Food Waste through the Food-Water-Energy Nexus Lenses

Abstract

Food waste is a global issue that causes various but significant global impacts, wasting millions of hectares of arable land, 0.75 to 1.25 trillion of cubic meter of water per year, and about 1.5% of the global energy production. In developed nations, food waste occurs mainly at the retail and consumer stage. By 2050, 80% of the global food consumption will take place within cities. Cities are also a key nexus of energy, water, and food flows. Amsterdam offers an interesting case study as the city does not have any comprehensive strategy to tackle the food waste produced within its boundaries. Yet, the city has shown ambitions in transforming itself into a sustainable metropolis with strong renewable energy and circular strategies. This study uses the Food-Energy-Water (FEW) Nexus approach, particularly suited to understand the interactions and interconnections between Amsterdam’s food flows and the energy and water systems. This study performs a Material Flow Analysis to quantify the different food waste (FW) flows and their origins. It finds that households are the main producers of food waste compared to FW-producing businesses in Amsterdam. Bread, dairy, vegetables, and fruits are the largest avoidable FW, while vegetable peels, fruits peels, coffee grounds, and potatoes peels constitute the bulk of unavoidable food waste. It then quantifies the embedded energy and water present within these food flows. Using the latest developments in the field of bio-based economy regarding food waste valorization, it provides an inventory of the potential technologies available to valorize Amsterdam’s FW. The study then quantifies the energy and water inputs of 12 of these food waste-valorizing technologies. This step confirms the large knowledge gap regarding the water and energy intensities of the latest bio-based technologies. The type and amount of recovered resources through these technologies are also quantified. In addition, this study provides a review of the current social and commercial initiatives based in Amsterdam tackling this issue of food waste. It offers a six-category qualitative framework to assess their food waste rescue potential. Then, a new food waste management and valorization framework is proposed, based on the Value Pyramid model from the bio-based economy, the Food Waste Management Hierarchy framework, and the FEW nexus insights developed in this study. This new framework enables to outline strategies for both Amsterdam’s avoidable and unavoidable food waste flows. It suggests anaerobic digestion, Black Soldier Fly bioconversion, and composting as potential FEW-efficient solutions for Amsterdam’s unavoidable FW. Last, Amsterdam’s FW stakeholders are analyzed through their importance, interests, and potential roles in a future FW scheme. It suggests that the municipality and AEB, Amsterdam’s Waste-to-Energy plant should be at the center of a future FW valorization scheme. Overall, this study combines the FEW nexus perspective and the bio-based economy approach to identify the best options to manage and valorize Amsterdam’s food waste.