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Technical Summary

Reduced Food Waste

Project Drawdown defines reduced food waste as minimizing food loss and wastage from all stages of production, distribution, retail, and consumption. This solution replaces current reported trends in food waste by region.

Estimates suggest that 30–40 percent of all food produced worldwide is wasted across the supply chain (Smith, P. et al., 2014). When food is wasted, all the energy, resources, and money that went into producing, processing, packaging, and transporting it are wasted too. The further down the supply chain the food gets before it is thrown out, the more resources are wasted to get it to that stage. If measures are taken to reduce food waste by improving storage and transport systems, generating public awareness, and changing consumer behavior, this solution could lead to substantial reductions in waste and carbon emissions.

Methodology

To evaluate the impact of reduced food waste, an independent model was created outside Drawdown’s core model framework to project food consumption and waste from 2020 to 2050. This was required due to the complexity of estimating country- and regional-scale food consumption and waste trends based on reported commodity types along the supply chain.

Total Addressable Market

The global market for reduced food waste is defined as the total demand for food, based on estimated kilocalories supplied per year for consumption by the world’s population. The baseline food consumption is projected for all countries up to 2060 in kilocalories per capita per year, using data compiled by the Food and Agriculture Organization (FAO) for the year 2013.[1] Future consumption is forecasted using growth factors from Alexandratos et al. (2012), which reflect projected dietary changes.[2]

Total food loss and wastage is calculated according to regional estimates of waste generated at each supply chain stage[3] (FAO, 2011), applied to aggregated country-level food demand by commodity type. Current adoption[4] of reduced food waste is considered to be 0 percent.

Adoption Scenarios[5]

Impacts of increased adoption of reduced food waste from 2020 to 2050 were generated based on three growth scenarios. These were assessed in comparison with a Reference Scenario, in which the solution’s market share is fixed at the current levels.

Adoption scenarios in this model grow linearly over time starting from the base year of 2014, and are considered complete in 2050. Linear growth trends were chosen because of the lack of country or regional data; additional behavioral research at more granular scales can reveal more representative adoption estimates.

For reduced food waste, three scenarios were developed:

  • Scenario 1: This scenario assumes that a 50 percent reduction in total global food loss and wastage will be achieved by 2050.
  • Scenario 2: In this scenario, a 75 percent reduction in total global food loss and wastage by 2050 is modeled.

Emissions Model

To estimate emissions, commodity-specific carbon dioxide-equivalent per-calorie values were drawn from several sources (see Audsley et al., 2010; Heller and Keoleian, 2014; Hoolohan et al., 2013; Tilman and Clark, 2014; Vieux et al., 2012) to determine minimum, average, and maximum estimated emissions factors per commodity. The emissions factors were multiplied by the baseline annual food demand by country and commodity to get the carbon dioxide-equivalent values for food items over time. Emissions estimates were aggregated by commodity types[5] and regions classified by the FAO (2011), and are aligned with regions used by Project Drawdown.

FAO regional estimates of food loss and wastage by commodity types across the supply chain stages were applied to aggregated emissions values associated with regional food demand. Emissions reductions were calculated based on the incremental adoption of reduced food waste, which was applied across all stages of the supply chain. Resulting emissions reductions were aggregated to represent the total global reduction from avoided agricultural production.

Integration

Project Drawdown calculated the total reduction in food loss and wastage by weight (in million metric tons) by commodity type. It was assumed that reduced loss and wastage can be diverted to feed current and future undernourished populations. Diverted tonnage of food was used as an input in the Project Drawdown Integrated Yield Model, which combines all agricultural production models to determine the required yield to meet the estimated food and bio-based product demand on an annual basis. Results from all demand-side solutions, i.e., reduced food waste and plant-rich diet, determine the need for land conversion to cropland and grassland in order to meet future food demand. Emissions reductions associated with land conversion were applied to both reduced food waste and plant-rich diet according to the proportion of their contribution to diverted food supply.

In addition, the results of reduced food waste were applied to solution models in the Materials Sector that utilize organic municipal solid waste.

Results

Between 2020 and 2050, Scenario 1 projects the reduction of 90.70 gigatons of carbon dioxide-equivalent emissions: 13.57 gigatons due to diverted agricultural production, 76.33 gigatons from avoided land conversion, and 0.80 gigatons from ecosystem protection.

Scenario 2 projects the reduction of 101.71 gigatons of carbon dioxide-equivalent emissions: 25.97 gigatons due to diverted agricultural production, 74.96 gigatons from avoided land conversion, and 0.78 gigatons from sequestration from ecosystem protection.

Discussion

Food loss and waste has many negative economic and environmental impacts. The global economic, environmental, and social cost of food wastage is estimated at US$2.6 trillion, which is nearly equal to the GDP of France (FAO, 2014). Food waste generates unnecessary greenhouse gas emissions and wastes both water and land, negatively impacting natural ecosystems.

Reducing food loss and waste can also help close the over 60 percent gap between food available today and food needed in 2050, thereby working toward eliminating hunger. Although solutions at consumer level are difficult to implement and hard to measure, they must be pursued at regions with high levels of consumer food waste. Food loss and waste measurement tools must be developed to standardize the measurement and reporting. Food waste reduction targets should be set not only at country levels, but also broken down to corporate, supplier, and consumer levels. Incentives for waste reduction should be designed and provided to influence behavior change. Reducing food waste is a big physical problem. But it has widespread benefits for the economy, the environment, society, and human health. 

Note: August 2021 corrections appear in boldface.


[2] The projected dietary changes show significant impacts for countries like India and China, whose populations are expected to demand more carbon-intensive foods over the next 30 years.

[3] Supply chain stages are defined as: agricultural production, postharvest handling and storage, processing, packaging, distribution, and consumption.

[4] Current adoption is defined as the amount of functional demand supplied by the solution in the base year of study. This study uses 2014 as the base year due to the availability of global adoption data for all Project Drawdown solutions evaluated.

[5] Commodity types include: cereals, roots and tubers, oilseeds and pulses, fruits and vegetables, meat, fish and seafood, and milk.