Climate Mitigation Opportunities in the Planned Global Plastics Treaty

The use and production of plastic affect the climate in several ways over its life cycle. The plastic life cycle may be divided in four stages with differing climate impacts.

Table 1: Plastic Life Cycle Stages and Associated Climate Impacts
(High, moderate, or low)

Sources: Center for International Environmental Law. 2019. Plastic & Climate: The Hidden Costs of a Plastic Planet.; T. H. Christensen and T. Fruergaard. 2010. Recycling of Plastic, Chapter 5.3. In T. H. Christensen, ed. Solid Waste Technology & Management. Chichester: Wiley.; Ellen MacArthur Foundation. 2016. The New Plastics Economy: Rethinking the Future of plastics & catalyzing action.; and S-J Royer et al. 2018. Production of Methane and Ethylene from Plastic in the Environment. PLoS ONE. 13 (8)

Adopting circular economy best practices, combined with increased and effective waste management, provides the solution for decoupling plastic use from the consumption of finite resources and pollution to the environment. Climate mitigation opportunities in a circular plastic economy depends on the temporal scope and whether investments are for the short or longer term (10 years).

As a rule of thumb, the more plastic one can reduce or replace in a circular plastic economy over a longer period of the time, the greater the climate savings. In the short term, incineration with energy recovery may be a more climate-beneficial solution for plastic waste material that cannot yet be recycled and where the recovered energy substitutes fossil energy. But in the longer term, with new business models and design choices on for example, packaging, that increase reusability and recyclability; improved recycling technologies; and the transition to clean energy, incineration even with energy recovery will fall short of meeting global climate targets in reducing emissions.

Given the plastic treaty’s focus in addressing the full life cycle of plastics from source to sea, project opportunities are likely to revolve around developing and investing in circular plastic economy projects in the sectors that have the highest primary plastic production and waste generation.

Table 2: Global Primary Plastics Production and Primary Waste Generation
(In million metric tons, 2015)

Source: R. Geyer, J. Jambeck, and K. L. Law. 2017. Production, use, and fate of all plastics ever made. Science Advances. 3 (7).

Plastic pollution reduction options and technologies with climate impact reduction potential are under rapid development (Figure 1). However, there is no silver bullet solution. Ending plastic pollution requires a systematic response and a fundamental change in the way goods are made and used, as well as an accelerated decarbonization of the energy system (EMF 2021).

Figure 1: Options and Technologies for Plastic Pollution Reduction
(ranked according to climate impact reduction potential)

Source: Author.

Plastic waste prevention. Plastic waste prevention options can be from a product point of view, such as using less plastic in the product design (e.g., optimized thinner packaging). It can also be from a systemic point of view where the business model itself is waste-preventive, as is the case when a multiuse product or packaging replaces a single-use product or packaging, or when the lifetime of a product is prolonged through repair or design choices. A series of life cycle assessment studies conducted by the United Nations Environment Programme (2021) on single-use plastics and their alternatives concluded that the more times a product can be used, the lower the environmental impact of that product.

High- and low-quality recycling. High-quality recycling is when recycled materials can substitute virgin plastic materials of similar quality, thus allowing for consecutive use or consumption loops of the plastic material. With an increasing focus from industry and national plastic strategies on achieving higher recycling rates and higher quality of the recycled plastic, innovations in plastic recycling include renewed chemical recycling, which breaks down plastic into monomers for use by refineries and chemical producers.

Renewed interest in chemical recycling is linked to the prospects of recreating the original properties of the plastic material. This is in contrast to mechanical recycling or material recycling, where collected plastic waste undergoes shredding, melting, or granulation and where the chemical structure is maintained, but also where quality often deteriorates, except for closed loop systems, such as bottle-to-bottle collection and recycling. Currently, chemical recycling is only capable of recycling polymer types that are already mechanically recyclable. It has very high energy requirements and should be secondary to mechanical recycling.

Low-quality recycling is using recycled plastic as a substitute for non-plastic materials (e.g., cotton, concrete, or wood) in production, or recycling plastic into a product that cannot be recycled afterwards. In these cases, the environmental benefits from plastic recycling will be small or nonexistent. Novel production and recycling technologies need time to develop and scale up before they can perform at the same standard or better than established large-scale technologies (United Nations Environment Programme, 2021).

Controlled landfilling and urban mining. Controlled landfilling may be defined as a landfill where there is no risk that the plastic waste can catch fire and emit greenhouse gases. It is possible to begin urban mining of landfilled plastics, but it is unlikely that the recycled material will be able to substitute for virgin plastic material. It is more likely to be used as fuel.

Thermal treatment with and without energy recovery and substitution of fossil fuels. If energy is recovered in the process, thermal treatment or incineration of waste that cannot yet be recycled could potentially have climate benefits in the short term. These are not long-term solutions because incineration and thermal treatment (both with and without energy recovery) would consume too much of the remaining carbon budget in 2050, undermine global efforts to keep warming below 1.5°C, and make even a 2°C target nearly impossible (Center for International Environmental Law, 2019).

Chemical recycling and pyrolysis. Plastic waste can be converted back into feedstock for the chemical industry for products that have the same properties as those manufactured from fossil feedstock. It can potentially be used to produce new plastic materials. Pyrolysis is a form of chemical recycling that generates products like gas, tar, and char that can be refined for use in diesel fuels, gasoline, or heating oils (Ocean Conservancy, 2022).

The climate impacts of chemical recycling or pyrolysis of plastic waste depend on the energy balance of the processes, as well as what the resulting product substitutes and to what degree. If the resins or carbon products substitute virgin plastic materials, the climate benefits will be higher than if the products were used as substitute for fuel or released back into the atmosphere (e.g., as part of a production process).

Bioplastics and plastic alternatives. There is an increasing trend toward replacing conventional fossil-based plastics with bioplastics, which may be biodegradable or derived partly or fully from biomass. However, this does not solve many of the problems and may create new ones (Haut et al, 2017). Replacing one single-use or disposable plastic product with another made of a different material (e.g., paper, bio-based, biodegradable plastics) is likely to transfer the burdens and create other problems. Manufacturers of single-use products should instead shift their focus toward the production of more circular commodities (UNEP, 2021).

Carbon finance is an innovative environmental funding tool that places a financial value on emissions and allows the purchase of carbon credits from sustainable projects that result in emission reductions. The key criteria that make projects eligible for carbon trading are additionality and proof that emission reductions would not have occurred under a business-as-usual scenario (UNHCR, 2014). Since the carbon financing mechanism is not fully in place under the Paris Agreement, climate mitigation and plastic reduction projects need to be financed by bilateral donors and global investment banks, public equity funds, corporate bonds, and private market funds that are increasingly focusing on the circular economy as well as extended producer responsibility and plastic credits.

Extended Producer Responsibility (EPR) is seen as both a legal framework or policy to introduce mandatory collection targets and as a financing mechanism for waste collection, sorting, and recycling. In short, EPR holds producers (brands, importers, and manufacturers) financially responsible for end-of-life management of their products or packaging. As a policy tool, it puts the cost of waste management and pollution on the producers, which means that governments do not need to finance waste management infrastructure or collect waste management fees from households. It mobilizes the necessary financing for waste management but also creates a financial incentive for producers to minimize wastes and design their products and packaging in such a way that makes recycling cost-efficient.

In Asia, some countries have mandatory EPR schemes for packaging, while others only recently adopted or proposed legislation for voluntary initiatives. For example, Japan, the Republic of Korea, Singapore, and Viet Nam have either mandatory EPR on packaging in effect or the EPR framework passed. Indonesia; Hong Kong, China; Malaysia; the People’s Republic of China; and the Philippines have mandatory EPR legislation on packaging emerging, with Indonesia and Malaysia already having voluntary EPR on packaging (World Bank, 2022).

Plastic crediting functions like the carbon credit market and creates a market or plastic credit mechanism that drives investments into recycled plastic procurement and plastic collection or recycling projects. Plastic credit sales generate capital for plastic waste projects such that for every credit bought, an additional one tonne of plastic is collected or recycled (Zinnes, 2021).

Various unofficial plastic credit programs have existed since 2017. In 2021, Verra, operator of the world's largest registry of carbon credits, introduced the Plastic Waste Reduction Standard (the Plastic Standard) to provide a credible way to compensate for plastic pollution, establish best practices, and vet projects to ensure these meet the required plastic collection and recycling targets. The Plastic Standard is considered complimentary to the Guidelines for Corporate Plastic Stewardship, which enables companies to assess their plastic footprint, identify actions within their value chains (such as by designing materials for recyclability and reuse and increasing recycled content) to reduce their footprint, and increase collection efforts to keep their plastic materials in the plastic value chains.

Guidelines for Corporate Plastic Stewardship – February 2021.

Center for International Environmental Law. 2019. Plastic & Climate: The Hidden Costs of a Plastic Planet.

Ellen MacArthur Foundation (EMF). 2016. The New Plastics Economy: Rethinking the Future of Plastics & Catalysing Action.

EMF. 2021. Completing the Picture: How the Circular Economy Tackles Climate Change (2021 Reprint).

G. Haut et al. 2017. Bioplastics in a Circular Economy: The Need to Focus on Waste Reduction and Prevention to Avoid False Solutions.

Material Economics. 2018. The Circular Economy – A Powerful Force for Climate Mitigation.

Ocean Conservancy. 2022.Chemical Recycling Policy Position.

Organisation for Economic Cooperation and Development. 2022. Global Plastics Outlook: Economic Drivers, Environmental Impacts and Policy Options. Paris: OECD Publishing.

R. Geyer, J. Jambeck, and K.L. Law. 2017. Production, Use, and Fate of All Plastics Ever Made. Science Advances. 3 (7).

S-J. Royer et al. 2018. Production of Methane and Ethylene from Plastic in the Environment. PLoS ONE. 13 (8).

T.H. Christensen and T. Fruergaard. 2010. Recycling of Plastic, Chapter 5.3. In T. H. Christensen, ed. Solid Waste Technology & Management. Chichester: Wiley.

T. Zinnes. 2021. Your Roadmap to the Global Plastic Credit Market. Plastic Collective. 19 March.

United Nations Environment Programme. 2021. Addressing Single-use plastic products pollution using a life cycle approach. Nairobi: United Nations Environment Programme.

UNHCR. 2014. Carbon Financing.

World Bank. 2022. The Role of Extended Producer Responsibility Schemes for Packaging towards Circular Economies in APEC. Washington, DC: World Bank.

World Economic Forum. 2016. The New Plastics Economy, Rethinking the future of plastics. Geneva: World Economy Forum.