Estimating the magnitude of food waste generated in South Africa.

Throughout the developed world, food is treated as a disposable commodity. Between a third and half of all food produced for human consumption globally is estimated to be wasted. However, attempts to quantify the actual magnitude of food wasted globally are constrained by limited data, particularly from developing countries. This article attempts to quantify total food waste generation (including both pre-consumer food losses, as well as post-consumer food waste) in South Africa. The estimates are based on available food supply data for South Africa and on estimates of average food waste generation at each step of the food supply chain for sub-Saharan Africa. The preliminary estimate of the magnitude of food waste generation in South Africa is in the order of 9.04 million tonnes per annum. On a per capita basis, overall food waste in South Africa in 2007 is estimated at 177 kg/capita/annum and consumption waste at 7 kg/capita/annum. However, these preliminary figures should be used with caution and are subject to verification through ongoing research.

Costs of food waste in South Africa: Incorporating inedible food waste.

The economic, social and environmental costs of food waste are being increasingly recognised. Food waste consists of both edible and inedible components. Whilst wastage of edible food is problematic for obvious reasons, there are also costs associated with the disposal of the inedible fraction to landfill. This is the third in a series of papers examining the costs of food waste throughout the value chain in South Africa. The previous papers focused on the edible portion of food waste. In this paper, costs associated with inedible food waste in South Africa are estimated, in terms of the value foregone by not recovering this waste for use in downstream applications, such as energy generation or composting; as well as costs associated with disposal to landfill. Opportunity costs are estimated at R6.4 (US$0.64) billion per annum, or R2668 (US$266) per tonne. Adding this to the previous estimate for edible food waste of R61.5 billion per annum (in 2012 prices; equivalent to R65 billion in 2013 prices) results in a total opportunity cost of food waste in South Africa (in terms of loss of a potentially valuable food source or resource) of R71.4 (US$7.14) billion per annum, or R5667 (US$567) per tonne. Thereafter, estimates of the costs associated with disposal of this food waste to landfill, including both financial costs and externalities (social and environmental costs), are taken into account. These costs amount to R255 (US$25) per tonne, giving rise to a total cost of food waste in South Africa of R75 billion (US$7.5 billion) per annum, or R5922 (US$592) per tonne. This is equivalent to 2.2% of South Africa's 2013 GDP.

Costs of food waste along the value chain: evidence from South Africa.

In a previous paper (Nahman et al., 2012), the authors estimated the costs of household food waste in South Africa, based on the market value of the wasted food (edible portion only), as well as the costs of disposal to landfill. In this paper, we extend the analysis by assessing the costs of edible food waste throughout the entire food value chain, from agricultural production through to consumption at the household level. First, food waste at each stage of the value chain was quantified in physical units (tonnes) for various food commodity groups. Then, weighted average representative prices (per tonne) were estimated for each commodity group at each stage of the value chain. Finally, prices were multiplied by quantities, and the resulting values were aggregated across the value chain for all commodity groups. In this way, the total cost of food waste across the food value chain in South Africa was estimated at R61.5 billion per annum (approximately US$7.7 billion); equivalent to 2.1% of South Africa's annual gross domestic product. The bulk of this cost arises from the processing and distribution stages of the fruit and vegetable value chain, as well as the agricultural production and distribution stages of the meat value chain. These results therefore provide an indication of where interventions aimed at reducing food waste should be targeted.

The costs of household food waste in South Africa.

Food waste is problematic for a number of reasons, including the loss of a potentially valuable food source or resource for use in other processes (e.g. energy generation or composting), wasted resources and emissions in the food supply chain, and problems associated with the disposal of organic waste to landfill. This paper quantifies the household food waste stream in South Africa, in order to draw attention to the magnitude of the problem. In addition, it estimates the economic (monetary) value of the wasted food, as well as the costs associated with disposing putrescible food waste to landfill, in order to highlight the associated costs to society. Costs associated with the loss of a potentially valuable food source are valued using a weighted average market price of the wasted food. Costs associated with the disposal of food waste to landfill are quantified based on estimates of the financial and external costs associated with landfilling. For household food waste alone, the costs to society associated with these two food-waste related problems are estimated at approximately R21.7 billion (approximately US$2.7 billion) per annum, or 0.82% of South Africa's annual GDP. These costs are therefore significant, particularly considering that household food waste accounts for less than 4% of total food losses across the food supply chain.

Pricing landfill externalities: emissions and disamenity costs in Cape Town, South Africa.

The external (environmental and social) costs of landfilling (e.g. emissions to air, soil and water; and 'disamenities' such as odours and pests) are difficult to quantify in monetary terms, and are therefore not generally reflected in waste disposal charges or taken into account in decision making regarding waste management options. This results in a bias against alternatives such as recycling, which may be more expensive than landfilling from a purely financial perspective, but preferable from an environmental and social perspective. There is therefore a need to quantify external costs in monetary terms, so that different disposal options can be compared on the basis of their overall costs to society (financial plus external costs). This study attempts to estimate the external costs of landfilling in the City of Cape Town for different scenarios, using the benefits transfer method (for emissions) and the hedonic pricing method (for disamenities). Both methods (in particular the process of transferring and adjusting estimates from one study site to another) are described in detail, allowing the procedures to be replicated elsewhere. The results show that external costs are currently R111 (in South African Rands, or approximately US$16) per tonne of waste, although these could decline under a scenario in which energy is recovered, or in which the existing urban landfills are replaced with a new regional landfill.