Cities hold the vast majority of human population. Globally, they are responsible of 70% of the waste production and consume around 80% of the food produced.

COVID-19 pandemic has shown the low resilience of cities in terms of food production resulting in fearful population for possible food scarcity. This project wants to enhance cities resilience, sustainability and health through nearness agriculture and recycling/reduction of waste.

This project will focus into different areas. There will be a study to analyse consumption patrons, food waste and material waste dynamics change due to single use materials (derived from pandemics recommendations) on Barcelona metropolitan neighbourhoods. It will also quantify the social acceptance for rooftop agriculture and waste management on-site. Emission factors will be obtained from experimental installations in the university and schools. With those studies we expect to achieve a compendium of new circularity strategies focused on nearness agriculture.

The coronavirus pandemic that began in 2020 has shown us that cities were not prepared for this type of catastrophe. Cities concentrate services, jobs, foster social interactions, and so on. In contrast, they also generate 70% of the world’s waste, and consume 80% of the food produced globally. Due to these facts, the lack of resilience of the cities has been noted, expressed through the fear of possible shortcomings in the distribution of food during confinement. This project aims to transform cities into resilient, sustainable and healthier spaces for the current and future pandemics, through local agriculture and recycling / waste reduction.

The general objective is to propose a framework for the self-sufficiency of resources, the reduction of waste and the improvement of sustainability and circularity within schools, buildings and towns with a pilot and municipal analysis, which help the adaptation of cities to unusual situations such as a pandemic.

Goals

We plan to:

• Study the metabolism of waste, as the situation experienced during the state of alarm has had a clear impact on the consumption habits of families
• Promote domestic and community composting in buildings and schools.
• Promote local agriculture, especially through indoor production.
• Analyze environmentally the different processes associated with the three previous approaches by characterizing the emission factors of certain compounds (N2O, Volatile Organic Compounds and Methane) and analyzing the life cycle of products.
• Scale recycling systems and indoor crops in the town. A case study will be carried out focusing on three neighborhoods of Cerdanyola del Vallès in the metropolitan area of Barcelona to know and analyze consumption patterns and food waste, as well as changes in waste generation due to the increase in use of single-use containers due to the recommended hygienic measures for the prevention of COVID-19 infections.

P1. Environmental analysis.

Subtask P1.1 Circularity of nutrients through the recycling of organic waste.

Domestic composting of organic waste generated in roof crops is proposed as a system for recovering and recirculating organic matter and nutrients (nitrogen and phosphorus). Pilots will be set up at the UAB facilities and schools, where the use of different equipment configurations will be evaluated with the aim of optimizing the process in the following aspects: optimizing initial mixing for the nutrient conservation, and optimize process time in order to maximize nutrient production while ensuring the stability of the final compound. This task will also take into account some aspects related to the design of composters considering functional aspects, especially related to the control of the process and possible emissions, and aesthetics in order to improve their integration into buildings. On the other hand, the domestic and community composting of the organic fraction generated in homes will be evaluated and its integration in the roofs of buildings and schools will be studied.

R.P.1. At the end of these pilots there will be a guide on how to set up and operate composting and plant production systems in buildings and schools to optimize resources.

Subtask P1.2 Life cycle analysis of materials and processes used on a pilot scale.

The impacts generated by waste and the implementation of the AEAR nexus on pilots in schools and building roofs will be analyzed: environmental impacts associated with new waste fractions (masks, for example) on pilots and their implementation new systems of agriculture and production of local resources and in a sustainable way, also includes new materials and adaptive construction solutions, from a life cycle perspective, from the extraction of materials to their end of life. The implementation of composting systems, orchards in schools, roof crops, solar panels, rainwater collection, separation with partitions or others associated with waste generate impacts that must be analyzed in advance. The ISO 14040-44 standardized LCA methodology will be used. A complete inventory will be made of each type of system, crop systems, energy production, rainwater harvesting and waste management and then calculating its environmental impact. The impact of the production of these systems will be calculated and compared for future scenarios in towns. To carry out this task, the pilots of agricultural production will be set up in the experimental facilities of the UAB. During the 18 months of the project different plant species (lettuce, tomato, green bean (Phaseolus vulgaris), basil, lettuce, among others) will be the subject of research. The cultivation system will be hydroponic in perlite and compost substrate, and in some cases also the use of LED light.

R.P.1.2 At the end of this task, the LCA of the fractions of waste generated due to the pandemic and the composting and local agricultural production systems studied will be taken into account.

P2. Analysis of VOC and other greenhouse gas emissions.

Assignment 2. Determination of emissions of volatile organic compounds, methane and N2O. Gas chromatography will determine the emissions of VOCs (considering speciation in VOC families) and N2O, both from indoor crops and from the composting process, including in this case methane, and during the application of compost in the soil / substrate of cropping systems. In this way, the potential emissions of these compounds will be quantified given their impact on the environment, and guidelines will be given for their minimization if necessary. In the case of crops, we will work mainly with basil and green beans, and a tomato campaign. In the same way, the application of the compost will be carried out in such a way as to minimize these emissions. Fertilization will differ depending on the N fertilizer used being the control in the form of NO3- and alternative fertilizers will be used such as struvite from wastewater treated in urban water treatment plants and the atmospheric N2-fixing bacterium Rhizobium.

R.P.2.1 At the end of this task, the emission factors of VOC, methane and N2O will be taken for the domestic and community composting process, and for the local production of green beans, and basil as model species, and approximate values for the tomato.

M1. Consumption patterns and food waste.

Subtask M1.1 Analyze the consumption patterns of the residents in the case study.

The impact of the pandemic (both during and after confinement) on the selective generation and separation of waste will be assessed, with special emphasis on the organic fraction. From the different fractions, we want to identify trends in the generation, especially in disposable packaging and its type (whether they are biodegradable or compostable or is waste material). As well as the quantification and destination of new waste generated by the health crisis (masks, gloves, construction materials, plastic frame, etc …). Similarly, basic resource consumption patterns have changed during the pandemic, as families telework and spend more time at home. The patterns of consumption of food, energy and water will also be analyzed to know the plausible demand of each flow at municipal and neighborhood level, on the one hand to identify the patterns of consumption in each area and on the other hand, to then identify the urban metabolism of the town and changes in the current pandemic and prepandemic. Data from distribution companies will be used and a neighborhood-wide survey will be designed to focus on food consumption and waste generation patterns. This last point will take into account factors such as the change in the frequency of purchases, and in the number of meals at home, the type of consumption (fresh, pre-cooked, prepared, or canned) and potential for organic waste generation and of food waste in pandemic households.

R.M.1.1 At the end of this task there will be a complete identification at municipal and neighborhood level of consumption patterns and waste generation.

Subtask M1.2 Urban metabolism of the case study and food waste.

With the data extracted from subtask M1.2 and a multivariable analysis such as the Multi-scale Integrated Analysis of Societal and Ecosystem Metabolism methodology will be applied to establish a link, in quantitative terms, between the socioeconomic processes described at local level (town and neighborhoods), analyzing the viability (internal constraints) and viability (external constraints) of food, energy, and water metabolic patterns. This methodology offers a series of extensive and intensive indicators to identify the type of metabolism of the town and neighborhoods, identifying the “hotspots” where to act. This methodology has been applied in the town of Badia del Vallès. The affordability of food at the neighborhood level will also be calculated by estimating the cost of an optimized diet (minimum cost reaching the micro and macronutrients suggested by the World Food Program and FAO) and a diet taking into account the eating habits of the person. The cost of the diet will be done using the Cost of Diet, developed by Save the Children, which combines economic and nutritional data. In addition, for vegetables, the cost of the diets themselves will be estimated using the prices of organic products, estimating the differences in environmental and economic impact. Based on consumption data, the amount of food waste generated in a year at the neighborhood level will be estimated, broken down into avoidable, possibly avoidable, and unavoidable. And it will be compared to the one generated annually to strengthen the estimate. The categories of food waste will be investigated through the survey and focus groups to measure differences between different consumption and buying habits.

R.M.1.2 At the end of this task will have characterized the metabolism at the municipal and neighborhood level and food waste in the same areas.

M2. Social acceptance of the implementation of the AEAR nexus on the roofs of buildings and sustainability analysis of viable scenarios for the case study.

Subtask M2.1 Social acceptance of the use of roofs.

A survey will be conducted to measure social acceptance of deck use. This task includes the design of a survey on concerns, perceptions, benefits, barriers to the use of roofs to implement different systems, such as greenhouses, outdoor agriculture, photovoltaic panels, solar thermal panels and ‘rainwater on a municipal scale. It will ask about the concerns in the supply of energy, food and water in the near future and related to the current moment of pandemic. They will also be asked if they would put some systems on the covers and comprehensive questions about each system. These questions will include: a) possible implementation locations; b) acceptance to use the covers. The reasons for not using the covers. Analyzing the possible opposition to the use of decks, reaction “Not in my backyard” (NIMBY); c) preferences of the different systems. Comparing and contrasting the different possibilities such as urban agriculture (outdoor cultivation and greenhouse), solar panels (photovoltaic and solar thermal) and rainwater harvesting; d) barriers in the implementation of the different systems; f) benefits of this strategy.

R.M.2.1 At the end of this task, the social acceptance of the uses of the roofs to implement different systems will be characterized. Specifically, the social viability of this new urban strategy of municipal self-sufficiency in the current pandemic situation.

Subtask M2.2 Sustainability analysis of viable scenarios.

A first participatory process will be proposed in the neighborhoods studied, using the World Cafè methodology. The first workshop with residents, at the beginning of the project, will be to design future scenarios and select relevant indicators. A sustainability analysis will be used to analyze the proposed scenarios, with environmental, social and economic indicators. These indicators will emerge from the previous subtasks, as well as from the first participatory process carried out. Finally, there will be a second workshop to choose the scenarios preferred by residents for the town and the different neighborhoods studied. Achieving the different results and combining them with the acceptance and needs of residents, we can propose a more precise and appropriate scenario or scenarios for the implementation of urban agriculture (outdoor agriculture and greenhouse), energy use and catchment of rainwater on the roofs of this town.

R.M.2.2 At the end of this task there will be a sustainability analysis of the different scenarios for the town and the neighborhoods and the preference of the residents to use their roofs.

C0. Coordination.

Project coordination.