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To achieve carbon neutrality in China’s fossil energy sector, saline aquifer CO₂ geological storage has become a critical strategy. As research into carbon reduction and storage potential evaluation advances across various geological scales, the need arises for consolidating key CO₂ storage cases and establishing a standardized classification system and evaluation methodology. This paper provides a comprehensive review of notable CO₂ storage projects in saline aquifers, covering aspects such as project overviews, structural and reservoir characteristics, caprock integrity, and seismic monitoring protocols. Drawing on insights from mineral and oil and gas exploration, as well as international methods, this paper outlines the stages and potential levels of saline aquifer storage in China. It proposes an evaluation framework with formulas and reference values for key coefficients. The study includes successful global projects, such as Sleipner and Snøhvit in Norway, In Salah in Algeria, and Shenhua in China’s Ordos Basin, which provide valuable insights for long-term carbon capture and storage (CCS). By examining geological characteristics, injection, and monitoring protocols in these projects, this paper analyzes how geological features impact CO₂ storage outcomes. For example, the Sleipner project’s success is linked to its straightforward structure, favorable reservoir properties, and stable caprock, while Snøhvit illustrates diverse structural suitability, and In Salah demonstrates the influence of fractures on storage efficacy. CO₂ storage activities are segmented into four stages—survey, investigation, exploration, and injection—and are further categorized by storage potential: geological, technical, techno-economic, and engineering capacities. This study also presents evaluation levels (prediction, control, technically recoverable, and engineering) that support effective reservoir selection, potential classification, and calculations considering factors like reservoir stability and sealing efficacy. Depending on application needs, volumetric or mechanistic methods are recommended, with precise determination of geological, displacement, and cost coefficients. For China, a dynamic evaluation mechanism characterized by multi-scale, tiered approaches and increasing precision over time is essential for robust storage potential assessment. The levels and methods outlined here serve as a scientific foundation for regional and stage-based comparisons, guiding engineering approvals and underground space management. To align with practical engineering demands, ongoing innovation through laboratory experiments, simulations, and field practice is crucial, supporting continual refinement of formulas and key parameter determinations. Full article

Currently, the UK has ambitious plans to reach net zero by 2050, despite other countries such as Russia and India targeting 2060 and 2070, respectively. Assuming that the UK emissions unceasingly decline at a given rate annually towards achieving net zero by 2050, its economy would need to ensure a reduction of 105 MtCO2 per year of its emissions from the current 2021 levels. Given that global greenhouse gas emissions have not peaked and continue to rise, the UK seeks to implement costly and aggressive emission reduction policies towards fulfilling commitments under the 2021 Glasgow Climate Pact. This paper investigates the effect of environmental taxes on environmental degradation in the UK between 2000Q1 and 2019Q4 using novel Fourier approaches. Using the novel Fourier ARDL estimator, the long-run equilibrium estimates indicate that gross domestic product and environmental tax cause a fall in carbon emissions. However, in trade and primary energy use, a unit change caused rising carbon emissions in the UK. Especially, the results indicate that environmental taxes have a negative effect on environmental degradation in the UK, and ecological tax policy could be considered as an effective channel to attain environmental sustainability. The outcome provides the following policy insights: (i) The government of the UK should support international environmental tax coordination mechanisms, especially on carbon pricing, to avoid relocation of carbon-intensive investments. (ii) The UK government must note that imposing more taxes to encourage emissions reductions could bring complexity to the tax system and unnecessarily bring costly ways to deal with climate change. Higher domestic electricity prices could disproportionately hit low-income households and create distributional cost concerns, which require benefit payouts or compensation schemes. (iii) Switching to electric vehicles simultaneously requires investments in charging infrastructure and battery technologies. To avoid this chicken-and-egg problem, the government of the UK could play a coordinating role, including deploying targeted subsidies, regulations, direct government involvement, or setting higher carbon prices in special cases. Full article

Solar energy plays a crucial role in mitigating greenhouse gas emissions in the context of global climate change. However, its deployment for green electricity generation can significantly influence regional climate and vegetation dynamics. While prior studies have examined the impacts of solar power plants on vegetation, the accuracy of these assessments has often been constrained by the availability of publicly accessible multispectral, high-resolution remotely sensed imagery. Given the abundant solar energy resources and the ecological significance of the Tibetan Plateau, a thorough evaluation of the vegetation effects associated with solar power installations is warranted. In this study, we utilize sub-meter resolution imagery from the GF-2 satellite to reconstruct the fractional vegetation cover (FVC) at the Gonghe solar thermal power plant through image classification, in situ sampling, and sliding window techniques. We then quantify the plant’s impact on FVC by comparing data from the pre-installation and post-installation periods. Our findings indicate that the Gonghe solar thermal power plant is associated with a 0.02 increase in FVC compared to a surrounding control region (p < 0.05), representing a 12.5% increase relative to the pre-installation period. Notably, the enhancement in FVC is more pronounced in the outer ring areas than near the central tower. The observed enhancement in vegetation growth at the Gonghe plant suggests potential ecological and carbon storage benefits resulting from solar power plant establishment on the Tibetan Plateau. These findings underscore the necessity of evaluating the climate and ecological impacts of renewable energy facilities during the planning and design phases to ensure a harmonious balance between clean energy development and local ecological integrity. Full article

The global rise in population and advancement in civilization have led to a substantial increase in energy demand, particularly in the industrial sector. This sector accounts for a considerable proportion of total energy consumption, with approximately three-quarters of its energy consumption being used for heat processes. To meet the Paris Agreement goals, countries are aligning policies with international agreements, and companies are setting net-zero targets. Upstream emissions of the Scope 3 category refer to activities in the company’s supply chain, being crucial for achieving its net-zero ambitions. This study analyzes heating solutions for the supply chain of certain globally operating companies, contributing to their 2030 carbon-neutral ambition. The objective is to identify current and emerging heating solutions from carbon dioxide equivalent (CO₂e) impact, economic, and technical perspectives, considering regional aspects. The methodology includes qualitative and quantitative surveys to identify heating solutions and gather regional CO₂e emission factors and energy prices. Calculations estimate the CO₂e emissions and energy costs for each technology or fuel, considering each solution’s efficiency. The study focuses on Europe, the United States, Brazil, China, and Saudi Arabia, regions or countries representative of companies’ global supply chain setups. Results indicate that heat pumps are the optimal solution for low temperatures, while biomass is the second most prevalent solution, except in Saudi Arabia where natural gas is more feasible. For medium and high temperatures, natural gas is viable in the short term for Saudi Arabia and China, while biomass and electrification are beneficial for other regions. The proportion of electricity in the energy mix is expected to increase, but achieving decarbonization targets requires cleaner energy mixes or competitive Power Purchase Agreement (PPA) projects. Brazil, with its high proportion of renewable energy sources, offers favorable conditions for using green electricity to reduce emissions. The utilization of biomethane is promising if costs and incentives align with those in the EU. Although not the objective of this study, a comprehensive analysis of CAPEX and lifecycle costs associated with equipment is necessary when migrating technologies. Policies and economic incentives can also make these solutions more or less favorable. Full article

Catalytic methane decomposition (CMD) reaction is considered a promising process for converting greenhouse gas CH₄ into hydrogen and high-value-added carbon materials. In this work, a series of Al₂O₃-supported FeCo alloy catalysts were successfully prepared in the CMD process. Compared to the pre-reduced catalysts, the in situ reduced FeCo alloy catalysts showed higher methane conversion rates, with the highest reaching 83% at 700 °C, due to the finer active nanoparticle size and greater exposure of active site. Furthermore, the time-on-stream tests demonstrated that the catalytic activity of in situ reduced FeCo alloy catalysts could remain above 92.3% of the highest catalytic activity after 10 h. In addition, TEM analyses of the carbon products from the CMD in situ reduced catalysts revealed the production of carbon nanofibers and nanotubes several microns in length after the reaction. This indicates that the in situ reduced FeCo alloy catalysts more effectively promoted the growth of carbon nanofibers. These results could provide a viable strategy for future methane decomposition development aimed at producing hydrogen and high-value carbon. Full article

Gravel mulching is a widely employed strategy for water conservation in arid agricultural regions, with potential implications for soil carbon (C) sequestration and greenhouse gas emissions. However, soil respiration and CO₂-C emissions remain uncertain owing to less consideration of the influence of precipitation patterns and planting age. In this study, we investigated the soil respiration rate (R_soil) and cumulative CO₂-C emission (C_cum), both measured over a period of 72 h, along with soil properties and enzyme activities under different precipitation conditions based on gravel mulching with different planting ages. We analyzed the effects of planting ages on R_soil and C_cum and revealed the underlying mechanisms driving changes in environmental factors on R_soil and C_cum. The results demonstrated that the R_soil reached the maximum value at about 1 h, 0.5 h, and 0.25 h after rewetting in 1, 10, and 20 years of gravel mulching under the condition with 1 mm, 5 mm, and 10 mm of precipitation, respectively, whereas the R_soil exhibited its maximum at about 8 h after soil rewetting under precipitation of 30 mm. The C_cum induced by precipitation pulses tends to decrease with increasing years of gravel mulching. The C_cum was 0.0061 t ha⁻¹ in the 20-year gravel-mulched soil, representing a 53.79% reduction compared to the 1-year gravel-mulched soil. Soil organic matter (SOM), planting ages, and alkaline phosphatase (ALP) were the primary factors influencing the R_soil and C_cum in 0–20 cm, while SOM, planting ages, and soil porosity (AirP) were the key factors affecting the R_soil and C_cum in 20–40 cm. The R_soil and C_cum in the 0–20 cm soil were regulated by soil enzyme activities, while those of 20–40 cm soil were controlled by soil properties. This indicates that the decrease in R_soil and C_cum is caused by soil degradation, characterized by a decrease in SOM and ALP. This study offers a novel insight into the long-term environmental impact of gravel mulching measures in arid areas, which is helpful in providing a theoretical basis for dryland agricultural management. It is imperative to consider the duration of gravel mulching when predicting the potential for C sequestration in arid agricultural areas. Full article

Mitigation of greenhouse gases (GHGs), improving nutrient-use efficiency (NUE), and maximizing yield in rainfed lowland rice cultivation poses significant challenges. To address this, a two-year field experiment (2020 and 2021) was conducted in Assam, India, to examine the impact of different fertilizer-management practices on grain yield, NUE, and GHGs in wet direct-seeded rice (Wet-DSR) during the kharif season. The experiment included eight treatments: control; farmer’s practice (30-18.4-36 kg N-P₂O₅-K₂O ha⁻¹); state recommended dose of fertilizer (RDF) @ 60-20-40 kg N-P₂O₅-K₂O ha⁻¹ with N applied in three splits @ 30-15-15 kg ha⁻¹ as basal, at active tillering (AT), and panicle initiation (PI); best fertilizer management practices (BMPs): 60-20-40 kg N-P₂O₅-K₂O ha⁻¹ with N applied in three equal splits as basal, at AT, and PI; and fertilizer deep placement (FDP) of 120%, 100%, 80%, and 60% N combined with 100% PK of RDF. The experiment was arranged out in a randomized complete block design with three replications for each treatment. The highest grain yield (4933 kg ha⁻¹) and straw yield (6520 kg ha⁻¹) were achieved with the deep placement of 120% N + 100% PK of RDF. FDP with 80% N + 100% PK reduced 38% N₂O emissions compared to AAU’s RDF and BMPs, where fertilizer was broadcasted. This is mainly due to the lower dose of nitrogen fertilizer and the application of fertilizer in a reduced zone of soil. When considering both productivity and environmental impact, applying 80% N with 100% PK through FDP was identified as the most effective practice. Full article

The conversion of carbon dioxide, a greenhouse gas, into valuable chemicals using sunlight is highly significant technologically and holds the promise of providing a more sustainable alternative to fossil fuels. To effectively utilize the abundant solar irradiation, it is essential to develop catalysts that can absorb a significant portion of the solar spectrum, particularly in the UV, visible, and infrared regions. Silicon nanowire arrays grown on silicon substrates meet this criterion, as they can absorb over 85% of solar irradiation and show minimal reflective losses across the UV, visible, and infrared portions of the solar spectrum. Herein, we report the deposition of various catalysts, including iron oxyhydroxides, copper, nickel, and ruthenium, on silicon nanowires using different catalyst deposition techniques. The photocatalytic reduction of carbon dioxide was evaluated using these catalysts. The results show that silicon nanowires coated with nickel and ruthenium oxide had the highest activity towards the photocatalytic reduction of carbon dioxide, with photomethanation rates reaching 546 μmolg_cat⁻¹h⁻¹ for RuO₂@SiNWs and 278 μmolg_cat⁻¹h⁻¹ for Ni/NiO@SiNWs. Continued improvement of photocatalysts using nanostructured silicon supports could enable the development of solar refineries for converting gas-phase CO₂ into value-added chemicals and fuels. Full article

Monitoring energy consumption in response to rising temperatures has become extremely important in all regions of the globe. The energy required for cooling is a major challenge in West Africa, where the climate is predominantly tropical. Among the various methods for evaluating energy requirements, the degree-day method is best known for its ability to estimate the heating, ventilation, and air-conditioning (HVAC) requirements of buildings. This study used three decades of weather station data to assess the cooling degree days (CDD) in two major West African cities, Kano and Bamako, across a range of base temperatures from 22 °C to 30 °C. The results indicate an increase in cooling degree days for Kano, whereas Bamako experienced a decrease in these parameters over the same period. Nonetheless, Bamako required a relatively higher cooling demand for all base temperatures. Furthermore, the study showed that the years 1998 and 2015 had the most significant impact on Kano and Bamako, with CDD values ranging from 2220 °C-day to 218 °C-day for Kano and from 2425 °C-day to 276 °C-day for Bamako. The study also found that a lower base temperature leads to higher energy consumption, while a higher base temperature leads to lower energy consumption. This information provides a useful reference for governments and policymakers to achieve energy efficiency and reduce greenhouse gas emissions. Full article

Nitrous oxide (N₂O) ranks as the third most significant greenhouse gas, capable of depleting the ozone layer and posing threats to terrestrial ecosystems. Climate change alters precipitation variability, notably in terms of frequency and magnitude. However, the implications of precipitation variability on N₂O emissions and the underlying mechanisms remain inadequately understood. In this study, employing laboratory incubation methods on three representative sandy soil types (sandy soil, shrub soil, and crust soil), we examined the impacts of diverse precipitation levels (5 mm and 10 mm) and frequencies (7 days and 14 days) on N₂O emissions from these soil types. This study aims to clarify the complex connections between soil N₂O emission fluxes and soil physicochemical properties in the soil environment. Our findings reveal that the N₂O emission flux exhibits heightened responsiveness to 5 mm precipitation events and a 14-day precipitation frequency, and compared to other treatments, the 5 mm precipitation and 14-day precipitation frequency treatment resulted in a 20% increase in cumulative nitrous oxide emissions. Consequently, cumulative N₂O emissions were notably elevated under the 5 mm precipitation and 14-day precipitation frequency treatments compared to the other experimental conditions. The N₂O emission flux in sandy soil displayed a positive correlation with available phosphorus (AP) and a negative correlation with pH, primarily attributed to the exceedingly low AP content in sandy soil. In shrub soil, the soil N₂O emission flux exhibited a significant positive correlation with NH₄⁺-N and a negative correlation with NO₃⁻-N. Conversely, no significant correlations were observed between soil N₂O emission flux and soil physicochemical properties in crust soil, underscoring the importance of considering plant–soil microbial interactions. Our findings suggest that soil nitrous oxide emissions in arid and semi-arid regions will be particularly responsive to small and frequent rainfall events as precipitation patterns change in the future, primarily due to their soil physicochemical characteristics. Full article

Most of our energy consumption proceeds from the use of fossil fuels and the production of natural gas. However, the presence of impurities in this gas, like CO₂, makes treatment necessary to avoid further concerns, such as greenhouse gas emissions, the corrosion of industrial equipment, etc.; thus, the development of CO₂ capture and storage procedures is of the utmost importance in order to decrease CO₂ production and mitigate its contribution to global warming. Among the CO₂ capture processes available, three separation technologies are being used to achieve this goal: absorption, adsorption and membranes. To overcome some limitations of these methodologies, the joint use of these technologies with ionic liquids is gaining interest. The present work reviewed the most recent developments (for 2024) in CO₂ capture using ionic liquids coupled to absorption-, adsorption- or membrane-based processes. Full article

The 21st century climate crisis has been compounded by the COVID-19 health crisis and the Russian war. What at first appeared to be an opportunity to move towards sustainable growth and development has turned into the opposite. In this context, it seems necessary to pause and analyze what countries are doing and where they are heading in order to ensure that their environmental efforts are not in vain. This article analyzes the environmental policies of the seven countries emitting the most GHGs from 1990 to the present day and compares them with the reality of their emissions. These behaviors are extrapolated into the future and, finally, conclusions are drawn as to which countries are not fully living up to their commitments, which have implemented the most effective measures, and where particular attention needs to be directed for maximum efficiency in decarbonizing the energy mix. Full article

As urbanization accelerates globally, urban areas have become major sources of greenhouse gas emissions. In this context, urban parks are crucial as significant components of carbon sinks. Using Shanghai Century Park as a case study, this study aims to develop an applicable and reliable workflow to accurately assess the carbon sequestration capacity of urban parks from a spatial–temporal perspective. Firstly, the random forest model is employed for biotope classification and mapping in the park based on multi-source data, including raw spectral bands, vegetation indices, and texture features. Subsequently, the Net Primary Productivity and biomass of different biotope types are calculated, enabling dynamic monitoring of the park’s carbon sequestration capacity from 2018 to 2023. Moreover, the study explores the main factors influencing changes in carbon sequestration capacity from the management perspective. The findings reveal: (1) The application of multi-source imagery data enhances the accuracy of biotope mapping, with winter imagery proving more precise in classification. (2) From 2018 to 2023, Century Park’s carbon sequestration capacity showed a fluctuating upward trend, with significant variations in the carbon sequestration abilities of different biotope types within the park. (3) Renovation and construction work related to biotope types significantly impacted the park’s carbon sequestration capacity. Finally, the study proposes optimization strategies focused on species selection and layout, planting density, and park management. Full article

Photovoltaic (PV) and wind energy generation result in low greenhouse gas footprints and can supply electricity to the grid or generate hydrogen for various applications, including seasonal energy storage. Designing integrated wind–PV–electrolyzer underground hydrogen storage (UHS) projects is complex due to the interactions between components. Additionally, the capacities of PV and wind relative to the electrolyzer capacity and fluctuating electricity prices must be considered in the project design. To address these challenges, process modelling was applied using cost components and parameters from a project in Austria. The hydrogen storage part was derived from an Austrian hydrocarbon gas field considered for UHS. The results highlight the impact of the renewable energy source (RES) sizing relative to the electrolyzer capacity, the influence of different wind-to-PV ratios, and the benefits of selling electricity and hydrogen. For the case study, the levelized cost of hydrogen (LCOH) is EUR 6.26/kg for a RES-to-electrolyzer capacity ratio of 0.88. Oversizing reduces the LCOH to 2.61 €/kg when including electricity sales revenues, or EUR 4.40/kg when excluding them. Introducing annually fluctuating electricity prices linked to RES generation results in an optimal RES-to-electrolyzer capacity ratio. The RES-to-electrolyzer capacity can be dynamically adjusted in response to market developments. UHS provides seasonal energy storage in areas with mismatches between RES production and consumption. The main cost components are compression, gas conditioning, wells, and cushion gas. For the Austrian project, the levelized cost of underground hydrogen storage (LCHS) is 0.80 €/kg, with facilities contributing EUR 0.33/kg, wells EUR 0.09/kg, cushion gas EUR 0.23/kg, and OPEX EUR 0.16/kg. Overall, the analysis demonstrates the feasibility of integrated RES–hydrogen generation-seasonal energy storage projects in regions like Austria, with systems that can be dynamically adjusted to market conditions. Full article

In the forthcoming years, it is expected that there will be a notable increase in the market penetration of electrically powered trucks with the objective of reducing greenhouse gas emissions in the transport sector. It is therefore essential to implement a comprehensive public charging infrastructure along highways in the medium term, enabling vehicles to be charged overnight or during driving breaks, particularly in the context of long-distance transportation. This paper presents a simulation model that supports the planning and technical design of truck charging parks at German highway rest areas. It also presents a transferable mobility model for the volume of trucks and the parking times of long-distance trucks at rest areas. Subsequently, a simulation is offered for the purpose of designing the charging infrastructure and analysing peak loads in the local energy system. The potential of the models is demonstrated using various charging infrastructure scenarios for an exemplary reference site. Subsequently, the extent to which the charging infrastructure requirements and the service quality at the location depend on external conditions is explained. In addition, the influence of the range of offers and the business models on the efficiency of infrastructure use is established. Based on the findings, general recommendations for the design of truck charging parks at rest areas are then given and discussed. Full article