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The pressure on reducing greenhouse gas emissions has increased since the focus on climate change mitigation has grown. As the human development index is directly related to per capita energy consumption, sustainable energy production with reduced carbon footprint is the essential pathway for cleaner environment. Over numerous existing biological processes, hydrogen production via photo fermentation and photolysis of water is considered a more sustainable and economical method of hydrogen production. While both biological modes suffer from certain limitations, such as low yields and low production rates, practical implementation is still a long way off due to these limitations. The unique properties of nanomaterials (NMs) can help increase the efficiency of the biomass to biohydrogen process in significant ways. Applications of organic and inorganic nanoparticles in photocatalytic and photo fermentative hydrogen production is discussed in this paper. This review reports a wide range of applications of nanomaterials including the details of photo fermentative microorganisms and their mechanism of action. The maximum photo fermentative bio-H 2 production was reported in the presence of SiC–Fe 3 O 4 (3.02 mol H 2 /mol acetate), Ni (41 mol H 2 /mol sugar), graphite-C 3 N 4 (64.2 mol H 2 /mol sugar) whereas photocatalytic bio-H 2 yield was highest when Pd–Ni/CdS (54 mmol/g.h), Ni-MO/g-C 3 N 4 (1785 mmol/g.h) and CuO/TiO 2 (20.3 mmol/g.h) nanoparticles were employed. To design photocatalytic systems for practical and scalable use, the future research should be focused on deeper theoretical knowledge of mechanisms of light harvesting, ± charge separation and transport, surface biochemical reactions, semiconductor–liquid interactions, and reactor dynamics. [Display omitted] • Recent developments for improving water photolysis and photo-fermentation are reviewed. • Applications of organic and inorganic nanoparticles in hydrogen production are discussed. • The working principle and mechanism of hydrogen production are discussed. • The influence of key operating factors are presented. • Scope for future research was presented. [ABSTRACT FROM AUTHOR]

Deep decarbonization of the transport sector in small island developing states (SIDS) can simultaneously address issues of energy security, high fuel import prices, and climate change mitigation measures while ensuring a reduction in air pollution and higher levels of wellbeing for citizens. Electrification plays a vital role in the decarbonization process. Here, we investigate potential transition pathways towards electrification, taking the public transportation system in Mauritius as an example, where there is vast potential in electrifying the old and overburdened bus system. We simulate a variety of public bus turnover scenarios, considering initial costs of investments, energy and fuel requirements, and reductions in greenhouse gas emissions. We demonstrate that optimized investment into electrifying public transit pays off, with annualized investments of about $5 million superseded by annual savings on fossil fuel imports of about $15 million. We suggest that international donors can accelerate this transition by providing loan guarantees and, by this, reducing the cost of capital. • Public fleet electrification is a straightforward yet widely beneficial approach. • We present a framework for comparing investment costs, energy and fuel requirements and emission reductions. • Investing in large-scale sustainable projects requires substantial amounts of upfront financing. • Optimized investment into electrification proves beneficial due to savings on fossil fuel imports. • A rethinking of global funding mechanisms can provide a way forward in addressing these barriers. [ABSTRACT FROM AUTHOR]

Air pollution control policies in China have been experiencing profound changes, highlighting a strategic transformation from total pollutant emission control to air quality improvement, along with the shifting targets starting from acid rain and NO x emissions to PM 2.5 pollution, and then the emerging O 3 challenges. The marvelous achievements have been made with the dramatic decrease of SO 2 emission and fundamental improvement of PM 2.5 concentration. Despite these achievements, China has proposed Beautiful China target through 2035 and the goal of 2030 carbon peak and 2060 carbon neutrality, which impose stricter requirements on air quality and synergistic mitigation with Greenhouse Gas (GHG) emissions. Against this background, an integrated multi-objective and multi-benefit roadmap is required to provide decision support for China's long-term air quality improvement strategy. This paper systematically reviews the technical system for developing the air quality improvement roadmap, which was integrated from the research output of China's National Key R&D Program for Research on Atmospheric Pollution Factors and Control Technologies (hereafter Special NKP), covering mid- and long-term air quality target setting techniques, quantitative analysis techniques for emission reduction targets corresponding to air quality targets, and pathway optimization techniques for realizing reduction targets. The experience and lessons derived from the reviews have implications for the reformation of China's air quality improvement roadmap in facing challenges of synergistic mitigation of PM 2.5 and O 3 , and the coupling with climate change mitigation. [Display omitted] [ABSTRACT FROM AUTHOR]

Global climate action is the grand challenge of the 21st century. Large reductions in greenhouse gas emissions are needed, with net-zero CO 2 emissions by mid-century a requirement for many scenarios that restrain global warming below 1.5 °C by 2100. This will require massive deployment of renewables such as ground-based solar and wind, increased long-distance grid transmission capacity, and electrification of much of the global economy. Increased electrification, coupled with rising standards of living in developing countries, will drive ever-larger electricity demand to 2050 and beyond. And the intermittency, land-use, and transmission requirements of ground-based solar and wind present challenges to large-scale deployment to meet Net Zero targets. Space-based solar power (SSP) presents an enticing alternative, and with full reusability of upcoming heavy launch vehicles and modular SSP architectures, the economics of deployment are expected to become favorable in the coming decades. Efforts exist today to deploy demonstrators this decade, with initial production systems by 2050. However, deploying SSP at the scale required to address rising, global electricity demand will itself require orders-of-magnitude greater launch frequencies. If heavy launch frequency does not increase quickly enough, due to environmental concerns, launch site competition, or other bottlenecks, the dropping cost of launch will not be sufficient to enable SSP for global impact this century. A space elevator (SE) development program like that proposed by the International Space Elevator Consortium (ISEC) offers an alternative delivery mechanism for scaling SSP beyond 2050, hedging the risk of reliance on a single delivery system while reducing the time required for large-scale SSP deployment. To de-risk possible futures in which SSP is a major part of the global energy mix this century, a dual space access architecture is proposed, leveraging the strengths of heavy launch and SEs together. Such an architecture would secure the future for green energy on Earth, in 2050 and beyond. • Net-zero CO 2 emissions by 2050 required for many climate scenarios with < 1. 5 °C warming. • Massive deployment of renewables and scale-ups of long-distance transmission required. • Space-based solar power (SSP) is becoming economically viable as an enticing alternative. • Reusable heavy launch must scale-up rapidly to deploy SSP at scale for net-zero. • A space elevator development program would de-risk delivery of SSP at scale. [ABSTRACT FROM AUTHOR]

Cocoa production is a leading driver of deforestation in the humid-tropics of West Africa. Reconciling climate change mitigation with livelihoods of farmers requires identification of production strategies to concurrently improve yield and profit while curtailing emissions of greenhouse gases (GHG). Using a 2021 plot-survey conducted in Ghana's Eastern region, we evaluated yields, GHG emissions, and value of production (VOP) (a profit indicator) across a typology representing the diversity of systems at plot-level. The typology was constructed by first stratifying plots according to shade levels and variety (hybrid vs. Amazonia) which resulted in three systems: Hybrid sun , hybrid variety under full-sun (little to no shade); Hybrid shade , hybrid and moderate shade (13–25 shade trees ha−1); and Amazonia, Amazonia under predominantly moderate shade. Next, factor analysis and clustering were used to group plots within each system according to cocoa yield, vegetation, management, and (local) climate conditions. Cluster analysis showed that fertiliser, weeding, pruning, hand pollination, cocoa tree density, and shade tree densities of differing heights were most influential for determination across systems. Hybrid shade had the highest net GHG removal rate at −6.8 ± 1.7 (± 95% CI) Mg CO 2 eq ha−1 yr−1: 48% and 127% higher (emissions more negative) respectively over Amazonia and Hybrid sun. Hybrid shade additionally had the highest average and least variable VOP among production systems at 669 ± 564 USD ha−1 yr−1, compared to Hybrid sun and Amazonia at 404 ± 442 and 213 ± 280 USD ha−1 yr−1 respectively. These results point to hybrid cocoa grown under moderate shade of 13–25 shade trees ha−1 as optimal for reconciling climate change mitigation with development in West African cocoa. • Study concurrently evaluates financial profits and GHG balances (N 2 O & CH 4 emissions, CO 2 removals) in West African cocoa. • Plot-level indicators are evaluated across a typology obtained from sample-stratification and clustering. • Hybrid cocoa under moderate shade (13-25 shade trees ha-1) had GHG removal increment of 127% over same variety without shade. • This system too had higher mean profits, thus best reconciling GHG mitigation and economic development for the region. [ABSTRACT FROM AUTHOR]

Achieving decarbonisation of the heating sector is a major challenge, especially in Ireland, which has the lowest proportion of renewable heat in Europe. In economically pursuing ambitious and equitable climate targets, Ireland's Climate Action Plan 2023 set a goal of reaching 2.5 TWh of district heating by 2030, starting from a limited existing capacity. This pioneering study explores supply sources and heat density demand cohorts to develop a model to understand district heating in a low-deployment region, using Ireland as a case study. We also conduct a sensitivity analysis considering different connection rates. Our research demonstrates that district heating is pivotal in achieving optimal decarbonisation pathways. Incorporating district heating reduces marginal CO 2 emission prices by 13%–25%. Additionally, with feasible growth limits applied, total savings for the energy system are anticipated to reach €17.2 billion by 2050. This reduction of emissions in the building sector, facilitated by district heating, allows for greater emissions allowances in other sectors and reduces reliance on electricity while meeting climate targets. These insights highlight the need for spatial energy policies and deepen our understanding of integrating district heating within an energy system optimisation model. • District heating in Ireland can reduce marginal CO 2 emission prices by 13%–25%. • District heating can cumulatively save €17.2 billion compared to no district heating. • Regional energy policy is needed to align with cost-optimal pathways. • Regional supply and demand quantified sensitivity analysis strengthens insights. [ABSTRACT FROM AUTHOR]

Efforts to enhance greenhouse gas (GHG) emission reduction in East Asia play a pivotal role on both global and regional scales in advancing climate mitigation strategies. This study aimed to better constrain anthropogenic CO 2 emission estimates by expanding the network of near-surface in-situ stations for CO 2 observations across South Korea. To achieve an optimal CO 2 network design, we conducted an Observing System Simulation Experiment (OSSE) coupled with the Stochastic Lagrangian Transport model (STILT), utilizing meteorological data from the Korean Integrated Model (KIM). Our inversion setup incorporated two CO 2 emission datasets with a 0.1o resolution: EDGAR v6 for prior emissions and GRACED for truth emissions. A uniform model-mismatch error of 3 ppm was introduced across sites. The effectiveness of the existing five in-situ stations, termed the base network, in South Korea was evaluated to gauge their ability to constrain CO 2 surface flux estimates. However, the findings revealed a reduction in flux uncertainty of only 29.2%, which fell short of the desired uncertainty reduction goal. In this base network, the Lotte World Tower (LWT: 37.5126°E, 127.1025°E) in Seoul and the Anmyeondo (AMY: 36.538576° N, 126.330071° E) site in Taean county stood as major contributors, with estimated reductions of 17.48% and 6.35%, respectively. Consequently, we proposed and developed an extended network, identifying seven candidate sites based on consideration of logistical factors, existing infrastructures, and proximity to the emission source regions. An incremental optimization scheme ranked their contributions, resulting in an additional 25% reduction, bringing the total to 54.13%. However, it is noteworthy that diminishing returns (ranging from 13% to less than 0.1%) were observed with an increase in station count mainly due to the possibility that adding a station earlier in the sequence might render subsequent stations redundant. Despite this, the proposed CO 2 network successfully reduced uncertainty in emissions, narrowing the gap with the objectives of the Global Greenhouse Gas Watch (G3W). • Designing CO 2 near-surface observation network over South Korea. • New stations selected considering logistic factors, existing infrastructures, and proximity to emission sources. • The base network was able to reduce 29.18% of the uncertainty in CO 2 emissions. • Extending network, by adding new seven candidate sites, led to a total uncertainty reduction of 54.13%. [ABSTRACT FROM AUTHOR]

• Attractive names can increase the appeal of plant-based meals. • Appeal scores for plant-based meals are associated with plant-based choices. • Appealing names might increase plant-based choices among flexible meat eaters. Reducing meat consumption could materially reduce global greenhouse gas emissions. Yet, meat consumption habits are exceptionally difficult to break, even more so when plant-based meals are described using unappealing names. Past interventions that attempted to alter consumer choice by changing meal names at restaurants reported only modest effects. We propose that interventions aimed at increasing demand for plant-based meals may be more effective if: (1) meal naming is informed by theory; (2) the affective appeal of meal names is tested before deployment; (3) meat-based meal names are deliberately kept basic; and (4) heterogeneity of different meat-eater segments is accounted for. We conduct three studies. Study 1 evaluates the appeal of several alternative theory-informed names of plant-based meals, highlighting taste, provenience, and/or texture. Study 2 assesses the effectiveness of appealing names on stated plant-based choices across the general Australian population, and Study 3 for market segments of meat-eaters. Results indicate that highlighting flavour, provenience, and texture can impact the appeal of plant-based meals. Increased appeal does not translate to increased plant-based meal choices across all consumers but does have a potential impact for a specific group of more flexible meat-eaters. We conclude that using appealing names for plant-based dishes on restaurant menus may represent a cost-effective way to entice specific market segments of consumers to choose plant-based rather than meat-based dishes when dining. With food contributing nearly 25% to global emissions, changing meal choices for even the smallest of market segments can make a meaningful contribution to climate change mitigation. [ABSTRACT FROM AUTHOR]

Superblocks are traffic-calmed neighborhoods that contribute to climate change mitigation and improve living and health conditions of inhabitants without requiring extensive reconstructions. This article investigates experiments with superblocks in Vienna (Austria) from initial discussion to the first experimental implementation. We use an integrated mixed-method approach: First, we examined potential climate and health benefits of three hypothetical superblock sites through transport modeling. We then conducted stakeholder interviews at two points of time to investigate the perceived acceptance of superblocks and to examine how superblock experiments align with the conventional planning regime, thereby focusing on actor's composition, dominant discourses, and mode of governance. The modeling results suggest that reductions in greenhouse gas emissions and public health benefits are 2–3 times higher when superblocks are implemented in more deprived compared to more affluent urban areas. In the course of implementing the first superblock experiment in Vienna, the discursive reframing of superblocks as a redistributive intervention, which we could trace through the interviews, resulted in implementing the pilot project in a district with the most beneficial sustainability outcomes. • From discussion to implementation: investigating Vienna's superblock experiments. • To derive potential climate and health benefits we applied transport modeling. • To derive drives of superblock implementation we conducted interviews. • Potential climate and health outcomes are the highest in more deprived urban area. • Superblocks became re-framed as a redistribution intervention. [ABSTRACT FROM AUTHOR]

Carbon neutrality strategies have a significant role in climate mitigation efforts. As global concerns regarding climate change continue to increase, achieving carbon neutrality has emerged as a paramount objective for reducing greenhouse gas emissions and limiting the adverse impacts of anthropogenic activities on the environment. This research investigates a wide range of scholarly works to conduct an in-depth analysis and synthesis of the relevant information about carbon neutrality strategies. The review introduces carbon neutrality principles and terminologies, highlighting their importance in climate mitigation. It then proceeds to explore the wide range of strategies employed across different sectors and industries, investigating their effectiveness, scalability, and potential challenges. A multidimensional analysis contrasts the United States Nationally Determined Contributions pathway 2023, China's Nationally Determined contributions 2023, and the EU Directive 2023/2413, assessing their economic, environmental, political, and social impacts. The study evaluates strategies' effectiveness, scalability, and innovation for transitioning to a sustainable, low-carbon future. It fills a gap by analyzing global approaches across the US, China, and the EU, which account for about 50% of the world's total GHG emissions. It evaluates the novel application of diverse strategies, from renewable energy transitions to innovative policy measures, highlighting their potential to mitigate climate change effectively. By providing a multidimensional analysis of these strategies' impacts, the research not only enhances understanding of effective carbon neutrality tactics but also underscores the importance of international cooperation in realizing a sustainable, low-carbon future. • Identifies and analyzes carbon neutrality strategies, emphasizing the need for diverse US, Chinese, and EU approaches. • Evaluate renewable energy, carbon capture, and policy tools for carbon reduction effectiveness, scalability, and innovation. • Highlights the study's novelty in synthesizing current knowledge on carbon neutrality, addressing a significant research gap. • Concludes with strategic ideas for international collaboration and policy development for low-carbon futures. [ABSTRACT FROM AUTHOR]

The Chinese government has announced ambitious carbon reduction goals to address climate change, however, there has been limited scientific attention to the achievement of deep decarbonization in regions with insufficient economic development. Moreover, the complex impacts of climate change mitigation on energy system, environment and economic development remain unclear in Northwest China. Here we construct a comprehensive evaluation model system to evaluate the effects of different climate mitigation pathways in Qinghai, Ningxia, Gansu and Xinjiang provinces. Results show that the four provinces need to vigorously increase the share of electricity that consumed in final energy to 53.1–60.0% and 52.9–62.0% for 2 °C and 1.5 °C target, respectively, and reduce total energy demand to 11.6–44.4 Mtoe and 8.2–34.1 Mtoe in 2050. Meanwhile, the CO 2 emissions for their energy systems will reach peak by 2025 at lower values. Moreover, the synergies of CO 2 reduction are most conducive to abating SO 2 pollution and also contributing to decreasing PM 2.5 concentrations. Additionally, the GDP losses in 2050 fluctuate from 5.0 to 21.7 billion USD in the 2 °C scenario to 11.5–52.7 billion USD in the 1.5 °C scenario. Our study provides practical guidance on achieving carbon reductions in less developed regions of China and lays foundations to promote decarbonization of energy systems in other provinces. • Realizing climate goals requires low-carbon energy systems led by electricity. • Energy-related carbon emissions in Northwest China will peak by 2025. • More ambitious climate and clean air policies are needed for air quality improvement. • Economic loss shows an upward trend in the future under climate targets. [ABSTRACT FROM AUTHOR]

This study investigates the impact of alternative fertilization practices on the yield-scaled global warming potential (YS-GWP) in almond orchards. Almond production is a contributor to greenhouse gas emissions, primarily due to nitrogen-based mineral fertilizers. This research aims to identify strategies that reduce the environmental footprint of almond cultivation while maintaining yield. Field experiments were conducted in an almond orchard using three alternative fertigation practices: Advance Grower Practice (AGP), Pump and Fertilize (P&F), and High Frequency Low Concentration (HFLC). AGP is the current practice used by producers to meet annual N demand for almond tree growth; P&F is a reduction in applied N rate in response to measured N concentrations in the groundwater so that the added N and groundwater N reach the same total N applied; HFLC is a practice of applying smaller N rates per individual event. HFLC uses a greater number of fertigation events to reach similar total annual N load as other treatments. Cumulative N 2 O and CH 4 emissions were used to determine GWP by converting the emissions to carbon dioxide equivalents (CO 2 eq) within a 100-year horizon. Nitrous oxide emissions were multiplied by a radiative forcing potential CO 2 eq of 298 and CH 4 by 25 (UNFCCC, 2007). The results revealed that both P&F and HFLC reduced the YS-GWP compared to AGP. HFLC demonstrated 52–78% decrease in GWP per unit of almond yield compared to AGP, while P&F showed 48–58% decrease over AGP. These reductions were attributed to the reduced nitrous oxide emissions associated with P&F and HFLC. Further, P&F and HFLC tended to have higher N use efficiency than AGP. We demonstrate that adopting alternative fertilization practices can effectively mitigate the environmental footprint of almond orchards while maintaining crop yields. These practices offer viable options for almond growers to reduce greenhouse gas emissions, enhance sustainability, and contribute to climate change mitigation. • Applying nitrogen fertilizer at a lower amount and higher frequency reduces nitrous oxide emissions. • This practice tends to have higher nitrogen use efficiency than standard practice. • It maintains commercial yields at the same level as the standard practice. • It lowers Yield Scaled Global Warming Potential more than the standard practice. [ABSTRACT FROM AUTHOR]

• Substitution factors for forest products for the Canadian context were developed. • Substitution factors ranging from 0.51 to 0.91 tC/tC were found. • They will lead to more accurate assessments of the forest GHG mitigation potential. • These factors will help governments to manage forest and fight climate change. Evaluating the climate change mitigation potential of the forest sector requires a holistic approach based on forest carbon (C) sequestration, C storage in harvested wood products (HWP) and substitution on markets. High uncertainty is associated with substitution factors, that express avoided fossil greenhouse gas (GHG) emissions from the use of forest-based products in replacement of GHG-intensive materials and fossil fuels. Few studies have focused on the development of substitution factors in Canada, resulting in the use of unrepresentative generic data. Here, we provide a framework to reduce uncertainties related to substitution factors for primary wood products in a Canadian context. A life cycle assessment framework is used to quantify fossil GHG emissions for a baseline and a wood-intensive scenario. For solid product substitution, we focused on the construction sector and analyzed a range of innovative wood buildings with steel and reinforced concrete as alternative materials. We found non-weighted averages of 0.80 tC/tC for sawnwood and 0.81 tC/tC for panels. For energy substitution, we analyzed cases with different specifications on biomass product, facility type and alternative fossil fuel source in non-residential heat production and biofuel transportation sectors. We found a non-weighted average of 0.80 tC/tC for non-residential heat production and 0.51 tC/tC for biofuel transportation, that can be interpreted as 0.91 tC/tC for heavy fuel oil, 0.69 tC/tC for light fuel oil and 0.68 tC/tC for natural gas substitution. These results provide a benchmark for substitution factors in Canada, to help guide forest management strategies for climate change mitigation. [ABSTRACT FROM AUTHOR]

Southeast Asia (SEA) is a key producer and exporter of rice, accounting for around 28% of rice produced globally. To effectively mitigate greenhouse gas (GHG) emissions in SEA rice systems, field methane (CH 4) and nitrous oxide (N 2 O) emissions have been intensively studied. However, an integrated assessment of system-level GHG emissions which includes other carbon (C) balance components, such as soil organic carbon (SOC) or energy use, that can positively or negatively influence the net capacity for climate change mitigation is lacking. We conducted a systematic review of published research in SEA rice systems to synthesize findings across four main components of net system emissions: (1) field GHG emissions, (2) energy inputs, (3) residue utilization beyond the field, and (4) SOC change. The objectives were to highlight effective mitigation opportunities and explore cross-component effects to identify tradeoffs and key knowledge gaps. Field GHG emissions were the largest contributor to net system emissions in agreement with existing scientific consensus, with results showing that practices such as floodwater drainage and residue removal are sound options for CH 4 mitigation. On the other hand, increasing SOC potentially provides a large GHG mitigation opportunity, with long-term continuous rice cropping and practices such as residue incorporation and biochar application promoting SOC increase. A reduction in energy inputs was mainly achieved by optimizing agrochemical use, especially N fertilizers. For residue utilization beyond the field, GHG emission mitigation mainly came from preventing open field burning through residue removal. Removed residue can subsequently be used for producing energy that offsets GHG emissions associated with conventional fuel sources (e.g. fossil fuel-based electricity generation) or substituting material used in other production systems. Integrating all four components of net system emissions into one analysis underscores the following two main takeaways. First, the components of field GHG emissions and SOC change are the biggest opportunities for reducing net system emissions and need to be considered for effective climate change mitigation. Second, the reduction of C inputs through residue removal and increased soil aeration through multiple drainage will lower CH 4 emissions but may also potentially decrease SOC stocks over time. Hence, we argue that future research needs to consider cross-component effects to optimize net system emissions, specifically the "stacking" of best management practices for mitigation related to field GHG emissions or SOC change in long-term experiments. • Net system emissions include field CH 4 /N 2 O emissions, energy inputs, residue utilization, and SOC change. • Integrated review highlights cross-component effects of management including tradeoffs. • Field GHG emissions and SOC change are the largest opportunities for mitigation. • Reduced C inputs and drainage decrease CH 4 emissions, but may negatively affect SOC. • "Stacking" of best management practices is a key knowledge gap that warrants research. [ABSTRACT FROM AUTHOR]

Identifying transmission sectors that may not be revealed by existing indicators, such as production-based emission (PBE) and consumption-based emission (CBE) accounting, is significant in emission reduction policies and provides insights into novel opportunities for companies and industries to reduce emissions. This study proposed an intermediate-based emission (IBE) accounting approach that considers indirect emissions from intermediate goods production and a case study was conducted using Exiobase 3.8. The highest IBE sector was 'basic iron' (1131 Mt-CO 2), and the sector's IBE was higher than its PBE (1052 Mt-CO 2). Additionally, the material sector, such as aluminum products (326 Mt-CO 2), was identified as a key transmission sector, although PBE (21 Mt-CO 2) and CBE (3 Mt-CO 2) of the sector is very low. In addition, IBEs were observed to be closely related to overall supply chain emissions in Germany, Japan, and Asia, and cooperation is required to reduce the emissions. The method enables approaching supply chains with large emissions from three perspectives (production-, consumption-, and intermediate-based accounting) and exploration of the emission reduction responsibilities of the three key sectors. The utility and discussion of the approach are consistent with Scope 3 emissions and facilitate fair allocation of emission reduction responsibilities to a larger number of countries and industries. • This study suggested intermediate-based emission (IBE) accounting. • Industries such as basic iron have high production–based emissions but higher IBE. • Intermediate industries not focused on by existing emission accounting identified. • Existing betweenness-based emission accounting much higher than actual emissions. • Germany, Japan, and Asian HEMs have strong correlation with IBE. [ABSTRACT FROM AUTHOR]

Malaysia is actively addressing environmental responsibilities by pledging a 45 % reduction in greenhouse gas emissions by 2030, aided by a large-scale solar photovoltaic initiative. Nonetheless, the unprecedented meteorological events due to climate change such as extreme temperatures and precipitation may reduce the large-scale solar performance and lead to infrastructure damage. The primary objective of this study is to conduct a screening-level analysis from both technical and economic perspectives, in order to assess the effects of extreme temperature and precipitation on large scale solar in Malaysia. This study hypothesized that extreme temperature and precipitation reduce large scale solar performance and increase infrastructure damage. The results demonstrate that both extreme temperature and precipitation increase the power and efficiency loss over time. In general, infrastructure damages caused by extreme temperature and precipitation can result in degradation, a shortened lifespan, and ultimately a collapse. In this study, the costs of physical damage were estimated using the modified levelized cost of energy, and it was found that the cost of physical damage in extreme temperature conditions was approximately 30 % greater than the cost in extreme precipitation conditions, which was nine times greater than in normal condition. Compared to a no-adaptation scenario, it is possible to reduce the additional costs due to extreme temperature and precipitation by up to 53 % and 49 %, respectively. Enhancements, additional analysis, and validation of these findings could aid in the readiness for climate change mitigation efforts, not only for solar power systems but also for other types of energy systems. [Display omitted] • Generic screening-level analysis for assessing techno-economic impact of solar. • Extreme temperature and precipitation reduce solar performance and increase damage. • Study employs modified levelized cost of energy to estimate physical damage costs. • A proactive adaptation strategy reduced the additional cost for both scenarios. [ABSTRACT FROM AUTHOR]

Carbon emission reduction in China matters to global climate change mitigation. China has been experiencing extensive land changes, which profoundly influence terrestrial ecosystem carbon storage (TECS) and carbon emissions. Scholars have predicted influences of land changes on TECS in China with scenarios obtained from global integrated assessment models (IAMs), which lack national details. Moreover, universally existing variations in land-use intensity have not been considered when estimating influences on TECS. This study simulated changes of land-use intensity of China from 2000 to 2050 using CLUMondo under China-specified policies for sustainable development modeled by a national IAM named Threshold21-China. We proposed a more precise TECS estimation method by distinguishing land-vegetation and land-soil types. Results demonstrated that under scenario with preceding policies, the total TECS can increase by 865.5 Tg C from 2000 to 2050. Through implementing preceding policies, TECS loss by conversions from cultivated land to artificial surfaces can decline by 82 Tg C, and new TECS accumulated by increased and densified forests can increase by 73 Tg C. Mountainous and rapidly urbanizing regions are sensitively influenced and need more restrict land change management policies. This study demonstrates the significance of sustainable development policies for TECS conservation and indicates specific critical regions. • Introducing national IAM into land change simulation. • Considering land-use intensities in land change simulation. • Proposing an improved TECS estimation method. • Estimating influences of land changes on China's TECS. • TECS accumulation could be improved under sustainable policies. [ABSTRACT FROM AUTHOR]

Sub-Saharan Africa is a region with a large population living without electricity. This study investigates the grid balancing role of bioenergy in a sub-Saharan Africa's fully renewable power sector to address the energy poverty challenge in the region, using Ghana as a case country. Two methods are employed: the bioenergy estimation method, for deriving Ghana's technical bioenergy potential, and the LUT model, for the power sector transition modelling. The Ghanaian bioenergy potential of 48.3 TWh is applied on the power sector using the LUT model to develop six alternative scenarios, emphasising on the role of bioenergy, greenhouse gas emissions costs, and climate change mitigation policies. The results of the Best Policy Scenario reveal that with an electrical efficiency of 37.2%, 18 TWh of electricity, which is 16.9% of Ghana's electricity demand by 2050, could be produced from bioenergy for grid balancing. Also, the levelised cost of electricity declines from 48.7 €/MW in 2015 to 36.9–46.6 €/MWh in 2050. Whereas the cost of electricity increases to 76.4 €/MWh in the Current Policy Scenario without greenhouse gas emissions costs. The results show the viability of a relatively cheap and bioenergy balanced sustainable renewable power system for the sub-Saharan African region. • The role of modern bioenergy is examined in renewable energy (RE) dominated power systems. • A comprehensive bioenergy potential assessment for the case of Ghana is presented. • Bioenergy provides flexibility in hybrid solar PV-battery dominated power systems. • Levelised cost of electricity for 100% RE ranges from 37 - 46.6 €/MWh in 2050. • Sustainable modern bioenergy contribution in power systems substantially reduces system costs. [ABSTRACT FROM AUTHOR]

Decarbonisation strategies for eight German manufacturing companies of different industries (electrical, chemical, beverage, mechanical engineering, automotive, polymer processing) are developed and analysed. The abatement potential and economic feasibility of strategies depend to a large extent on individual preconditions e.g., the area available for renewable energy systems, and dynamic effects, for example the changing emission intensity of local electricity generation. The strategies lead to a reduction of between 41 % and 88 % for seven of the eight companies. The in-depth case studies show that energy efficiency measures and expanding the company's own renewable energy plants, except for solar heat, are particularly cost-effective, while shutting-down existing combined heat and power plants has the highest abatement costs between 169 and 1686 EUR/tCO 2 e. Decarbonising electricity procurement and switching from natural gas to biomethane have the highest greenhouse gas abatement potential in Scope 1 and 2. The novelty of this work is the linking of economic and ecological considerations of measures in the context of company-specific decarbonisation strategies. Using marginal abatement cost curves, different options for emission reductions are discussed and general conclusions for the development of decarbonisation strategies in the manufacturing sector are drawn. [Display omitted] • In-depth decarbonisation strategies are developed for eight manufacturing companies. • Abatement potential and economic feasibility depend largely on dynamic effects. • Energy efficiency and own renewable generation capacity are most cost-effective. • Marginal abatement cost curves link economic and ecological potential. • Greenhouse gas abatement costs are quantified for different industries. [ABSTRACT FROM AUTHOR]

The depth and breadth of the climate crisis is well known, all sectors, industry, government and the individual have the potential to reduce emissions to slow or stop catastrophic climate change. To determine and evaluate the (revealed) preferences of the public in reducing their personal carbon emissions, a conjoint analysis survey, using the PAPRIKA (Potentially All Pairwise RanKings of all possible Alternatives) method, was distributed to the public in a city in the south of England (Southampton). Knowledge of the deep-seated preferences of the public makes a fundamental contribution to future climate actions because it enables publicly acceptable system change to be developed. Results showed the public were unwilling to make large-scale lifestyle changes, even if they would cause large emission reductions. There was a clear preference for making relatively easy, convenient changes to behaviour rather than making more difficult personal lifestyle changes involving diet and transportation. A significant value-action gap is evident, with the public showing high awareness of the seriousness of climate change but showing an unwillingness to make deep cuts to their personal emissions. Demography and personal factors had a relatively low influence over preferences with trends generally staying the same across demographic groups, aside from income brackets. Participants believed that reductions in emissions should come from a 'group effort' from all levels of government, business, environmental groups and individuals. Few participants placed themselves as individual drivers of carbon emission reduction. In order to reduce emissions some form of intervention needs to be made, as the public are not personally willing to make large-scale reductions in carbon emissions, regardless of their environmental awareness or demography. • Public's views on approaches to carbon reduction investigated via conjoint analysis. • Preference for low intensity, 'easy' behaviours not challenging lifestyle changes. • Demographic & personal factors have low influence on carbon reduction preferences. • High awareness of severity of climate change, impacts/priority; also high anxiety. • Desire to consume & "carry on as normal" outweighs self-reported concerns/attitudes. [ABSTRACT FROM AUTHOR]

Reducing greenhouse gas emissions as a key mitigation strategy for climate change has become a global consensus. Remote work, which has good carbon footprint reduction potential, is widely considered a sustainable working mode. However, it is still unknown the extent to which occupations and means to work may influence the pathways of carbon footprint reduction from remote work when interacting with income groups of populations. This study investigates whether optimizing low-carbon scenarios centered on remote work in four major U.S. cities impacts inequality between high and low-income populations. Firstly, we employ an emissions coefficient methodology to quantify the per capita carbon footprint reductions achieved by remote workers within Census Block Groups (CBGs). Secondly, we estimate the decarbonization potential of remote work across urban areas, crafting an optimized scenario that strikes a balance between carbon footprint reduction objectives and urban economic development. This scenario entails transitioning a minimal number of workers from on-site to remote work. Lastly, we analyze the implications of this scenario on high and low-income groups. Our findings suggest that within the constructed low-carbon scenario, low-income individuals are predominantly employed in professions with limited remote work opportunities. Paradoxically, they shoulder a more substantial burden in terms of carbon reduction efforts, underscoring the challenges faced by low-income populations in diminishing their carbon footprints. Consequently, our study offers fresh empirical insights for researchers and policymakers to evaluate the equity aspect of remote work's carbon reduction potential, highlighting the disproportionate challenges faced by low-income groups. In formulating remote work carbon footprint reduction strategies, it is crucial to strike a balance between carbon footprint reduction allocation and other socio-economic costs, while also exploring feasible pathways and actions to attain these goals. [Display omitted] • Leverage remote work as an urban carbon footprint reduction measure. • Cities rely on car commuting have better carbon reduction potential for remote work. • Low-income populations bear more burden in telework carbon reduction process. • The decarbonization process needs to consider the impact of low-income populations. [ABSTRACT FROM AUTHOR]

Deep decarbonization scenarios indicate a decline in fossil oil usage in the coming decades, meaning that oil refineries must adapt. This work evaluates the refining sector in deep decarbonization pathways using Brazil as a case study. BLUES – a national integrated assessment model – is employed to investigate the evolution of the sector in mitigation scenarios until 2050. The production of feedstocks for the petrochemical industry, of fuels for the aviation and maritime sectors, and biomass co-processing are analyzed. These strategies may bring resilience to the sector. The potential for avoiding emissions in refineries' operations is also explored. Findings show that the refining sector operates at 70% and 74% of its nameplate capacity in decarbonization scenarios. These results are used as the starting point for a detailed analysis of Brazilian refineries. Results show that the employment of refineries' assets for purposes aligned with decarbonization targets, along with emissions mitigation in the sector, reduces risks of carbon lock-in and of asset stranding. To our knowledge, this is the first study that evaluates emissions mitigation in the refining sector and also uses an integrated assessment model to investigate oil refining repurposing and co-processing options in the context of decarbonization. • The refining sector is evaluated using an integrated assessment model for Brazil. • A comparison is made between business- as -usual and decarbonization scenarios. • Opportunities for refineries' assets and mitigation measures are explored. • Opportunities for refineries depend on their location and type of processing units. • Risks of carbon lock-in and asset stranding can be reduced. [ABSTRACT FROM AUTHOR]

Rapidly increasing catastrophic environmental incidents and changes in global climate have compelled researchers to take proactive measures for climate change mitigation. Consequently, reducing greenhouse gas emissions has become one of the most significant global targets. The transportation sector has a massive carbon footprint accounting for 22% of the total carbon dioxide emissions. In this regard, road transport contributes the largest fraction of the total emissions within the transportation sector. Conversely, the railway which is the cleanest form of transportation contributes slightly more than 1% of the total emissions. Moreover, since most of the rail systems are operated by government or private companies, it is relatively convenient to implement policies and replace conventional technology with environmentally friendly ones. This could be achieved by taking certain measures from technical and operational viewpoints for conserving energy to lower the carbon intensity of all transport modalities. Hence, this review paper focuses on investigating the railway sector to encourage a modal shift to the least carbon-intensive option. This study provides a critical review of the past and present rail technologies in terms of the environmental, economic, social, and technical perspectives. Moreover, a comparative assessment of the various locomotive types has been performed. The results reveal that battery-hydrogen hybrid locomotives are the best choice to be considered as a future locomotive technology. Hydrogen locomotives have the potential to be a promising alternative to diesel railway locomotives. However, certain technical barriers need to be overcome to enhance the overall system's performance and reliability to further improve the viability of its deployment in the railway sector. [Display omitted] • A critical review of the various rail technologies is provided through different viewpoints. • The assessment constitutes environmental, economic, social, and technical perspectives. • A decision-support tool for comparison of four rail technologies is also developed. • Battery-hydrogen hybrid locomotive results in the highest score of 1.47. • Standalone hydrogen locomotive results in the second highest score of 1.38. [ABSTRACT FROM AUTHOR]

Impacts of commercial aircraft operation upon the environment, which are caused primarily from emissions of C O 2 , N O x and the formation of contrails, are matter of growing concern, as aviation is one of the fastest developing industrial sectors worldwide and the awareness of its effects is expanding. Recent research has focused on the cost-benefit potential of different mitigation strategies, which optimize flight trajectories with respect to climate and economy, but most of these mitigation strategies cannot be implemented in the near future due to technical challenges. The objective of this paper is to present an interim mitigation strategy, which bridges this time period. In analogy to military exclusion zones, climate restricted airspaces (CRA) are defined based on 3-D climate change functions, characterizing the environmental impact caused by an aircraft emission at a certain location. Regions with climate costs greater than a threshold value are closed in the corresponding month; others are cleared for air traffic. To estimate the cost-benefit potential of this strategy, a preliminary analysis is conducted on the route from Helsinki (EFHK) to Miami (KMIA). Affected flight trajectories are re-routed optimally around resulting CRA with regard to monetary costs for varying threshold values. Therefore, flight simulation algorithms are developed, which solve a non-linear optimal control problem. For each optimized flight trajectory corresponding average temperature response (ATR) and cash operating costs (COC) are expressed relative to a reference great circle trajectory with constant Mach number and compared with the climate mitigation potential of climate optimized trajectories. [ABSTRACT FROM AUTHOR]

The main objective of this study is to analyze and compare greenhouse gas emission profiles, dynamics thereof, and the climate change mitigation efforts of the major players in the global climate change arena, namely the G7 and BRICS countries that are accounting for more than 60% of the world greenhouse gas emissions as in 2017. Given that the energy sector is the major source of the greenhouse emissions in these countries, the framework of sustainable energy development indicators was applied to the comparative analysis. The analysis revealed the differences among the groups of countries in terms of greenhouse gas emission profiles and development trends of these profiles. The convergence of greenhouse gas emission profiles can be noticed between G7 and BRICS countries during 1990–2017 period. Greenhouse gas emissions per capita has decreased in G7 countries and increased in BRICS countries. Energy intensity, economic growth and carbon factor are the main drivers of greenhouse gas emissions per capita growth in both groups of countries. Carbon factor represents carbon intensity of a country's energy sector and is measured by greenhouse gas emissions per unit of total primary energy supply. The impact of carbon factor was least significant among the main drivers in both groups. Energy intensity was the major driver of decrease in greenhouse gas emissions per capita for both groups, however, the economic growth exceeded the contribution of energy intensity in BRICS countries and greenhouse gas emissions have increased in this group during investigated period. The comparative analysis of greenhouse gas emission profiles development trends and the main drivers of these trends in both groups of countries provides important insights in shaping future climate change mitigation policies and developing greenhouse gas emission reduction targets. Due to the high greenhouse gas profiles, low GHG reduction commitments and insufficient climate change mitigation the Perform, Achieve and Trade (PAT) scheme in India efforts in both groups there is danger of postponing implementation of Paris commitments and achieving the 1.5° target. The policies implemented in high ranked countries, like or Integrated Resources Planning in South Africa or measures under Energy efficiency directive in EU can be applied in low ranked countries by providing the substantial contribution to the country's climate targets. Image 1 • The GHG profiles of G7 and BRICS were converging during 1990–2017. • GHG/capita has decreased in G7 countries and increased in BRICS countries. • Energy intensity, economic growth and carbon factor - the main drivers of GHG/capita. • Energy intensity - the major driver of decrease in GHG/capita for both groups. • However, the economic growth exceeded the contribution of energy intensity in BRICS. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the decoupling status and mitigation potential of CO2 emissions from China's transport sector over the period 1991–2015. Firstly, this paper utilizes the Log-Mean Divisia Index (LMDI) technique to identify influencing factors, which govern CO2 emissions from China's transport sector. Over the study period, the CO2 coefficient effect (Δ C c f t ) was the main factor for decreasing CO2 emissions. However, the economic growth effect (Δ C g t ) was the main factor for increasing CO2 emissions. Then, the decoupling indicator is also constructed based on the above influencing factors, which can be utilized to reflect the dependence degree of economic development on CO2 emissions from China's transport sector. During 1991–2015, the CO2 emissions from China's transport sector presented expansive coupling (EC) with economic development. Weak decoupling (WD) only appeared in the sub-period 1991–1995. The CO 2 emissions only presented 3 decoupling grades in all sub-period and the period 1991–2015: Ⅱ, Ⅲ, and Ⅳ. Furthermore, the above influencing factors are also used to establish a theoretical mitigation model, which is used to reflect the mitigation potential of CO2 emissions from China's transport sector. Finally, the occurrence of CO2 mitigation only appeared in 3 sub-periods: 1991–1995, 2005–2010, and 2010–2015. • The LMDI technique is used to identify influencing factors. • The decoupling indicator is constructed based on the influencing factors. • The influencing factors are used to establish a theoretical mitigation model. [ABSTRACT FROM AUTHOR]

• We quantified wood substitution benefits in the furniture sector for China. • Displacement factor is used to assess substitution effects on emission reduction. • The avoided emissions for the products were weighted by consumption statistics. • Each tC in wood used for material substitution reduces 1.46 tC of emissions. Wood and wood-based products have positive effects on climate change mitigation. These products can substitute for energy-intensive products made of conventional materials. The main objective of this study was to quantify substitution benefits of wood furniture for China via national-scale mitigation analyses. We selected a basket of representative furniture and estimated the emission reduction for two functionally equivalent products, which differentiate in wood intensity. The emissions avoided in each type of product were weighted by its share of the furniture market to ensure that the basket can represent the current situation. Then, avoided emissions were estimated for wood commodities contained in the products basket. Results demonstrated that wood materials exerted low environmental impacts. From the less to the more wood intensity products with the equivalent function, the proportion of energy-intensive materials decreased 24% while the proportion of their greenhouse gas (GHG) emissions decreased 34%. The overall displacement factor for the wood material was 2.67 kg CO 2 eq/kg or 1.46 tC/tC. The findings highlight the importance of material selection in mitigating climate change in the furniture sector. It is urgent to use of the existing timber resources efficiently and pursue alternative schemes for emission reduction to achieve the goal of GHG mitigation. [ABSTRACT FROM AUTHOR]

Rapid climate change mitigation requires carbon sequestration in addition to greenhouse gas emission reductions. Agriculture may have a high potential for carbon sequestration due to improved practices. However, it is not known how the global warming impacts of crop production could be mitigated especially within an agricultural system. The aim of this study is to evaluate possibilities to neutralize global warming impacts in crop production using biochar produced from side flows and buffer zone biomass. A life cycle assessment methodology is utilized in this research for oat production in the boreal climate zone. Global warming impact reductions are compared for three different side flow utilization options. Traditionally, side flows have been utilized in energy or fodder production, and these options are compared to biochar production at a system level. The potential to use buffer zone biomass for biochar production is also studied. Willow has been selected as a biomass source in buffer zones. Oat production leads to greenhouse gas emissions especially due to the use of fossil and mineral fertilizers in cultivation and heat energy, electricity and fuels in various process phases. The production of one metric ton of oat flakes from cradle to gate generates 700 kg of CO 2 eq emissions. Biochar and energy production from side flows enables a greater reduction in global warming impacts than the feed use of side flows. Buffer zones in willow biomass and biochar production may enable the full neutralization of the global warming potential of oat production within an agricultural system. Further research with actual measurements is required especially on biochar impacts on soil emissions such as N 2 O. This research shows that it could be possible to neutralize global warming impacts from crop production using available technologies and available biomass in agricultural systems. A framework is created for carbon neutral crop production using side flows and buffer zone biomass through biochar. • Global warming potential of oat production is studied using LCA methodology. • Oat flakes production generates emissions of 700 kgCO 2eq t−1. • Side flow use for biochar production leads to the lowest overall GWP impacts. • Buffer zone biomass use for biochar production could mitigate the GWP impacts of oat production. [ABSTRACT FROM AUTHOR]

This paper investigates the potential pathways and associated requirements to meet a goal of net-zero greenhouse gas (GHG) emissions from the US commercial aviation sector by 2050 as outlined in the US 2021 Aviation Climate Action Plan. Aviation traffic (RTK) is projected to grow at an average of 2.0% per annum between 2019 and 2050, suggesting that a progressive and ultimately total decoupling of emissions from traffic growth will be required to meet the US aviation sector goal. Aircraft technology advancements, operational efficiency improvements, sustainable aviation fuels, and market-based measures (MBM) are considered as emissions reductions measures towards the goal. A parametric analysis framework is used to develop low, medium, and high emission reduction scenarios for each of these emissions reduction measures. If aircraft technology, operations, and fuels were frozen at 2019 levels, the aviation sector is projected to emit ≈430 million tonnes of CO 2 (MtCO 2) in 2050. Retirements of older aircraft, replaced by current-generation alternatives, may contribute 17% of the total 2050 emissions reduction goal. Further introduction of advanced aircraft technologies may contribute an additional system-level 11% emissions reductions towards the goal. Operational improvements may contribute ≈2% with a range from 1.5 to 4%. The remaining 70% of emissions in 2050 will be addressed through a combination of sustainable fuels and MBM, where appropriate. The level of contribution from fuels will be dependent on continued production ramp-up to meet aviation demand as well as improvements in lifecycle emissions reduction factor (ERF) for current and future fuel feedstock and production pathways, ranging from 0% for current petroleum-based fuels to 100% for sustainable aviation fuels with zero life-cycle emissions. Meeting a net-zero emissions goal by 2050 with SAF would require an increase in SAF production by 57% annually from 2022 to 2030 and 13% per year thereafter, reaching 100% emissions reductions factor by 2050. MBM may fill the gap between residual lifecycle emissions after accounting for all other in-sector improvement opportunities and the goal. [ABSTRACT FROM AUTHOR]

Food systems contribute 23–42% of global greenhouse gas emissions. Reducing food system emissions is an essential component of climate change mitigation, and a system-wide approach, including production, processing, trade and demand-side transformations, will be needed. Long-term analysis of greenhouse gas (GHG) emissions of food supply is crucial for informing this transformation, and understanding the processes contributing to existing trends can reveal opportunities for future mitigation strategies. To address these needs we used data on food supply, trade and emission intensity to quantify changes in GHG emissions between 1986 and 2017 resulting from food supply in the United Kingdom (UK). Uniquely, the relative contributions of supply-side and demand-side changes to historical trends in food emissions were assessed, and the gap between current UK food consumption and EAT-Lancet recommended diets was used to estimate the additional GHG emission reductions that could be achieved by shifting to the Planetary Health Diet (PHD). It was estimated that in the UK, per-capita GHG emissions from food fell by 32% (from 4.6 tCO 2 eq/capita to 3.1 tCO 2 eq/capita) between 1986 and 2017. Of this 32% reduction, 21% was due to supply-side changes (a fall in emission intensity per unit of production due to increased efficiency of farming practices), 10% was due to demand-side changes (including dietary change and waste reduction), and 2% was due to changing trade patterns. Relative to the PHD, however, the average UK citizen still greatly over-consumes beef, lamb and pork, tubers and starchy vegetables and dairy products, and under-consumes vegetables, nuts, and legumes. It was estimated that by adopting the PHD, UK per capita food emissions could be reduced by a further 42% to 1.8 tCO 2 eq/capita. These results expose the historic contributions of both supply- and demand-side changes to reductions in GHG emissions from food, and highlight the underutilised potential of dietary change in contributing to mitigation of GHG emissions from food. [Display omitted] • UK per-capita food emissions fell by 32% between 1986 and 2017. • Supply and demand-side changes contributed to this reduction. • Adopting the Planetary Health Diet could reduce emissions of UK food supply by 42%. • This reveals the underutilised potential of dietary change as a mitigation strategy. [ABSTRACT FROM AUTHOR]

India has a significant importance in achieving the global Paris agreement's long-term goal as it is the world's third-largest consumer of energy. This paper aims to improve the understanding of the opportunities and constraints of decarbonizing India's electricity sector and adds to the growing body of literature by modelling the electricity sector in India with a dynamic optimization approach that assesses options for effective greenhouse reductions through carbon pricing. Attaining significant variable renewable energy penetration in India by 2050 is consistent with the lowest cost power generation options identified through our simulations, where solar and wind can provide 66 % of the electricity needs by 2050, even without a carbon price. With a carbon price of US$50/tCO2e, the simulations project that wind and power generation share in the electricity mix will rise to 81 %, leading to significant emission reductions. In this scenario, power sector emissions will be 164 million tCO2e by 2050, which is only about 14 % of the emissions levels in 2019. The analysis also indicates that fossil fuels remain part of India's electricity mix in 2050, but their role and operation would dramatically change. When a carbon price of US$50/tCO2e is introduced, coal capacity remains valuable to fill demand when solar and wind are not available. This would require modifications in operation schedules and repurposing coal power plants for frequent ramping up and down. [ABSTRACT FROM AUTHOR]

Abstract Land-use changes can alter soil carbon (C) contents, and in particular deforestation has been responsible for a large part of the cumulative human-induced greenhouse gas (GHG) emissions. This study aimed to determine the influence of land-use and land cover change on soil organic carbon (SOC) content, microbial biomass C (MBC) and microbial respiration (MR) in the Hyrcanian forests, north of Iran. We compared an agricultural field (AF), plantations of Alnus subcordata (AS), Acer velutinum (AV), Quercus castaneifolia (QC) and Cupressus sempervirens (CS), and a natural forest (NF). Soil samples were collected at three different depths (0–20, 20–40 and 40–60 cm). Results showed that different land covers significantly affected soil characteristics, and SOC increased by 25% and 1.11% after the conversion of NF to CS and AS plantations respectively, and decreased by 4%, 12.11% and 53% when NF was converted to QC, AV and AF respectively. In all treatments, MBC and MR were significantly higher (p < 0.05) in the 0–20 cm depth, and MR was also correlated positively with MBC and SOC. Microbial biomass was near the half in the agriculture field than in plantations and natural forest in the upper layer, but the effects of land use on microbial biomass C decreased with soil depth. However, we observed considerable amounts microbial biomass C in 40–60 cm depth. Also, results showed that topographical feature, altitude and slope, will affect SOC content. Our results indicated that forest plantation is a key measure to enhance SOC content and mitigate global CO 2 emission, especially when soils are degraded and have low soil C content. In particular, afforestation had a crucial effect on elevating SOC content in the Hyrcanian forest, but plantations of oak (QC) and maple (AV) were less effective in terms of soil C increase. Graphical abstract Unlabelled Image Highlights • SOC increased after the conversion of NF to CS and AS plantations. • SOC stock of the agricultural field was about 50% lower compared to the NF. • Half of SOC content in agriculture field is concentrated in 0–20 cm of soil. • MBC decrease with depth, but there was a considerable MBC in the 40–60 cm depth. • The effects of land use on microbial biomass C decrease with depth. [ABSTRACT FROM AUTHOR]

Abstract Biochar-based carbon management networks (CMNs) offer a means of achieving negative net greenhouse gas (GHG) emissions. Such systems rely on relatively mature technologies for biochar production, distribution and application by tillage; thus, the prospects for near-term scale-up, especially in developing countries with agriculture-intensive economies, are promising. The main technological gap lies in the capability to predict, optimize and monitor the actual climate change mitigation benefits. Computer-aided planning of biochar-based CMNs will be needed to maximize GHG reductions while minimizing any potential adverse environmental impacts. Such models can help decision-makers to understand and optimize the cost/benefit aspects of such systems to accelerate their commercial deployment. This paper gives a brief review of the available scientific literature, and discusses prospective areas for further research to facilitate the large-scale use of biochar as a negative emissions technology (NET). Highlights • Biochar application to soil is a potentially scalable negative emissions technology. • Biochar-based carbon management networks can be operated based on this concept. • Computer-aided planning, optimization and monitoring are required. • An integrated modelling framework should be developed for effective decision support. [ABSTRACT FROM AUTHOR]

Abstract This study reviews conservative political party policy positions in six European countries with high greenhouse-gas emissions (France, Germany, the Netherlands, Poland, Spain, and the U.K.). Using party platform statements from recent election campaigns, the positions of moderate conservative parties are compared with those of far-right political parties to investigate similarities and differences on energy-transition policy. Three areas of policy are considered: climate-change mitigation, fossil-fuel development or sunsetting, and renewable energy and energy efficiency development. In the countries examined, moderate conservative parties generally remain committed to climate-mitigation policy and renewable energy and energy efficiency policy, but there are some roll-backs of support, and there is variation in their support for fossil-fuel development. Far-right parties tend to show evidence of rejection of climate science, opposition to decarbonization in general, support for natural gas hydraulic fracturing technologies, support for continued use of coal, and opposition to some types of policy favorable to renewable energy and energy efficiency. However, some far-right parties, notably in France and Spain, share several important positions with the center-right parties. The study cautions against assuming an automatic linkage between far-right parties and opposition to energy-transition policies and against assuming that far-right parties will oppose all types of energy-transition policies. Highlights • Skepticism and rejection of climate science appears in some of the platforms of far-right Euroskeptic parties. • The far-right parties of Germany, the Netherlands, and the U.K. are strongly opposed to a range of energy-transition policies. • The far-right parties of France and Spain have more moderate positions that are close to center-right parties. • Far-right parties tend to be opposed to wind power but less so to energy efficiency and distributed solar. [ABSTRACT FROM AUTHOR]

Abstract The Canadian province of Quebec has set for 2030 a greenhouse gas (GHG) emission reduction target of 37.5% below 1990 levels. Meeting such a reduction target requires in particular a rapid transition to a low-carbon energy system. This paper proposes prospective energy scenarios for Quebec up to 2030, under different GHG emission reduction constraints (up to a 40% reduction). The main objective is to explore the role of bioenergy in achieving the reduction targets. Our analysis is based on the North American TIMES Energy Model (NATEM). It belongs to the MARKAL/TIMES family of models supported by the International Energy Agency, and includes a detailed bioenergy sector. Compared to the reference case (baseline), our results indicate a larger share of bioenergy in 2030 (up to a threefold increase in the most stringent GHG reduction scenario), with up to a fourfold increase in the total amount of feedstock used for bioenergy production. Our study envisions thus a much larger penetration of bioenergy than the one proposed by the government of Quebec in its 2030 Energy Policy. Highlights • Prospective energy scenarios for the Province of Quebec under GHG reduction targets. • Use of a TIMES optimization energy model to derive socially optimal solutions. • Explore the role of bioenergy in achieving the reduction targets. • Results indicate a larger penetration of bioenergy than the one proposed by the government of Quebec in its 2030 Energy Policy. [ABSTRACT FROM AUTHOR]

Abstract The rapid global growth in the use of renewable energy to reduce GHG emissions and mitigate climate change, through the inclusion of large amounts of PV and wind in existing electricity grids, has highlighted certain challenges. Most critically, their intermittent supply, necessitates flexible dispatchability from other generators in the grid. Currently, few renewable energy technologies offer this dispatchability, with only concentrating solar power (CSP) offering storage. CSP generates electricity from thermal heat, similar to fossil-driven thermal power plants, with the heat-source being inexhaustible concentrated solar irradiance. The thermal process, however, requires cooling, best achieved with a finite resource; water. CSP is ideally suited to areas of high solar irradiation, typically arid and water stressed. The need for water as a source of cooling is often neglected in the planning and development of CSP. This paper identifies water as a constraint to CSP deployment, and explores CSP's potential contribution to generation through the lens of the water-energy nexus. This aids our understanding of how water availability threatens expected CSP production capacity and places natural limits on its sustainable development. For strategic planning of CSP, we therefore propose the inclusion of integrated water resource management in CSP energy infrastructure planning. Highlights • Identify and explain the dependence of CSP on water as a limited resource. • Highlight disparity between co-location of high DNI and lack of water resources. • Highlight impact of variability of water resources on existing thermal power plants. • Identify lack of water resource consideration in CSP deployment planning. • Suggested integration of water resource management into CSP deployment planning. [ABSTRACT FROM AUTHOR]

Abstract Forest-based bioenergy plays an important role in climate mitigation for limiting global mean temperature increase to below 2 °C. The greenhouse gas (GHG) impact of three forest-based bioenergy systems from the USA, Canada and Spain supplying wood pellets for electricity in the UK were evaluated by conducting lifecycle assessments and forest carbon modelling of the three forest systems. Cumulative emissions were analysed by calculating the forest carbon stock change and net GHG emissions balance of the forest-based bioenergy electricity. The analysis considered both the replacement of the existing electricity mix with bioenergy electricity and forest management with and without bioenergy use. The supply chain emissions and forest carbon balances indicated that GHG emission reductions are possible. However, the cumulative net GHG balance at forest landscape scale revealed that the reduction potential is limited, potentially with no GHG reductions in fast growing forests with shorter rotations, while slow growing forest systems with longer rotations result in greater GHG reductions. This means that the maximum climate benefit is delivered at a different point in time for different forest systems. To evaluate the climate change mitigation potential of forest-based bioenergy it is therefore necessary to consider the management, utilisation and relevant counterfactual of the whole forest and its products. In terms of climate change mitigation potential and minimising possible negative impacts that would require multi-level governance. Highlights • Net GHG balance shows GHG reduction potential of forest bioenergy is limited. • Results are dependent on methods, system boundaries and reference system. • Mitigation potential depends on forest management and whole forest product basket. • Multi-level governance framework require to track wider impacts of forest bioenergy. [ABSTRACT FROM AUTHOR]

Abstract Japan is the sixth largest greenhouse gas emitter in 2016 and plays an important role to attain the long-term climate goals of the Paris Agreement. One of the key policy issues in Japan's energy and environmental policy arena is the energy system transition to achieve 80% emissions reduction in 2050, a current policy goal set in 2016. To contribute to the ongoing policy debate, this paper focuses on energy-related CO 2 emissions and analyzes such decarbonization scenarios that are consistent with the government goals. We employ six energy-economic and integrated assessment models to reveal decarbonization challenges in the energy system. The modeling results show that Japan's mitigation scenarios are characterized by high marginal costs of abatement. They also suggest that the industrial sector is likely to have a large final energy share and significant residual emissions under the 80% reduction scenario, though it is generally thought that the transport sector would have large decarbonization challenges. The present findings imply that not only energy policy but also industrial policy may be relevant to the long-term environmental target. Given the high marginal costs exceeding those of negative emissions technologies that could place a cost ceiling, further model development would be crucial. Highlights • We analyze the energy system scenarios to achieve 80% reduction in carbon dioxide emissions by 2050. • We employ six integrated assessment models to reveal decarbonization challenges in the energy system. • The model results show that the industrial sector has a large final energy share and significant residual carbon dioxide emissions under the 80% reduction scenario. • We also show that Japan's mitigation scenarios are accompanied with high marginal costs of abatement. [ABSTRACT FROM AUTHOR]

Abstract Cities, the core of the global climate change mitigation and strategic low-carbon development, are shelters to more than half of the world population and responsible for three quarters of global energy consumption and greenhouse gas (GHG). This special volume (SV) provides a platform that promotes multi- and inter- disciplinary analyses and discussions on the climate change mitigation for cities. All papers are divided into four themes, including GHG emission inventory and accounting, climate change and urban sectors, climate change and sustainable development, and strategies and mitigation action plans. First, this SV provides methods for constructing emission inventory from both production and consumption perspectives. These methods are useful to improve the comprehensiveness and accuracy of carbon accounting for international cities. Second, the climate change affects urban sectors from various aspects; simultaneously, GHG emissions caused by activities in urban sectors affect the climate system. This SV focuses on mitigation policies and assessment of energy, transport, construction, and service sectors. Third, climate change mitigation of cities is closely connected to urban sustainable development. This SV explores the relationships between climate change mitigation with urbanization, ecosystems, air pollution, and extreme events. Fourth, climate change mitigation policies can be divided into two categories: quantity-based mechanism (e.g., carbon emission trading) and price-based mechanism (e.g., carbon tax). This SV provides experiences of local climate change mitigation all over the world and proposes the city-to-city cooperation on climate change mitigation. [ABSTRACT FROM AUTHOR]

Abstract The Paris Agreement brings countries together in a combined effort to combat climate change and its effects. A key target is the reduction of energy related greenhouse gas emissions. Providing biogas from biomass is one option to provide renewable and less carbon intensive fuels. When upgraded to biomethane it may be a substitute for natural gas and thus may have many application pathways. Recognising this potential many European countries installed governmental support programmes to stimulate market growth over the last decade. However, most of the installed schemes in Europe are time-limited. Besides being time-limited most of the schemes include a degression of compensation over time, resulting in many having limited success over longer time frames. This study questions the feasibility of near-term business cases for biomethane plants and analyses options for making them less dependent on governmental support programmes. Currently a market potential is seen in the utilization of process carbon dioxide in carbon capture and utilization or carbon capture and storage pathways, because it is a widely available side product from biogas upgrading. Therefore, we examined three business cases for its utilization in across sectors. To answer the research question we use a previously developed biomethane market simulation model and added an extension for new business cases. Results indicate that there are specific business options in the field of 2160 m³ h−1 to 20,840 m³ h−1 that are economical feasible under certain circumstances. Highlights • Use of CO2 in the chemical industry was not economically feasible even under optimistic conditions. • Utilization of carbon dioxide from biogas upgrading offers new business options. • Production of bio-LNG is a promising business option. [ABSTRACT FROM AUTHOR]

Abstract Failures of countries to set and achieve renewable energy targets are prevalent, producing uncertainty as to the possibility of renewable energy contributing to a reduction in global emissions. Lack of policy and incorrect modelling analyses are among the sources of these failures and understanding these two sources is crucial for improving confidence in renewables. We assess errors in projections pertaining to the capacity and production of renewable energy in the United States and those countries of the European Union that have strong commitments to green energy supply. Our results show that solar energy has the lowest level of uncertainty as it has the most achievable capacity projections. However, other renewables entail more attractive policies and further research is needed for the advancement of reliable technology and accurate weather predictions. Our findings also provide ranges for the projection uncertainties for six renewable energy technologies, drawing attentions to ways that the dominant errors in these renewable energy projections may be rectified. Highlights • Projection errors of capacity and production of six renewable energy technologies in the US and EU countries are estimated. • Solar energy target is the most achievable. • Achieving capacity target does not guarantee to achieve production target. [ABSTRACT FROM AUTHOR]

Highlights • The present study explored community-action-oriented projects on litter management. • The study adopted a mixed method of data collection. • Data were collected through: questionnaire and a life-cycle-based model. • Respondents' knowledge scores before and after the intervention were significantly different. • All (100%) the participants were willing to participate in waste recycling business. • 4Rs strategy had potential in saving greenhouse gas emissions in the community. Abstract Throughout the world, waste sector has been implicated in significant contribution to anthropogenic greenhouse gas (GHG) emissions. Involving communities in recycling their solid waste would ensure climate change effect mitigation and resilience. This study was carried out to improve waste management practices through a community-led intervention at Kube-Atenda community in Ibadan, Nigeria. The study adopted a quasi-experimental design, comprising mixed method of data collection such as semi- structured questionnaire and a life-cycle-based model for calculating greenhouse gas generation potentials of various waste management practices in the area. A systematic random sampling was used to select sixty (60) households for a survey on knowledge, attitude and practices of waste management through Recovery, Reduction, Reuse and Recycling (4Rs) before and after the training intervention. Data collected were summarised using descriptive statistics, chi-square test, t -test and ANOVA at p = 0.05. The mean age of the respondent was 49.7 ± 16.7 and 68.3% were females. Respondents' knowledge scores before and after the intervention were significantly different: 7.07 ± 1.48 and 11.6 ± 1.6 while attitude scores were: 8.2 ± 2.3 and 13.5 ± 0.8. There were significant differences in the major waste disposal practices in the community before and after the intervention. All (100%) the participants were willing to participate in waste recycling business and the model predicted that adoption of 4Rs strategy had a great potential in saving greenhouse gas emissions in the community. The behaviour of the community people has changed towards waste management that promote climate change mitigation and adaptation through waste reduction, reuse, and resource recovery. [ABSTRACT FROM AUTHOR]

Sub-national and regional greenhouse gas (GHG) mitigation policies are being stimulated by the Paris Agreement. Several low carbon studies have been conducted for important emitters such as California State in the US and Chinese provinces. At the same time, carbon mitigation studies have focused on the industrial sector, especially in developing countries. In comparison to the national scenario, the Sao Paulo state in Brazil shows a distinct emission profile. The industry in Sao Paulo is responsible for 14.7% of the total emissions, and this share increases to 31.5% considering energy indirect emissions. Therefore, Sao Paulo mitigation efforts depend on industry’s leadership such as in other parts of the world. The present study has evaluated the Sao Paulo state’s industry mitigation potential between 2014 and 2030 based on a Marginal Abatement Cost (MAC) curve. In contrast to previous MAC studies, the MAC-SP study has also considered cement related emissions released outside its jurisdictions but that are driven by industrial choices within its boundary. Nine out of seventeen technologies show a negative MAC value, and energy efficiency technologies yield the lowest cost with a weighted average value of -$122/metric ton of CO 2 . Considering only the territorial based approach, the Sao Paulo state’s Industry would avoid 78.4 million metric ton of CO 2 until 2030. Although emissions under Sao Paulo’s responsibility increase 27%, if the consumption-based approach is adopted, the assessed mitigation potential enhances 83% and entails US$ 2.3 billion savings until 2030. In conclusion, the mitigation potential for São Paulo state’s industry is sizeable and consumption-based strategies are worthwhile, especially when regional policies are considered. Results can assist in formulating climate change policies and innovative incentive mechanisms to maximize the regional mitigation potential. [ABSTRACT FROM AUTHOR]

Global firms are increasingly adopting greenhouse gas mitigation targets in response to climate change. These targets serve as a spur for carbon mitigation initiatives, provide guidelines to select appropriate mitigation actions, and set the standards to measure the progress of the mitigation efforts. Despite their important functionalities, firm-level mitigation targets have rarely been studied. In this paper we aim to provide a comparative view on mitigation targets set by global firms across different countries and industrial sectors. The analysis focuses on four dimensions, i.e., adoption, metric, scope, and stringency. We find Japan far leads the other major countries in terms of target adoption, but the targets of Japanese firms are generally less stringent. Canadian firms are laggards in both target adoption and target stringency. The mitigation targets are also considerably uncommon among Australian firms. Firms in developing countries fall behind in target stringency and display a significantly greater divergence than developed countries in sectoral adoption rate. The European Union firms are most likely to cover the emissions in their supply chains in targets. Target stringency has substantially tightened from 2005 to 2012. For all the countries in this study, around 95% of the firm-level targets are more stringent than the Intended Nationally Determined Contributions submitted to the Paris Agreement. Setting mitigation target has a significant positive impact on both the likelihood of investing in renewable energy and the amount of investment in renewable energy. However, there is no evidence that more stringent targets lead to higher investment. These findings point to the most pressing issues with regard to corporate mitigation target-setting that policymakers and corporate management should address. [ABSTRACT FROM AUTHOR]

Abstract Climate change mitigation involves reducing fossil fuel consumption and greenhouse gas emissions, which is expensive, particularly under stringent mitigation targets. The co-benefits of reducing air pollutants and improving human health are often ignored, but can play significant roles in decision-making. In this study, we quantified the co-benefits of climate change mitigation on ambient air quality and human health in both physical and monetary terms with a particular focus on Asia, where air quality will likely be degraded in the next few decades if mitigation measures are not undertaken. We used an integrated assessment framework that incorporated economic, air chemistry transport, and health assessment models. Air pollution reduction through climate change mitigation under the 2 °C goal could reduce premature deaths in Asia by 0.79 million (95% confidence interval: 0.75–1.8 million) by 2050. This co-benefit is equivalent to a life value savings of approximately 2.8 trillion United States dollars (USD) (6% of the gross domestic product [GDP]), which is decidedly more than the climate mitigation cost (840 billion USD, 2% of GDP). At the national level, India has the highest potential net benefit of 1.4 trillion USD, followed by China (330 billion USD) and Japan (68 billion USD). Furthermore, in most Asian countries, per capita GDP gain and life value savings would increase with per capita GDP increasing. We robustly confirmed this qualitative conclusion under several socioeconomic and exposure-response function assumptions. Highlights • We quantified the co-benefits of climate mitigation on air quality and human health in Asia. • We used integrated assessment framework with economic, air quality and health assessment models. • Climate target of 2 °C could reduce premature deaths in Asia by 0.79 million by 2050. • The monetary co-benefit is 6% of the gross domestic product and exceeds the climate mitigation cost (2% of GDP). • India has the highest net benefit (1.4 trillion USD), followed by China (330 billion USD) and Japan (68 billion USD). [ABSTRACT FROM AUTHOR]

Biochar production for soil amendment was recently proposed as a tool to mitigate climate change, reducing soil greenhouse gas (GHG) emissions and sequestrating carbon (C) in soil. The aim of this research project was to test the hypothesis that only biochars with specific requirements (low H/C org and O/C org ratios, high C/N ratio) can reduce soil N 2 O emissions without increasing CO 2 emissions in the short term. A 45-days incubation study was carried out, in which six engineered biochars made from the pyrolysis of wood, switchgrass and the solid fraction of pig manure (SFPM), were amended to two agricultural soils (loamy sand and silt loam) at a dose of 2% (w/w) in 1-liter jars. Soil moisture content was adjusted at 80% of water-filled pore space with a solution of ammonium nitrate that corresponds to 170 kg of nitrogen per hectare. N 2 O and CO 2 emissions were analysed on days 2, 3, and then weekly. Soil chemical properties and bacterial richness, composition and taxonomy were analysed after the incubation period. When compared to the control soils without biochar, N 2 O emissions were decreased by 42 to 90%, but only in the silt loam amended with biochars made from wood and switchgrass, these biochars having a high C/N ratio (>30). Lower N-NH 4 + and N-NO 3 − concentrations were observed in these biochar treatments than in control soil. Moreover, two bacterial classes ( Deltaproteobacteria and Thermoleophilia ) were correlated with a decrease in N 2 O emissions. For each type of biochar, those produced at the highest temperature with low O/C org and H/C org ratios resulted in the lowest increase in CO 2 emissions, which could indicate a higher biochar carbon stability. Overall, results of this study demonstrated that biochar can either increase or decrease soil GHG emissions depending on its properties, and that the effect can differ according to soil properties. Future long-term studies in the field in the presence of crop should be carried out in order to validate the conclusions of this study. [ABSTRACT FROM AUTHOR]

Petroleum coke, a non-environmentally friendly energy source, is gradually replacing other power fuels in China’s industrial enterprises because of its price advantage. Petroleum coke has high emission factors and thus emits more greenhouse gases (GHGs) and air pollutants than even raw coal. This study first examines the rapid growth of petroleum coke consumption in China since 2010 by industry sector and region and then estimates the petroleum coke-related emissions. We conclude that the total consumption of petroleum coke increased by 18.9% from 2010 to 2016 and that the industry final consumption for burning in boilers increased dramatically (by 158.2%). Petroleum coke-related CO 2 emissions reached 28 million tonnes in 2016, whereas CH 4 and N 2 O emissions totaled 870 and 143 tonnes, respectively. The increased use of petroleum coke will increase the urgency for the development of climate change mitigation and emissions reduction measures in China. We propose several possible policy suggestions for petroleum coke management and emissions control, such as strongly restricting the production and import of high-sulphur petroleum coke, as well as burning petroleum coke to provide power; more power plants and industrial kiln stoves/boilers should be equipped with efficient decontamination systems; the development of advanced industrial processes and the clean utilization of petroleum coke should be encouraged. [ABSTRACT FROM AUTHOR]

Climate change and increased electrification of space and water heating in buildings can significantly affect future electricity demand and hourly demand profiles, which has implications for electric grid greenhouse gas emissions and capacity requirements. We use EnergyPlus to quantify building energy demand under historical and under several climate change projections of 32 kinds of building prototypes in 16 different climate zones of California and imposed these impacts on a year 2050 electric grid configuration by simulation in the Holistic Grid Resource Integration and Deployment (HIGRID) model. We find that climate change only prompted modest increases in grid resource capacity and negligible difference in greenhouse gas emissions since the additional electric load generally occurred during times with available renewable generation. Heating electrification, however, prompted a 30–40% reduction in greenhouse gas emissions but required significant grid resource capacity increases, due to the higher magnitude of load increases and lack of readily available renewable generation during the times when electrified heating loads occurred. Overall, this study translates climate change and electrification impacts to system-wide endpoint impacts on future electric grid configurations and highlights the complexities associated with translating building-level impacts to electric system-wide impacts. [ABSTRACT FROM AUTHOR]

Maritime emission regulations set limits for SOx and NOx emissions for health and environmental reasons, and for CO 2, through the Energy Efficiency Design Index (EEDI), with the general aim of mitigating global warming. EEDI verification is performed at the vessel's design speed and design loads, under calm-water conditions. This, although calm seas are the exception in shipping, and that even with calm-water conditions, ships usually operate at lower speeds than their design speed. A major challenge, if greenhouse gases (GHG) reduction targets are to be met through the EEDI, will be to identify EEDI-compliant solutions that reduce energy consumption and GHG emissions under realistic operational conditions, from lying idle at berth in port to when full power is required in critical situations at sea. In view of all the above, we use the Aframax tanker class to illustrate how such an assessment can be performed, and to display the differences in costs and benefits of options, all of which meet the requirements of the EEDI. [ABSTRACT FROM AUTHOR]