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Sonia Saini

The European Commission has released a proposed regulation that would establish minimum requirements for certification programs for engineers working with natural refrigerants – specifically CO2 (R744), hydrocarbons and ammonia (R717) – and f-gases, as mandated by the recently revised EU F-gas Regulation.

The scope: Under the proposal, a certificate would be required to conduct leak checks, install equipment and to repair, service and decommission equipment using fluorinated or natural refrigerants, the latter of which are referred to as “alternatives” or “alternative substances” by the Commission.

  • The equipment covered includes stationary refrigeration, air-conditioning and heat pumps.
  • Organic Rankine cycles, refrigeration units in refrigerated trucks and refrigerated trailers, and refrigeration units of refrigerated light-duty vehicles, intermodal containers and train wagons are also included in the proposal.
  • The regulation would also apply to third parties that install, repair, maintain or decommission equipment using f-gases or natural refrigerants. Equipment manufacturers would not be subject to the regulation provided manufacturing, repairing or “related activities” are done “at the site of the manufacturer.”

Individual certificates: Under the proposal, five certificate types would be created. EU member states would be allowed to issue individual or combined certificates specifying the specific activities covered:

  • Certificate A: required to work with f-gases or hydrocarbons
  • Certificate B: required to work with CO2
  • Certificate C: required to work with ammonia
  • Certificate D: required to work with equipment containing less than 1kg (2.2lbs) of f-gases
  • Certificate E: required to do work on f-gas equipment that does not require “breaking into the refrigeration circuit”

Course content: The Commission has proposed that, to earn a certificate, applicants must pass practical and theoretical examinations organized by an “independent” and “impartial” certification body. Exams can also be organized by an “evaluation body” designated by the certification entity.

  • The annex to the proposal lays out the exam content, which is grouped into 14 categories and classified as being part of the theoretical or practical test.
  • All certificate types will feature theoretical and practical questions from the same seven categories, which include the environmental impact of refrigerants and relevant environmental regulation, information on relevant technologies to replace or to reduce the use of fluorinated greenhouse gases and their safe handling, and checks for leakage.
  • Those seeking certificates to work with natural refrigerants will be required to answer test questions from refrigerant-specific categories.
  • In addition, those seeking Certificate A will have to answer at least two questions related to the specifics of natural refrigerants and the energy efficiency of natural refrigerant equipment and complete at least one practical exercise involving natural refrigerants.

Feedback period: The EU Commission is soliciting public comments on the proposed regulation, which can be made until June 10 at 11:59 pm CET.

ATMOsphere’s involvement: ATMOsphere, the publisher of, advocated for mandatory training and certification on natural refrigerants alongside the Clean Cooling Coalition (CCC) during the recent revision process of the EU f-gas law. CCC is composed of European HVAC&R companies that view the rapid reduction of fluorinated substances as crucial to achieving the EU’s carbon-neutrality targets by 2050 and ensuring a high level of environmental protection.

The Ville-la-Grand Leclerc serves as the Irish OEM’s real-world showroom for its LEAP lineup of propane chest freezers and cabinets.
Sonia Saini

To shoppers at the bustling E.Leclerc hypermarket in the small French town of Ville-la-Grand, located on the Swiss border near Geneva, April 11 was just another spring day. However, for the leadership team at Irish commercial refrigerator manufacturer Novum, which was walking through the frozen and refrigerated food sections, the day was anything but ordinary.

Novum’s leadership team, including its CEO, CTO, CMO and Head of Sales, had gathered at the Ville-la-Grand Leclerc to celebrate a major milestone: the grand opening of what is, in effect, a real-world European showroom for its self-contained LEAP lineup of propane (R290) freezers and refrigerators. The Irish OEM’s leadership team was joined by affiliated contractors, distributors and the store’s director, Antoine Magré. was also on hand for the event.

Although the ribbon-cutting ceremony was scheduled for April, Novum’s real-world showroom actually opened in mid-January when 30 of its Grand Cayman chest freezers, 184 doors’ worth of Panama Green cabinets and five end-of-aisle displays were installed. All of the store’s chest freezers and 30% of its refrigerated cabinets are now served by Novum’s LEAP lineup, according to CTO Eoin Lennon. Of those cabinets, 80% contain refrigerated food, and 20% contain frozen food.

It’s an impressive display of product, though for Novum it’s not merely the number of units but what they’ve accomplished, specifically the cabinets, that’s notable. The 184 doors of self-contained upright cabinets installed at the Ville-la-Grand Leclerc replaced 30% of the remote CO2 (R744) units, which also were split 80/20 between refrigerated and frozen food.

Novum R290 cabinets in a frozen food aisle at the Ville-la-Grand E.Leclerc.
Novum R290 cabinets in a frozen food aisle at the Ville-la-Grand E.Leclerc. Photo credit:

“We haven’t had this before, somebody moving to LEAP technology from a CO2 system,” Novum CEO Jim Greene told “That’s taking it to another level. This is a first for us.”

Novum bills LEAP as “the only viable, scalable alternative to CO2 systems,” and the Ville-la-Grand Leclerc is its opportunity to show supermarket owners that’s more than a marketing slogan.

Taking the LEAP 

Magré was very interested in finding alternatives to CO2 for his store. He told that maintenance on the store’s CO2 refrigeration system – which was installed in 2017 – was “a major issue.” 

“We wanted something easier to use that we could manage with our internal capabilities and not be too dependent on the companies that service the remote systems,” Magré said. “They’re struggling with staffing issues, which is a general theme across France.”

Novum’s LEAP cabinets and chest freezers use the same hermetically self-contained cassettes consisting of a compressor, condenser, evaporator and evaporator fan. The cassette is located at the base of the chest freezers and on top of the upright refrigerators, which are available in two- and three-door configurations, with each door utilizing a separate cassette.

The cassettes of the Panama Green upright cabinets.
The cassettes on top of Novum’s R290 cabinets. Photo credit:

Each cassette comes pre-charged with 65g (2.3oz) of R290, and maintenance consists of swapping out one cassette for another.

Along with simpler servicing, the store has also seen its energy consumption dip since installing Novum’s LEAP cabinets and freezers. Magré told that the store’s energy consumption has been reduced by 15% since Novum’s products were installed in mid-January. Per Novum, that represents a 45% reduction in refrigeration energy consumption.

Energy savings 

Magré noted that the reduction in energy consumption can partially be owed to the fact that, unlike the refrigerated CO2 cabinets they replaced, Novum’s cabinets come equipped with doors.

Novum’s CTO concurred with that assessment, saying that the energy level “per door” of Novum’s cabinets is “class leading.” However, he further highlighted that addition by subtraction is also at play. 

“By replacing 30% of [Magré’s] chilled product cabinets with ours, he has taken that load off the CO2 plant,” Lennon said. “Less of [the CO2 compressors] are running on average than previously. As a result I believe he’s staying within the subcritical point more often. That’s making his CO2 refrigeration more efficient.”

Novum’s upright cabinets release heat directly into the store, and given this, it’s fair to wonder if the Ville-la-Grand Leclerc will see a rebound in energy consumption during the summer months. According to Lennon, the efficiency of the Novum LEAP line means that its freezers and cabinets won’t require the air-conditioning to be cranked up in summer.

“Simple physics comes into play here: energy in equals energy out,” said Lennon. “The more efficient you make a cabinet, the less heat energy it puts out.”

“There are no big heat emissions, which was one of our major worries,” Magré added.

According to Novum, its cabinets have a third of the heat rejection and energy consumption of similarly sized cabinets, and its chest freezer has 37% less heat rejection compared to its “next best-in-class competitor.”

Novum CTO Eoin Lennon
Novum CTO Eoin Lennon. Photo credit:

“It’s a combination of things,” said Lennon. “It’s the defrost, the evaporator location [outside of the main unit] and the airflow system design. The entire body of the cabinet is formed as one piece, so there’s no thermal bridging, and the doorframe technology reduces rail heating requirements.”

Lennon said that Novum also has a deep relationship with its controller provider, which has enabled the company to work with it to design bespoke controllers for the LEAP lineup to further optimize its energy efficiency.

Rumors vs. reality 

While the Ville-la-Grand Leclerc shows what Novum’s LEAP lineup is capable of, the company faces an uphill battle in convincing end users that its products can be an alternative to CO2 refrigeration systems. Self-contained R290 cabinets are not uncommon in Europe and are becoming more common in the United States, but they’re viewed as solutions for stores with smaller footprints, not hypermarkets.

Magré alluded to this, telling that he heard “rumors” in the “supermarket world” and from cooler-cabinet companies about problems moving from remote to self-contained cabinets.

“A lot of [cooler companies] came to see us and said, ‘Why did you do this? This is a major mistake,’” said Magré. “I think a lot of them are stuck on past issues, like those with electrical systems, which have been long resolved. We didn’t make a mistake, and we’re seeing this today.”

“We haven’t had this before, somebody moving to LEAP technology from a CO2 system. That’s taking it to another level. This is a first for us.”

Jim Greene, Novum CEO

Curated News With Commentary
Source: Canary Media

Why heat-pump water heaters could soon take off

Why It Matters: The Biden Administration has just announced new efficiency standards for electric water heaters that will take effect in 2029 in the U.S. That, combined with federal and state rebate and incentive programs, will supercharge the adoption of heat pump water heaters. But what’s not covered in this article is the refrigerant side. We are starting to see CO2 (R744)-based heat pump water heaters at the residential and commercial level, as well as the advent of ammonia absorption heat pumps that deliver domestic hot water and space heating. And by 2029 the U.S. should be ready for propane (R290)-based monobloc heat pumps that can also handle both space and water heating.
Moving from a diesel water heater to a CO2 heat pump could also reduce emissions at the hotel, located in Chennai, by 80%.
Sonia Saini

A new study has found that a hotel in Chennai, India, could cut its annual operating costs and CO2 emissions by 93% and 80%, respectively, by replacing its diesel-fired water heaters with CO2 (R744) water-source heat pumps paired with thermal storage tanks (TST).

An unnamed hotel equipped with a diesel water heater provided the data for the study, with the authors noting that fossil fuel water heating equipment is the norm for hotels in India, with very few using heat pumps.

The study proposes a new approach: using water from the hotel’s air-conditioning system’s chiller as the heat source to enhance overall efficiency. The water from the chiller enters the evaporator at 12°C (53.6°F) and exits at 7°C (44.6°C), providing heat for the liquid refrigerant inside.

The study, “CO2 Heat Pump Integrated Thermal Storage for Domestic Hot Water in Hotels,” was written by a team of researchers, including M.P. Maiya, a Professor at the Indian Institute of Technology Madras, and Armin Hafner, a Professor at the Norwegian University of Science and Technology (NTNU), and published in the Journal of Building Engineering. The study is part of the INDEE+ project, an Indo-Norwegian initiative funded by the Norwegian Ministry of Foreign affairs to support India’s transition to natural refrigerants.

The researchers evaluated various configurations of CO2  heat pumps, including simple system and ejector-assisted setups with or without an internal heat exchanger (IHX). The study concluded that an ejector-assisted CO2  heat pump system without an IHX, combined with a large TST, offers the most economical solution for continuous operation in hotel applications.

Heat pump, TST sizing

In the Chennai hotel’s current setup, two diesel-fired water heaters produce primary hot water at 65–70°C (149–158°F). The primary hot water transfers heat to secondary water stored in two tanks, which is used in the 200 guest rooms and hotel kitchen. The daily domestic hot water consumption for the hotel averages around 40,000L (10,566gal).

“If the heat pump is designed based on peak heat demand, the heating capacity [would be] nearly 140kW (39.8TR) at a gas cooler water inlet temperature of 25°C (77°F), with the heat pump operating almost eight hours per day,” the study said. “During peak hours, the heat pump can serve the required demand, and surplus hot water can be stored during non-peak hours.”

The study found that with round-the-clock operation, the optimum heat pump size becomes 50kW (14.2TR). For this optimum capacity, a 9,000L (2,377gal) TST would be required to fulfill the hotel’s demand at a gas cooler water inlet temperature of 25°C (77°F) and outlet temperature of 50°C (122°F).

“A low-capacity heat pump demands a higher-capacity TST,” the study said. “However, considerable investment costs can be reduced with this integrated system.”

A rapid ROI

According to the study, a return on investment is possible in less than two years despite the higher upfront equipment costs due to India’s low demand for CO2  systems. The study noted that the relatively short ROI is due to a combination of the CO2  heat pump’s higher energy efficiency and because it makes the air-conditioning system more efficient by using its chilled water as a heat source.

While the main comparison was to diesel water heaters, the study also found that a CO2 heat pump paired with a chiller offered a lower operating cost than a liquefied petroleum gas heater, natural gas heater and hydrogen water heaters.

The OC of the CO2 heat pump and chiller combination was also compared to an R134a heat pump, and it outperformed it until the water inlet temperature was raised to 35°C (95°F). The study notes that the annual average water temperature in tropical Chennai is 28°C (82°F), while in northern cities such as Delhi it averages 20°C (68°F). 

Based on its findings, the study recommended that the CO2 heat pumps be installed in hotels in Chennai, Delhi and Goa. Goa was the site of a recent INDEE+ workshop on decarbonizing hotels using CO2 heat pumps and chillers.

“During peak hours, the heat pump can serve the required demand, and surplus hot water can be stored during non-peak hours.”

Hafner et. al

The York YAS units, with capacities over 300kW, received approval from the state’s Resources, Safety and Health statutory board.
Sonia Saini

Johnson Controls (JC) has announced that it has received a “first-of-its-kind” compliance certification from the Australian Queensland Resources, Safety and Health (RSH) statutory board for its York-brand YAS large-scale propane (R290) chillers and air-to-water heat pumps.

According to a company brochure, the air-cooled YAS MC-VB chiller has a cooling capacity of 31.8–353kW (9–100TR) with a refrigerant charge ranging from 4–24kg (8.8–53lbs). The YAS RC-WP heat pump, also air cooled, has a cooling capacity of 90.9–297kW (25.8–84TR) with a refrigerant charge ranging from 13–57kg (28.7–126lbs). York reports energy efficiency ratios (EERs) for the units ranging from 2.4 to 3.3 based on the model and size. Both units use reciprocating compressors.

“The certification process involved rigorous testing and compliance measures, [with the] appliances using hydrocarbon refrigerants requiring additional certification,” JC said. “Approvals granted through this process are recognized throughout Australia, New Zealand and in some cases, internationally.”

The standards: According to a Johnson Controls Asia Pacific LinkedIn post, the units comply with the AS5149.2, IEC60079-15 and IEC60204-1 standards.

  • Terry Presley, Regional Manager Pacific, Industrial Refrigeration at JC, writes on LinkedIn that the first approved JC chiller will be installed at “a large retail shopping center” in the coming months.

YAS specifications: The YAS R290 chillers and heat pumps are designed for large-scale commercial and industrial applications and offer low-GWP solutions for state of Queensland’s retail outlets and food and beverage processing operations.

  • The YAS chiller line offers fluid leaving temperatures as low as −2°C (28.4°F) for medium-temperature applications and as low as −14°C (6.8°F) in the low-temperature model.
  • “Our MC VB models excel in refrigeration applications, such as producing low-temperature glycol for food and beverage cooling,” JC said.
  • The YAS heat pump “seamlessly” transitions between heating and cooling, providing water at temperatures up to 55°C (131°F) and glycol at temperatures down to −5°C (23°F), with a cooling capacity of 91‒297kW (26‒84TR).

NatRefs down under: Natural refrigeration solutions continue to gain popularity in the Australian market.

  • Supermarket Woolworths, with 1,095 stores in Australia, recently opened its 100th store with a transcritical CO2 refrigeration system in Wollongong, New South Wales. The company opened its first such store seven years ago.
  • A Coles supermarket in Howrah, Tasmania, opened in August 2022 with a CO2 heat pump providing store heating and an R290 chiller providing air-conditioning.
  • In 2022, Nightingale Housing, a non-profit apartment developer, announced it had installed 11 CO2 heat pumps built by Japanese OEM ITOMIC in six of its buildings, which provide space heating and hot water.
  • Also in 2022, SCM REF Australia, Beijer Ref Australia’s manufacturing operation, reported it had installed more than 220 transcritical CO2 units in Australia and New Zealand. At that time, Inderpal Saund, Business Development Manager APAC & Sales Manager at SCM REF Australia, said retailers were largely driving the market and that he expected to have 1,000 units sold by 2025.

Quotable: “Johnson Controls makes sure its products comply to relevant local standards and can be safely installed and operated,” Rickey Du, Product and Technology Manager, Industrial Refrigeration at Johnson Controls, told “We have taken a careful, comprehensive process in engineering, validation and compliance checks to make sure standards are all well met. While Johnson Controls sells these products in other countries, there have been engineering changes made for Australia standards compliance.”

The company said its CO2 condensing units will also be available in the coming months.
Sonia Saini

Europe-based Carrier Commercial Refrigeration (CCR), part of the Carrier Global Corporation, has announced that its CO2 (R744) compressor racks and heat pumps for refrigeration systems are now available in North America.

CCR said it is “offering its technology to a wide range of verticals” and that it is strongly focusing on industrial applications as well as food and grocery retail and convenience stores. In addition to racks and heat pumps, the company said it will also offer CO2 condensing units in the coming months.

“We’re energized and eager to bring this innovative technology to North America to help create a more sustainable future for people and our planet,” said Jimmy Washington, North America Managing Director at CCR.

CCR said it will leverage its “extensive industry experience and know-how” to support its new North American customers. The expansion into the new market falls on the heels of last December’s agreement by the U.S.-based Carrier Group to sell CCR to Haier Smart Home, a division of Chinese manufacturer Haier. The sale is expected to close in the second half of 2024.

“The acquisition will help enable the company to capture additional growth opportunities by expanding its presence to food retail refrigeration and cold storage,” said Li Huagang, Chairman and CEO of Haier Smart Home, when the sale was announced.

The U.S. market for natural refrigeration systems, including transcritical CO2, is primed for growth. The U.S. Environmental Protection Agency – as mandated by the American Innovation and Manufacturing (AIM) Act – has set a GWP limit of 150 for many types of new refrigeration equipment used in supermarkets and industrial facilities. Compliance dates start next year.

According to ATMOsphere’s 2023 Natural Refrigerants: State of the Industry report (p. 95), only 4.09% of all U.S. and Canadian grocery stores and supermarkets use transcritical CO2 systems. ATMOsphere is the publisher of

Transcritical CO2 is also used at just 498 industrial sites. While the report did not contain data on CO2 condensing units, it did note that interest in them is growing among North American supermarkets. In March, U.S.-based OEM Zero Zone launched a transcritical CO2 condensing unit designed for supermarkets and small industrial applications. In 2022, another U.S. manufacturer, Hillphoenix, released a CO2 condensing unit designed to serve both store cold rooms and cabinets.

CO2 product range

Carrier says that the knowledge gained from installing its first transcritical CO2 system in 2004 in a Swiss hypermarket helped in the development of CCR’s CO2OLtec line, which it launched in 2009.

Today, the company offers a variety of customized solutions for transcritical CO2 racks and heat pumps, with specific design focuses ranging from energy efficiency to temperature control, CCR explained. Heat recovery and patented ejector technology provide additional operational energy savings.

For medium-to-large supermarkets, CCR offers its MiniCO2OL and MiniCO2OL Compact, with medium-temperature (MT) refrigeration capacities from 40‒380kW (11‒108TR) and low-temperature (LT) capacities from 0‒110kW (0‒31TR).

The MaxiCO2OL offers refrigeration capacities from 200‒550kW (57‒156TR) MT and 0‒360kW (0‒102TR) LT for medium-to-large supermarkets and warehouses.

To increase energy efficiency, CCR offers its CO2OLtec Evo with a modulating ejector added to its Mini or MaxiCO2OL units to increase the cooling capacity range to 60‒660kW (17‒188TR) MT and 0‒450kW (128TR) LT. According to the company, adding the ejector provides a 20% energy savings.

The company’s PowerCO2OL compressor rack for industrial applications provides up to 1,500kW (427TR) MT and up to 500kW (142TR) LT refrigeration capacities.

CO2 heat pump/chiller solutions provided by CCR include the HeatCO2OL Commercial, with heating capacities up to 230kW (65TR) at 90°C (194°F), and the HeatCO2OL Industrial with heating capacities up to 2,200kW (626TR) at 90°C.

CCR’s packaged CO2 condensing units cover small store formats to warehouse applications and include:

  • QuietCO2OL, with 0.8‒9.1kW MT (0.2‒2.6TR) and 0.7‒6.5kW (0.2‒1.8TR) LT capacities
  • QuietCO2OL MC Indoor/Outdoor, with 2‒93.2kW (0.6‒26.5TR) MT and 2‒17.3kW (0.6‒4.9TR) LT capacities
  • MiniCO2OL Outdoor, with 50‒160kW (14.2‒45.5TR) MT and 5‒67kW (1.4‒19TR) LT capacities
  • GC5 CO2 Large Outdoor, with 60-380kW (17‒108TR) MT and 8‒170kW (2.3‒48.3TR) LT capacities

CCR recently announced the release of a new CO2 efficiency booster skid, dubbed the CO2OLtec EB. When added to a transcritical rack, the company said it reduces energy consumption by up to 10% compared to conventional CO2 booster systems. As an add-on, the unit comes in four models for MT applications and three for LT.

“We’re energized and eager to bring this innovative technology to North America to help create a more sustainable future for people and our planet.”

Jimmy Washington, North America MD at CCR

Why It Matters: Pascal Raises $8M in Seed Funding

Boston-based startup Pascal has raised $8 million in seed funding to “productize” the development of its low-pressure solid-refrigerant technology for the commercial HVAC&R sector. Using a “new class” of solid materials it discovered, the company said its tech transfers heat via a low-pressure solid-solid phase change. Pascal has hydrofluorocarbons in its sights and says its tech – which can be used in heat pumps, air conditioners, refrigerators and freezers – offers zero emissions and is 50–80% more energy efficient compared to HFC-based systems.

Original post link: Pascal Raises $8M in Seed Funding


Sonia Saini

U.S.-based OEM Copeland has announced a £19 million (€22.1 million/$23.9 million) investment in its compressor manufacturing facility in Cookstown, Northern Ireland, which it said will increase production capacity to “meet the European demand for sustainable, low-carbon heat pumps.”

The expansion: Copeland said the investment includes a 3,500m2 (37,673ft2) building expansion that will add new product lines and give it the ability to increase production while providing the “flexibility” to meet future demand.

  • Copeland said the building expansion has already begun and that it is anticipated to be completed by September 2024.
  • Since opening in 1997, the Cookstown plant has produced more than 5 million Copeland compressors.

NatRefs at Cookstown: While Copeland did not specify that the expansion was to produce compressors for heat pumps using natural refrigerants ( has reached out for clarification) its Northern Ireland plant has a history with both propane (R290) and CO2 (R744) compressors.

  • Per Copeland, the Cookstown plant built its first R290 and low-sound compressors, including a propane scroll compressor for commercial and domestic heat pumps released this past December that it called the “most silent scroll compressor for domestic use.”
  • The company said Cookstown also “took the lead” in developing its first transcritical CO2 compressors for refrigeration systems.

Against the grain: Copeland’s bullishness on the European heat pump market, specifically “sustainable, low-carbon” heat pumps, stands in stark contrast to recent stances taken by industry stakeholders.

  • NIBE Group, the parent company of heat pump manufacturer NIBE, recently announced it will lay off 340 employees due to “much weaker demand” in the European heat pump market. NIBE manufactures both R290 and HFC heat pumps.
  • The European Heat Pump Association (EHPA) said heat pump sales in 14 European countries decreased by 5% in 2023 compared to 2022. The report did not group heat pumps by refrigerant types, though, and the EHPA has previously said the revised EU F-gas regulation, which recently became law and mandates a phase out of HFCs by 2050, would “slam the brakes on heat pump deployment.”
  • Copeland is optimistic about the future of air-to-water residential heat pumps in Europe and forecasts 4.1 million installations by 2030. Copeland’s optimism is backed by European manufacutrers, which have  shown a particular interest in producing new hydronic R290 residential monobloc units in recent years.

Quotable: “Our Cookstown site, and our colleagues who work there, play a critical role in helping Copeland develop and produce products and technologies that contribute to decarbonization and the protection of the environment,” said CEO Ross B. Shuster. “This new investment in Cookstown will allow us to best serve Europe’s anticipated demand for heat pumps and sustainable air-conditioning technologies, which are crucial for supporting the U.K. and European Union’s decarbonization goals.”

The funding will go to three residential heat pump development projects under its Heat Pump Ready initiative.
Sonia Saini

The U.K. government has announced £1.77 million (€2.06 million/$2.22 million) in funding for three natural refrigerant-based heat pump projects under its Heat Pump Ready initiative.

The Flexible Heat Pump from Clear Blue Energy, Natural Heat from FeTu and Cube X from Mixergy were the natural refrigerant projects funded. The grants are part of a larger £5.3 million (€6.2 million/$6.6 million) investment in heat pump R&D, which is split across nine projects.

According to the U.K. Department for Business, Energy and Industrial Strategy (BEIS) and Department for Energy Security and Net Zero (DESNZ), the funding is designed to support efforts to reduce the lifetime cost of residential heat pumps and improve consumer perception and experience through the development of technologies, tools and business models.

One of the main objectives of the program is to develop solutions that help position heat pumps as the technology of choice for British consumers, particularly in “distress purchase situations,” when a new domestic heating system is required urgently.

Another focus is to develop energy- and cost-efficient solutions that use low-GWP (<150) refrigerants. With 20-year GWPs of 1 or below, natural refrigerants like CO2 (R744) and propane (R290) offer future-proof options for heat pump technologies.

The nine projects were selected following an application process that began in October 2023. Up to £10 million (€11.6 million/$12.5 million) was available for allocation.

The recipients

Clear Blue Energy has received a grant of £773,156 (€899,543/$971,288) to develop a prototype of its R290 Flexible Heat Pump in partnership with Sourcethermal, the University of Liverpool and Pragmatic Energy. The air-source unit provides both space heating and domestic hot water, with the ability to efficiently deliver high temperature lift, Adrian Richardson, Director of Clear Blue Energy, told

“[The] initial focus is on a range of residential applications and output capacities,” he said. “We expect the incremental benefit over conventional heat pumps will be higher in larger capacities, so will also look at industrial and commercial applications of our technology in due course.”

According to the collaborative, the Flexible Heat Pump outperforms conventional heat pump technologies with a “higher cycle efficiency” due to the inclusion of a heat storage device that can recover, store and reuse part of the sensible heat carried by the hot liquid refrigerant from the condenser. In addition to acting as a secondary heat source and enabling more efficient defrost cycles, this technology boosts system COP to “significantly lower running costs.”

“We expect the incremental benefit over conventional heat pumps will be higher in larger capacities, so will also look at industrial and commercial applications of our technology in due course.”

Adrian Richardson, Clear Blue Energy

FeTu has received £465,763 (€541,901/$585,121) for the development of its natural refrigerant-based heat pump, Natural Heat. While the refrigerant used is not specified, the company does have experience in CO2-based refrigeration and heat pump applications. has contacted FeTu for clarification.

The unit will use FeTu’s novel compressor, which offers high levels of volumetric and thermal efficiency. The funding will support the company’s design, manufacturing, assembly and testing efforts over the coming year.

Mixergy and Harlequin Manufacturing have been awarded £530,080 (€616,732/$665,920) for their CubeX heat pump. Mixergy has not specified the refrigerant used in its CubeX heat pump; however the company does produce an R290-based integrated heat pump cylinder for hot water production. has contacted Mixergy for clarification.

According to the manufacturers, the CubeX unit can provide space heating and hot water and is designed for smaller homes and apartments, offering high performance at a reduced footprint.

Heat pump ready

This is the second wave of funding to be granted under the Heat Pump Ready initiative’s efforts to optimize heat pump development – also known as Stream 2. The first wave of funding – £15 million (€17.4 million/$18.7 million) – was awarded to 24 projects in September 2022. Of those, the Highly Flexible Storage Heat Pump from Kensa Heat Pumps is the only one to use a natural refrigerant, with the company saying its outdoor heat pump uses a “natural refrigerant … that requires a high level of venting.”

Another 11 projects have received funding from the initiative to focus on the deployment of high-density heat pump projects.

The Heat Pump Ready initiative is a £60 million (€69.7 million/$79.1 million) aid scheme program funded by the DESNZ as part of its Net Zero Innovation Portfolio and aims to accelerate the adoption of residential heat pumps in the U.K.

Similar efforts have been seen in various regions over recent months. In February, the U.S. Department of Energy announced a second tranche of funding to accelerate the domestic production of residential heat pumps, hot water heaters and related systems and components. The European Commission recently approved a €350 million ($379 million/£301 million) aid scheme for Portugal that will provide funding to companies producing equipment “necessary to foster the transition toward a net-zero economy,” which includes heat pumps and heat pump components.

Boiler Upgrade Scheme

To stimulate the demand side of the U.K. heat pump market, the government is offering grants to consumers in England and Wales to cover part of the cost of replacing fossil fuel-based heating systems with heat pumps.

The Boiler Upgrade Scheme (BUS), which was launched in May 2022 and runs until the end of 2027, provides consumers up to £7,500 (€8,713/$9,378) off the cost and installation of an air- or ground-source heat pump.

In October 2023, the government announced it was increasing the BUS grant amount by 50% – up from £5,000 (€5,809/$6,263) – to support accelerated adoption. It has since seen a significant uptick in the number of grant applications, with more than 2,000 applications submitted per month.

With a charge of roughly 500kg of CO2, the system provides store refrigeration, heating, cooling and sanitary hot water.
Sonia Saini

An integrated CO2 (R744) rack and heat pump system manufactured by Italian OEM Enex Technologies has cut the CO2e emissions of a remodeled Transgourmet Polska hypermarket in Warsaw, Poland, by about 70 metric tons annually compared to the previous system, which used R404A.

Swedish-based Frigo-Consulting and Epta Central North Europe, part of the Epta Group, partnered with Enex on the project.

“This CO2 installation with heat recovery, as well as other store functions, are part of our mission to reduce emissions harmful to the climate and protect valuable resources,” said Bartosz Jankowiak, Technical Department Director at Transgourmet Polska.

According to Enex, the reduction in CO2e emissions mostly comes from the use of CO2 refrigerant, with leaks of synthetic refrigerants accounting for higher equivalent emissions. In addition to moving to a natural refrigerant, the company also acknowledges energy efficiency also plays a role in the reduction.

Besides refrigeration, the integrated system, with a charge of roughly 500kg (1,100lbs) of CO2, provides store heating, cooling and domestic hot water.

“It is sufficient to say that using a natural refrigerant for such a plant size, with a charge of about 500 kg, the ‘content’ in the circuit is reduced by 1,000 equivalent tons of substances producing greenhouse effect,” said Enex.

The system design includes two identical units, with each providing the following capacities:

  • 200kW (56.9TR) of medium-temperature (MT) refrigeration at −3°C (26.6°F) evaporation temperature
  • 32kW (9.1TR) of low-temperature (LT) refrigeration at −28°C (−18.4°F) evaporation temperature
  • 150kW (42.7TR) of air-conditioning at water flow temperatures ranging from 10‒16°C (50‒60.8°F)
  • 360kW (102.4TR) of heating with water flow temperatures up to 42°C (107.6°F)
  • 100kW (28.4TR) of hot water for sanitation purposes at flow temperatures up to 72°C (161.6°F)
Transgourmet Poland Warsaw.
Transgourmet Polska Warsaw. Photo credit: Enex Technologies.

Energy savings

Enex indicates that the installed system reduces overall energy use by roughly 30% compared to the predicted consumption rates. “Combining the ‘warm side’ and the ‘cold side’ of a refrigeration system is attractive because. energy-wise, such systems can be overall very efficient,” the manufacturer said.

The average winter highs in Warsaw are close to 1.7°C (35°F). Enex reports that the CO2 system meets all of the store’s heating needs for climate control and sanitation with no additional energy.

According to the manufacturer, the system’s energy savings compared to standard solutions come from heat recovery and other measures, including:

  • recompression of the flash vapor
  • an innovative air-conditioning system
  • ejectors to recover expansion energy
  • Enex’s patented liquid ejector for overfeeding evaporators
  • modulating 3-way ball valves in front of the heat exchangers

“We are more than satisfied with [the] truly efficient and energy-saving integrated installation, with no oil return problems or anything else,” said Krzysztof Blauciak, Project Manager for Frigo-Consulting in Poland.

“We are more than satisfied with [the] truly efficient and energy-saving integrated installation.”

Krzysztof Blauciak, Project Manager for Frigo-Consulting in Poland

Gaining experience

Since its founding in 2004, Enex has pioneered transcritical CO2 refrigeration, with its founder, Sergio Girotto, installing the first CO2 system in an Italian supermarket in 2001.

Enex noted that the success of the integrated system in the Polish hypermarket flows from the refinement of several similar but smaller installations. The company started developing combined systems for heating and refrigeration in 2018.

As part of its participation in the EU-funded MultiPACK project, Enex found integrating CO2 heat pump systems provides space heating, cooling and domestic hot water for hotels at COP values of up to 6.

Last year, a new luxury Swiss hotel opened with an Enex transcritical CO2 booster system, providing refrigeration for 26 MT rooms, 11 MT cabinets and 5 LT rooms across seven restaurants and bars. Heat recovery from the system provides space heating and hot water for the hotel.

“Our mission is to support the global energy transition through climate-tech solutions while making our customers successful,” said Luis Crespro, President of HVAC and Commercial Refrigeration Business Units at Enex Technologies. “We are committed to continuing our efforts to be pioneers in natural refrigeration technology for HVAC&R.”

Besides CO2 systems, Enex offers ammonia (R717), propane (R290) and water (R718)-based HVAC&R solutions. Last month, the company appointed François Audo, most recently a Vice President and Managing Director at Carrier, as its new CEO.

Update: This article was updated on May 15 with new information from Enex about the synthetic refrigerant used in the Transgourmet Polska hypermarket in Warsaw.

“We are committed to continuing our efforts to be pioneers in natural refrigeration technology for HVAC&R.”

Luis Crespro, President of HVAC and Commercial Refrigeration Business Units at Enex Technologies

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