This chapter introduces a Climate Mitigation scenario involving a global carbon tax and decarbonisation of the global power sector. With the fossil-based nature of plastics fundamentally linked to climate change, the aim is to better understand the interlinkages between plastics and climate mitigation policies and to provide insights into synergies and trade-offs between the two policy areas. The chapter compares the effects on greenhouse gas emissions of the Global Ambition scenario presented in Chapter 8 and of the Climate Mitigation scenario, and then looks at the emissions and economic impacts of combining the two in a joint Global Ambition and Climate Mitigation scenario.
Global Plastics Outlook
Policy Scenarios to 2060
9. Interactions between plastics and climate mitigation policies
Abstract
Key messages
The plastics lifecycle is fundamentally linked to climate change. Plastics are largely derived from fossil fuels, and plastics production and waste management both use energy and thus lead to greenhouse gas (GHG) emissions.
In addition to significantly reducing plastic leakage (its primary objective), the Global Ambition scenario (presented in Chapter 8) is also projected to reduce plastics lifecycle GHG emissions in 2060 by 2.1 gigatonnes of carbon dioxide equivalent (Gt CO2e), namely 50% below the Baseline scenario. This reduction is mostly due to the strong decrease in plastics use.
The Climate Mitigation scenario has as its primary objective the reduction of GHG emissions. Through a global carbon tax and decarbonistion of the power sector, it is projected to reduce global GHG emissions in 2060 by around one-third below Baseline levels, corresponding to a level of global gross emissions of 63 Gt CO2e. While the effects on plastics use are limited, the Climate Mitigation scenario slightly increases the share of secondary (recycled) plastics by increasing the price of fossil fuel inputs for primary plastics production.
Combining plastics and climate mitigation policies fully exploits the complementarity of the two environmental policy domains. The Global Ambition and Climate Mitigation scenario is projected to decrease plastics lifecycle GHG emissions by 67% from Baseline levels in 2060 (from 4.3 Gt CO2e to 1.4 Gt CO2e, which is lower than 2019 emissions levels). While plastics policies mainly mitigate plastics lifecycle GHG emissions by reducing plastics use and waste generation, climate change mitigation policies further reduce GHG emissions by improving the GHG-intensity of both plastics production and waste management.
Flanking policies are necessary to prevent any emissions trade-off between plastics policies and climate change in waste management. Waste management GHG emissions could increase if recycling replaced sanitary landfilling. If recycling replaced incineration, the impact on GHGs would depend on the use of waste-to-energy processes and the carbon intensity of the energy that this process would replace.
9.1. Climate mitigation policies complement policy action on plastics
The plastics lifecycle is fundamentally linked to climate change in many, and sometimes opposing, ways. Plastics contribute to climate change because greenhouse gases (GHGs) are emitted throughout their lifecycle – from production to their end of life (see Chapter 6). In some instances, there are clear synergies between plastics and climate mitigation policies, for example, when they lead to more efficient use of resources in the economy. In other cases, there are trade-offs, such as plastic waste management, where recycling leads to GHG emissions. Therefore, the interactions between plastics and climate mitigation policies warrants a broad approach in which policies work together to exploit synergies and overcome the trade-offs.
This chapter introduces a Climate Mitigation scenario to understand better the interlinkages between plastics and climate mitigation policies and to provide insights into relevant synergies and trade-offs between the two policy areas. This scenario is considered individually, and in combination with the Global Ambition scenario on plastics, presented in Chapter 8 (the Global Ambition and Climate Mitigation scenario).
The climate mitigation policies modelled in these scenarios target a decarbonisation of all sectors of the global economy. This would see global GHG emissions in 2060 around one-third lower than the levels projected in the Baseline scenario for 2060, corresponding to a level of global gross emissions of 63 gigatonnes of carbon dioxide equivalent (Gt CO2e).1 There are two main interactions between plastics and climate:
Plastics production and waste management use energy. GHG emissions related to plastics production depend on the type of plastics produced – the emissions from producing and converting 1 tonne of primary plastics may vary from 2.7 to 6.3 t CO2e depending on the polymer involved, as well as on the energy used to produce plastics and the electricity mix of the country where plastics are produced. This is also the case for waste recycling, which uses energy to convert plastic waste to secondary plastics.
Fossil fuels are the main feedstock in plastics production. As fossil fuels are used as feedstock in the production of primary plastics, plastics production is inevitably interlinked with fossil fuel markets. An increase in demand for fossil inputs by the plastics sector leads, all things being equal, to an increase in fossil fuel prices, which in turn affects fossil fuel combustion and GHG emissions in other sectors. Conversely, any increase in fossil fuel prices, whether induced by climate mitigation policies or not, increases the relative price of fossil-based plastics, hence decreasing their production and related GHG emissions (see Box 6.1 in Chapter 6). Changes in the demand for primary plastics also affect the demand for other types of plastics, such as secondary (recycled) and biobased plastics, with consequent changes in GHG emissions.2
The Climate Mitigation scenario analyses these interactions in detail by modelling the impact of major decarbonisation instruments: carbon pricing and the structural transformation of the power sector (Table 9.1 and Annex B).3 In this scenario, carbon pricing curbs GHG emissions from fossil fuel combustion in the whole economy, including households and all sectors, while the structural transformation of the power sector reduces a large share global GHG emissions thanks to the deployment of low-GHG power generation technologies.4
Table 9.1. Description of the Climate Mitigation scenario
Note: More details on the assumptions are provided in Annex B.
When plastics and climate mitigation policies are implemented jointly (Global Ambition and Climate Mitigation scenario), two more interlinkages are taken into account:
The sectoral demand for plastics responds to changes in plastics prices. Sectors that require plastic as an input also require energy and sometimes generate GHG emissions from other sources. Hence, any change in plastics prices triggers substitutions and change these sectors emissions. The plastics content of the goods produced by these sectors may also influence the amount of energy involved in using them (e.g. by influencing the weight), hence changing greenhouse gas emissions from the use-phase of such goods. In addition, the sectors providing alternatives to plastics as inputs (e.g. aluminium, glass, etc.) also demand energy and sometimes generate process GHG emissions. Consequently, any substitution towards these alternatives also has implications for overall greenhouse gas emissions.
GHG emission intensity varies across waste management techniques. The use of plastics leads to waste, which in turn contributes to GHG emissions. Of the various end-of-life fates of plastics, incineration emits the most greenhouse gases (2.3 tCO2e per tonne of plastics on average). Some of these emissions might be offset if energy is recovered through waste-to-energy processes, but the mitigation potential heavily depends on a country’s electricity generation mix (OECD, 2022[1]). Recycling and subsequent production of secondary plastics produces on average 0.9 tCO2e per tonne of plastics, which is less than is emitted from the primary plastics production process. On balance, the switch to secondary plastics production can help to reduce GHG emissions if a region’s GHG intensity of recycling is low enough (considering a global average GHG intensity of recycling and depending per polymer, at least 1.8 tCO2e per tonne of primary plastics replaced by secondary can be abated). Sanitary landfilling is the least GHG‑intensive end-of-life fate for plastics, at 0.1 t CO2e per tonne of plastics.
Other interlinkages between plastics and climate mitigation policies could not be taken into account in the OECD ENV-Linkages model. For example, recent research by Royer et al. (2018[2]) based on experimental data shows that plastic leakage to the environment also has an impact on GHG emissions. The annual global methane emissions due to uncontrolled plastic degradation in the environment are estimated to be roughly 2 Mt CO2e (Shen et al., 2020[3]). Furthermore, emerging studies suggest that plastics in the environment exacerbate the impacts of climate change on wildlife and ecosystems (Ford et al., 2022[4]). In the ocean, plastics may reduce the photosynthetic efficiency of marine phytoplankton and affect ocean carbon sequestration (Shen et al., 2020[5]). In addition, the presence of microplastics may be a further stressor in highly fragile ecosystems such as the Polar Regions, where they may potentially decrease the capacity of the surface to reflect solar radiation, thus accelerating melting (Evangeliou et al., 2020[6]).
Overall, these climate scenarios are tailored to be ambitious yet not overly disruptive. The scenarios focus on the interaction mechanisms, and do not intend to contribute directly to the discussion of a transition to a “net-zero economy”. Doing so would require a more comprehensive analysis of the implications for energy demand of plastics use in products in the use phase, as well as a quantification of the many disruptions to economic structures and production strategies stemming from full decarbonisation. For example, the modelling analysis would need to be able to quantify more precisely substitutions away from conventional fossil-based plastics to low-carbon alternatives, including the impacts of bioplastics on land-use change and corresponding carbon sequestration (see Chapter 6), as well as the plastics requirements specific to low-carbon transition technologies. Although some very recent work is beginning to tackle these issues regionally – such as by SYSTEMIQ (2022[7]) for Europe – there is not yet enough information for a detailed global assessment.
9.2. The Global Ambition scenario contributes to climate change mitigation but only limitedly
To better understand the interactions between plastics and climate mitigation policies, it is useful to first identify channels through which plastics policies can affect greenhouse gas emissions. The primary objective of the Global Ambition scenario is to virtually eliminate plastic leakage to the environment and; none of the policies in the scenario aim directly at reducing GHG emissions from plastics lifecycle (see Chapter 8). Nevertheless, the policies in this scenario influence GHG emissions by changing the amount and structure of plastics use and the end-of-life fates of plastics. Furthermore, plastics policies affect plastics production processes, for which fossil fuel input and energy use play an important role. Overall, the Global Ambition scenario reduces these emissions by 2.1 Gt CO2e (far right bar in Figure 9.1) compared to the Baseline (far left bar), which corresponds to a 50% decrease in plastics lifecycle GHG emissions compared to the Baseline in 2060.
These GHG emission reductions result from various factors (Figure 9.1),5 but the factors with the greatest impact are decrease in plastics use (second bar) and waste generation (third bar). This “volume” effect amounts to a reduction in global plastics lifecycle GHG emissions of around 2.3 Gt CO2e in 2060, of which 2.1 Gt is due to the decrease in plastics use (the Global Ambition scenario leads to a reduction of plastics use by around 400 Mt; see Chapter 8), compounded with the shift to secondary plastics.
All other factors, including the composition of waste and changes in the GHG intensity of plastics production and waste, have an impact of one order of magnitude below the “volume” effect, and tend to increase GHG emissions. In the Global Ambition scenario, the share of more GHG-intensive polymers such as fibres increases, as well as the share of more GHG-intensive end-of-life fates, notably recycling. The policies in this scenario also slightly increase the GHG intensity of plastics production and end of life. These effects come from the role of plastics in fossil fuel markets: with a decrease in fossil fuel demand due to the Global Ambition scenario, global fossil fuel prices tend to decrease slightly, leading to lower relative prices of GHG-intensive products (e.g. fibres) compared to others. The plastics policies also result in a higher demand for fossil fuels for energy in economic activities, which include plastics production and recycling.
Figure 9.1. The Global Ambition scenario is projected to halve plastics lifecycle GHG emissions, mainly by reducing volumes of plastics use
Note: This waterfall chart depicts the plastics lifecycle GHG emissions in the Baseline (far left bar) and Global Ambition (far right bar) scenarios. The other bars show the contributions of the various drivers to the change in plastics lifecycle emissions between this scenario and the Baseline. Production refers to the emissions generated from production of raw polymers while conversion refers to the emissions from their conversion to plastics products. Waste refers to emissions from their end of life (incinerated, recycled or landfilled plastics). The details of the driver bars are as follows (from left to right, see Annex A for details):
1. “Volume (Prod.)” shows the change in emissions from total plastics use, assuming Baseline emission factors and composition.
2. “Volume (Waste)” shows the change in emissions from total plastic waste generated, assuming Baseline emission factors and composition.
3. “Polymer composition” adds the effect of the projected change in plastics use composition.
4. “Waste composition” adds the effect of the projected change in the composition of end-of-life fates, including the shift between primary and secondary plastics and the changes in incineration (without accounting for waste-to-energy processes impacts).
5. “GHG intensity” adds the changes in emission factors (due to the changes in the production structure in ENV-Linkages), both for production and conversion (“Prod.”) and waste (“Waste”).
Source: OECD ENV-Linkages model.
Of the three pillars of the Global Ambition (see Chapter 8), restraining demand for plastics mitigates the most greenhouse gas emissions, closely followed by enhancing recycling (Figure 9.2, Panel A). This is because the bulk of the emissions increase in the Baseline is due to the increase in plastics use (Chapter 6) and these pillars directly target the consumption and production of plastics products through taxes or extending product lifespans. However, part of the GHG mitigation from waste management induced by the enhancing recycling pillar is offset by the increase in recycling to replace sanitary landfilling and mismanaged waste, which are less emissions intensive.6 Finally, closing leakage pathways has very limited impact on plastics lifecycle GHG emissions.
These results emphasise that the climate change mitigation potential of plastics policies mostly lies in decreasing plastics demand (both primary and secondary), while the structure and technology of production and waste management only play a minor role. As highlighted in OECD Global Plastic Outlook: Economic Drivers, Environmental Impacts and Policy Options (OECD, 2022[1]), a more precise conclusion on this issue demands a closer look at the GHG impact of potential substitutions of plastics by other products and materials, and the impact of plastics policies on other sectors of the economy.
The policies in the Global Ambition scenario also affect total GHG emissions (Figure 9.2, Panel B) – not just emissions from the plastics lifecycle. Changes in global GHG emissions respond to very different drivers compared to plastics-related emissions: plastics-related emissions are concentrated in a few economic sectors and do not necessarily represent a large percentage of these sectors’ GHG emissions, while global GHG emissions take all sectors into account. Global GHG emissions changes result from changes in economic activity and in the average GHG-intensity of economic activity, which reflects policy-induced changes in sectoral production. If the decrease in plastics use was strongly compensated for by the use of more GHG-intensive materials, global emissions could increase. This is fortunately not the case, as changes in global GHG emissions in the Global Ambition scenario are projected to be –0.8 Gt CO2e (–0.8%) below Baseline emissions in 2060.
This reduction in global GHG emissions is larger than the reduction in economic activity (–0.7%, as shown in Figure 9.7). This reveals small positive climate-related spillovers of the plastics policies on other sectors of the economy, which imply that plastics policies do not trigger large substitution by more GHG-intensive materials. They also do not seem to significantly increase emissions from the use of plastics products which are not included in plastics lifecycle emissions (e.g. from replacing plastics in car production with heavier materials, which increase car weight and therefore GHG emissions). This result therefore shows that plastics policies are an effective way to reduce plastics lifecycle GHG emissions.7
As for plastics lifecycle GHG emissions, restraining demand is the largest contributor to global GHG emission reductions. Enhancing recycling and closing leakage pathways increase global emissions, but by a much smaller order of magnitude than reducing demand. Interestingly, closing leakage pathways has a larger effect on total GHG emissions than on plastic lifecycle emissions. While the direct effects on plastics production and on the amounts of plastics recycled or incinerated are limited, the investments included in this pillar change the sector allocation of value added towards waste management and construction activities (see Chapter 8) to the detriment of other activities; these effects results in a small increase in total GHG emissions.
Figure 9.2. Restraining plastics demand contributes the most to emissions reductions
Note: Plastics lifecycle GHG emissions correspond to GHG emitted throughout plastics lifecycle, while Total GHG emissions refer to all GHG emitted globally by all sectors and agents.
Source: OECD ENV-Linkages model.
9.3. The joint Global Ambition and Climate Mitigation scenario decreases plastics lifecycle greenhouse gas emissions
9.3.1. Climate mitigation policies alone have little impact on plastics use
Although not specifically focused on the plastics sector, the Climate Mitigation scenario is projected to reduce plastics use by 34 million tonnes (Mt) by 2060, and by 24 Mt if implemented jointly with the Global Ambition scenario (Figure 9.3). These reductions in plastics use are small compared to the overall amount of plastics use projected to 2060, which is 1 231 Mt in the Baseline, and compared to the decrease in plastics use in the Global Ambition scenario (around 403 Mt). This is because the policies in the Climate Mitigation scenario do not address plastics production directly, and only influence it through carbon pricing and electricity prices, which in turn have an effect on plastics production prices and on the energy mix used to produce plastics. Compared to the USD 1 000 per tonne tax on plastics in the Global Ambition scenario, the world average carbon price of USD 69 per tonne of CO2 in the Climate Mitigation scenario translates into only USD 241 per tonne of plastics (using the 2060 average baseline CO2 intensity). Meanwhile, the taxes on plastics use are also complemented by other policies in the Global Ambition scenario.
Figure 9.3. The Climate Mitigation scenario alone has limited impact on global plastics use
Source: OECD ENV-Linkages model.
Despite having little effect on total global plastics use, the climate mitigation policies do influence the structure of plastics use, especially the balance between primary and secondary plastics (Figure 9.4). The Climate Mitigation scenario is projected to decrease both primary and secondary plastics production, because both production technologies demand energy. However, primary plastics production is more affected than secondary production because primary production is more energy-intensive. This results in a further increase in the share of secondary plastics in total plastics production when the climate mitigation policies are implemented alone. When climate mitigation policies are combined with plastics policies in the Global Ambition and Climate Mitigation scenario, the share of secondary plastics in total plastics use does not increase as much as with climate mitigation policies alone. This is because secondary plastics also have a sizable GHG emission profile.
Figure 9.4. The Climate Mitigation scenario reduces primary plastics more than secondary plastics
Source: OECD ENV-Linkages model.
9.3.2. A combined policy package reduces plastics lifecycle GHG emissions significantly
The policies in the Climate Mitigation scenario have a significant impact on plastics lifecycle GHG emissions (Figure 9.5), decreasing them by 1.3 Gt CO2e in 2060 compared to Baseline (a fall of 31%). The combined Global Ambition and Climate Mitigation scenario reduces plastics lifecycle GHG emissions even more – by 2.8 Gt CO2e in 2060 (a decrease of 67%), falling to 1.4 Gt CO2e, which is even lower than 2019 emissions levels.
Figure 9.5. The Global Ambition and Climate Mitigation scenario reduces plastics lifecycle GHG emissions to below 2019 levels
Source: OECD ENV-Linkages model.
The main channel through which the Climate Mitigation scenario affects plastics lifecycle GHG emissions is a shift of energy use in plastics-related activities (production and conversion, and to a lesser extent end of life) from more to less carbon intensive sources, such as electricity and gas. This is the case whether the Climate Mitigation scenario is implemented alone (Panel A in Figure 9.6) or jointly with Global Ambition (Panel B). This shift in energy use towards less GHG-intensive sources is driven both by carbon pricing, which reduces the share of fossil energy, and the structural transformation of the power sector, which reduces indirect GHG emissions from electricity generation. Recycling is the only disposal option that is affected by carbon pricing – because GHG emissions from incineration are mostly direct emissions and not related to energy use, and because emissions from sanitary landfilling are very low. Carbon pricing leads to a decrease in recycled plastics, but given that the recycling sector is not very GHG-intensive, the decrease is limited. This is why the end-of-life contribution to GHG mitigation is limited. Polymer and waste composition do not contribute to the mitigation effort, but this might be due to a limitation of the ENV-Linkages model, which does not differentiate GHG intensity of polymers due to the lack of information on the cost structures of different polymers, preventing any polymer-specific impact of climate mitigation policies.
Figure 9.6. The policies in the Climate Mitigation scenario mainly reduce the GHG intensity of plastics production
Note: This waterfall chart depicts the plastics lifecycle GHG emissions in the scenarios without climate mitigation (far left bar) and the same scenario with climate mitigation (far right bar). The other bars show the contributions of the various drivers to the change in plastics lifecycle GHG emissions between the scenarios with climate change mitigation and those without climate change mitigation. Production refers to the emissions generated from production of raw polymers, while conversion refers to the emissions from their conversion to plastics products. Waste refers to emissions from their end of life (incinerated, recycled or landfilled plastics). The details of the driver bars are as follows (from left to right, see Annex A for details):
1. “Volume (Prod.)” shows the change in emissions from total plastics use, assuming Baseline/Global Ambition emission factors and composition.
2. “Volume (Waste)” shows the change in emissions from total plastic waste generated, assuming Baseline/Global Ambition emission factors and composition.
3. “Polymer composition” adds the effect of the projected change in plastics use composition.
4. “Waste composition” adds the effect of the projected change in the composition of end-of-life fates, including the shift between primary and secondary plastics and the changes in incineration (without accounting for waste-to-energy processes impacts).
5. “GHG intensity” adds the changes in emission factors (due to the changes in the production structure in ENV-Linkages), both for production and conversion (“Prod.”) and waste (“Waste”).
Source: OECD ENV-Linkages model.
Climate change mitigation policies and plastics policies therefore influence plastics lifecycle GHG emissions through different channels – the GHG intensity of plastics production for the former (Figure 9.6), and the decrease in plastics use for the latter (Figure 9.1). This means that the two sets of policies have synergies for maximising the mitigation of plastics lifecycle GHG emissions.
Looking beyond plastics lifecycle GHG emissions, the Climate Mitigation scenario reduces global GHG emissions by 31.6 Gt CO2e in 2060, which corresponds to a 33% reduction (Figure 9.7, Panel B), which is its primary objective. The plastics policies in the Global Ambition scenario have limited effects on GHG emissions, with an overall reduction of 0.8 Gt CO2e (Section 9.3), while the Global Ambition and Climate Mitigation scenario reduces global GHG emissions by 32.1 Gt CO2e. The overall effects of the two sets of policies on global GHG emissions are greater than the sum of their parts, showing that plastics and climate mitigation policies are highly complementary. However, climate mitigation policies cannot be used as a substitute for plastics policies to reduce plastic leakage (as shown in Section 9.3.1), and plastics policies cannot replace dedicated climate mitigation action.
9.3.3. The economic effects of combining Global Ambition with Climate Mitigation highlight their complementarity
Since reducing greenhouse gas emissions is the primary objective of climate mitigation policies, they are more cost-effective than plastics policies in achieving this goal (Panel A in Figure 9.7). The cost of the policies in the Climate Mitigation scenario is projected to amount to a 2.2% reduction of GDP in 2060, and reduces GHG emissions by 33%. On its own, the Global Ambition scenario reduces GDP by 0.7%, and GHG emissions are reduced by 0.8% as an incidental effect. Thus, climate mitigation policies are a more cost efficient way to abate emissions. This is normal, because the climate mitigation policies target the whole economy, while plastics policies only target the plastics sector. However, GHG emission reductions are not the primary goal of plastics policies, and they provide other important environmental benefits, not least reducing plastic leakage to the environment (Chapters 7 and 8).
The cost of climate mitigation policies is not significantly affected by the presence of plastics policies. The GDP impact of climate mitigation policies, whether taken alone or on top of the impacts of plastics policies, is around –2.2% of GDP compared to the Baseline in both cases. Ultimately, at the global level, the policies in the two scenarios are complementary, because the cost of the joint plastics and climate scenario (Global Ambition and Climate Mitigation) is very close to the sum of the costs of the two individual scenarios. This emphasises the fact that the synergies between plastics and climate mitigation policies mostly lie in the plastics sector itself.
Figure 9.7. The GDP and emissions effects of climate and plastics policies are greatest when they are combined
Source: OECD ENV-Linkages model.
References
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Notes
← 1. This reduction in global GHG emissions is not sufficient to achieve the Paris Agreement goals of limiting global temperature increase to well below 2°C, and possibly 1.5°C. However, the scenario is still useful for illustrating the impact of climate change policies on plastics and the potential synergies with plastics policies.
← 2. Secondary plastics use less energy in production, but the recycling process needed to create scrap material is associated with significant GHG emissions. The production of primary biobased plastics involves less direct emissions than fossil-based plastics production. However, the overall effects, taking into account potential land-use change, are ambiguous, and depend on the biomass production techniques and the amount of deforestation that could be triggered by biobased plastics production increases (as analysed in detail in Section 6.1.2 in Chapter 6).
← 3. Both instruments are calibrated relying on information from the sustainable development scenarios (SDS) of the 2018 World Energy Outlook (WEO) (International Energy Agency, 2018[8]). Overall, this scenario represents a moderate climate mitigation ambition, since it reduces GHG emissions by around a third by 2060 (see Section 9.2.3).
← 4. The two instruments are modelled jointly in the OECD ENV-Linkages model. The model includes a detailed representation of the power sector with different technologies; and mitigation options for firms and households by allowing for substitution between fuels in the different firms’ production function and households’ utility function. The model has been updated to include the production structure and end-of-life fates of both primary and secondary plastics, and to adopt a lifecycle approach to the GHG emissions attributable to plastics (see Annex A). As a global general equilibrium model, ENV-Linkages is also able to capture the rich interlinkages between sectors and regions. As such, it is particularly fit to explore interactions between climate change mitigation policies and plastics policies. However, limitations in data availability and the model structure mean that the assessment does not include the land-use change impacts of bioplastics production, or the possible mitigation potential of waste to energy. These are minor gaps, as the Global Ambition scenario does not include a transition to bioplastics, and the mitigation potential of waste-to-energy electricity generation is still subject to debate.
← 5. More details on the methodology to analyse the effects that lead to changes in emissions are provided in Annex A.
← 6. This effect might be over- or under-estimated depending on the share of waste incinerated using waste-to-energy processes, and the electricity mix of the country where this incineration occurs.
← 7. The magnitude of the emission reductions due to plastics policies would also need to be confirmed by more fine-grained analysis of substitution effects, as the modelling of these substitutions in the ENV-Linkages model is only implemented at an aggregate sector level.