R1234yf/134a |
A2L A1 |
R410A R134a |
| HFCs | R32 | 675 | - | A2L | R134a, R407A, R410A |
Domestic refrigeration
In Europe, hydrocarbon refrigerants have replaced the use of HFCs since the mid-1990s.
Domestic refrigeration
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R600a (isobutane) | 3 | - | A3 | R134a |
Mobile air conditioning
The refrigerant R134a used in the air conditioning of cars is prohibited in new cars thanks to EU Directive 2006/40/EC on mobile air-conditioning systems (the ‘MAC Directive’).
The main substitute is the R1234yf, which is almost exclusively used. The only alternative to this is CO2, which is currently used by some car manufacturers and expected to become more widespread in the future.
CO2 is also expected to become available as an alternative in the future for duty vehicles, buses and trains.
Mobile air conditioning for cars
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R744 (CO2) | 1 | - | A1 | R134a |
| HFOs | R1234yf | 4 | - | A2L | R134a |
Mobile air conditioning for buses
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R744 (CO2) | 1 | - | A1 | R134a |
| HFC-HFO blends | R450A R513A |
605 631 |
R1234ze(E)/134a R1234yf/134a |
A1 A1 |
R134a R134a |
Mobile air conditioning for trains
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R729 (air) R744 (CO2) |
- 1 |
- - |
A1 A1 |
R134a R134a |
Transport refrigeration
Lately, R448A, R449A and R452A have become quite common to replace R404A in road transport refrigerated vehicles. R452A has a very high GWP of 2140 and hence will not be suitable for future use. For refrigerated containers, CO2 can be used as a long-term alternative.
Refrigerated vehicles
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R744 (CO2) | 1 | - | A1 | R134a, R404A, R410A |
| HFC-HFO blends | R448A R449A R452A |
1387 1397 2140 |
R32/125/1234yf/1234ze(E)/134a R32/125/1234yf/134a R32/125/1234yf |
A1 A1 A1 |
R404A R404A R404A |
Refrigerated containers
| Substance | GWP | Composition | Safety group | Replacement for | |
|---|---|---|---|---|---|
| Natural refrigerants | R744 (CO2) | 1 | - | A1 | R134a, R404A, R410A |
| HFC-HFO blends | R452A R513A |
2140 631 |
R32/125/1234yf R1234yf/134a |
A1 A1 |
R404a R134a |
Foam blowing
Polyurethane (PU) foam: Only few PU foam products are still manufactured with HFC blowing agents. The vast majority rely on hydrocarbons such as pentane or cyclo-pentane without loss in energy efficiency. HFCs are mainly limited to on-site application of PU spray foam. For this and some niche applications, unsaturated HFCs are already commercially available.
Extruded polystyrene (XPS): Major manufacturers of XPS insulation boards have already converted their production facilities to organic solvents or HFOs. The remaining users of HFCs are switching to HFOs. Energy efficiency of HFOs is considered to be better than that of HFCs.
Studies
A number of studies on the feasibility and availability of alternatives at sub-sectoral level have been carried out by various renown experts, including an extensive analysis carried out for the European Commission by the independent consultant Öko-Recherche in the context of developing Regulation (EU) No 517/2014.