The liquids and gases used in refrigeration systems are highly polluting and are gradually being phased out in favour of replacement technologies. One VINCI Energies Building Solutions business unit has designed a solution as unexpected as it is competitive.
As industry body the Association Française du Froid itself admits, refrigeration installations and technologies present in the agrifood industry, retail distribution, warehousing and heavy industry contribute significantly to carbon discharges: 7.8% of greenhouse gas emissions.
HFCs (hydrofluorocarbons) are particularly problematic, since some of them emit greenhouse gases (GHGs) up to 25,000 times more potent than CO2. Under pressure from European legislation, which is aiming to reduce emissions linked to these products by four-fifths by 2030, the sector is committed to gradually phasing out the most harmful refrigeration liquids and gases, including ammonia (NH3). But what are the available replacement technologies and innovations?
“There are not that many alternative solutions that can be deployed quickly. The best compromise we’ve found for decarbonising refrigeration is actually CO2,” says Djamel Aliouane, Business Unit Manager at IDF Thermic Froid (VINCI Energies Building Solutions).
A first in France
In 2023, this business unit specialising in the design, creation and execution of custom refrigeration technologies designed and implemented France’s first-ever CO2-based direct expansion solution, with 1.8 MW of cooling power. This large project involved the refrigeration systems in a huge warehouse built by a company specialising in meal kits as part of its expansion in France. The budget for the cooling installation was €3.5 million, and it was a large-scale challenge: 17,000 m² (a larger surface area than the Stade de France) to be kept at a temperature of +2 °C, and 700 m² to be kept at a temperature of -20 °C, with a ceiling height of 9 m throughout.
“There are not that many alternative solutions that can be deployed quickly.”
Cheaper, faster, less polluting
“We found ourselves facing three constraints,” explains Djamel Aliouane, “in the form of very tight timeframes (nine months), an environment in a commercial area with very limited space and nowhere to create a machine room, and legislation drastically limiting the use of ammonia. We therefore had to start from scratch and propose a radically innovative solution.”
The cooling installations use CO2 sourced mostly from emissions from the beer and ammonia production industries, which would normally be buried or released into the atmosphere.
This technology presents a number of advantages, including reasonable investment requirements and implementation timescales. “The customer gained €200,000 in French Energy Saving Certificates, and we delivered the installations a month ahead of schedule,” says Djamel Aliouane.
The use of CO2 also drastically reduces the company’s greenhouse gas impact and any public health risk in the event of a leak.
As well as decarbonising the installation thanks to the fluids no longer in use, the CO2 technology makes it possible to reach hotter temperatures under high pressure, allowing far greater waste heat recovery than with equivalent technologies. As a result, the installation no longer requires electric de-icing, because the recovered heat is sufficient to completely de-ice its evaporators. For an equivalent surface area, this represents a 35% reduction in the customer’s energy bill.
12/12/2024
