Bio-waste prevention

Waste prevention is at the top of the waste hierarchy, and as such should always be the most preferred option. As opposed to other options, waste prevention does not tackle waste directly, but rather aims to prevent its generation by looking at earlier stages of products' life cycles, including primary production, processing, and distribution. Often overlooked, waste prevention is nevertheless crucial for the transition to a circular economy, and requires thinking beyond waste, reinventing the way we extract raw materials, the way we produce and the way we consume.

The nature of organic matter and biological cycles means that preventing bio-waste is different than preventing waste in other material streams, and especially that options such as re-use, repair or refurbish are simply not possible here. With 59 million tonnes produced across the EU in 2020 only, tackling food waste is the most pressing issue, as it accounts for about 16% of the total GHG emissions from the EU food system. Aside from climate change, conventional agricultural practices in Europe are also responsible for substantial biodiversity loss, chemical pollution, nutrient flows alteration and water scarcity. Tackling food waste would therefore mechanically reduce the impacts of food that ends up being lost or wasted. This is the reason why food waste prevention has become a strategic priority for the European Commission, and member states are invited to set targets, monitor, and reduce food waste.

This section includes four different instruments, all developed by Porto: the food demand management model, the circularity decision-making support tool, the circular procurement guidelines, and the sustainable green space certification system. These instruments cover two main categories of bio-waste: food waste and green spaces waste. For food waste specifically, this will allow local authorities to prevent waste generated in the HORECA sector (including social institutions) as well as from catering activities.

CityLoops demonstration experiences

Bio-waste circularity in the bio-waste and social economy sector

Porto implemented Bio-waste circularity models in hotels and resutaurants to improve their circularity. One example is the Grande Hotel de Porto, which applied the circularity decision making support tool to identify which good practices already exist, and what actions can be taken to improve the circular performance of the hotel. This resulted in in-house vegetables production on the rooftop, food waste reduction through the Dose Certa project, and urban waste separate collection.
More information about this demonstration action can be found in Porto's Bio-waste demonstration report.

Reducing food waste via food donation network

Porto established a partnership with Zero Waste Portugal to expand its food donation network to support citizens with low income and social needs. Within the network, municipal services related to social and school canteens, as well as restaurants, hotels and companies in the wholesale and retail sector work together with social organisations to redistribute quality food to citizens in poor living conditions. Zero Waste Portugal was established in response to the economic and social crisis, when enormous amounts of meals and end-of-life food went to mixed waste containers, animal feed or compost
More information about this demonstration action can be found in Porto's Bio-waste demonstration report.

Lessons learnt

Local authorities can prevent food waste from school meals and catering through capacity building or public procurement.
Effective planning and inventory management practices should be promoted, involving demand forecasts, optimising ordering and stocking practices and implementing just-in-time inventory systems.
Food waste can also be prevented by promoting more sustainable diets and seasonal and local products.
Local authorities should raise awareness among citizens about food waste and provide practical tips on food storage, portion planning and utilising leftovers.
In Seville, Lipasam worked with school children to teach them how to to learn how to minimise waste when cooking. It is an example of how local authorities can play a role in promoting and enabling sustainable food production.
Reducing supply chains can also reduce food loss. This means reducing the distance and number of intermediaries involved in the process of getting food from the producer to the consumer. It involves minimising the transportation and handling of food by bringing it closer to its point of consumption.
Porto's food management model can be transposed to any context. However, for it to be used, it is necessary to gather and structure the historical information that is put into the model. The developed model is data-driven, and consequently it implies first the definition of the explanatory variables of demand, as well as their collection. Once this collection and corresponding data structuring and pre-processing completed, the tool can be used.
Most entities (i.e. restaurants) lack the data needed to implement the food management model, or they have different data (financial records) that cannot be used (low quality data). This is a barrier, but is also a great opportunity for these entities to improve their food acquisition, since they will be able to forecast their needs based on historical records, hence reducing the bio-waste produced.
When using the procurement guidelines, it is very important: to ensure the commitment of the board and the political alignment and support. Furthermore, purchase departments need to gather experts and tackle resistance to change and innovation. Finally, training courses need to be developed for different audience (e.g purchasing departments need to be trained differently than suppliers.
It is crucial to involve all the main stakeholders in the process of developing a green spaces certification system. By doing so, there is a higher chance of achieving greater success with the certification system implementation.
The green space certification system was developed to be applied to diverse green spaces with different dimensions and may respect its specific characteristic (historical, urban, peri-urban, high, or low use intensity).
The Green Spaces certification system needs to remain open to receive improvements from the first pilots. Therefore, it is essential to consider the tool’s adaptability to specific spaces. For example, criteria such as water use may be irrelevant in a dry garden or require customisation.

CityLoops instruments

Food demand management model

The food demand management model aims to prevent food waste in the social and tourism sectors by forecasting food demand based on historical data. In the City of Porto, the social economy and the tourism sectors are major producers of food waste that could be avoided. To provide them with better tools to reduce food waste, this model has been developed to predict food waste in these two sectors. The food demand management model is a mathematical model for predicting food waste flows in the social and tourism sectors. Using machine learning algorithms, the tool was fed with historical data from partners from previous projects that have the historical records needed for the algorithm. The model is intended to be used to form the basis of a dashboard for the daily management of food demand and supply fluctuations in restaurants and/or canteens, whether they are part of hotels, social institutions, or independent entities. This will also allow purchase procedures to be adjusted to the needs of the market based on the forecast provided by the tool.
The tool can be downloaded here.

Circularity decision making support tool

The circularity decision making support tool is designed to assist social institutions, hotels, restaurants, citizens, and tourists in assessing the circularity impacts of their catering decisions. It relies on a multicriteria analysis method which encompasses environmental, technical, and economic criteria. It shows users their level of circularity and guides them towards the most circular choice of what to do in the several steps where organic matter is used, bought, eaten, or discarded, following the Lansink Ladder. Users can insert measures framed in 5 distinct stages in the management of organic flows in their business model: product acquisition, storage, cooking, customer contact and surpluses elimination. The tool can be downloaded here.

Circular Procurement Guidelines for the Social Economy and Tourism Sector

The set of guidelines focuses on canteen and catering services by social institutions and the tourism sector on one side, and the maintenance of urban green spaces by the municipality, on the other. The Porto Circular Procurement Guidelines are based on an integrated vision for circular economy for school meals & catering services and green spaces maintenance. At a more practical level, the guidelines help in finding the relevant actors to achieve the objectives set with the procurement action, identifying possible gaps and consequently the need for new products and services. At the micro level, the tool includes information on how to define and develop criteria along the stages of the procurement procedure, including a comprehensive set of example criteria to implement circular procurement in these sectors (criteria available in the tool). These procurement guidelines, specific for bio-waste flow (food services and green spaces) were developed, and are now available, to be also used by other cities. They can do so by applying the presented sets of example criteria that promote circularity in the food and public space maintenance sectors. The guidelines can be downloaded here.

Green space certification system

The purpose of the Green Space Certification System is to stress the importance of sustainable green space management, through the adoption of good practices for the promotion of biodiversity, the maximisation of benefits provided by the ecosystems and the recognition of spaces where these topics are already being addressed, so that citizens can appreciate and benefit from more natural spaces in urban areas. Active communication and information among citizens/users to promote their engagement is paramount to the success of this conversion process. The certification methodolgy can be downloaded here.

Bio-waste prevention

CityLoops demonstration experiences

Lessons learnt

CityLoops instruments

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