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The impact of rapidly falling costs of renewable energy and battery technology on long-term climate stabilization pathways is not well understood. Luderer et al. show that reduced renewable costs and climate policies will make electricity the cheapest energy carrier and can lead to electricity accounting for nearly two-thirds of global energy use by mid-century.

This analysis of net-zero strategies designed in an iterative stakeholder dialogue finds that without behavioral change and with restriction of technologies, the target of greenhouse gas neutrality in the European Union cannot be reached.

This scenario study investigates how the EU net-zero target can be reached with varying levels of residual fossil fuels. Reducing fossils by only 90% relies on substantial carbon storage, while a full fossil phase-out requires a rapid scale-up of expensive carbon-neutral e-fuels.

To evaluate the effectiveness of current national policies in achieving global temperature targets is important but a systematic multi-model evaluation is still lacking. Here the authors identified a reduction of 3.5 GtCO₂ eq of current national policies relative to a baseline scenario without climate policies by 2030 due to the increasing low carbon share of final energy and the improving final energy intensity.

This study analyses the consequences on mitigation pathways and economic efficiency of a separation for CO₂ and removal targets to achieve global net-zero CO2 emissions and finds that the economic efficiency losses of such separation are limited.

All energy generation technologies emit greenhouse gases during their life cycle as a result of construction and operation. Pehl et al. integrate life-cycle assessment and energy modelling to analyse the emissions contributions of different technologies across their lifespan in future low-carbon power systems.

Abatement options for hard-to-electrify sectors (e.g., steel, aviation) face uncertainty in future costs and feasibility. This techno-economic analysis shows that despite these uncertainties, a single most promising solution can be identified for each sector.

The societal response to the pandemic has reduced global power demand, disproportionally affecting coal power generation and thus leading to a strong CO₂ emissions decline. Policy should apply 2020’s lessons to ensure that power sector emissions have peaked in 2018 and go into structural decline.

Achieving the Paris Agreement’s climate goals depends on safeguarding and monitoring the permanence of forest carbon stocks, as delays in addressing their vulnerability to disturbances drastically increase mitigation costs and efforts.

A model shows how climate targets could be met by 2030 through a politically feasible mix of carbon pricing, low-carbon technology, and energy policy.

Residual CO₂ emissions from fossil fuels limit the likelihood of meeting the goals of the Paris Agreement. A sector-level assessment of residual emissions using an ensemble of IAMs indicates that 640–950 GtCO₂ removal will be required to constrain warming to 1.5 °C.

There lacks a consistent and holistic evaluation of co-benefits of different mitigation pathways in studies on Integrated Assessment Models. Here the authors quantify environmental co-benefits and adverse side-effects of a portfolio of alternative power sector decarbonisation pathways and show that the scale of co-benefits as well as profiles of adverse side-effects depend strongly on technology choice.

Energy models play a crucial role in studying mitigation strategies; however, substantial variations among these models exist. This study presents a typology for energy models to map these model differences, based on five dimensions, each characterized by numerous diagnostic indicators.

Large emission reductions in buildings and transport are possible by integrating demand-side strategies to electrify energy use, improve technological efficiency, and reduce or shift patterns of activity. With enabling policies and infrastructures, final energy users can make significant contributions to climate goals, particularly through widespread deployment of heat pumps and electric vehicles.

The Paris Agreement requires reaching net-zero carbon emissions, but a debate exists on how fast this can be achieved. This study establishes scenarios with different feasibility constraints and finds that the institutional dimension plays a key role for determining the feasible peak temperature.

This analysis shows that demand-side policies can reduce emissions by 51–85% in buildings and 37–91% in transport by 2050, with electrification having the greatest impact. Adopting a mix of strategies offers benefits for the overall energy system.

EU emissions trading system carbon prices have surged since 2017. Here the authors consider sources of this increase and note that increased foresight driven by stronger commitment to climate targets has played a role. Prices also run the risk of dropping if policy credibility is undermined.

Recent reforms of the EU Emissions Trading System (EU ETS) boosted carbon prices by tightening the cap on emission allowances and increasing political commitment to it, which effectively made actors more farsighted. Policymakers should thus view prices as an indicator of credibility as well as scarcity, and manage potential future drops in the former by renewing commitment to the cap.

Bioenergy has been widely viewed as an alternative for fossil fuels and an option for carbon dioxide removal, but there are doubts given the induced land-use changes. This study shows the importance of uniform regulation and comprehensive coverage of carbon-rich areas in reducing total emissions.

Under current land-use regulation, carbon dioxide emissions from biofuel production exceed those from fossil diesel combustion. Therefore, international agreements need to ensure the effective and globally comprehensive protection of natural land before modern bioenergy can effectively contribute to achieving carbon neutrality.

Current emissions scenarios include pathways that overshoot the temperature goals set out in the Paris Agreement and rely on future net negative emissions. Limiting overshoot would require near-term investment but would result in longer-term economic benefit.

Current action is insufficient to meet both the Paris Agreement and the Sustainable Development Goals. Integrated model-based analysis shows that strong interventions across many dimensions, together with ambitious lifestyle change, are needed to enable real progress towards the UN Agenda 2030.

Many trajectories for reaching climate change mitigation targets exaggerate the long-term need for CO₂ removal (CDR) because they assume an exponentially increasing carbon price. Here the authors analyse alternative carbon price pathways that halt warming while limiting CDR, and may be easier to implement.

Despite global initiatives to reach net-zero CO2 emissions, the tradeoffs of energy systems to reach that goal remain understudied. Here the authors analyze all net-zero scenarios used for the 2018 IPCC report and quantify the role of renewable energy, fuels, and emissions in attaining a zero CO2 world.

An integrated assessment model analysis shows that a moderately differentiated carbon price could achieve as much climate mitigation as a uniform carbon tax, avoiding concerns regarding equity between participating countries or sovereignty.

Scenarios that constrain end-of-century radiative forcing to 1.9 W m^–2, and thus global mean temperature increases to below 1.5 °C, are explored. Effective scenarios reduce energy use, deploy CO₂ removal measures, and shift to non-emitting energy sources.

Green hydrogen is a crucial part of plans to achieve climate targets, yet how quickly supply will scale is unclear. Using a technology diffusion model, Odenweller et al. suggest that even if electrolysis capacity grows as quickly as wind and solar power, green hydrogen supply will suffer from short-term scarcity and long-term uncertainty.

Coal use is responsible for a large proportion of climate damages. This study shows that phasing out coal yields substantial near-term, local environmental and health benefits that outweigh direct policy costs, providing incentives for immediate climate action.

A new analysis shows that global warming could be limited to 1.5 °C by 2100, but that the window for achieving this is small and rapidly closing.

Despite being currently under-represented in IPCC reports, PV generation represents a growing share of power generation. This Perspective argues that underestimating PV potential led to suboptimal integration measures and that specific deployment strategies for emerging economies should be developed.

E-fuels—hydrocarbon fuels synthesized from green hydrogen—can replace fossil fuels. This Perspective highlights the opportunities and risks of e-fuels, and concludes that hydrogen and e-fuels should be prioritized for sectors inaccessible to direct electrification.

Experts using integrated assessment models to analyse the effects of climate change policy, have recently engaged in model inter-comparison projects (MIPs) to generate conclusions robust to different models' specifications. This Review synthesises results from the most comprehensive MIP that focuses on the different possible outcomes of post-2020 climate negotiations, recently announced pledges and their relation to the 2°C target.