Keeping food cold as it moves through the supply chain is crucial to fighting food insecurity, preventing food waste, and supporting agricultural livelihoods and economies throughout the developing world.
But each step and technology of the cold chain — refrigerators, industrial chillers, and transportation — has significant potential impacts on climate change, from massive energy demands to powerful fluorinated greenhouse gas emissions.
Together, these impacts make global food system refrigeration responsible for up to 5% of global energy needs and 2.5% of total greenhouse gas emissions.
Rising global temperatures and emerging economies will continue to drive demand for massive new cold chain infrastructures.
Can we avoid a runaway cycle of cooling technologies contributing to the very causes of global warming?
Necessary Technologies With Significant Climate Impacts
Cold chains are critical components of local, national, and global food systems, but they can have significant climate impacts.
More than 1.6 billion tons of food are wasted annually throughout the global food system. That’s 13% of the world’s total food production — enough to feed 950 million people — that is either lost in the food supply chain or wasted by end-consumers. This food loss and waste represents significant embodied carbon emissions — from upstream land and energy inputs to transportation and methane emissions in landfills — that total nearly 4.4 gigatons of carbon dioxide equivalent emissions each year.
Cold chain technologies can reduce food losses within the supply chain and mitigate this wasteful emissions footprint. Approximately 144 million tons of food loss could be reduced in developing countries alone with proper cold storage.
But these technologies come with clear emissions trade-offs. Almost every step of the cold chain — from post-harvest forced-air chillers, refrigerated trucks and shipping containers, to industrial cold storage — requires massive amounts of energy to keep foods from spoiling. And when these energy demands are met with fossil-fuel power, the emissions footprint of cold chains quickly adds up. In 2018, refrigeration accounted for nearly 5% of global energy needs, making these technologies alone responsible for 2.5% of total emissions that year.
Cooling technologies also leak powerful greenhouse gases directly into the atmosphere. Fluorinated gases (F-gases) are used as refrigerants in cold chain technologies and have an enormous potential to contribute to global warming; in some cases, they are 25,000 times as powerful as carbon dioxide at atmospheric warming. According to data released by the Food and Agriculture Organization of the United Nations (FAO), global food-related F-gas emissions increased, on average, by 13% from 2000 to 2007, and have remained stubbornly high since then.
Taken together, these energy demands and F-gas emissions make global food cold chains responsible for up to 3.5% of the world’s carbon footprint.
Climate change will continue to fuel demand for more refrigeration and global cold chain development, especially in developing countries.
The twin pressures of global economic and demographic growth will require food systems to meet ever-higher demand — as much as 70% more production of plant and animal products by 2050. And as global temperatures continue to rise (1.02 °C and counting), there will be even greater demand for cooling technologies. According to the International Energy Agency, as many as 14 billion cooling appliances, including non-food related technologies, will be needed by 2050.
Cold chains are expanding rapidly within developing countries and emerging economies, with China’s cold chain market expected to nearly double by 2026. According to FAO data, developing countries are currently responsible for only 6% of global F-gas emissions from food systems, though this share is likely to only grow. These same countries are poised to benefit most from the advantages of expanded cold chains, including bolstered food security, improved livelihoods for farmers, and adaptation to increased heatwaves and extreme weather events caused by climate change.
Proposed Solutions
Climate-sensitive technologies and policies need to close this runaway feedback loop and maximize the benefits of expanding cold chains.
Faced with these pressures, how can global cold chains expand without exacerbating a major source of climate change?
National and regional projects, like the Africa Centre of Excellence for Sustainable Cooling and Cold-Chain, are working to build capacity for new cold-chain markets and low-carbon technologies in sub-Saharan Africa through local trainings, research and development investments, and battery-powered food transport projects.
Companies with major public climate commitments are also racing to develop cleaner refrigerated cold chains. One of Walmart’s core pillars to meet its ambitious Project Gigaton targets include transitioning to hydrofluorocarbon (HFC)-free refrigeration with low-global warming potential across its supermarkets and cold chain, and is piloting a new battery-powered refrigerated trailer. Other major players in the private sector — including Dow Chemical, PepsiCo, and Ingersoll Rand — have made public commitments to eliminate refrigerants with high global warming potential and offer HFC-free products, demonstrating the availability of suitable alternatives and potential for further action.
The 2016 Kigali Amendment to the Montreal Protocol aims to reduce global HFC emissions by 80% by 2047, an impressive multilateral response to the threat of runaway HFC emissions. The US Senate just formally ratified the amendment in October, although developing countries are allowed to wait until 2024, or 2028 in some cases, before freezing their national HFC consumption in line with the agreement. Current F-gas emissions data from the global food system do not yet indicate a significant decline, though it is expected that developed countries will soon deliver on their production and consumption commitments.
As with the broader fight against climate change, it will take a wide range of creative policy solutions and commitments to ensure that we address the climate impacts of cold chains at the scale and pace required to avoid the worst impacts of a rapidly warming world.
Connecting Food Systems and Climate Action
Fortunately, there is already meaningful momentum across sectors to help address the challenges of expanding global cold chains.
But it will take even greater collaboration to ensure that these efforts maximize the benefits of expanded food system cold chains: low-carbon solutions to help mitigate food waste and loss, improve food security and farmer livelihoods, and help communities adapt — rather than contribute — to climate change.
With international policymakers finally starting to connect food systems with global climate action, it’s crucial that we expand these efforts to consider the role of global cold chains on national and worldwide carbon footprints.
Climate-sensitive technologies and policies can help decouple cold chains from their worst climate impacts and will be needed to effectively tackle our global food and climate crises.
Benjamin Ritter and Carolyne Barker are graduate students in Columbia University’s School of International and Public Affairs. Kevin Karl is a research associate at Columbia University’s Center for Climate Systems Research where he focuses on the intersection of food systems and climate change as a member of the Food Climate Partnership.
The Food Climate Partnership is a consortium of scientists and policy practitioners from Columbia Climate School’s Center for Climate Systems Research and Center on Global Energy Policy, the Agricultural Model Intercomparison and Improvement Project, and New York University’s School of Environmental Studies.
