The project involves replacing an existing conventional, centralised, or direct expansion installation with a refrigeration system using CO2 as a fluid which is transferred in a transcritical or subcritical cycle (cascade or refrigerant) to the units diffusing the cold (refrigerated units, cold room evaporators, etc.) for a positive or negative application, or both.<\/p>\n\n\n\n
This system applies to existing commercial buildings, particularly food distribution premises. This includes spaces intended for the display or self-service of fresh products for the public, such as hypermarkets, supermarkets, and small food stores. Drive-through facilities and click and collect points allowing the public to pick up their purchases without actually entering the store (the \u201cdrive-through\u201d concept) as well as refrigerated warehouses.<\/p>\n\n\n\n
Setting up this new technology will allow the company to save electricity, while reducing its carbon footprint. However, implementing this measure can be complex and requires the temporary shutdown of production during the technical installation stage.<\/p>\n\n\n\n\n\n\n\n
This technology will replace positive or negative refrigeration facilities using R404A as a refrigerant. These refrigeration installations are centralised or decentralised (direct expansion) and often, the positive and negative refrigeration circuits are separate. It is important to know that R404A is a widely used refrigerant that will no longer be available on the market from 2030.<\/p>\n\n\n\n
In a subcritical CO2<\/sub> refrigerant plant, the condensation process takes place in a two-phase refrigerant, the vapours of which are recondensed by a primary \u2018synthesis\u2019 fluid or ammonia, to produce refrigeration at a positive temperature.<\/p>\n\n\n\n In a subcritical CO2<\/sub> cascade system, condensation takes place in cascade on a production unit using a primary \u201csynthesis\u201d fluid or ammonia for negative temperature refrigeration. In a transcritical CO2<\/sub> system (booster), condensation takes place in direct expansion using CO2<\/sub> as refrigerant in a transcritical cycle. In this latter configuration, the plant performance can be optimised by installing parallel compression and ejectors <\/p>\n\n\n\n The use of subcritical or transcritical CO2<\/sub> offers several advantages.<\/p>\n\n\n\n First, the refrigeration cycle is optimised compared to a standard system, which limits the space requirement. This system also offers the possibility of recovering a significant quantity of heat during desuperheating. In addition, the use of a weak fluid contributes positively to lessening global warming. <\/p>\n\n\n\n Estimated annual electrical savings can reach up to 20% with CO2<\/sub> booster technology and up to 36% using CO2<\/sub> booster technology combined with parallel compression and ejectors.<\/p>\n\n\n\n Source: ADEME. (January 2020). Refrigeration plant using subcritical or transcritical CO2<\/a>. File BAT-EQ-117. Association Technique \u00c9nergie Environnement (ATEE). <\/p>\n\n\n\n Please note: any application for government or non-government subsidies must comply with the \u201cincentive effect\u201d, subject to compliance with the subsidy conditions.<\/strong> SME Packages – Sustainability<\/strong><\/a><\/p>\n\n\n\n Aid for environmental protection<\/strong><\/a><\/p>\n\n\n\n The law of 8 December 2025 on the renewal of the aid scheme for environmental and climate protection provides for the granting of investment aid to SMEs and large companies established in Luxembourg, with a business licence, and carrying out projects that contribute to environmental or climate protection. The following maximum rates apply:<\/p>\n\n\n\n<\/span>Energy and environmental impact<\/h3>\n\n\n\n
<\/span>State subsidy application<\/h3>\n\n\n\n
State subsidies<\/h4>\n\n\n\n
To ensure that the \u2018incentive effect\u2019 is respected, no binding commitment (signing a quotation; paying an advance) may be made BEFORE submitting the application file or receiving the agreement in principle from the State or the electricity and natural gas supplier following an application for subsidies.<\/p>\n\n\n\n\n
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This aid supports investments aimed at improving energy efficiency outside buildings. It is intended for initiatives that either reduce energy consumption by at least 20% or achieve energy savings of at least 250 MWh per year.<\/p>\n\n\n\n