Household Recycling
Project Drawdown defines household recycling as: the increased recovery of recyclable materials, not including paper nor organic materials, from the residential sector of the economy. This solution replaces the disposal of recyclable materials in landfills.
Recovering and recycling household waste materials for use in new products reduces the amount of materials manufactured from virgin sources, produces less greenhouse gas emissions, and reduces the environmental burden created if the waste is disposed in overcrowded landfills. Waste considered in this solution is post-consumer waste, measured at waste collection centers. [1] Recyclable waste types considered for this solution are metals, plastic, glass, and “other”. [2] Waste that is recyclable makes up around 37% of total municipal solid waste generated globally.
Methodology
Municipal solid waste is defined differently by governments, organizations, and researchers; for this solution, all sources include both household and commercial waste in aggregate values reported. Because the fraction of total waste allocated to households and commercial or industrial waste generators is not often reported, it is assumed that 50% of recyclable waste is derived from the industrial sector (US EPA, 1998).
Total Addressable Market [3]
The total addressable market for recyclable waste was calculated using a composite of forecasts, including a linear interpolation of World Bank data from 2010-2025, an extrapolation to extend those projections to 2050, and a per capita extrapolation using data from the Intergovernmental Panel on Climate Change (IPCC). [4] It is estimated that by 2050, global organic waste will be approximately 1459 million metric tons. Current adoption [5] of both household and commercial recycling at the year 2014 was estimated at 27% of recyclable waste (see Hoornweg and Bhada-Tata, 2012).
Adoption Scenarios [6]
Due to the lack of reliable future projections of the growth of recycling, three custom adoption estimates were developed based on increasingly ambitious recycling rates per region. [7] In the first estimate, all 2050 non-OECD regional rates are set to the 2014 OECD recycling rate of approximately 57%. In the second estimate, non-OECD countries’ recycling target rate for 2050 is set to the current Austrian recycling rate of 63%. In the third estimate, recycling rates for non-OECD countries, recycling rates in 2050 are set to correspond with the current best recycling rate of the country in the corresponding region. For example, Asia (sans Japan) region’s recycling rate target is set to 61%, which is Singapore’s recycling rate in 2015. From these estimations, adoption boundaries were created from which the Project Drawdown Scenarios were derived.
Impacts of increased adoption of industrial recycling from 2020-2050 were generated based on three growth scenarios, which were assessed in comparison to a Reference Scenario where the solution’s market share was fixed at the current levels.
- Plausible Scenario: Here, it is assumed that recycling will increase from present rates to 65% (pre-integration) of the market, [8] amounting to 941 million metric tons of recycled material in 2050, and 470.5 million metric tons allocated to household recycling.
- Drawdown Scenario: Here, the complete optimization of source separation and collection processes is assumed, as well as aggressive zero waste policy adoption. The amount of total recycled waste in 2050 is 984 million metric tons, with 492 million metric tons allocated to household recycling (89.65% of the post-integration market). This results in a mitigation impact of 6.05 gigatons of carbon dioxide-equivalent greenhouse gases.
- Optimum Scenario: This scenario considers the technical potential of the solution, assuming a “zero waste” world by 2060 which targets a nearly universal adoption of recycling. This results in 813.52 million metric tons of recycled waste in 2050 (99% of the post-integration market), with a mitigation impact of 5.8 gigatons.
Financial Model
Financial results were created by comparing the costs of creating and operating material recovery facilities or mechanical-biological treatment facilities to creating and operating sanitary landfills for an equivalent volume of recyclable waste. The cost of establishing new recycling facilities over the period in question is calculated to be US$2.4 trillion, [9] which is US$734 billion more than the cost of establishing new landfills. When revenues from recovered materials are included in comparison to the costs of virgin materials, however, operating recycling facilities costs less than operating landfills and sourcing virgin material feedstocks for industry.
Integration [10]
For integration into the Materials Sector, Drawdown first considers the reduction in recyclable waste due to the increased adoption of the assumed compostable fraction of bioplastic. The recyclable fraction of waste decreases year to year as the fraction of recyclable plastic used by humanity decreases, so that as the adoption scenarios become optimized the overall adoption of household recycling decreases yet the adoption percentage increases. Adoption peaks at 99% of the market in 2048 in the Optimum Scenario and holds constant for the rest of the period.
Results
In the Plausible Scenario, Drawdown found a potential 2.77 gigaton reduction in carbon dioxide-equivalent emissions over 2020-2050, corresponding to a 81% adoption of recycling of recyclable waste. This came with a net implementation cost of US$367 billion but a net operational savings over the same period of US$122 billion. For the Drawdown Scenario, the emissions avoided amount to 3.02 gigatons with a 90% adoption, and the Optimum Scenario results in 2.9 gigatons of emissions reduced at an 99% adoption by 2050.
Discussion
Household and industrial recycling are keystone elements of a circular economy that provides industry with feedstocks to produce needed goods with fewer emissions. Recycling also generates unmeasured benefits by extending the life of sanitary landfills and creating economic opportunity and activity in material recovery and reprocessing.
Limitations
The state of currently operating landfills and material recovery facilities could not be easily determined within the scope of this study. Because of the limitations to establish how much waste can be landfilled in currently operating landfills and how much of the capacity of currently operating material recovery facilities is not exploited to its full potential, first costs of such facilities are calculated for installing completely new facilities. Similar limitations of the study have been identified with establishing first costs of introducing new solid waste collection systems by municipalities, and the unused capacity of existing ones. Additionally, much of the complexity of recycling ceramics, rubber, textiles and e-waste have been oversimplified with the approach taken. Finally, it is also likely the development in the technologies of material recycling, product recycling and end-of-pipe technologies such as waste identification and sorting technologies, waste disassembly and shredding technologies, and material recovery technologies will have positive impacts on lowering first costs and operating costs of recycling.
[1] Pre-consumer waste is found in far smaller amounts: only 10% of total post-consumer waste generated by households, residential, commercial, and institutional subjects. Pre-consumer waste is also almost 100% recyclable on-site. The amount of pre-consumer waste that is lost from the material cycle is hence negligible (EU Joint Center 2002).
[2] Note “paper” is excluded and assessed by another Drawdown solution.
[3] For more on the Total Addressable Market for the Materials Sector, click the Sector Summary: Materials link below.
[4] Using UN 2015 median urban population forecast.
[5] Current adoption is defined as the amount of functional demand supplied by the solution in the base year of study. This study uses 2014 as the base year due to the availability of global adoption data for all Project Drawdown solutions evaluated.
[6] For more on Project Drawdown’s three growth scenarios, click the Scenarios link below. For information on Materials Sector-specific scenarios, click the Sector Summary: Materials link.
[7] Regions include: Organisation for Economic Co-operation and Development (OECD), Eastern Europe, Asia (sans Japan), Middle East & Africa, Latin America & Caribbean.
[8] Integration with other Drawdown solutions causes the TAM to decrease and the percentage adoption to increase. The adoption percentage of the Plausible Scenario post-integration is 81%.
[9] All monetary values are presented in US2014$.
[10] For more on Project Drawdown’s Materials Sector integration model, click the Sector Summary: Materials link below.
