Editing IPCC:AR6/WGIII/Chapter-10 (section)

== 10.8 Enabling Conditions ==

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=== 10.8.1 Conclusions Across the Chapter ===

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This final section draws some conclusions from the chapter and provides an overview-based feasibility assessment of the major transport mitigation options, as well as a description of emerging issues. The section ends by outlining an integrated framework for enabling the transformative changes that are emerging and required to meet the potential transformative scenarios from [[#10.7|Section 10.7]] .

Transport is becoming a major focus for mitigation as its GHG emissions are large and growing faster than those of other sectors, especially in aviation and shipping. The scenarios literature suggests that without mitigation actions, transport emissions could grow by up to 65% by 2050. Alternatively, successful deployment of mitigation strategies could reduce sectoral emissions by 68%, which would be consistent with the goal of limiting temperature change to 1.5°C above pre-industrial levels. This chapter has reviewed the literature on all aspects of transport and has featured three special points of focus: (i) a survey of lifecycle analysis from the academic and industry community that uses these tools; (ii) surveying the modelling community for top-down and bottom-up approaches to identify decarbonisation pathways for the transport sector, and (iii) for the first time in the IPCC, separate sections on shipping and aviation. The analysis of the literature suggests three crucial components for the decarbonisation of the transport sector: demand and efficiency strategies, electromobility, and alternative fuels for shipping and aviation.

The challenge of decarbonisation requires a transition of the socio-technical system, which depends on the combination of technological innovation and societal change ( [[#Geels--2017|Geels et al. 2017]] ). A socio-technical system includes technology, regulation, user practices and markets, cultural meaning, infrastructure, maintenance networks, and supply networks ( [[#Geels--2005|Geels 2005]] ) (Cross Chapter Box 12 in Chapter 16). The multi-level perspective (MLP) is a framework that provides insights to assist policymakers when devising transformative transition policies ( [[#Rip--1998|Rip and Kemp 1998]] ; [[#Geels--2002|Geels 2002]] ). Under the MLP framework, strategies are grouped into three different categories. The Micro level (niche) category includes strategies where innovation differs radically to that of the incumbent socio-technical system. The niche provides technological innovations a protected space during development and usually requires considerable R&amp;D and demonstrations. In the Meso level (regime) state, demonstrations begin to emerge as options that can be adopted by leading groups who begin to overcome lock-in barriers from previous technological dependence. Finally, in the Macro level (landscape) stage, mainstreaming happens, and the socio-technical system enables innovations to break through. Figure 10.22 maps the MLP stages for the major mitigation strategies identified in this chapter.

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[[File:7e68c42701cd3beee0e92de7bac2caea IPCC_AR6_WGIII_Figure_10_17.png]]

'''Figure 10.22 | Mitigation options and enabling conditions for transport.''' Niche scale includes strategies that still require innovation.

'''Demand and behaviour''' . While technology options receive substantial attention in this chapter, there are many social and equity issues that cannot be neglected in any transformative change to mitigate climate change. Transport systems are socio-economic systems that include systemic factors that are developing into potentially transformative drivers of emissions from the sector. These systemic drivers include, for example, changes in urban form that minimise automobile dependence and reduce stranded assets; behaviour change programmes that emphasise shared values and economies; smart technologies that enable better and more equitable options for transit and active transport as well as integrated approaches to using autonomous vehicles; new ways of enabling electric charging systems to fit into electricity grids, creating synergistic benefits to grids, improving the value of electric transit, and reducing range anxiety for EV users; and new concepts for the future economy such as circular economy, dematerialisation, and shared economy that have the potential to affect the structure of the transport sector. The efficacy of demand reduction and efficiency opportunities depends on the degree of prioritisation and focus by government policy. Figure 10.22 suggests that innovative demand and efficiency strategies are at the regime scales. While these strategies are moving beyond R&amp;D, they are not mainstreamed yet and have been shown to work much more effectively if combined with technology changes, as has been outlined in the transformative scenarios from [[#10.7|Section 10.7]] and in Chapter 5.

'''Electromobility in land-based transport''' . Since AR5, there has been a significant breakthrough in the opportunities to reduce transport GHG emissions in an economically efficient way due to electrification of land-based vehicle systems, which are now commercially available. EV technologies are particularly well established for light-duty passenger vehicles, including micromobility. Furthermore, there are positive developments to enable EV technologies for buses, light- and medium-duty trucks, and some rail applications (though advanced biofuels and hydrogen may also contribute to the decarbonisation of these vehicles in some contexts). In developing countries, where micromobility and public transit account for a large share of travel, EVs are ideal to support mitigation of emissions. Finally, demand for critical materials needed for batteries has become a focus of attention, as described in Box 10.6.

Electromobility options are moving from regime to landscape levels. This transition is evident in the trend of incumbent automobile manufacturers producing an increasing range of EVs in response to demand, policy, and regulatory signals. EVs for light-duty passenger travel are largely commercial and likely to become competitive with ICE vehicles in the early 2020s ( [[#Dia--2019|Dia 2019]] ; [[#Bond--2020|Bond et al. 2020]] ; [[#Koasidis--2020|Koasidis et al. 2020]] ). As these adopted technologies increase throughout cities and regions, governments and energy suppliers will have to deploy new infrastructure to support them, including reliable low-carbon grids and charging stations ( [[#Sierzchula--2014|Sierzchula et al. 2014]] ). In addition, regulatory reviews will be necessary to ensure equitable transition and achievement of SDGs, addressing the multitude of possible barriers that may be present due to the incumbency of traditional automotive manufacturers and associated supporting elements of the socio-technical system ( [[#Newman--2020b|Newman 2020b]] ) (Chapter 6). Similarly, new partnerships between government, industry, and communities will be needed to support the transition to electromobility. These partnerships could be particularly effective at supporting engagement and education programmes ( [[#Newman--2020b|Newman 2020b]] ) (Chapter 8).

Deployment of electromobility is not limited to developed countries. The transportation sector in low- and middle-income countries includes millions of gas-powered motorcycles within cities across Africa, South-East Asia, and South America ( [[#Posada--2011|Posada et al. 2011]] ; [[#Ehebrecht--2018|Ehebrecht et al. 2018]] ). Many of these motorcycles function as taxis. In Kampala, Uganda, estimates place the number of motorcycle taxis, known locally as ''boda bodas'' , at around 40,000 ( [[#Ehebrecht--2018|Ehebrecht et al. 2018]] ). The popularity of the motorcycle for personal and taxi use is due to many factors including lower upfront costs, lack of regulation, and mobility in highly congested urban contexts ( [[#Posada--2011|Posada et al. 2011]] ; [[#UNECE--2018|UNECE 2018]] ). While motorcycles are often seen as a more fuel-efficient alternative, emissions can be worse from two-wheelers than cars, particularly nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbon emissions ( [[#Vasic--2006|Vasic and Weilenmann 2006]] ; [[#Ehebrecht--2018|Ehebrecht et al. 2018]] ). These two-wheeler emissions contribute to dangerous levels of air pollution across many cities in low- and middle-income countries. In Kampala, for example, air pollution levels frequently exceed levels deemed safe for humans by the World Health Organization (Kampala Capital City Authority 2018; [[#World%20Health%20Organization--2018|World Health Organization 2018]] ; [[#Airqo--2020|Airqo 2020]] ). To mitigate local and environmental impacts, electric ''boda boda'' providers are emerging in many cities, including Zembo in Kampala and Ampersand in Kigali, Rwanda.

Bulawayo, the second-largest city in Zimbabwe, is also looking at opportunities for deploying electromobility solutions. The city is now growing again after a difficult recent history, and there is a new emphasis on achieving the Sustainable Development Goals ( [[#City%20of%20Bulawayo--2020a|City of Bulawayo 2020a]] ; [[#City%20of%20Bulawayo--2020b|City of Bulawayo 2020b]] ). With these goals in mind, Bulawayo is seeking opportunities for investment that can enable leapfrogging in private, fossil fuel vehicle ownership. In particular, trackless trams, paired with solar energy, have emerged as a potential pathway forward ( [[#Kazunga--2019|Kazunga 2019]] ). Trackless trams are a new battery-based mid-tier transit system that could enable urban development around stations and that use solar energy for powering both transit and the surrounding buildings ( [[#Newman--2019|Newman et al. 2019]] ). The new trams are rail-like in their capacities and speed, providing a vastly better mobility system that is decarbonised and enables low transport costs ( [[#Ndlovu--2020|Ndlovu and Newman 2020]] ). While this concept is only under consideration in Bulawayo, climate funding could enable the wider deployment of such projects in developing countries.

'''Fuels for aviation and shipping''' . Despite technology improvements for land-based transport, equivalent technologies for long distance aviation and shipping remain elusive. Alternative fuels for use in long-range aviation and shipping are restricted to the niche level. The aviation sector is increasingly looking towards synthetic fuels using low-carbon combined with CO 2 from direct air capture, while shipping is moving towards ammonia produced using low-carbon hydrogen. Biofuels are also of interest for these segments. To move out of the niche level, there is a need to set deployment targets to support breakthroughs in these fuels. Similarly, there is a need for regulatory changes to remove barriers in new procurement systems that accommodate uncertainty and risks inherent in the early adoption of new technologies and infrastructure ( [[#Borén--2019|Borén 2019]] ; [[#Sclar--2019|Sclar et al. 2019]] ; [[#Marinaro--2020|Marinaro et al. 2020]] ). R&amp;D programmes and demonstration trials are the best focus for achievingfuels for such systems. Finally, there is a need for regulatory changes. Such regulatory changes need to be coordinated through ICAO and IMO as well as with national implementation tools related to the Paris Agreement (see Box 10.5). Long-term visions, including creative exercises for cities and regions, will be required, providing a protected space for the purpose of trialling new technologies ( [[#Borén--2019|Borén 2019]] ; [[#Geels--2019|Geels 2019]] ).

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=== 10.8.2 Feasibility Assessment ===

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Figure 10.23 sets out the feasibility of the core mitigation options using the six criteria created for the cross-sectoral analysis. This feasibility assessment outlines how the conclusions outlined in [[#10.8.1|Section 10.8.1]] fit into the broader criteria created for feasibility in the whole AR6 report and that emphasise the SDGs. Figure 10.23 highlights that there is ''high confidence'' that demand reductions and mode shift can be feasible as the basis of a GHG emissions mitigation strategy for the transport sector. However, demand-side interventions work best when integrated with technology changes. The technologies that can support such changes have a range of potential limitations as well as opportunities. EVs have a reliance on renewable resources (wind, solar, and hydro) for power generation, which could pose constraints on geophysical resources, land use, and water use. Furthermore, expanding the deployment of EVs requires a rapid deployment of new power generation capacity and charging infrastructure. The overall feasibility of electric vehicles for land transport is likely high and their adoption is accelerating. HFCVs for land transport would also have constraints related to geophysical resource needs, land use, and water use. These constraints are likely higher than for EVs, since producing hydrogen with electricity reduces the overall efficiency of meeting travel demand. Furthermore, the infrastructure needed to produce, transport, and deliver hydrogen is under-developed and would require significant R&amp;D and a rapid scale-up. Thus, the feasibility of HFCV is likely lower than for EVs. Biofuels could be used in all segments of the transport sector, but there may be some concerns about their feasibility. Specifically, there are concerns about land use, water use, impacts on water quality and eutrophication, and biodiversity impacts. Advanced biofuels could mitigate some concerns and the feasibility of using these fuels likely varies by world region. The feasibility assessment for alternative fuels for shipping and aviation suggests that hydrogen-based fuels like ammonia and synthetic fuels have the lowest technology readiness of all mitigation options considered in this chapter. Reliance on electrolytic hydrogen for the production of these fuels poses concerns about land and water use. Using ammonia for shipping could pose risks for air quality and toxic discharges to the environment. The DAC/BECCS infrastructure that would be needed to produce synthetic fuel does not yet exist. Thus, the feasibility suggests that the technologies for producing and using these hydrogen-based fuels for transport are in their infancy.

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[[File:b2c83917a66631d831d83b2143fe87c3 IPCC_AR6_WGIII_Figure_10_23.png]]

'''Figure 10.23 | Summary of the extent to which different factors would enable or inhibit the deployment of mitigation options in transport.''' Blue bars indicate the extent to which the indicator enables the implementation of the option (E) and orange bars indicate the extent to which an indicator is a barrier (B) to the deployment of the option, relative to the maximum possible barriers and enablers assessed. An ‘X’ signifies the indicator is not applicable or does not affect the feasibility of the option, while a forward slash indicates that there is no or limited evidence whether the indicator affects the feasibility of the option. The shading indicates the level of confidence, with darker shading signifying higher levels of confidence. Appendix 10.3 provides an overview of the extent to which the feasibility of options may differ across context (e.g., region), time (e.g., 2030 versus 2050), and scale (e.g., small versus large), and includes a line of sight on which the assessment is based. The assessment method is explained in Annex II.11.

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=== 10.8.3 Emerging Transport Issues ===

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'''Planning for integration with the power sector:''' Decarbonising the transport sector will require significant growth in low-carbon electricity to power EVs, and more so for producing energy-intensive fuels, such as hydrogen, ammonia and synthetic fuels. Higher electricity demand will necessitate greater expansion of the power sector and increase land use. The strategic use of energy-intensive fuels, focused on harder-to-decarbonise transport segments, can minimise the increase in electricity demand. Additionally, integrated planning of transport and power infrastructure could enable sectoral synergies and reduce the environmental, social, and economic impacts of decarbonising transport and energy. For example, smart charging of EVs could support more efficient grid operations. Hydrogen production, which is likely crucial for the decarbonisation of shipping and aviation, could also serve as storage for electricity produced during low-demand periods. Integrated planning of transport and power infrastructure would be particularly useful in developing countries where ‘greenfield’ development doesn’t suffer from constraints imposed by legacy systems.

'''Shipping and aviation governance:''' Strategies to deliver fuels in sufficient quantity for aviation and shipping to achieve transformative targets are growing in intensity and often feature the need to review international and national governance. Some authors in the literature have argued that the governance of the international transport systems could be included in the Paris Agreement process ( [[#Gençsü--2015|Gençsü and Hino 2015]] ; [[#Lee--2018|Lee 2018]] ; [[#Traut--2018|Traut et al. 2018]] ). Box 10.6 sets out these issues.

'''Managing critical minerals:''' Critical minerals are required to manufacture lithium-ion batteries (LIB) and other renewable power technologies. There has been growing awareness that critical minerals may face challenges related to resource availability, labour rights, and costs. Box 10.6 sets out the issues, showing how emerging national strategies on critical minerals, along with requirements from major vehicle manufacturers, are addressing the need for rapid development of new mines with a more balanced geography, less use of cobalt through continuing LIB innovations, and a focus on recycling batteries. The standardisation of battery modules and packaging within and across vehicle platforms, as well as increased focus on design for recyclability, are important. Given the high degree of potential recyclability of LIBs, a near closed-loop system in the future would be a feasible opportunity to minimise critical mineral issues.

'''Enabling creative foresight:''' Human culture has always had a creative instinct that enables the future to be better dealt with through imagination ( [[#Montgomery--2017|Montgomery 2017]] ). Science and engineering have often been preceded by artistic expressions; for example Jules Verne first dreamed of the hydrogen future in 1874 in his novel ''The Mysterious Island'' . Autonomous vehicles have regularly occupied the minds of science fiction authors and filmmakers ( [[#Braun--2019|Braun 2019]] ). Such narratives, scenario building, and foresighting are increasingly seen as a part of the climate change mitigation process ( [[#Lennon--2015|Lennon et al. 2015]] ; [[#Muiderman--2020|Muiderman et al. 2020]] ) and can ‘liberate oppressed imaginaries’ ( [[#Luque-Ayala--2018|Luque-Ayala 2018]] ). [[#Barber--2021|Barber (2021)]] emphasised the important role of positive images about the future instead of dystopian visions and the impossibility of business-as-usual futures.

Transport visions can be a part of this cultural change as well as the more frequently presented visions of renewable energy ( [[#Wentland--2016|Wentland 2016]] ; [[#Breyer--2017|Breyer et al. 2017]] ). There are some emerging technologies, like Maglev, Hyperloop, and drones that are likely to continue the electrification of transport even further ( [[#Daim--2021|Daim 2021]] ) and which are only recently at the imagination stage. Decarbonised visions for heavy vehicle systems appear to be a core need from the assessment of technologies in this chapter. Such visioning or foresighting requires deliberative processes and the literature contains a growing list of transport success stories based on such processes ( [[#Weymouth--2015|Weymouth and Hartz-Karp 2015]] ). Ultimately, reducing GHG emissions from the transport sector would benefit from creative visions that integrate a broad set of ideas about technologies, urban and infrastructure planning (including transport, electricity, and telecommunications infrastructure), and human behaviour and at the same time can create opportunities to achieve the SDGs.

'''Enabling transport climate emergency plans, local pledges and net zero strategies:''' National, regional and local governments are now producing transport plans with a climate emergency focus ( [[#Jaeger--2015|Jaeger et al. 2015]] ; [[#Pollard--2019|Pollard 2019]] ). Such plans are often grounded in the goals of the Paris Agreement, based around local low-carbon transport roadmaps that contain targets for and involve commitments or pledges from local stakeholders, such as workplaces, local community groups, and civil society organisations. Pledges often include phasing out fossil fuel-based cars, buses, and trucks ( [[#Plötz--2020|Plötz et al. 2020]] ), strategies to meet the targets through infrastructure, urban regeneration and incentives, and detailed programmes to help citizens adopt change. These institution-led mechanisms could include bike-to-work campaigns, free transport passes, parking charges, or eliminating car benefits. Community-based solutions like solar sharing, community charging, and mobility as a service can generate new opportunities to facilitate low-carbon transport futures. Cities in India and China have established these transport roadmaps, which are also supported by the United Nations Centre for Regional Development’s Environmentally Sustainable Transport programme ( [[#Baeumler--2012|Baeumler et al. 2012]] ; [[#Pathak--2016|Pathak and Shukla 2016]] ; [[#UNCRD--2020|UNCRD 2020]] ). There have been concerns raised that these pledges may be used to delay climate action in some cases ( [[#Lamb--2020|Lamb et al. 2020]] ) but such pledges can be calculated at a personal level and applied through every level of activity from individual, household, neighbourhood, business, city, nation or groups of nations ( [[#Meyer--2020|Meyer and Newman 2020]] ) and are increasingly being demonstrated through shared communities and local activism ( [[#Bloomberg--2017|Bloomberg and Pope 2017]] ; [[#Sharp--2018|Sharp 2018]] ; [[#Figueres--2020|Figueres and Rivett-Carnac 2020]] ). Finally, the world’s major financing institutions are also engaging in decarbonisation efforts by requiring their recipients to commit to Net Zero Strategies before they can receive their funding ( [[#Robins--2018|Robins 2018]] ; [[#Newman--2020a|Newman 2020a]] ) (Chapter 15, Cross-Chapter Box 1 in Chapter 1). As a result, transparent methods are emerging for calculating what these financing requirements mean for transport by companies, cities, regions, and infrastructure projects (Chapters 8 and 15). The continued engagement of financial institutions may, like in other sectors, become a major factor in enabling transformative futures for transport as long as governance and communities continue to express the need for such change.

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=== Box 10.5 | Governance Options for Shipping and Aviation ===

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Whenever borders are crossed, the aviation and shipping sector creates international emissions that are not assigned to states’ Nationally Declared Contributions under the Paris Agreement. Emissions from these segments are rapidly growing (apart from COVID-19 affecting aviation) and are projected to grow between 60% to 220% by 2050 ( [[#IPCC--2018|IPCC 2018]] ; [[#UNEP--2020|UNEP 2020]] ). Currently, the International Civil Aviation Organization (ICAO) and the International Marine Organization (IMO), specialised UN Agencies, are responsible for accounting and suggesting options for managing these emissions.

'''Transformational goals?'''

ICAO has two global aspirational goals for the international aviation sector: 2% annual fuel efficiency improvement through 2050; and carbon neutral growth from 2020 onwards. To achieve these goals, ICAO has established CORSIA – Carbon Offsetting and Reduction Scheme for International Aviation, a market-based programme.

In 2018, IMO adopted an Initial Strategy on the reduction of GHG emissions from ships. This strategy calls for a reduction of the carbon intensity of new ships through implementation of further phases of the energy efficiency design index (EEDI). The IMO calls for a 40% reduction of the carbon intensity of international shipping by 2030, and is striving for a 70% reduction by 2050. Such reductions in carbon intensity would result in an overall decline in emissions of 50% in 2050 (relative to 2008).

These goals are likely insufficiently transformative for the decarbonisation of aviation or shipping, though they are moving towards a start of decarbonisation at a period in history where the options are still not clear, as set out in Sections 10.5 and 10.6.

'''Regulations?'''

The ICAO is not a regulatory agency, but rather produces standards and recommended practices that are adopted in national and international legislation. IMO does publish ‘regulations’ but does not have powers of enforcement. Non-compliance can be regulated by nation states if they so desire, as a ship’s MARPOL certificate, issued by the flag state of the ship, means there is some responsibility for states with global shipping fleets.

'''Paris?'''

Some authors in the literature have argued that emissions from international aviation and shipping should be part of the Paris Agreement ( [[#Gençsü--2015|Gençsü and Hino 2015]] ; [[#Lee--2018|Lee 2018]] ; [[#Traut--2018|Traut et al. 2018]] ; [[#Rayner--2021|Rayner 2021]] ), arguing that the shipping and aviation industries would prefer emissions to be treated under an international regime rather than a national-oriented regime. If international aviation and shipping emissions were a part of the Paris Agreement, it may remove something of the present ambiguity about responsibilities. However, inclusion in the Paris Agreement is unlikely to fundamentally change emissions trends unless targets and enforcement mechanisms are developed, by ICAO and IMO or by nation states through global processes.

'''Individual nations?'''

If international regulations are not made, then the transformation of aviation and shipping will be left to individual nations. In 2020, Switzerland approved a new CO 2 tax on flights ( [[#The%20Swiss%20Parliament--2020|The Swiss Parliament 2020]] ), with part of its revenues earmarked for the development of synthetic aviation fuels, to cover up to 80% of their additional costs compared to fossil jet fuel ( [[#Energieradar--2020|Energieradar 2020]] ). Appropriate financing frameworks will be a key to the large-scale market adoption of these fuels. [[#Egli--2019|Egli et al. (2019)]] suggest that the successful design of investment policies for solar and wind power over the past 20 years could serve as a model for future synthetic aviation fuels production projects ‘attracting a broad spectrum of investors in order to create competition that drives down financing cost’, and with state investment banks building ‘investor confidence in new technologies.’ These national investment policies would provide the key enablers for successful deployments.

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=== Box 10.6 | Critical Minerals and The Future of Electromobility and Renewables ===

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The global transition towards renewable energy technologies and battery systems necessarily involves materials, markets, and supply chains on a hitherto unknown scale and scope. This has raised concerns regarding mineral requirements central to the feasibility of the energy transition. Constituent materials required for the development of these low-carbon technologies are regarded as ‘critical’ materials ( [[#US%20Geological%20Survey--2018|US Geological Survey 2018]] ; [[#Commonwealth%20of%20Australia--2019|Commonwealth of Australia 2019]] ; [[#Lee--2020|Lee et al. 2020]] ; [[#Marinaro--2020|Marinaro et al. 2020]] ; [[#Sovacool--2020|Sovacool et al. 2020]] ). ‘Critical materials’ are critical because of their economic or national security importance, or high risk of supply disruption. Many of these materials and rare earth elements (REEs) as ‘technologically critical’, not only due to their strategic or economic importance but the risk of short supply or price volatility ( [[#Marinaro--2020|Marinaro et al. 2020]] ). In addition to these indicators, production growth and market dynamics are also incorporated into screening tools to assess emerging trends in material commodities that are deemed as fundamental to the well-being of the nation ( [[#NSTC--2018|NSTC 2018]] ).

The critical materials identified by most nations are: REEs neodymium and dysprosium for permanent magnets in wind turbines and electric motors; lithium and cobalt, primarily for batteries though many other metals are involved; and, cadmium, tellurium, selenium, gallium and indium for solar PV manufacture ( [[#Valero--2018|Valero et al. 2018]] ; [[#Giurco--2019|Giurco et al. 2019]] ). Predictions are that the transition to a clean energy world will be significantly energy intensive (World Bank Group 2017; [[#Sovacool--2020|Sovacool et al. 2020]] ), putting pressure on the supply chain for many of the metals and materials required.

Governance of the sustainability of mining and processing of many of these materials, in areas generally known for their variable environmental stewardship, remains inadequate and often a source for conflict. [[#Sovacool--2020|Sovacool et al. (2020)]] propose four holistic recommendations for improvement to make these industries more efficient and resilient: diversification of mining enterprises for local ownership and livelihood benefit; improved traceability of material sources and transparency of mining enterprises; exploration of alternative resources; and the incorporation of minerals into climate and energy planning by connecting to the NDCs under the Paris Agreement.

'''Resource constraints?'''

[[#Valero--2018|Valero et al. (2018)]] highlight that the demand for many of the REEs and other critical minerals will, at the current rate of renewable energy infrastructure growth, increase by 3000 times or more by 2050. Some believe this growth may reach constraints in supply ( [[#Giurco--2019|Giurco et al. 2019]] ). Others suggest that the minerals involved are not likely to physically run out ( [[#Sovacool--2020|Sovacool et al. 2020]] ) if well managed, especially as markets are found in other parts of the world (for example the transition away from lithium from brine lakes to hard rock sources). Lithium hydroxide, more suitable for batteries, now competes well, in terms of cost, when extracted from rock sources ( [[#Azevedo--2018|Azevedo et al. 2018]] ) due to the ability to more easily create high quality lithium hydroxide from rock sources, even though brines provide a cheaper

source of lithium ( [[#Kavanagh--2018|Kavanagh et al. 2018]] ). Australia has proven resources of all the Li-ion battery minerals and has a strategy for their ethical and transparent production ( [[#Commonwealth%20of%20Australia--2019|Commonwealth of Australia 2019]] ). Changes in the technology have also been used to reduce need for certain critical minerals ( [[#Månberger--2018|Månberger and Stenqvist 2018]] ). Recycling of all the minerals is not yet well developed but is likely to be increasingly important ( [[#Habib--2014|Habib and Wenzel 2014]] ; World Bank Group 2017; [[#Giurco--2019|Giurco et al. 2019]] ; [[#Golroudbary--2019|Golroudbary et al. 2019]] ).

'''International collaboration'''

There have been many instances since the 1950s when the supply of essential minerals has been restricted by nations in times of conflict and world tensions, but international trade has continued under the framework of the World Trade Organization. Keeping access open to critical minerals needed for the low-carbon transition will be an essential role of the international community as the need for local manufacture of such renewable and electromobility technologies will be necessary for local economies. [[#Nassar--2020|Nassar et al. (2020)]] report that over the past 30 years the US has become increasingly reliant in imports to meet domestic demand for minerals, including REEs. In terms of heavy REEs, essential for permanent magnets for wind turbines, China has a near-monopoly on REE processing, though other mines and manufacturing facilities are now responding to these constrained markets (Stegen 2015; [[#Gulley--2018|Gulley et al. 2018]] ; [[#Gulley--2019|Gulley et al. 2019]] ; [[#Yan--2020|Yan et al. 2020]] ). China, on the other hand, is reliant on other nations for the supply of other critical metals, particularly cobalt and lithium for batteries.

A number of critical materials strategies have now been developed by nations developing the manufacturing base of new power and transport technologies. Some of these strategies pay particular attention to the supply of lithium ( [[#Martin--2017|Martin et al. 2017]] ; [[#Hache--2019|Hache et al. 2019]] ). For example, Horizon 2020, a substantial EU Research and Innovation programme, couples research and innovation in science, industry, and society to foster a circular economy in Europe, thus reducing bottlenecks in the EU nations. Similarly CREEN (Canada Rare Earth Elements Network) is supporting the US–EU–Japan resource partnership with Australia ( [[#Klossek--2016|Klossek et al. 2016]] ).

As renewables and electromobility-based development leapfrog into the developing world it will be important to ensure the critical minerals issues are managed for local security of supply as well as participation in the mining and processing of such minerals to enable countries to develop their own employment around renewables and electromobility ( [[#Sovacool--2020|Sovacool et al. 2020]] ).

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=== 10.8.4 Tools and Strategies to Enable Decarbonisation of the Transport Sector ===

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Using the right tools and strategies is crucial for the successful deployment of mitigation options. Table 10.7 summarises the tools and strategies required to enable electromobility, new fuels for aviation and shipping, and the more social aspects of demand efficiency.

'''Table 10.7 | Tools and strategies for enabling mitigation options to achieve transformative scenarios.'''

{| class="wikitable"
|-
! '''Tools and strategies'''

! '''Travel demand reduction (TDR) and fu''' '''el/veh''' '''icle efficiency'''

! '''Light vehicle electromobility systems'''

! '''Alternative fuel systems for Shipping and Aviation'''

|-
| Education and R&amp;D

| TDR can be assisted with digitalisation, connected autonomous vehicle, EVs and mobility as a Service ( [[#Marsden--2018|Marsden et al. 2018]] ; [[#Shaheen--2018|Shaheen et al. 2018]] ).

Knowledge gaps on TDR exist for longer distance travel (intercity); non-mandatory trips (leisure; social trips), and travel by older people. Travel demand foresighting tools can be open source ( [[#Marsden--2018|Marsden 2018]] ).

| Behaviour change programmes help EVs become more mainstream. R&amp;D will help on the socio-economic structures that impede adoption of EVs, the urban structures that enable reduced car dependence, and how EVs can assist grids ( [[#Newman--2010|Newman 2010]] ; [[#Taiebat--2019|Taiebat and Xu 2019]] ; [[#Seto--2021|Seto et al. 2021]] ).

| R&amp;D is critical for new fuels and to test the full lifecycle costs of various heavy vehicle options ( [[#Marinaro--2020|Marinaro et al. 2020]] ).

|-
| Access and equity

| TDR programmes in cities can be inequitable. To avoid such inequities, there is a need for better links to spatial and economic development (Marsden et al.2018), mindful of diverse local priorities, personal freedom and personal data (Box 10.1).

| Significant equity issues with EVs in the transition period can be overcome with programmes that enable affordable electric mobility, especially public transit ( [[#IRENA--2016|IRENA 2016]] ).

| Shipping is mostly freight and is less of a problem but aviation has big equity issues ( [[#Bows-Larkin--2015|Bows-Larkin 2015]] ).

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| Financing economic incentives and partnerships

| Carbon budget implications of different demand futures should be published and used to help incentivise net zero projects ( [[#Marsden--2018|Marsden 2018]] ). Business and community pledges for net zero can be set up in partnership agreements ( [[#10.8.3|Section 10.8.3]] ).

| Multiple opportunities for financing, economic incentives, and partnerships with clear economic benefits can be assured, especially using the role of value capture in enabling such benefits. The nexus between EVs and the electricity grid needs opportunities to demonstrate positive partnership projects ( [[#Zhang--2014|Zhang et al. 2014]] ; [[#Mahmud--2018|Mahmud et al. 2018]] ; [[#Newman--2018|Newman et al. 2018]] ; [[#Sovacool--2018|Sovacool et al. 2018]] ; [[#Sharma--2020|Sharma and Newman 2020]] ).

| Taking R&amp;D into demonstration projects is the main stage for heavy vehicle options and these are best done as partnerships. Government assistance will greatly assist in such projects as well as an R&amp;D levy. Abolishing fossil fuel subsidies and imposing carbon taxes is likely to help in the early stages of heavy vehicle transitions ( [[#Sclar--2019|Sclar et al. 2019]] ).

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| Co-benefits and overcoming fragmentation

| Programmes that focus on people-centred solutions for future mobility, with more pluralistic and feasible sets of outcomes for all people, can be successful. They need to focus on more than simple benefit-cost ratios and include well-being and livelihoods, considering transport as a system rather than loosely connected modes, as well as behaviour change programmes ( [[#Barter--2000|Barter and Raad 2000]] ; [[#Newman--2010|Newman 2010]] ; [[#Martens--2020|Martens 2020]] ).

| The SDG benefits of zero-carbon light vehicle transport systems are being demonstrated and can now be quantified as nations mainstream this transition. Projects with transit and sustainable housing are more able to show such benefits. New benefit-cost ratio methods that focus on health benefits in productivity are now favouring transit and active transport ( [[#Buonocore--2019|Buonocore et al. 2019]] ; [[#UK%20DoT--2019|UK DoT 2019]] ; [[#Hamilton--2021|Hamilton et al. 2021]] ).

| Heavy vehicle systems can also demonstrate SDG co-benefits if formulated with these in mind. Demonstrations of how innovations can also help SDGs will attract more funding. Such projects need cross-government consideration ( [[#Pradhan--2017|Pradhan et al. 2017]] ).

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| Regulation and assessment

| Implementing a flexible regulatory framework is needed for most TDR ( [[#Li--2018|Li and Pye 2018]] ). Regulatory assessment can help with potential additional (cyber) security risks due to digitalisation, autonomous vehicles, the internet of things, and big data ( [[#Shaheen--2019|Shaheen and Cohen 2019]] ). Assessment tools and methods need to take account of greater diversity of population, regions, blurring of modes, and distinct spatial characteristics ( [[#Newman--2015|Newman and Kenworthy 2015]] ).

| With zero-carbon light vehicle systems rapidly growing, the need for a regulated target and assessment of regulatory barriers can assist each city and region to transition more effectively. Regulating EVs for government fleets and recharge infrastructure can establish incentives ( [[#Bocken--2016|Bocken et al. 2016]] ).

| Zero-carbon heavy vehicle systems need to have regulatory barrier assessments as they are being evaluated in R&amp;D demonstrations ( [[#Sclar--2019|Sclar et al. 2019]] ).

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| Governance and institutional capacity

| TDR works better if adaptive decision-making approaches focus on more inclusive and whole-of-system benefit-cost ratios ( [[#Marsden--2018|Marsden 2018]] ; [[#Yang--2020|Yang et al. 2020]] ).

| Governance and institutional capacity can now provide international exchanges and education programmes based on successful cities and nations, enabling light vehicle decarbonisation to create more efficient and effective policy mechanisms towards self-sustaining markets ( [[#Greene--2014|Greene et al. 2014]] ; Skjølsvold and Ryghaug 2019).

| Governance and institutional capacity can help make significant progress if targets are backed with levies for not complying. Carbon taxes would also affect these segments. A review of international transport governance is likely ( [[#Makan--2018|Makan and Heyns 2018]] ).

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| Enabling infrastructure

| Ensuring space for active transport and urban activities is taken from road space will be necessary in some places ( [[#Gössling--2021b|Gössling et al. 2021b]] ).

Increasing the proportion of infrastructure that supports walking in urban areas will structurally enable reductions in car use ( [[#Newman--2015|Newman and Kenworthy 2015]] ) ( [[#10.2|Section 10.2]] ).

Creating transit activated corridors of transit-oriented development-based rail or mid-tier transit using value capture for financing will create inherently less car dependence ( [[#McIntosh--2017|McIntosh et al. 2017]] ; [[#Newman--2019|Newman et al. 2019]] ).

| Large-scale electrification of LDVs requires expansion of low-carbon power systems, while charging or battery swapping infrastructure is needed for some segments ( [[#Gnann--2018|Gnann et al. 2018]] ; [[#Ahmad--2020|Ahmad et al. 2020]] ).

| In addition to increasing the capabilities to produce low- or zero-carbon fuels for shipping and aviation, there is a need to invest in supporting infrastructure including low-carbon power generation. New hydrogen delivery and refuelling infrastructure may be needed ( [[#Maggio--2019|Maggio et al. 2019]] ). For zero-carbon synthetic fuels, infrastructure is needed to support carbon capture and CO 2 transport to fuel production facilities ( [[#Edwards--2018|Edwards and Celia 2018]] ).

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