CO2 Solutions

Up until now, those seeking refrigeration solutions in an industrial setting but with a capacity of under 300kW faced something of a conundrum. The new European F-Gas Regulation is moving end-users away from HFCs which are harmful to the environment. At the same time, the use of industrial ammonia systems is unsuitable in certain applications due to its capital costs and toxicity potential when used in enclosed environments. As a result, customers have been forced into adopting modified commercial, line-assembled CO₂ packs, geared towards non industrial applications or HFCs which are subject to phasedown.

Global legislation is putting pressure on industrial users to reduce their environmental impact and the continued use of HFC systems is consequently becoming both less feasible and more expensive over time; the problem is, for industrial processes under 300KW there is no pre-engineered, industrial CO₂ refrigeration packaged alternative – until now.

Star Refrigeration have designed a range of eco-friendly industrial CO₂ packaged solutions to provide a high performance, resilient and a long term solution for smaller scale industrial applications for temperature controlled storage, food and drink manufacturing, inline freezing and chilling, building services, industrial processes, data centres and leisure and ice applications.

Sustainable and future-proof, with attractive performance and an A1 safety rating, carbon dioxide (CO₂) refrigeration systems offer a number of key benefits.

When used as a natural refrigerant, carbon dioxide has a wealth of benefits. CO₂ has no effect on the Ozone layer, and has a global warming potential (GWP) of one – which is thousands of times lower than synthetic refrigerants.

Star Refrigeration range of CO₂ solutions includes:

  • Envichill: single stage transcritical plant for temperature controlled storage applications suitable for temperatures between 0°C and 8°C
  • Envicold: single stage transcritical plant for temperature controlled storage applications suitable for temperatures between -22°C and 0°C
  • Envifreeze: two stage transcritical plant for food production and temperature controlled storage applications suitable for temperatures between – 40°C and -20°C
  • Envichiller: single stage transcritical plant for chiller applications suitable for a range of chiller temperatures


CO₂ is a naturally occurring substance, found in abundance throughout our environment; it is in the air that we breathe and the beverages that we drink.

Increasingly stringent environmental legislation sees operators of refrigeration systems under increasing pressure to reduce or eliminate their use of traditional, high-GWP refrigerants.

This is highlighted by the revised EU F-Gas Regulation (517/2014), which will see the availability of HFCs reduced by 79% between the years of 2015 and 2030, whilst simultaneously introducing step-wise bans on the installation and servicing of systems using higher-GWP refrigerants.

In addition, the Kigali Amendment to the Montreal Protocol, agreed in 2016, saw 197 countries across the globe commit to cutting the production and consumption of HFCs by more than 80 percent by the year 2047.

The continued use of HFC systems is consequently becoming both less feasible and more expensive over time; as evidenced by the adjacent refrigerant price evolution chart.

As a low-GWP natural refrigerant, CO₂ is unaffected by HFC restrictions; thereby representing a reliable, long term and future-proof solution in which businesses can invest with confidence.

With over 25 years of CO₂ experience, Star Refrigeration has an unrivalled track record of providing CO₂ solutions to a broad range of industry sectors. With in-house design, project management, M&E and aftercare capabilities, Star delivers total CO₂ project solutions for end users.

Envifreeze Envichill Envicold Envichiller

  • Multiple semi-hermetic reciprocating compressors for enhanced resilience
  • Low pressure receiver; delivering enhanced efficiency via semi-flooded evaporator operation
  • Welded steel pack pipe work
  • High quality, industrial grade components throughout
  • Fully automated oil management system
  • Integrated control panel with optimised PLC controls and touch screen interface
  • Dual pressure relief valves
  • Energy meters
  • Designed and manufactured in the UK

Refrigerant type

Envifreeze Envichill Envicold Envichiller

  • Future-proof solution which is not covered by the F-gas Regulation
  • 100% environmentally responsible natural refrigerant
  • A1 refrigerant safety rating; CO2 is non-flammable with low toxicity
  • Eliminates the need for water, effluent and compliance with L8 legislation through use of an air cooled gas cooler
  • Minimal site installation requirements with the skid mounted arrangement
  • Optional weatherproof housing allows the system to be situated internally or externally, maximising flexibility and negating the need for a dedicated plant room
  • Robust industrial design, with over 20 years life expectancy
  • Attractive system energy performance
  • Redundancy via multi compressor design
  • Packaged arrangement for straightforward site installation
  • Designed for ease of maintenance
  • Save energy with the option for heat recovery
CO2 Solutions
Rob Lamb
Group Sales & Marketing Director

Related Case Studies

Bidfood’s CO2 Refrigeration System slashes energy consumption by half when compared to UK’s ‘Best Practice’ Guidelines

Client: Bidfood
Location: Glasgow
Sector: Temperature Controlled Storage & Distribution
Equipment: CO2 Solutions
Service: Installation
Refrigerant: CO2

Star Refrigeration has successfully installed two dual temperature refrigeration systems in a newly built temperature controlled storage distribution centre for Bidfood in Glasgow. The systems provide cooling to a new freezer, chill store and marshalling area and have been in full operation since November, 2022.

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Client: BrewDog
Location: Motherwell
Sector: Brewing and Distilling
Equipment: Bespoke General
Service: Installation
Refrigerant: CO2

Star Refrigeration installs future-proof CO2 refrigeration solution for first fully-refrigerated beer warehouse in Europe.

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ASDA CO2 Cascade Plant

Client: ASDA
Location: Lutterworth, Leics
Sector: Temperature Controlled Storage & Distribution
Equipment: Bespoke General
Service: Refrigeration Retrofit & Heating
Refrigerant: R22 to Ammonia & CO2

ASDA gets a more naturally cool Star treatment.

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