ACR+

Waste carbon impacts

Without much surprise, discrepancies in waste data and carbon factors lead to different carbon footprints. Yet for the three participants, the emissions linked with the extraction of resources and manufacturing of products that then became municipal waste are significantly higher than the emissions linked with products’ end-of-life.

Three additional observations are made:

• Textile, food, and plastic are the most carbon-intensive fractions for all three territories. The same result was found for Cohort 1. Here again, if recycling has a potential to improve the carbon footprint, especially for plastic, prevention represents a much more important potential.
• The efficiency of waste treatment plants and their outputs can greatly impact the potential savings: the energy efficiency of incineration and anaerobic digestion plants, the production of heat, or the production of biofertilizer were found to have a strong impact on saved emissions.
• The composition of the key waste fractions is a relevant information to identify priorities. For instance, the higher presence of protein waste in Navarra’s food waste strongly impacts its carbon footprint and makes it relevant to focus on this specific sub-fraction.

How to reach the -25% target?

Carbon impacts

The carbon impacts of household waste in Ireland in 2019 were approximately 5.3 million tonnes of carbon dioxide equivalent (tCO₂eq.), or 1.0 tCO₂eq./capita. The analysis shows that carbon saved through recycling was higher than carbon impacts of waste disposal (i.e., incineration and landfilling), meaning waste management activities (i.e., collection, treatment, and disposal) in Ireland is carbon negative. Embodied carbon impacts of waste material are deemed to be the highest contributor to the net carbon impacts of waste, which is why waste prevention, in accordance with the waste hierarchy, always offers the greatest carbon savings. Accounting for the full lifecycle impacts, Ireland’s waste carbon intensity is of 3.4 tCO₂eq./tonne of waste.

The top five waste materials by weight in 2019 (paper and cardboard, mixed and undifferentiated - composed mainly of bulky waste, food, plastic, and textile) accounted for 65% of Ireland’s waste, and 86% of its waste carbon impacts. Unlike other ACR+ members where a similar carbon assessment has been carried out, Ireland’s top 5 waste categories from carbon perspectives (textile, plastic, mixed and undifferentiated - composed mainly of bulky waste, food, and paper and carboard) also have the highest tonnages. Yet it is worth mentioning that textile waste accounts for 42% of the total carbon footprint, while only representing 8% of the total weight generated.

This means that Ireland can achieve high carbon savings and increase recycling rates simultaneously by prioritising the most carbon intensive waste materials mentioned above, such as textiles, plastics, food, and bulky waste.

The way forward

Ireland must reduce its waste carbon impacts by approximately 1.3 million tCO₂eq, to a total of 3.9 million tCO₂eq by 2025, in order to achieve the 25% ACR+ target.

Results suggest Ireland can meet the 2025 carbon reduction target by adopting one of the following strategies:

• Reduce the amount of textile waste by 30%, plastic waste by at least 40%, and the other targeted materials (i.e., food, paper and cardboard, metals, and bulky waste) by 20%;
• Reduce the amount of textile waste by 40%, plastic waste by at least 15%, and other targeted waste by 20%; or
• Introduce a waste reduction target of 25% for all materials.
  

It should be noted that these scenarios prioritise waste reduction over improvements in waste disposal and treatment activities. Ireland seems to have a great opportunity to increase recycling rates, in particular for food waste, plastics and textile. Diverting these tonnages for recycling would ultimately lead to additional carbon savings, but ultimately waste prevention measures are the best approach to reduce the whole lifecycle impacts of waste to achieve the 25% reduction target.

To go further, follow-up activities could include detailed investigation on the actual composition of carbon intensive materials and the identification of actions and policies that could contribute to reach the reduction targets.

Carbon impacts

The carbon impacts of household waste in Odense in 2018 were approximately 140,000 tonnes of carbon dioxide equivalent (tCO₂eq.), or 0.7 tCO₂eq./capita.

In 2018, Odense boasted a 50% recycling rate and sent all its residual waste to incineration with high energy recovery rate (11% electricy and 97% heat). This results in a carbon negative recycling and incineration of household waste. However, the impact of production and consumption of the products that became waste is the highest contributor to the net carbon impacts of waste. Therefore, greatest carbon savings could be offered by waste prevention.

Many of the high tonnage materials (like garden waste, construction and demolition waste) in Odense's waste stream have relatively low carbon impacts. It is not the case of textile, which represents the single greatest carbon impact (nearly 30%) despite accounting for only 1% of waste by weight. A specific focus should thus be placed on this waste material for prevention and recycling. After textile, the most carbon intensive materials are plastics - with a significant fraction still incinerated - and food waste, whose selective collection started in 2018.

The way forward

For Odense, a reduction of 25% means to move from an estimated 140,000 tCO2eq to a total of 105,000 tCO2eq, thus reducing the waste carbon impacts by approximately 35,000 tCO2eq.

The analysis led by ACR+ and Zero Waste Scotland identifies two strategies for Odense to meet the 2025 carbon reduction target:

• Reducing by 40% textile and plastic waste and by 20% the other targeted materials (i.e., food, paper and cardboard, mixed metals);
• Introducing a waste reduction target of 28% for all materials.

As a follow-up, work could be carried out to understand the 19% of residual waste currently assigned to household and similar waste. It could also be worth getting a better insight on the textile and food wastes to know the type of materials captured.

Carbon impacts in 2019

The carbon impacts of household waste in Navarra in 2019 were approximately 713,000 tonnes of carbon dioxide equivalent (tCO₂eq.), or 0.4 tCO₂eq./capita.

Waste management activities in Navarra are carbon-negative, meaning that the carbon emissions saved thanks to recovery operations (energy produced from anaerobic digestion of waste, generation of recycled materials) offset the emissions generated by transport and treatment. Yet the impacts linked with the production of the products that became waste are considerably higher. Therefore, waste prevention is the best way to achieve significant carbon savings.

The top five waste materials by weight in 2019 accounted for 74% of Navarra’s waste quantities, but only 40% of its waste carbon impacts. If looking at the waste categories with the greatest carbon impact, textile comes first. Recycling, but more importantly prevention and re-use for this waste stream are thus a priority. The analysis also reveals that significant amount of food, and paper & cardboard wastes - both have high waste tonnages and significant carbon impacts - are disposed in landfills. Prioritising these categories in future policy interventions will not only reduce carbon impacts but also increase recycling rates in Navarra considerably.

Evolution of the carbon impact of municipal waste 2016 - 2020

The improvement brought to municipal waste management in Navarra between 2016 and 2020 entailed quite significant reduction of the carbon impact of waste management, mostly due to the diversion of food waste from landfill and its recycling in anaerobic digestion. However, these carbon savings had limited impact on the global net emissions of municipal waste, due to the increase of the generated quantities over the same period, especially concerning textile waste.

Current recycling rates for plastic, metal, glass, and garden waste can be considered low to average, meaning that there is a potential to reduce the associated carbon emissions. However, the main potential for carbon emissions mitigation lies in waste prevention and re-use, especially for textile waste. Identifying actions to address textile waste generation and promoting its re-use is also believed to lead to significant savings.

The way forward

For Navarra, reducing by 25% its carbon footprint means moving from an estimated 713,000 tCO2eq to a total of 535,000 tCO2eq. For that, two strategies are possible:

• Reducing by 40% textile waste, 25% food waste, and 20% the other targeted materials (i.e., plastics, paper and cardboard, and healthcare waste, comprising mostly of sanitary textiles);
• Introducing a waste reduction target of 25% for all materials.

Efforts have been made on food waste recycling. Food waste generation decreased between 2016 and 2020 with positive impact on the total carbon footprint and pursuing this trend will also contribute to the reduction of climate emissions. In addition, currently, 44% of food waste is recycled in Navarra, while the rest is landfilled. This means that the region has a great opportunity to achieve high carbon savings by diverting these tonnages from landfilling to recycling. ACR+ and Zero Waste Scotland estimates that diverting 50% of food and garden waste from landfilling to recycling is expected to achieve carbon savings of 50,000 tonnes.

Considering their significant contribution to the overall carbon footprint, it is recommended to undertake a detailed investigation on the composition of food and textile waste as a follow-up activity to accurately quantify carbon impacts.

Navarra will continue to work on its carbon footprint of waste within the Interreg Europe LCA4Regions project. An outcome of this project is the development of an Action Plan which will consist in assessing the carbon footprint of the year 2016 and 2020 to compare it with the study already realised with the aim of analysing the evolution and implementing targeted measures to reduce the emissions.