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In recent years, the utilization of biomass through advanced power technologies has intensified to achieve carbon neutrality. An oxy-fuel circulating fluidized bed combustor of biomass with higher efficiency supercritical carbon dioxide cycle has been developed with the aim of compensating the penalties for carbon capture and storage. The combustor fuelled with waste paper, waste wood, and cow manure, at an input of 200 ton/day is economically evaluated. Waste paper is on the verge of becoming an economically feasible fuel, more so than the other biomass examined. The use of waste paper led to a positive net present value, an internal rate of return of 3.8%, a benefit-cost ratio of 1.025, and a payback period of 17.7 years. Subsequent sensitivity analyses conducted for the waste paper fuelled power plant indicated that the capital cost is the most influential factor; the boiler, supercritical carbon dioxide cycle, and oxygen fuel combustion system were indicated in descending order of related subdivided sensitiveness. Both renewable energy certificate and carbon credit has contributed to the feasible economic of the system, with former one took precedence over later one. Sensitivity from the technical perspective, improvement in air separation unit is likely to greatly improve the economic feasibility of the proposed system. The power consumption of the air separation unit, as well as that of the carbon dioxide compression and purification unit, were highly sensitive to the implementation cost. [Display omitted] • Integration of oxygen combustion and supercritical carbon dioxide power cycle. • Economic feasibility study of integrated biomass circulating fluidized bed. • Capital cost demonstrated the foremost sensitivity factor. • Waste paper as potential economically feasible fuel. • Innovation in air separation unit improves economic feasibility. [ABSTRACT FROM AUTHOR]

CO 2 sequestration has proven to be an attractive way to combat global warming. However, due to the corrosive nature of CO 2 , chemical reactions between CO 2 and the host rock can happen after the injection. This study reviews the current state of knowledge about chemical reactions and their effects on the mineralogy, structure, mechanical, deformation, and transport properties of different types of rocks from research papers published in 2004–2024. In addition to drawing a comprehensive picture of the research that has been done on the subject and the gaps that need to be filled, this review combined the data from the papers to introduce the relationships between exposure conditions (CO 2 pressure, exposure duration, and temperature) and mineralogy, strength, and elastic properties, and permeability of multiple types of rocks. Results showed that some minerals like quartz are not affected by CO 2 while others like carbonates can easily be dissolved. Datapoints from various papers showed a negative effect of CO 2 pressure and exposure duration, and a positive effect of temperature on the strength properties of rocks. An increase in permeability was another consequence of CO 2 treatment in most cases. This study is one of the first works to gather data from multiple sources in developing relationships between CO 2 treatment conditions and the strength properties of rocks. Results will potentially improve understanding and prediction of the effect of CO 2 on the properties and behavior of rocks. [Display omitted] • Quartz, unlike carbonates, is not impacted by CO 2. • Dissolution/precipitation of minerals leads to increase/decrease in pore volume. • The compressive strength mostly decreases with an increase in CO 2 pressure. • Bulk and elastic moduli of rocks decrease after CO 2 treatment. • CO 2 increases the permeability of most rocks. [ABSTRACT FROM AUTHOR]

Negative emission technologies driven by nature with less energy input, lower costs, and long carbon storage capacities are essential for meeting ambitious global carbon mitigation goals. This paper evaluates the carbon sequestration potential of bivalve shellfish farming because its sequestration process is driven by nature, and it is cost-effective and energy efficient. The carbon in shells and the carbon that enters sediments via bio-deposition are long-lived forms of carbon. Using China as a case study, a preliminary estimation suggests that the carbon sequestration efficiency and intensity of cultivated shellfishes are much higher than those of artificial forests. In China, approximately 6.23 Mt CO 2 -eq a−1 was fixed via net carbon sequestration during shellfish growth from 2015 to 2019. In addition, the farmed shellfishes provided 0.37 Mt of harvested protein, and approximately 37.39 Mt CO2-eq a-1 were reduced compared to the same amount of protein provided by beef, and thus, shellfish farming has the win-win benefits of carbon sequestration and high-quality food provision. More importantly, a total of 5.64 Gt CO 2 -eq, accounting for 17.63% of the total emissions in 2020, can be potentially sequestrated at the global scale under the world's largest farming area scenario. • A Negative Emission Technology via shellfish farming was introduced. • Carbon sequestration function and efficiency of shellfish farming were investigated. • Carbon sequestration potential for bivalve shellfish farming was evaluated globally. • Life cycle GHG emissions of shellfish farming in China was assessed. [ABSTRACT FROM AUTHOR]

Low-carbon and environmentally friendly development are becoming increasingly important in the metallurgical industry. In this study, the use of biomass as a source of both material and energy in metallurgical technologies is reviewed. The paper discusses the preparation of bio-based raw materials, their utilization in metallurgical processes, phytoremediation and metal extraction technology, and forestry as a carbon dioxide sequestration method. Bio-based raw materials, such as bio-based fuels, reductants, adhesives, and activated carbons, are found to provide energy, act as reductants and binders, dispose metallurgical flue gas, and adjust metal melt composition, thereby reducing energy consumption in metallurgical processes. Additionally, heavy metals can be enriched in plants through biomass-mediated soil remediation, and these metals can then be processed to obtain raw materials for metallurgical processes. Moreover, metallurgical waste heat can be used to prepare biomass as soil amendments, remediate deserts, and indirectly reduce metallurgical industry carbon dioxide emissions through forest carbon sinks. Based on these findings, the concept of biomass metallurgy is proposed, which promotes the use of biomass as energy or raw materials, ecological restoration and reforestation, and reduction of carbon dioxide and pollutant emissions in metallurgical processes. This study emphasizes the advantages of biomass metallurgy and encourages the development of low-carbon and green metallurgical processes. [Display omitted] • Development of metallurgical technologies using bio-based material and energy. • Bio-based materials including fuels, reductants, adhesives, and activated carbon. • Biomass used in metallurgy for combustion, reductants, pellets making, etc. • Heavy metals in hyperaccumulators extracted and recovered by biochemical methods. • Indirectly reducing CO 2 by transforming metallurgical waste heat into carbon sinks. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) is a crucial strategy for achieving CO 2 emission reduction targets and mitigating the impacts of global warming and climate change. Among various CCUS technologies, chemical absorption of CO 2 has proven to be a mature and widely-used technique in various industrial sectors. However, the current CO 2 chemical absorption process involves large-scale equipment with low efficiencies, making it difficult to control. To address these issues, microfluidic devices have emerged as a promising technology to intensify the CO 2 absorption process by providing a smaller required volume, enhanced mass transfer, cleaner and safer operations, higher productivity, and more efficient energy use. This paper aims at presenting a comprehensive literature review on research advances of the microfluidic technology for CO 2 chemical absorption. The review covers various aspects, including microchannel geometries, two-phase flow patterns, mass transfer models, effects of operating factors, and measures to intensify the CO 2 absorption process. In addition, the paper discusses the measurement of interfacial and local parameters, such as liquid film thickness, velocity field, and local CO 2 concentration, which are primordial for understanding the transport phenomena and for optimizing the CO 2 absorbers. This paper may serve as an essential reference that contributes to the development and exploitation of highly-efficient microfluidic-based CO 2 chemical absorption technology for future large-scale industrial applications. [Display omitted] • Recent researches on microfluidic-based CO 2 chemical absorption are reviewed. • Absorption performance is determined by the mass transfer between CO 2 and absorbent. • Effects of influencing operational factors are discussed. • Optical techniques are frequently used to measure local & interfacial parameters. • Different techniques used to intensify the CO 2 absorption process are surveyed. [ABSTRACT FROM AUTHOR]

Natural gas hydrate (NGH) is a source of energy that has attracted significant interest for the secure and effective extraction of CH 4 gas from permafrost and marine regions. CH 4 gas can be produced and greenhouse gases (GHG) sequestrated by injecting flue gas into NGH, minimizing environmental threats. This paper provides a complete summary of the advancement of CH 4 recovery from NGH by CO 2 replacement. The CH 4 –CO 2 exchange mechanisms are examined in different types of hydrates concerning their cage structure and formation in geological layers. The gas composition of CO 2 injected with H 2 , N 2 , and air, thermodynamic pressure and temperature, hydrate and water saturations, and concentration of CO 2 are factors influencing the efficiency of the CH 4 –CO 2 exchange. The structural integrity of the sedimentary film throughout the exchange process is evaluated, and the evaluation indicates that the hydrate formed by CO 2 gas is stronger than the layer formed by CH 4 gas and that the mechanical integrity of the reservoirs can be maintained after the exchange process. The replacement effect of CH 4 –CO 2 combined with depressurization, thermal stimulation, and other factors is discussed. Restrictions and further studies of the CH 4 –CO 2 exchange process are also analyzed in light of current findings. This article offers information for future NGH extraction and CO 2 storage applications by providing an overview of recent advances in CH 4 –CO 2 replacement. • Mechanism of CH 4 –CO 2 replacement comprises CH 4 extraction and CO 2 sequestration. • Using different compositions of N 2 and H 2 gases with CO 2 enhances CH 4 –CO 2 exchange. • Combination of thermal stimulation with CO 2 exchange improves CH 4 recovery rate. • Mechanical properties of CH 4 –CO 2 hydrates maintain the mechanical integrity of rock. [ABSTRACT FROM AUTHOR]

This paper provides a review of negative carbon capture technologies. Based on these technologies, here it is proposed an innovative negative emissions power plant combining the generation and storage of energy from biomass, photovoltaic, and concentrated solar power, capturing and recovering CO 2 by producing H 2 or CH 4 as green energy carriers. The main features of the system are i) large-scale energy production system with negative CO 2 emissions; ii) 100% renewable system based on biomass and solar energy with the possibility of integrating other renewables; iii) synergistic integration of processes and systems; iv) recovery of O 2 generated by photovoltaic-driven electrolysis within the process of partial biomass oxycombustion and v) solar-driven limestone calcination. A detailed model of the entire plant is developed to evaluate the integration of the process. The model performance is assessed on an hourly basis throughout the whole year. The base case results show an energy consumption from 1 to 2.1 MJ/kg CO 2 to capture 60–77% of CO 2 emitted from the biomass plant and green methane production of more than 7500 tons/year. The negative emissions associated with the process are -612 kg CO 2 /MWh. It justifies the interest in the proposed negative emissions power plant. [Display omitted] • A synergetic integration of CO2 capture, energy storage and methane production is proposed. • A biomass power plant is considered, resulting in -612 kg CO2/MWh negative emissions. • Solar PV and CSP are integrated into the process to reduce the SPECCA to 1–2.1 kg CO2/MWh. • A large amount of solids storage is required to achieve 70–90% CO2 capture capacity. [ABSTRACT FROM AUTHOR]

Biochar amendment has been proposed as a promising solution to mitigate greenhouse gas (GHG) emissions from agriculture and sustainably enhance crop yield. However, the net GHG mitigation potential of biochar remains uncertain, especially the controversial results from field and laboratory experiments. Using 9970 published observational data derived from 592 peer-reviewed papers, this study highlighted the effects of biochar in field experiments on crop yield, soil organic carbon (SOC) stocks, carbon dioxide (CO 2) and methane (CH 4) fluxes, and soil nitrogen (N) dynamics (i.e., soil inorganic N stocks, nitrous oxide [N 2 O] emissions, ammonia [NH 3 ] volatilization, and inorganic N leaching). Overall, field data indicated that biochar significantly increased gross SOC stocks (26.6%) and crop yield (15.7%), reduced soil CH 4 (−14.8%) and N 2 O (−23.1%) emissions, and ammonium (−24.9%) and total inorganic N leaching (−23.2%) but had no effect on soil CO 2 emissions. Whereas laboratory data generally showed greater effect sizes of biochar on these indictors. Global warming potential was decreased only in field experiments, but both experiments showed similar reductions in GHG intensity. Both experiments suggested that soil and biochar cation exchange capacity, pH, biochar application rate, and nitrogen fertilization interactively regulated biochar effects on crop yield and GHG emissions. The unrealistically high rates of biochar in laboratory experiments may overestimate its benefit on soil C sequestration and/or underestimate its mitigation potential. These findings provide a comprehensive view that biochar amendment may serve as a viable climate-smart agricultural practice that can help in partial achievement of multiple sustainable development goals. • Biochar is an effective strategy for climate-smart agriculture. • Biochar added to field (∼20 Mg ha−1) can increase gross SOC stock by ∼27%. • Biochar can decrease global warming potential and greenhouse gas intensity. • Unrealistically high biochar rates in lab overestimated soil carbon sequestration. [ABSTRACT FROM AUTHOR]

The carbonation technology, which is promising in carbon capture and storage, is an emerging soil treatment method adopted in geotechnical engineering and geo-environmental engineering to enhance mechanical properties or mitigate environmental risks. The advantage of utilising CO 2 in solving engineering problems shows a large potential for the technology to be widely used to alleviate the greenhouse emission problems; Nevertheless, the changes in soil characteristics, including physical, chemical, mechanical, deformation, and durability characteristics, caused by carbonation are complicated, which brings challenges to possible engineering applications. This paper reviews the recent development of carbonation technology in geotechnical engineering and provides a systematic analysis of the effect of carbonation on soil properties, from the macro behaviours to the micro mechanism. The "double-edged sword" effect of carbonation on the mechanical properties of soils is proposed, together with the micro-scale mechanisms illustrated. A qualitative theoretical model for the prediction of the mechanical strength of carbonated soils is established. The prospective future and important insights of the carbonation technology to be utilized in geotechnical engineering can be concluded from the review, although some potential technical issues, including possible carbonation crack, heavy metal leaching, durability issues, and lack of construction techniques, require further study. [Display omitted] • Natural and artificial carbonation process in soils. • Carbonation technology for ground improvement and contaminated soil treatment. • Physical, chemical, and mechanical characteristics of carbonated soils. • Microscopic structures and chemical reactions of the carbonation process. • Positive and negative influences of carbonation on soil properties. [ABSTRACT FROM AUTHOR]

As a mature technology in carbon capture process, amine scrubbing technology has many advantages such as fast absorption rate, high carbon dioxide (CO 2) selectivity, high CO 2 absorption, excellent absorption effect and regeneration, but it also has many problems such as high energy consumption for regeneration, corrosion of carbon steel, easy degradation, carcinogenic and some environmental risks that limit its commercial use. Therefore, it is important to screen the amines in the absorption process of different gas mixtures by amine washing technology in specific environments. In this paper, we systematically review the current development of amine scrubbing technology for carbon capture in terms of amine structure, reaction mechanism, operation procedure, problems and its application status. The structures and reaction mechanisms of different types of amines are explained and classified in detail to provide guidance for the subsequent screening of monoamine and mixed amines technologies. In addition, the possible problems in the process of gas absorption and its application scenarios are explained and the corresponding research ideas and suggestions are presented. Finally, we also propose specific directions for future research on amine scrubbing technology to provide guidance for the continued promotion of processes that can effectively perform carbon capture. [Display omitted] • Amine has great advantages in CO 2 capture effect and treatment capacity. • The regeneration energy and degradation of amine need to be further studied. • The potential environmental risk of amine degradation needs more attention. • Lack of systematization of the optimal process parameters of mixed amines. [ABSTRACT FROM AUTHOR]

Small Island Developing States (SIDS) have a high dependency on fossil fuels for energy, water, and food production. This has negative implications on the carbon footprint and resilience of the SIDS. Wind power is one of the most promising options for renewable energy in the coastal areas of the SIDS. To account for the seasonal intermittent nature of wind energy, ammonia can be used for energy storage. In this paper, ammonia as an energy vector, is examined to reduce the costs and carbon footprint of energy on the island of Curaçao as a showcase for Caribbean SIDS. The levelized cost of electricity (LCOE) for the combined wind and ammonia energy storage system is 0.13 USD/kWh at a discount rate of 5%. This is cost competitive with the LCOE of 0.15–0.17 USD/kWh from heavy fuel oil, which is the main electricity source in the Caribbean SIDS. In Curaçao, the LCOE from LNG and coal without carbon capture and storage (CCS) is 0.07–0.10 USD/kWh and 0.09–0.14 USD/kWh, respectively. When CCS is applied, the LCOE from LNG and coal is 0.10–0.13 USD/kWh and 0.14–0.21 USD/kWh, respectively. This suggests that the LCOE of the combined wind and ammonia energy storage system can be competitive with fossil-based alternatives with carbon capture and storage (CCS) in a decarbonized energy landscape. The CO 2 -footprint of the combined wind energy and ammonia energy storage system is 0.03 kg CO 2 /kWh, compared to 0.04 kg CO 2 /kWh and 0.12 kg CO 2 /kWh for LNG-/coal-based energy generation with CCS, respectively. [Display omitted] • Green ammonia seasonal energy storage is feasible in Curaçao (Caribbean SIDS). • Absorption Enhanced Haber-Bosch using Ru-catalysts results in a LCOE of 0.13 USD/kWh. • Wind energy combined with ammonia energy storage leads to a carbon footprint of just 0.03 kg CO 2 /kWh. • Hybrid thermal and membrane processes enable zero-liquid discharge seawater desalination. [ABSTRACT FROM AUTHOR]

The current editorial summarized some of the scientific works presented in the Sustainable Energy and Environmental Protection (SEEP) conference-held at the University of the West of Scotland, UK, 2018. The selected work was directly related to the scope of the Renewable, Sustainable Energy Reviews (RSER) journal. During the conference activities, experts from all around the world in the subjects of: renewable energy, climate change, optimization, and economics presented and discussed the progress made in renewable energy sources, as well as the new strategies for protecting the environment from the hazards connected with fossil fuel utilization. The methods presented in the conference focused on several directions: the development of efficient energy conversion systems with low/no environmental impacts; the suggested policies to widespread renewable energies; the restriction in the emission of greenhouse gases, and the recent progresses in CO 2 capture. This editorial focused on the renewable energy developments and their positive effect on the climate change, and briefly summarized the accepted manuscripts in this issue. • Effects of renewable energy on climate change. • Background on the International Conference on Sustainable Energy and Environmental Protection SEEP. • Summary of selected papers of SEEP 2018. [ABSTRACT FROM AUTHOR]

The implementation of negative emission technologies (NETs) is vital to limit global warming to manageable levels. Despite the lack of technological maturity of NETs, their full-scale implementations are expected to take place within the next few decades. Potential interactions with energy infrastructures need to be considered during scale-up. This paper develops a graphical targeting technique for the implementation of energy-consuming NETs (EC-NETs) for sustainable energy planning. The graphical targeting technique is illustrated using a case study, which demonstrates the usefulness of EC-NETs for an effective carbon management strategy. However, the energy demand of EC-NETs requires compensation from additional renewable energy sources. The deployment of CO 2 Capture and Storage (CCS) decreases the requirement of renewable energy sources by 88%. On the other hand, the implementation of EC-NETs coupled with energy-producing NETs (EP-NETs) eliminates the need for renewable energy sources to compensate for the incremental demand, as EP-NETs supplies the energy requirements of EC-NETs. CCS deployment reduces the use of EP-NETs by 82%. The case studies illustrate how a systematic methodology for integrated energy planning can optimise decarbonisation while minimising the impacts on energy infrastructure. [Display omitted] • Concurrent solutions are needed for future decarbonisation. • EC-NETs provide a good alternative for cases with limited availability of EP-NETs. • The graphical targeting method provides good insights for CO 2 emission removal. • EC-NETs utilisation increases the minimum implementation of make-up energy. [ABSTRACT FROM AUTHOR]

The current editorial summarized some of the scientific works presented in the Sustainable Energy and Environmental Protection (SEEP) conference-held at the University of the West of Scotland, UK, 2018. The selected work was directly related to the scope of the Renewable, Sustainable Energy Reviews (RSER) journal. During the conference activities, experts from all around the world in the subjects of: renewable energy, climate change, optimization, and economics presented and discussed the progress made in renewable energy sources, as well as the new strategies for protecting the environment from the hazards connected with fossil fuel utilization. The methods presented in the conference focused on several directions: the development of efficient energy conversion systems with low/no environmental impacts; the suggested policies to widespread renewable energies; the restriction in the emission of greenhouse gases, and the recent progresses in CO 2 capture. This editorial focused on the renewable energy developments and their positive effect on the climate change, and briefly summarized the accepted manuscripts in this issue. • Effects of renewable energy on climate change. • Background on the International Conference on Sustainable Energy and Environmental Protection SEEP. • Summary of selected papers of SEEP 2018. [ABSTRACT FROM AUTHOR]

The implementation of negative emission technologies (NETs) is vital to limit global warming to manageable levels. Despite the lack of technological maturity of NETs, their full-scale implementations are expected to take place within the next few decades. Potential interactions with energy infrastructures need to be considered during scale-up. This paper develops a graphical targeting technique for the implementation of energy-consuming NETs (EC-NETs) for sustainable energy planning. The graphical targeting technique is illustrated using a case study, which demonstrates the usefulness of EC-NETs for an effective carbon management strategy. However, the energy demand of EC-NETs requires compensation from additional renewable energy sources. The deployment of CO 2 Capture and Storage (CCS) decreases the requirement of renewable energy sources by 88%. On the other hand, the implementation of EC-NETs coupled with energy-producing NETs (EP-NETs) eliminates the need for renewable energy sources to compensate for the incremental demand, as EP-NETs supplies the energy requirements of EC-NETs. CCS deployment reduces the use of EP-NETs by 82%. The case studies illustrate how a systematic methodology for integrated energy planning can optimise decarbonisation while minimising the impacts on energy infrastructure. [Display omitted] • Concurrent solutions are needed for future decarbonisation. • EC-NETs provide a good alternative for cases with limited availability of EP-NETs. • The graphical targeting method provides good insights for CO 2 emission removal. • EC-NETs utilisation increases the minimum implementation of make-up energy. [ABSTRACT FROM AUTHOR]

Carbon Capture Utilization and Storage (CCUS) technology is an essential component to decarbonize society and reach carbon neutrality. Its success depends on not only technological advances but also people's reaction to it. This study applied traditional content analysis to uncover the CCUS reporting landscape and employed the Socio-Political Evaluation of Energy Deployment (SPEED) framework to explore how different aspects of the CCUS value chain were discussed in Chinese newspapers. A total of 492 news items from November 21st 2002 to May 8th 2021 were identified and analyzed. Results showed that news coverage of CCUS technology in China started in 2005. The media explained the nature and sources of carbon dioxide (CO 2), framed CCUS by various terms, for example, " greengen " and " a clean energy technology ", as well as demonstrated various tones in CCUS. The analysis found 71.3% (N = 351) of newsletters took an affirmative stance towards CCUS. It was also revealed that environmental frames appeared in almost every article, while much less attention was paid to other issues. Moreover, this research demonstrated that CCUS-related policies were driving media coverage closely year by year. However, current news presentations were inadequate due to technical misperceptions and a lack of comprehensive coverage. Therefore, this research proposed a science-for-the-community communication strategy that involved several key factors such as policy guidance, newspaper functions at different levels, journalist training, direct engagement of the public as well as student education. • This paper pioneered to investigate Chinese newspaper coverage of CCUS technology. • The frequency of CCUS inclusion in newspapers was somehow affected by policies in China. • CCUS reporting revolved its emission reduction potential, and CCUS influences on health and safety issues were limited framed. • The current CCUS reporting landscape had misperceptions and lacked comprehensive coverage of the value chain. • A science-for-the-community communication strategy that can make media communication effective was proposed. [ABSTRACT FROM AUTHOR]

Deep decarbonisation – i.e. the transition towards net-zero emissions energy systems – will be enabled by a high penetration of intermittent renewables, storage and sector-coupling technologies. In this paper, we present a novel modelling approach to capture the increasing complexity of such future energy systems and help policy makers choose among the different possible transition scenarios. Salient features of our model, consisting of an extended and regionalised version of EnergyScope (Limpens et al., 2019 [1]), are a low computational time and a concise formulation which make it suitable for uncertainty and what-if analyses. As a case study, the model is applied to devise scenarios for the Italian energy transition. Specifically, we develop the first open-source whole-energy system model of Italy and assess the feasibility of its decarbonisation strategy with respect to uncertainties in the deployment of carbon capture and storage (CCS) and renewable technologies. Results show that emissions can be cut by 79%–97% vs. 1990 levels thanks to a radical electrification of the energy system coupled to a wide deployment of renewables and efficient energy conversion technologies. Finally, we discuss the synergies, advantages and disadvantages of our proposed approach with respect to alternative modelling approaches used across 88 recent deep decarbonisation studies. The analysis suggests that our model, thanks to its computational efficiency and a snapshot approach (i.e., modelling a target-year in the future), can complement more detailed and established energy models optimising the energy transition pathway (i.e., modelling the pathway from today to the target year). [Display omitted] • Novel open-source whole-energy system model for deep decarbonisation studies. • Key features: hourly resolution, target-year optimisation, computational efficiency. • Case study: deep decarbonisation of Italy in 2050 under uncertainty. • Results: 79%–97% CO 2 emission reduction is feasible and cost-effective. • Comparison with other models used in 88 recent deep decarbonisation studies. [ABSTRACT FROM AUTHOR]

The sustained rapid growth and learning rates displayed by solar PV and wind electricity generation capacity over recent decades appear to be unprecedented. With these technologies now available at costs competitive with - or below - those of fossil fuel incumbents in many parts of the world, high rates of growth appear likely to continue. In this paper we use 'top-down' extrapolation of global trends and simple and transparent models to attempt to falsify the proposition that PV and wind have the potential to achieve dominance in global primary energy supply by 2050. We project future deployment of PV and wind using a logistic substitution model, and examine a series of potentially fundamental constraints that could inhibit continued growth. Adopting conservative assumptions, we find no insuperable constraints across physical and raw materials requirements, manufacturing capacity, energy balance (EROEI), system integration and macro-economic conditions, to this outcome. We also demonstrate synergy with direct air carbon capture and storage (DACCS) that would allow the achievement of global net-zero CO 2 emissions by mid-century. Achieving such an outcome would require large scale reconfiguration of the architecture of global and regional energy systems, particularly from 2040 onwards. Low cost primary electricity is likely to be a significant factor in driving such a reorganisation. But given the speed and depth of the transition, hurdles will remain that will require foresight and strategic, coordinated action to overcome. • Extrapolating PV and wind deployment using logistic substitution suggests they may dominate global energy supply by 2050. • There are synergies between PV and wind, and DACCS. DACCS adds flexibility to a renewably powered energy system. • This supply-side transformation would both drive and require a wholesale reconfiguration of the rest of the energy system. • With DACCS, this process could reduce net global CO 2 emissions from energy to zero by 2050, and below zero thereafter. • There appear to be no insuperable physical or economic barriers to such an outcome. [ABSTRACT FROM AUTHOR]

National climate targets must be decomposed into key areas to guide mitigation actions. This paper presents a comparative study of China's low-carbon transition pathways at the sectoral level under the nationally determined contribution (NDC) and 2 °C targets, using the energy system model and detailed sectoral information. The results show that each sector plays different roles in terms of emission trends, mitigation potentials, technology roadmaps, investment requirements, and mitigation costs. The power sector is expected to contribute around 50% of the total mitigation. The industry sector has better cost-effective performance, with high mitigation potential and low investment requirement. By contrast, the transport and power sectors account for around 90% of total investment demand. The building and transport sectors have substantial mitigation opportunities that can be realized through technologies with negative mitigation costs. Conversely, the industry sector faces challenges in promoting carbon capture and storage, which has the highest mitigation cost. Compared with the sectoral transition pathways under the NDC target, the 2 °C scenario requires a rapid near-term decarbonization of the power sector and additional emission reductions in end-use sectors. This decarbonization is possible through comprehensive deployment of advanced low-carbon technologies as well as measures that increase investments in low-carbon infrastructure and decrease investments in fossil fuel-based technologies in the power and transport sectors. Therefore, it is important to thoroughly understand the sectoral transition pathways under different climate targets in order to coordinate inter-sectoral actions and resources in a cost-effective manner. • A quantitative study of sectoral low-carbon transition pathways in China was done. • Sectors perform differently in emissions trends, mitigation potential, and cost. • The performance of each sector changes over time and based on climate targets. • Different climate targets imply different technology roadmaps. [ABSTRACT FROM AUTHOR]