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The upcoming network investment decisions and regulatory framework adopted by distribution system operators (DSOs) are most likely to be impacted by the integration of fluctuating distributed generation. The economical hosting capacity (HC) improvement method is investigated in this paper as a trade‐off between curtailment and upgrade using a Monte Carlo simulation procedure. The associated costs of both methods are vital indicators for network operators that are trying to maximize the HC and minimize cost. In addition, the breakeven point where curtailment and upgrade costs intersect is the decisive point at which network upgrade becomes sensible as marginal curtailment cost exceeds upgrade cost. A shift in global climate conditions can impact the photovoltaic (PV) levels that motivate network operators to investigate PV penetration, especially in colder climate regions. Thus, the primary objective of this paper is to investigate the shift of the breakeven point to guide DSOs to either adopt PV curtailment as a temporary measure or grid upgrade as a risk aversion strategy considering Finnish climate and load patterns. The real‐time load and PV generation data are utilized for the simulations to consider the dynamic performance indication of three Finnish distribution networks. Curtailment remains a low‐cost option to obtain a percentage HC rise of 13%, 7%, and 8% for rural, suburban, and urban regions, respectively, beyond which curtailment compensation cost surpasses upgrade cost. In essence, PV curtailment serves as an immediate and least‐cost solution to relieve network violations and defer network investment until the HC level (118%, 106%, 97%) making the upgrade a practical option afterwards. [ABSTRACT FROM AUTHOR]

The effectiveness of Carbon Capture and Storage (CCS) as an imperative decarbonization technology relies on the sealing capacity of a fine‐grained caprock to permanently store CO2 deep underground. Uncertainties in assessing the caprock sealing capacity increase with the spatial and temporal scales and may delay CCS deployment at the gigatonne scale. We have developed a computationally efficient transport model to capture the dynamics of basin‐wide upward CO2 migration in a multi‐layered setting over geological time scales. We find that massive capillary breakthrough and viscous flow of CO2, even through pervasively fractured caprocks, are unlikely to occur and compromise the storage security. Potential leakage from the injection reservoir is hampered by repetitive layering of overlying caprocks. This finding agrees with geologic intuition and should be understandable by the public, contributing to the development of climate policies around this technology with increased confidence that CO2 will be indefinitely contained in the subsurface. Plain Language Summary: Massive and timely deployment of Carbon Capture and Storage (CCS) at the gigatonne scale is a critical component of the majority of pathways toward reaching the Paris Agreement emissions abatement targets to mitigate climate change. Although CCS has been successfully deployed at multiple sites around the world, concerns about long‐term containment, especially for gigatonne‐scale storage, are causing uncertainty about the ability of geological layers to permanently store CO2 underground. This uncertainty is delaying the widespread deployment of CCS. This paper focuses on assessing the possibility of basin‐wide CO2 leakage through a typical multi‐layered geological setting with a sequence of aquifers and fine‐grained caprocks (e.g., shales). Numerical transport models, constrained by hydraulic properties of intact and pervasively fractured caprocks (as the best‐ and worst‐case scenarios, respectively), enable us to draw unambiguous limits on the CO2 leakage rates over previously unexplored temporal and spatial scales. We show that CO2 leakage to shallow sediments in both extreme scenarios is quite unlikely and the injected CO2 will be contained in the subsurface over millions of years. These findings should offer confidence to industrial developers, policy‐makers, investors, and most importantly, the public that CCS provides a secure and environmentally sound carbon removal option. Key Points: We develop a numerical transport model to understand the long‐term fate of CO2 in gigatonne‐scale geologic carbon storageCO2 leakage is dominated by molecular diffusion at inherently slow rates, hardly approaching a meter per several thousands of yearsThe long‐term potential for CO2 leakage from a multi‐layered system is low, making geologic storage a secure decarbonization technology [ABSTRACT FROM AUTHOR]

As part of the climate policy to meet the 2 °C target, actions in all economic sectors, including agriculture, are required to mitigate global greenhouse gas emissions. While there has been an ever‐increasing focus on agricultural greenhouse gas (AGHG) emissions, limited attention has been paid to their economic drivers in the globalized world economy and related mitigation potentials. This paper makes a first attempt to trace AGHG emissions via global trade networks using a multiregional input‐output model and a complex network model. Over one third of global AGHG emissions in 2012 can be linked with products traded internationally, of which intermediate trade and final trade contribute 64.2% and 35.8%, respectively. Japan, the United States, Germany, the United Kingdom, and Hong Kong are the world's five largest net importers of embodied emissions, while Ethiopia, Australia, Pakistan, India, and Argentina are the five largest net exporters. Some hunger‐afflicted developing countries in Asia and Africa are important embodied emission exporters, due to their large‐scale exports of agricultural products. Trade‐related virtual AGHG emission transfers shape a highly heterogenous network, due to the coexistence of numerous peripheral economies and a few highly connected hub economies. The network clustering structure is revealed by the regional integration of several trading communities, while hub economies are collectors and distributors in the global trade network, with important implications for emission mitigation. Achieving AGHG emission reduction calls for a combination of supply‐ and demand‐side policies covering the global trade network. Key Points: Over one third of global AGHG emissions can be linked with intermediate trade (64.2%) and final trade (35.8%)Trade‐related virtual AGHG emission transfers shape a highly heterogenous networkThe hub economies are of great importance on global AGHG emission mitigation [ABSTRACT FROM AUTHOR]

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China is under pressure to improve its agricultural productivity to keep up with the demands of a growing population with increasingly resource-intensive diets. This productivity improvement must occur against a backdrop of carbon intensity reduction targets, and a highly fragmented, nutrient-inefficient farming system. Moreover, the Chinese government increasingly recognizes the need to rationalize the management of the 800 million tonnes of agricultural crop straw that China produces each year, up to 40% of which is burned in-field as a waste. Biochar produced from these residues and applied to land could contribute to China's agricultural productivity, resource use efficiency and carbon reduction goals. However competing uses for China's straw residues are rapidly emerging, particularly from bioenergy generation. Therefore it is important to understand the relative economic viability and carbon abatement potential of directing agricultural residues to biochar rather than bioenergy. Using cost-benefit analysis ( CBA) and life-cycle analysis ( LCA), this paper therefore compares the economic viability and carbon abatement potential of biochar production via pyrolysis, with that of bioenergy production via briquetting and gasification. Straw reincorporation and in-field straw burning are used as baseline scenarios. We find that briquetting straw for heat energy is the most cost-effective carbon abatement technology, requiring a subsidy of $7 MgCO2e−1 abated. However China's current bioelectricity subsidy scheme makes gasification ( NPV $12.6 million) more financially attractive for investors than both briquetting ( NPV $7.34 million), and pyrolysis ($−1.84 million). The direct carbon abatement potential of pyrolysis (1.06 MgCO2e per odt straw) is also lower than that of briquetting (1.35 MgCO2e per odt straw) and gasification (1.16 MgCO2e per odt straw). However indirect carbon abatement processes arising from biochar application could significantly improve the carbon abatement potential of the pyrolysis scenario. Likewise, increasing the agronomic value of biochar is essential for the pyrolysis scenario to compete as an economically viable, cost-effective mitigation technology. [ABSTRACT FROM AUTHOR]

The Latin America and the Caribbean (LAC) region plays key roles in both meeting global agricultural demands and maintaining carbon sinks due to its abundant land and water resources. In this study we use the Global Change Analysis Model to evaluate the opportunities and challenges posed by two global‐scale drivers: agricultural market integration (i.e., reduction of trade barriers) and land‐based climate mitigation policy. We evaluate their potential individual and combined impacts on agricultural production and trade revenues across LAC's economies through mid‐century, as well as the resulting impacts on agricultural consumers and integrated land‐water‐climate systems across LAC's diverse sub‐regions. Increased global market integration results in increased agricultural production and trade revenues for many LAC economies, driven by their evolving comparative advantages. Climate mitigation measures on CO2 and non‐CO2 greenhouse gases increase revenues due to increased agricultural prices from land competition and emissions abatement. The combined outcomes from both drivers are complex and sometimes non‐linear, highlighting the importance of understanding the interactions between multiple drivers. Our results show that increased agricultural production and trade opportunities, from either of the two drivers, pose significant trade‐offs that require careful multi‐sectoral planning, such as emissions reduction challenges, potential loss of livestock production when pursuing land‐based climate mitigation strategies, increased consumer expenditures, and changes in land‐use or water withdrawals, resulting in deforestation or water scarcity pressures. There is considerable heterogeneity in economic and environmental outcomes across LAC sub‐regions and agricultural commodities, illustrating the value of considering outcomes at finer scales. Key Points: Latin America plays a key role in meeting global agricultural demands in a world with more interconnected tradeClimate mitigation raises agricultural production prices and shifts livestock trade patterns based on emissions reduction potentialAgricultural production and trade opportunities have trade‐offs on increased consumer expenditures and impacts on land, water, and climate [ABSTRACT FROM AUTHOR]

Using a fossil fuel extraction model that treats the atmosphere as a depletable resource, we study the optimal price of carbon in the presence of endogenous uncertainty around a climatic regime shift. We find that the optimal carbon tax should account an uncertainty‐adjusted cost term associated with the environment's scarcity. This term is shown to be sensitive to the natural sequestration rate of the atmosphere and to the probability surrounding a climate tail event. Our analysis also shows that in the presence of uncertainty, the shadow price of the environment should grow at a faster rate. Lastly, compared to the endogenous uncertainty case, we find that if the probability surrounding a regime shift is exogenously given, this shadow price should even grow at a higher rate. Considerations for Management: Based on our theoretical analysis, considerations for resource management may include: •Beside direct damages, optimal carbon pricing should account for a cost term related to the environment's scarcity.•As the probability of facing an extreme climate event increase, this cost term amplifies.•The cost term disappears for a sufficiently high abatement effort.•Compared to endogenous uncertainty, exogenous uncertainty enforces placing a higher value on the environment's shadow price. [ABSTRACT FROM AUTHOR]

Cu2+ ions (ZCu2+(OH)−, Z2Cu2+) are regarded as the NH3‐SCR (SCR=selective catalytic reduction) active site precursors of Cu‐exchanged chabazite (CHA) which is among the best available catalysts for the abatement of NOx from Diesel engines. During SCR operation, copper sites undergo reduction (Reduction half‐cycle, RHC: Cu2+→Cu+) and oxidation (Oxidaton half‐cycle, OHC: Cu+→Cu2+) semi cycles, whose associated mechanisms are still debated. We recently proposed CO oxidation to CO2 as an effective method to probe the formation of multinuclear Cu2+ species as the initial low‐T RHC step. NH3 pre‐adsorption determined a net positive effect on the CO2 production: by solvating ZCu2+(OH)− ions, ammonia enhances their mobility, favoring their coupling to form binuclear complexes which can catalyze the reaction. In this work, dry CO oxidation experiments, preceded by modulated NH3 feed phases, clearly showed that CO2 production enhancements are correlated with the extent of Cu2+ ion solvation by NH3. Analogies with the SCR‐RHC phase are evidenced: the NH3‐Cu2+ presence ensures the characteristic dynamics associated with a second order kinetic dependence on the oxidized Cu2+ fraction. These findings provide novel information on the NH3 role in the low‐T SCR redox mechanism and on the nature of the related active catalyst sites. [ABSTRACT FROM AUTHOR]

Human activities have altered the environmental controls on river metabolism, i.e., gross primary production (GPP) and ecosystem respiration (ER). These coupled processes affect water quality, CO2 emissions, and biodiversity. Efforts to mitigate these impacts often lack long‐term, high‐resolution data needed to assess their success. Here, we estimated a 20‐yr time series of daily metabolism from dissolved oxygen (DO) data following pollution abatement (sewage treatment) in the Oria River, Spain. Ammonium concentration declined immediately after sewage abatement, whereas dissolved organic matter absorbance (proxy for concentration) declined slowly. Summer GPP declined with ammonium concentration. ER declined more strongly but more gradually than GPP and was driven by lower rates of autotrophic respiration (AR) and heterotrophic respiration following sewage treatment. Reduced AR reflected a decrease in the fraction of daily GPP being respired by algae themselves. Decline in ER caused net ecosystem production to increase from highly negative to approximately zero. Diel DO swings also declined and episodes of hypoxia nearly disappeared following reduced metabolic rates, and were paralleled by lower benthic chlorophyll a, increased macroinvertebrate indices, and a recovery of fish assemblages. Overall, wastewater treatment plants installation constrained river metabolism, greatly improved water quality, and enabled invertebrates and fish to recolonize the river. However, most variables responded gradually and these changes would not have been evident with short‐term DO data. These gradual responses revealed the need of long‐term, high‐resolution data to gain insight into long‐temporal scale responses superimposed on short‐temporal scale metabolic variation, especially in the current context of climate and land‐use change. [ABSTRACT FROM AUTHOR]

High pollution persists in many developing countries despite strict environmental rules. We use a field experiment and a structural model to study how plant emission standards are enforced. In collaboration with an Indian environmental regulator, we experimentally doubled the rate of inspection for treatment plants and required that the extra inspections be assigned randomly. We find that treatment plants only slightly increased compliance. We hypothesize that this weak effect is due to poor targeting, since the random inspections in the treatment found fewer extreme violators than the regulator's own discretionary inspections. To unbundle the roles of extra inspections and the removal of discretion over what plants to target, we set out a model of environmental regulation where the regulator targets inspections, based on a signal of pollution, to maximize plant abatement. Using the experiment to identify key parameters of the model, we find that the regulator aggressively targets its discretionary inspections, to the degree that half of the plants receive fewer than one inspection per year, while plants expected to be the dirtiest may receive ten. Counterfactual simulations show that discretion in targeting helps enforcement: inspections that the regulator assigns cause three times more abatement than would the same number of randomly assigned inspections. Nonetheless, we find that the regulator's information on plant pollution is poor, and improvements in monitoring would reduce emissions. [ABSTRACT FROM AUTHOR]

Abstract: Conceptual design using multi‐bed series reactors consisting of catalysts and adsorbent beds was performed for a new SF6 abatement and utilization technology free of toxic chemicals to reduce SF6 emissions and produce valuable products like CaF2 and CaSO4 simultaneously. With process simulation studies using Aspen HYSYS®, comparative studies for a single‐bed reactor (SR‐1), a two‐bed series reactor (SR‐2), and a three‐bed series reactor (SR‐3) revealed that more CaF2 and CaSO4 were produced in multi‐bed series reactors compared to a SR‐1 (SR‐3 > SR‐2 > SR‐1) possibly due to sorption‐enhanced hydrolysis. In addition, lower operating temperatures were observed in multi‐bed series reactors (TSR1 > TSR2 > TSR3) showing the positive effect of using multi‐bed series reactors for a simultaneous SF6 abatement and utilization technology. [ABSTRACT FROM AUTHOR]

The performance of alumina- and magnesia-based carbon-containing refractory castables, suitable for different sectors of steel plants, has been compared. Natural flaky graphites have been modified by their surface treatment via sol-gel route. The sustainability of graphite in oxidizing atmosphere was noticeably increased by this method with a synergistic possibility of pollution abatement. The hydrophilic nanocoatings of ceramic oxides derived by inorganic precursors reduced the water demand of the composite batch and simultaneously enhanced its oxidation resistance. The oxide coating compositions together with the precursor chemistry have been varied to substantiate their common beneficial features. Scanning electron microscopy ( SEM), Raman spectroscopy, Differential thermal analysis ( DTA), Thermogravimetry ( TG), X-ray diffraction, thermal conductivity, and zeta-potential studies have been carried out to compare the influence of heat treatment on as-received and surface-modified graphites. The properties of refractory castables, namely, bulk density, apparent porosity, and cold crushing strength have been measured within wide temperature region (110-1500°C), to confirm the positive influence of nanoengineering on graphite surface. The sequence of important phase reactions during sintering of both the composite materials has been discussed. Finally the slag resistance behavior at aggressively fired condition has been investigated to corroborate the improved matrix characteristics due to coated graphites. [ABSTRACT FROM AUTHOR]

We investigated the feasibilities of 2.0°C and 1.5°C climate targets by considering the abatement potentials of a full suite of greenhouse gases, pollutants, and aerosols. We revised the inter-temporal dynamic optimization model DICE-2013R by introducing three features as follows. First, we applied a new marginal abatement cost curve derived under moderate assumptions regarding future socioeconomic development-the Shared Socioeconomic Pathways 2 ( SSP2) scenario. Second, we addressed emission abatement for not only industrial CO2 but also land-use CO2, CH4, N2O, halogenated gases, CO, volatile organic compounds, SO x, NO x, black carbon and organic carbon. Third, we improved the treatment of the non-CO2 components in the climate module based on MAGICC 6.0. We obtained the following findings: (1) It is important to address the individual emissions in an analysis of low stabilization scenarios because abating land-use CO2, non-CO2 and aerosol emissions also contributes to maintaining a low level of radiative forcing and substantially affects the climate costs. (2) The 2.0°C target can be efficiently reached under the assumptions of the SSP2 scenario. (3) The 1.5°C target can be met with early deep cuts under the assumption of a temperature overshoot, and it will triple the carbon price and double the mitigation cost compared with the 2.0°C case. [ABSTRACT FROM AUTHOR]

We analyse bargaining over international climate agreements in a setting with incomplete information about abatement costs. Incomplete information is known as one of the key reasons why negotiations may fail more generally, and why efficiency gains cannot be exploited. We ask whether unilateral commitment to high abatement reduces or increases the likelihood for an efficient negotiation outcome. We find that such commitment behaviour reduces the gains from global cooperation and that, in turn, this reduces the probability of reaching efficient international environmental agreements. [ABSTRACT FROM AUTHOR]

Over a period of 24 months of operation, we optimised a physicochemical plant for the decontamination of surface treatment industrial wastewater. This article presents the abatements obtained in the levels of chemical pollution after the various optimisations validated in the laboratory and then transposed to the industrial site. The optimisation of the plant reduced the effluent organic load, nitrite and zinc levels by about 70%, 85% and 80%, respectively. To evaluate the utility of each optimisation proposal, standard bioassays based on lettuce seed germination were carried out on the final effluent. Decreasing concentrations of pollutants in the effluent led to a reduction of its impact on seed germination. The bioassays confirmed the environmental benefits obtained from the optimisation of the treatment plant. The biological tests proposed seem to be good indicators of the contaminant concentrations present in wastewater. [ABSTRACT FROM AUTHOR]