Market Availability and Installation Data

This chapter examines the market availability of commercial chillers and heat pumps using natural refrigerants. Data on market availability was gathered from the websites and product brochures of manufacturers who sell their products in Europe. In total data was gathered on more than 300 products from more than 65 manufacturers. Note that these are estimated totals as of August 2026.

Market availability data is broken down into four equipment types: chillers, heat pumps, reversible heat pumps and four-pipe/polyvalent heat pumps. Note that the classification of products is based on how manufacturers advertise them on their websites and in their catalogs. This means that some products are counted in multiple categories if a manufacturer explicitly advertises them as such: for example a heat pump that is also available in a reversible or four-pipe configuration.

This chapter also provides estimates on the number of commercial natural refrigerant chillers and heat pumps installed in Europe (the installed base) as of December 2025. These estimates were informed by data gathered from manufacturers through surveys and interviews. In addition, desk research was also conducted, with data gathered from news articles, year-end financial and sustainability reports, and marketing material.

ATMOsphere found 131 commercial chillers using natural refrigerants available in Europe. These chillers were placed on the market by more than 40 different manufacturers. Propane (58.8%) and ammonia (33.6%) are the top refrigerants used, and there are more air-cooled chillers (68%) than water-cooled chillers (32%). Propane is the dominant refrigerant choice in air-cooled chillers (66%) while ammonia is the dominant refrigerant choice in water-cooled chillers (57%).

The infographics below show the coverage across the 30–400kW capacity range by refrigerant for both air- and water-cooled chillers. The entire range is well-served by natural refrigerants, with more than 50 models air-cooled chillers and 30 water-cooled chillers. Despite the flammability risk, propane is prominent throughout the capacity spectrum for water-cooled chillers in the lower and mid-tier range, with ammonia asserting itself at the higher end (300kW+).

Enex Technologies is the parent company of eight different HVAC&R equipment manufacturers, including several that specialize in natural refrigerant chillers and heat pumps. In 2022 it acquired the Emicon Group, which manufactured propane heat pumps and chillers.¹ That same year it acquired ammonia chiller manufacturer Samifi France,² and in 2023 it expanded its ammonia offerings with the acquisition of EOS Refrigeration, which produced ammonia heat pumps and chillers.³

Enex Technologies’ current product lineup includes low-charge air-cooled ammonia chillers, air-cooled and water-cooled propane chillers, and an air-cooled CO₂ chiller. It also offers air-to-water propane and air-to-water and water-to-water CO₂ heat pumps.

In August 2025 Massimiliano Sfragara, Enex Technologies’ Product Management Director, said the company was keeping an eye on trends in low-charge propane and ammonia chillers.⁴ The year before it presented the results of a simulation at the Data Center Nation event in Milan showing the energy efficiency of ammonia chillers in data center cooling applications.

Enex Technologies has been building commercial chillers and heat pumps for more than a decade. In 2017 it provided CO₂ chillers for Italian wineries used for process cooling and heating along with comfort cooling in offices.⁵ In 2022 four of its CO₂ heat pumps with a total capacity of 1.6MW (455TR) were installed at a hotel in Sicily and provided space heating, air-conditioning and domestic hot water.⁶

ATMOsphere found 44 commercial natural refrigerant-based heat pumps from 23 different manufacturers available in Europe. Unlike with chillers, there is a much higher diversity of refrigerants: propane (43.2%), CO₂ (36.4%), isobutane (13.6%) and ammonia (6.8%). The split between air-source and water-source heat pumps was 66% to 34%.

Propane (55%) and CO₂ (41%) are the top refrigerants for air-source heat pumps, and for water-source heat pumps the top refrigerants are isobutane (33%), CO₂ (26%) and ammonia (20%). The refrigerant mix for heat pumps is much more diverse than for chillers in general, although it becomes less so when split out among air-source and water-source heat pumps.

Notably, though, there are far fewer commercial heat pumps with natural refrigerants on the market (heating only) than chillers. While the entire 30–400kW capacity range is covered, it’s by only a few manufacturers and a relative handful of heat pumps.

When Mitsubishi Heavy Industries established a European office in London in 2013, very few companies were selling commercial CO₂ heat pumps.⁷ Despite this MHI saw an opportunity for the Q-ton, a CO₂ heat pump designed to produce domestic hot water in commercial buildings.

The Q-ton has a capacity of 30kW, and up to 16 units can be coupled together to increase its total heating capacity to 480kW (136TR).⁸ It can produce hot water at 90°C (194°F) in ambient temperatures as low as –25°C (–13°F).

The Q-ton quickly found a market. At ATMOsphere Europe 2015 MHI said it had installed Q-tons in an office block in Germany, hotels in Spain and the U.K., and a student residence in the U.K.⁹ The company said its sales grew by 40% between 2021 and 2022,¹⁰ and ATMOsphere estimates more than 100 Q-tons have been installed in Europe as of 2025.

More recently three Q-tons with a capacity of 90kW (25.5TR) were installed at a newly built Adagio Hotel in London to provide domestic hot water to its 140 rooms.¹¹ The hotel’s hot water system had to meet local regulations around carbon and NOx emissions along with Adagio’s own sustainability goals, which is why MHI’s CO₂ heat pumps were chosen.

ATMOsphere found 91 reversible commercial heat pumps using natural refrigerants from 37 different manufacturers available in Europe. Propane (97.8%) is the top refrigerant for this equipment type. The split between air-source and water-source is 74% to 26%.

All reversible air-source heat pumps in the database use propane refrigerant. Propane (86%) is also the dominant refrigerant among reversible water-source heat pumps.

The infographics below show the heating and cooling capacity ranges of the reversible heat pumps in the database. There are similar patterns between the two heat pump types. There are more air-source units in the lower capacity ranges than water-source units, and the number of heat pumps in each capacity band drops off sharply for both at the 150–200kW capacity band.

Enerblue built its first commercial CO₂ heat pump in 2012 and first propane chiller in 2013. Since then the company has gone on to sell more than 1,000 commercial propane chillers and heat pumps globally as of 2024.¹²

The first installation of an Enerblue propane system was in 2014 at a hotel in the Nordics, and as of 2024 more than 220 of its propane chillers and heat pumps were installed in the region, including six at the university of Oslo.¹³ In 2025 another Enerblue propane chiller was installed in Oslo as part of the net-zero retrofit of a Radisson hotel for comfort cooling.¹⁴

In 2025 four of the company’s air-to-water propane heat pumps were connected in cascade to provide 900kW (255TR) of space heating to a 27,000m2 (290,630ft2) railway maintenance hub in Europe.¹⁵ The heat pumps replaced a gas boiler and, in conjunction with existing solar panels and insulation upgrades, cut the facility’s annual CO₂e emissions by up to 90%.

In 2013 the Kratschmayer Gruppe, a German HVAC&R installer, began researching natural refrigerant chillers and heat pumps. The company commissioned its first propane chiller in 2016 and in 2018 it founded Skadec, which exclusively manufactures commercial propane and isobutane heat pumps and chillers.

Its units range in size from a compact water-cooled chiller with 13kW (3.6TR) of cooling capacity to an air-cooled chiller with 1.5MW (426TR) of cooling capacity. Skadec also manufactures several water-cooled chillers and water-source heat pumps, pushing back on the notion that flammable refrigerants can’t safely be used indoors. In July of 2025 the company said its most-popular products included four-pipe heat pumps for commercial applications, compact indoor chillers in cascade setups and systems specified with free cooling and heat recovery.¹⁶

Skadec’s propane products have been installed across Europe, with recent projects in Vienna and Norway.¹⁷ In Vienna an air-source Skadec propane heat pump offering simultaneous heating and cooling replaced the gas heating system at Vienna’s Austrian Museum of Folk Life and Folk Art. In Norway three Skadec reversible propane heat pumps provide 1.4MW (398TR) of heating and 970kW (275TR) of cooling at a retail shopping center.

ATMOsphere found 41 commercial natural refrigerant-based four-pipe/polyvalent heat pumps from 24 different manufacturers available in Europe. This equipment type is split between three refrigerants: CO₂ (56.1%), propane (36.6%) and ammonia (7.3%). The split between air-source and water-source is 65% to 35%.

There is a split between propane (51%) and CO₂ (48%) for air-source four-pipe/polyvalent heat pumps. For water-source four-pipe/polyvalent heat pumps the refrigerant mix is: CO₂ (71%), ammonia (21%) and propane (7%).

For air-source four-pipe/polyvalent heat pumps CO₂ and propane are present across the capacity spectrum. The majority of cooling and heating capacity is on the lower-to-middle part of the spectrum from 50–250kW. Ammonia joins CO₂ and propane in the refrigerant mix for water-to-water four-pipe/polyvalent heat pumps, albeit in small numbers, with this equipment category made up primarily of systems using R744. However, like with heat pumps, the total sample size is small relative to other equipment types mentioned in this chapter.

At Chillventa 2024, Italian manufacturer Euroklimat announced that it had sold more than 3,000 commercial propane chillers and heat pumps in Europe in total.¹⁸ The company began manufacturing propane chillers in 2006 and today it offers a full range of R290 air-cooled chillers with capacity ranges from 30‒1,000kW (8.5‒284TR).

Euroklimat built its first propane heat pump in 2018, which debuted at that year’s Chillventa. Today it manufactures air-to-water heat pumps and water-to-water heat pumps – both reversible and four-pipe/polyvalent units – with capacity ranges from 30‒700kW (8.5‒199TR). Michele Bedin, CEO of Euroklimat, said in 2024 that the company has not had a problem or accident involving one of its propane products.

End users of Euroklimat’s propane chillers and heat pumps in Europe include cheese producers, pharmaceutical companies and supermarkets.¹⁹ In 2024 Celine Lach, President of the CTA Group, the parent company of Euroklimat, presented a case study of a Euroklimat propane heat pump used at a Heineken production facility in Puglia, Italy.²⁰

The beer manufacturer previously used a gas boiler and city water to meet the simultaneous heating and cooling demand of a pasteurization tunnel. A Euroklimat four-pipe water-to-water propane heat pump with a heating capacity of 185kW (52.6TR) and a cooling capacity of 135kW (38.3TR) was installed. Hot water is produced at 70°C (158°F) and cold water at 26°C (78°F), and the unit has a COP of 3.77. The heat pump draws 55% of its power from a rooftop array of solar panels, which has helped Heineken reduce the energy consumption of its pasteurization tunnel by 75%.

As of December 2025 ATMOsphere estimates there were 27,000 commercial propane chillers and heat pumps and 1,000 commercial CO₂ chillers and heat pumps installed in Europe. Combined these figures represent fewer than 5% of the total installed base of commercial chillers and heat pumps in Europe. Data could not be gathered for ammonia commercial chillers and heat pumps.

As propane and synthetic chillers share similar operating pressures, thermodynamic behaviors and components, R290 has thus become the go-to natural alternative in commercial chillers, especially in process cooling. The high-temperature heat recovery capabilities of CO₂ have made it a fit in integrated HVAC systems, and R744 has also established itself in commercial hot water heat pumps.

While propane and CO₂ commercial chillers and heat pumps have been on the market for more than a decade, the market conditions required to stoke their growth have only been present for a few years. The installed base of commercial natural refrigerant chillers and heat pumps should expand in the coming years as manufacturers seek future-proof and efficient equipment to replace aging HFC-based systems.