Today’s food system is built upon refrigeration. Temperature control is a feature of almost every stage in the supply chain. Cooling has become a necessity for sustaining current food supply chains and global food expectations.
Refrigeration dependency is the result of a number of social, economic and technological developments. For example, due to increased household incomes, people started having more money to spend but less time to shop for food, which pushed the development of supermarkets and house refrigeration. Also, people’s food preferences changed, with a higher demand for processed and frozen meals, and also for foods not locally produced, such as foreign fruit and vegetables that travel long distances.
As a consequence, effective longer-term safe food storage along the supply chain has become vital for maintaining current food systems. The relationships between refrigeration, packaging, food transport, food product innovations and various socio-economic developments have helped create cultural norms and practices that are highly energy-dependent.
The energy use for space cooling in residential and commercial buildings worldwide has more than tripled between 1990 and 2016. According to FAO, the food sector accounts for around 30% of the world’s total energy consumption and around 22% of total GHG emissions. Just refrigerated storage can account for up to 10% of the total carbon footprint for some products when taking into account electricity inputs, the manufacturing of cooling equipment, and GHG emissions from lost refrigerants.
According to OECD/IEA recent report, “there are big differences between countries and regions in the level of energy use for space cooling, mainly due to the underlying need for cooling and the level and pace of economic development”. This is reflected in the per-capita levels of energy consumption, which varies from as little as 70 kilowatt hours (kWh) in India to 1880 kWh in the United States. Africa has some of the hottest locations on the planet, but cooling ownership is still typically below 5%, with a consumption of electricity for cooling amounted to a mere 35 kWh per person on average in 2016.
Avoiding refrigeration dependence is difficult when economic development brings higher demand for food safety, freshness, and quality, and when some economies depend on exporting food to more industrialized countries. The big concern is how sustainable will this demand for cooling and refrigeration be?
Considering world’s limited reserves of fossil fuels, with volatile and rising prices, possess concerns on how this will impact on the future food supply chains and the urgent need to rethink the role of energy when considering options for improving food systems. Energy consumption is particularly important as commodity prices, including food, tend to be linked to global energy prices. As world energy prices fluctuate and show upward trends, so do food prices, which in turn lead to a sharp increase in food insecurity.
The reality is that food production cannot be decoupled from energy consumption, but options towards efficient consumption and energy autonomy exist.
Energy-Efficiency and cold storage
Energy efficient technologies bring a drastic reduction in the amount of energy used, which thus translates into reduced energy bills. Energy efficiency measures often cost money up-front, but in many cases, this capital outlay will be recuperated in the form of reduced energy costs within a short time period.
Through the use of technologies that consume less energy would create a food sector that is less dependent on fossil fuels, whose prices fluctuate the most. Considering a typical refrigerated warehouse, energy consumption levels are about 15% of the total electricity consumption is used for running pumps, motors, fans, conveyors and lighting systems, 5% is for sanitation and cleaning, and the remaining 80% is used for cooling, freezing and refrigeration.
Many cost-effective energy savings opportunities exist for refrigeration systems, particularly for large systems such as cold rooms. New energy efficient technologies of cold storage components such as compressors, electronically commutated evaporator-fan motors, thermal-insulated structures, LED lighting and energy management systems, combined with good practices such as regular maintenance and appropriate cold storage management can bring energy savings of more than 60%.
Renewable energy and cold storage
Building and maintaining robust on-farm-to-retail cold chain solutions is required to sustain the growing food demand and reduce postharvest food losses. Thus, apart from the large cold storage chambers for long-term storage, cooling systems are also required for on-farm storage so that the produce gets cooled immediately after harvest.
However, in most tropical rural areas grid power supply is very poor with respect to its quantity and quality. In consequence, rural agrifood systems rely heavily on fossil fuels, such as diesel for running energy generators, and grid-energy expenses can account for more than 30% of total expenses in cold storage.
Renewable energies such as bioenergy, solar, wind, hydro and geothermal can be used in agrifood systems as a substitute for fossil fuels to generate electricity for use on farms and supply chain operations. Solar power is the one of best solutions for operating small cold storage systems in tropical countries, for reasons such as: (i) there are good levels of solar radiation throughout the year; (ii) energy autonomy and independence from unreliable or inexistent grid; (iii) no energy related operating costs; (iv) integration of battery backup for storing solar power generated during the day and supply power during night and cloudy weather; and (v) zero emissions systems.
From a rural development perspective, moving into renewable energy resources allows rural communities to produce and preserve more food, raise incomes and improve livelihoods, by harnessing them to deliver energy services, such as lighting and communication that can improve local education and health services and raise the quality of life for individual families.
Paula Rodriguez - Head of Community & Marketing of InspiraFarms, a GCCA member company that produces energy-efficient refrigerated storage and food processing plants that meet global food certification standards and operate on and off grid.