How Cold Logistics Keeps Things Cold Without Warming the Planet

A European call for projects bringing together twenty-six partners to invent tomorrow’s cold chain. Developed from 2010 to 2014, the Frisbee research program remains a strong statement of the sector’s environmental commitment today. Ten years later, cold supply chain stakeholders are still pursuing initiatives to make their activities more responsible. This includes the work of the La chaîne Logistique du Froid association—founded in 2016—which seeks to limit warehouse energy consumption and carbon footprints.

“ Cold logistics shares a number of environmental impacts with conventional logistics, explains Vincent Kirklar, Real Estate Director at STEF, the European specialist in temperature-controlled transport and logistics services for food products (273 logistics sites in eight countries). These include the carbon impact of freight transport, warehouse land take and building energy consumption. Cooling nonetheless adds further impacts, such as the energy required for refrigeration—in buildings and vehicles—or the use of refrigerants that make cooling possible .”

Even when considering warehouses alone, the use of refrigerants remains the most debated issue in relation to the cold chain’s environmental impact. Historically, discussions first focused on these fluids’ effects on the ozone layer—a threat now eliminated. Today, it is their consequences for climate change that are causing concern. This is reflected in the European regulation known as “F-Gas II,” which has prohibited the most harmful refrigerants since January 1, 2015. Currently under negotiation at European level, F-Gas III regulation is expected to enter into force in 2024, with broader and faster restrictions.

“ Of course, we will not be able to replace all existing systems using obsolete refrigerants overnight, says Jonathan Leguil, technical expert and innovation manager at Axima Réfrigération France, an Equans Group entity. Nevertheless, we now have a range of technologies that enable us to use so-called natural refrigerants. This family includes products such as ammonia, propane and carbon dioxide, which can be recovered from industrial processes. Their impact is not zero, but it is far lower than that of the refrigerants used in previous decades. ” To support this shift in use, the various refrigerants on the market are now classified according to their GWP (Global Warming Potential, i.e., a gas’s warming potential).

Alongside refrigerant use, energy consumption is the second key environmental issue for cold logistics platforms. In practice, it varies depending on company activities (storage, order picking, freezing), the products handled and the type of warehouse (chilled, frozen, multi-temperature, etc.). Some professionals estimate that 60% to 80% of a warehouse’s electricity consumption is tied to its refrigeration process. The carbon impact of this energy use will differ depending on the building’s electricity source. “ Thanks to newly installed technologies, we can readily reduce refrigeration energy consumption by more than 20% compared with the 2010s, says Jonathan Leguil. Digitalization and the measurement of refrigeration-system energy consumption make it possible to commit to performance within a continuous energy-efficiency approach. ” Using CO2 as a cooling transfer medium in combination with ammonia, or in a transcritical cycle, can reduce peak consumption (by 20% to 30%). Conversely, the development of indirect refrigeration systems using glycol water to limit refrigerant quantities or risks can be counterproductive from an energy standpoint.

Digitalization, measurement systems, anomaly monitoring… Cold logistics applies the same methods that have already enabled thousands of industrial operators and commercial-property managers to reduce their bills, sometimes with spectacular gains. “ Between 2017 and 2021, our group increased its overall temperature-controlled storage capacity by more than 25% while reducing its energy purchasing volumes by 4% ,” Vincent Kirklar notes with satisfaction. To further improve its energy footprint, the STEF Group now aims for 20% to 25% electricity self-consumption (through photovoltaic panels) across all its European sites.

Beyond refrigerants and energy consumption, cold logistics players are also working to design their new platforms more sustainably. Unlike so-called “dry” warehouses, temperature-controlled buildings are often owned by the operators. This gives them greater latitude in deciding which improvement work to undertake, but also makes them directly responsible for the investments. That vigilance begins when selecting a location. Their objectives? Optimize the future freight transport plan, protect surrounding biodiversity and embrace a land-efficiency approach. “ Good design directly contributes to the future site’s performance, Vincent Kirklar explains. At STEF, for example, we try to imagine platforms as close to a cube shape as possible. Likewise, having started more than 40 years ago, we were among the pioneers in building multistory warehouses. These are major choices that both reduce land take and limit energy losses. ”

Still at the design stage, it is important to choose low-carbon, highly energy-efficient materials and equipment (refrigeration systems, piping, cables, etc.) in order to adopt the best available option from the outset. “ We have already made progress in reducing environmental impact by acting on refrigerants and energy consumption, Jonathan Leguil believes. Tomorrow, we will obviously need to consolidate everything that exists today. Our companies will also have to accelerate progress on major issues such as digitalization and artificial intelligence to operate and maintain systems, as well as energy storage and recovery. As always, there will be no miracle solution, but rather a range of tools to combine. ” Many options remain to be explored or expanded. The flexibility provided by cooling management, for example, makes it possible to maximize self-consumption of locally produced renewable energy. Similarly, a warehouse could become a net exporter of waste heat to a third party or a district network, provided a heat pump is added to adjust the temperature level. At STEF, a dedicated entity called Blue EnerFreeze was even created to move quickly on issues such as producing renewable energy for cooling and storing it. Launched in 2018, it already has more than 30 employees in Europe, including energy-performance experts, automation engineers, data scientists and solar or wind energy engineers. The sector’s stakeholders are counting on not losing their nerve.