Carbon footprint and life cycle economic costs of pilot Know-as-you-Throw schemes in Italy and Spain.

Considerable resources are spent globally on actions to improve the separate collection of municipal waste aiming to minimise the environmental and economic impacts of municipal waste management. One of such actions are know-as-you-throw (KAYT) schemes, which aim to change the behaviour of waste generators through tailored communication of information. KAYT schemes offer a relatively uncontroversial and simple tool, yet their environmental and economic performance remains unknown due to their limited implementation. To fill this gap, the LIFE-funded REthinkWASTE project applied a novel KAYT scheme in four pilot areas in Italy and Spain. The results of such pilots were evaluated in terms of carbon footprint and life-cycle costs of municipal waste management. The carbon footprint was notably reduced in all pilot areas, ranging from a 46% to 19% reduction, mainly due to notable reductions in unsorted waste (between 10 and 17% reduction) and subsequent lower treatment impacts. Life-cycle costs slightly increased overall, ranging from 4.6% to a -0.4% change. In addition to various sources of uncertainty, self-selection and recency biases are highlighted as major sources for potentially overestimating the benefits of KAYT in the context of large-scale and long-term KAYT implementation. The results however consistently show that the additional carbon footprint from KAYT actions can be offset with less than a 5% reduction in unsorted waste, well below the observed values. The results robustly reveal the potential of KAYT to notably reduce the carbon footprint of waste management systems with limited investment of economic resources.

Management practices for compostable plastic packaging waste: Impacts, challenges and recommendations.

The EU Green Deal aims at solving the challenges related to plastic production, (mis-)use, and pollution. While the bioplastic industry is identified as one of the possible avenues to tackle the problem, bioplastic waste collection and management practices are still far from full-development and harmonisation. To inform policy makers on the best practices and their feasibility, this study quantifies environmental and economic impacts of compostable plastic packaging (CPP) waste management schemes by means of Life Cycle Assessment and Costing. Results show that, with respect to climate change and financial costs, the scheme leading to the highest benefits is collecting CPP with conventional plastic waste followed by mechanical sorting and recycling (saving ca. 306 kg CO2eq. t-1 at a net income of 3.7 EUR t-1). The second best option is collecting CPP with bio-waste followed by biological treatment (saving ca. 69 kg CO2eq. t-1 at a cost of 197 EUR t-1). Collecting CPP with conventional plastics followed by sorting and biological treatment is to be avoided. The trend on the other impact categories generally follows climate change. Ideally, closed loop is therefore preferred, but conditioned by (i) having high share of CPP in municipal waste (else sorting is economically unfeasible), (ii) good citizen's behaviour at source-segregation, and (iii) an established market for secondary material. Currently, overall benefits are limited by the low amounts, suggesting that the management choice could ultimately be based on rather simple technical and economic feasibility criteria while regulatory and management efforts should be focused on other waste streams with greater implications on environment.