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Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Analyzes intermediaries facilitating wooden multi-storey construction in Finland. • Regime and niche intermediaries were identified to be most prominent. • Multiple goals, over-lapping roles and means of policy influencing among the actors. • User and process intermediaries, considered important for transitions, were missing. • Low level of coordination likely reducing effectiveness of intermediaries. Intermediaries can potentially help reduce institutional lock-ins that slow down sustainability transitions by influencing policy processes, because of their connectedness and often high level of legitimacy. In this paper, we analysed intermediaries seeking to accelerate the diffusion of wooden multi-storey construction (WMC) in Finland, their roles and engagement in policy processes. Increasing the use of wood in construction has high policy support nationally, backed up with climate and forest policies. Yet, market diffusion has been slow. The data consist of qualitative interviews of intermediaries and other actors, participatory observation and a review of secondary materials. The results reveal a complex set of intermediaries, including systemic, niche and regime-based ones. The intermediaries are characterised by multiple goals, partly over-lapping roles and means of policy influencing. The low degree of coordination among the intermediaries and the differences in their agenda for transition are critical challenges which limit the effectiveness of their actions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Low-carbon economy is gaining growing attention nowadays as global warming intensifies. As a market-based policy, emission trading policy is widely considered an effective means to achieve the doublewin of economic development and environmental protection. Under such circumstances, carbon trading markets are developing rapidly in many countries and regions, demanding more attention to compliance strategy issues for emission-intensive companies. In this study, we build a dynamic programming model in search of the optimal emission trading and technology investment decisions for a make-to-order company faced with a stochastic demand under emission trading policy. After a comprehensive analysis of the proposed model, we find that an optimal emission permit level, which increases in carbon penalty and decreases in carbon price, exists in each period. As for the abatement technology investment decision, the firm should invest only if the investment cost per unit of abatement effort is less than a certain threshold, which increases in carbon penalty and carbon price. On the basis of a two-period dynamic programming model, we further explore the problem of investment timing. Results show how optimal investment decisions are influenced by the speed of technology progress under different parameters. These findings are important for firms to choose the time of investment depending on specific situations. [ABSTRACT FROM AUTHOR]

Can growth-oriented resource-intensive cities be redesigned as non-consumptive sustainable places in a climate constrained world? This research tests that proposition through a design exploration of the transformation of a 500-ha inner city industrial district in Calgary, Canada, to a sustainable low-carbon city district. The research is formulated with respect to three theoretical axis—theories of urbanism, complexity and transitions; three spatial moments of the production process—production, reproduction and consumption and three temporal moments of the production process—manufacture, use, and post-use. The spatial and temporal moments leverage models of, industrial ecology and circular economy, sustainable cities and derivatives including smart, post-carbon and eco-cities. We employ a participatory design and backcasting methodology informed by theories of path dependence/creation. We establish a set of performance criteria, conduct three rounds of participatory design explorations and follow a strategy of scale-up of existing technology, engineering and design precedents. We identify a set of eight barriers and associated mitigation strategies. These include the stigma of living adjacent to, and the cost to rehabilitate, industrial lands; spatial and cultural auto-dependence; fragmentation of land ownership; infrastructure financing; regional connectivity and path dependence of the planning process. We propose that in order to achieve socially, ecologically and economically sustainable low-carbon cities attention needs to be addressed to culturally transformative alternatives to automobility, new forms of cooperative and localized economy, provision of non-market modes of land development and democratic and regulatory reform. To conclude we reformulate our conceptual framework within three nested domains—socio-technical, econo-political and cultural–cosmological. [ABSTRACT FROM AUTHOR]

This study presents, for the first time, a universal theoretical framework based on machine learning (ML) algorithms for the multi-objective optimization (MOO) design of 3D printing low-carbon concrete to meet the sustainability requirements of the construction industry. The study focuses on the simultaneous reduction of carbon emissions and costs during the design process. Specifically, the applicable scenarios are primarily classified into two categories: meet aesthetics requirements (printing layer height error-HE and printing layer width error-WE approaching 0) and strengths requirements (compressive strength-CS approaching 60 MPa and interlayer bonding strength-IBS as high as possible). Through a comparison with the traditional design method, 3D printing concrete based on the intelligent design method achieves a 44% reduction in costs and a 19% reduction in carbon emissions while meeting aesthetics requirements. Under strengths requirements, there is a 57% reduction in costs and a 22% reduction in carbon emissions. This demonstrates the indispensable and crucial role of the MOO method employed in this study in achieving the lowest costs and carbon emissions. Additionally, the results of experimental verification demonstrate that the models developed in this study have successfully achieved a close alignment between design values and experimental values within the allowable error range (The errors are 3.46%–9.83%). This not only holds the potential to drive the widespread application of 3D printing technology in the construction industry but also presents new possibilities for cleaner production, contributing to the achievement of sustainable development goals. [Display omitted] • The prediction model for 3D printing concrete rheological properties was established. • The prediction model for 3D printing concrete printability was established. • The prediction model for 3D printing concrete strengths was established. • Multi-objective optimization design of 3D printing low-carbon concrete was performed. • The effectiveness of multi-objective optimization design was verified by experiments. [ABSTRACT FROM AUTHOR]

• A non-sintering strategy for preparing solid thermal energy storage materials. • The composite binder ensures the satisfied strength of materials at any temperature. • The material exhibits stable thermal cycling performance (400–1000 °C). • The non-sintering preparation greatly reduces CO 2 emissions and production costs. In recent years, the rapid growth of clean energy has driven the rapid development of solid thermal energy storage (STES) technology in China. However, the preparation process of commonly used sintered magnesia bricks have the problems of high carbon emissions (7 t CO 2 /t brick) and high cost, which limits the large-scale application of STES technology. This paper proposes a non-sintering strategy for preparing bauxite-based STES materials. The results demonstrate that the prepared material exhibits good mechanical strength at both room temperature (>15 MPa) and medium-to-high temperatures (>10 MPa), resistance to high-temperature creep (>1250 °C), acceptable thermal conductivity (2.23 W·m−1·K−1), and stable thermal cycling performance with a flexural strength of at least 10 MPa after 20 thermal cycles (400–1000 °C), which satisfies the demand for high-temperature energy storage. Furthermore, the carbon emissions of the non-sintering material is only 30 % of that of sintered magnesia brick, and the production costs are significantly reduced, making them a promising alternative to current sintered STES bricks. [ABSTRACT FROM AUTHOR]

This study identifies supply options for sustainable urban energy systems, which are robust to external system changes. A multi-criteria optimization model is used to minimize greenhouse gas (GHG) emissions and financial costs of a reference system. Sensitivity analyses examine the impact of changing boundary conditions related to GHG emissions, energy prices, energy demands, and population density. Options that align with both financial and emission reduction and are robust to system changes are called "no-regret" options. Options sensitive to system changes are labeled as "potential-risk" options. There is a conflict between minimizing GHG emissions and financial costs. In the reference case, the emission-optimized scenario enables a reduction of GHG emissions (− 93 %), but involves higher costs (+ 160 %) compared to the financially-optimized scenario. No-regret options include photovoltaic systems, decentralized heat pumps, thermal storages, electricity exchange between sub-systems and with higher-level systems, and reducing energy demands through building insulation, behavioral changes, or the decrease of living space per inhabitant. Potential-risk options include solar thermal systems, natural gas technologies, high-capacity battery storages, and hydrogen for building energy supply. When energy prices rise, financially-optimized systems approach the least-emission system design. The maximum profitability of natural gas technologies was already reached before the 2022 European energy crisis. • Impacts of changing boundary conditions on optimized urban energy systems are analyzed. • No-regret options are, e.g., heat pumps, thermal storages, and electricity exchange. • Potential-risk options are, e.g., solar thermal, natural gas, and hydrogen usage. • When energy prices rise, cost-optimized systems approach emission-optimized systems. • Natural gas usage has reached max. viability before the 2022 European energy crisis. [ABSTRACT FROM AUTHOR]

The dumping of titanium slag (TS) and fly ash (FA) could lead to the occupancy of abundant land resources and the pollution of air, soil and underground water. The meso-regulatory function of the lightweight and thermally stable porous TS makes it a feasible material as the fire-resistive cementitious composites (FRCCs). This paper proposed a novel low-carbon FRCC with favorable high-temperature resistance by using TS and FA. Then, the mechanical properties and mechanism improving the heat resistance were systematically studied. The results revealed that the addition of TS with proper quantity decreases the mass loss by 19.6% and degradation degree of mechanical strength by 31.8% after 800 ℃ heating. The thermally stable perovskite and akermanite phases in TS are conducive to improving the stability of mineral phases during high-temperature heating. Meanwhile, the porous structure of TS enhances the thermal insulation of FRCC, which postponed the mineral phase decomposition. In addition, the secondary hydration effect of FA consumes a large amount of Ca(OH) 2 , which effectively weakens the deterioration caused by the decomposition of Ca(OH) 2 after 600 ℃ heating. Based on the CT results, the variations of internal pore structure including pore distribution, porosity, and fractal dimensions, were systematically analyzed. It is found that the TS particles can effectively optimize the internal pore distribution and limit the generation and deterioration of macro-pores. Moreover, the thermal damage model of the prepared FRCC was established by combining the pore structure deterioration degree and residual mechanical strength. Finally, compared with traditional fire-resistive fillers, the low carbon emission of the prepared FRCC was verified. • A novel low-carbon fire-resistive cementitious composites with favorable high-temperature resistance was prepared. • The action mechanisms of titanium slags on mineral phase evolution and heat resistance properties were elucidated. • The optimization effect of titanium slag on pore structure and limitation effect on pore deterioration were elucidated. • A thermal damage model was established by combining pore structure deterioration degree and residual mechanical strength. [ABSTRACT FROM AUTHOR]

Unreinforced masonry (URM) walls are highly susceptible to seismic events, especially in the out-of-plane direction, due to their weak tensile and flexural behavior. Moreover, the concrete industry is responsible for a large amount of CO2 emissions generated during the production of Portland cement. In response, the current study aims to investigate the out-of-plane response of URM walls externally strengthened with Textile Reinforced Mortar (TRM) where cement is partially replaced with natural zeolite. Eight double-wythe width brick walls were tested under three-point bending tests; including one reference wall and seven walls externally reinforced with different TRM configurations. Investigated parameters comprised of the number of textile layers, application on one or both faces, proficiency in using connectors, and the effect of natural zeolite as a substitution for cement. In addition, a series of tensile tests was also included as a part of the experimental campaign for further investigation of the interaction between textile and mortar in tension. Different proportion of the cement was replaced with natural zeolite to evaluate the effect of zeolite-based mortars on bonding between textile and mortar. Results of the three-bending test evidenced a significant increase in load-bearing capacity and ductility of reinforced specimens. The application of TRM with different reinforcement ratios indicated a direct impact on peak load. Connectors enhanced flexural capacity by providing better bonding between TRM and substrate. Natural zeolite in the TRM composition caused a reduction in terms of strength. Tensile tests consistently showed that the ultimate strength decreased as the amount of zeolite increased by 20% substitution. The results of the existing experimental data were evaluated against the analytical method presented by this study to determine the performance of each parameter. • Out-of-Plane Response of Masonry Walls strengthened with textile reinforced mortar under three-point bending tests. • Impact of TRM textile layers and Connectors. • Low-Carbon Mortar and Zeolite as Pozzolanic Materials. • Uniaxial Low-Carbon TRM Tensile Test. [ABSTRACT FROM AUTHOR]

• An innovative pilot-scale staged PN/A process developed to treat MLL. • Stable nitrogen removal (TN < 40 mg/L) was achieved under continuous flow. • Stable inhibition of NOB by low oxygen in combination with FA and FNA. • Salt-tolerant Kuenenia (33.4 %) dominated the ecological niche in anammox biofilm. • Dual biofilm membrane designed to keep effluent SS stable below 5 mg/L. The start-up and stable operation of partial nitritation-anammox (PN/A) treatment of mature landfill leachate (MLL) still face challenges. This study developed an innovative staged pilot-scale PN/A system to enhance nitrogen removal from MLL. The staged process included a PN unit, an anammox upflow enhanced internal circulation biofilm (UEICB) reactor, and a post-biofilm unit. Rapid start-up of the continuous flow PN process (full-concentration MLL) was achieved within 35 days by controlling dissolved oxygen and leveraging free ammonia and free nitrous acid to selectively suppress nitrite-oxidizing bacteria (NOB). The UEICB was equipped with an annular flow agitator combined with the enhanced internal circulation device of the guide tube, which achieved an efficient enrichment of Candidatus Kuenenia in the biofilm (relative abundance of 33.4 %). The nitrogen removal alliance formed by the salt-tolerant anammox bacterium (Candidatus Kuenenia) and denitrifying bacteria (unclassified SBR1031 and Denitratisoma) achieved efficient nitrogen removal of UEICB (total nitrogen removal percentage: 90.8 %) and at the same time effective treatment of the refractory organic matter (ROM). The dual membrane process of UEICB fixed biofilm combined with post-biofilm is effective in sludge retention, and can stably control the effluent suspended solids (SS) at a level of less than 5 mg/L. The post-biofilm unit ensured that effluent total nitrogen (TN) remained below the 40 mg/L discharge standard (98.5 % removal efficiency). Compared with conventional nitrification-denitrification systems, the staged PN/A process substantially reduced oxygen consumption, sludge production, CO 2 emissions and carbon consumption by 22.8 %, 67.1 %, 87.1 % and 87.1 %, respectively. The 195-day stable operation marks the effective implementation of the innovative pilot-scale PN/A process in treating actual MLL. This study provides insights into strategies for rapid start-up, robust NOB suppression, and anammox biomass retention to advance the application of PN/A in high-ammonia low-carbon wastewater. [ABSTRACT FROM AUTHOR]

3D concrete printing can be used for automatic repair, aiming at increasing efficiency and reducing the use of manpower, as compared to conventional manual repair. Ensuring strong adhesion of the 3D printed materials and characterizing the interface is crucial for the success of this approach. To this end, we first evaluated the adhesion performance of 3D printed concrete based on a low-carbon binder, i.e., calcium sulfoaluminate (CSA) cement. CSA cement pastes with different re-dispersible polymer powder substitution rates were used as coating before 3D printing. We used two approaches, X-ray computed tomography (CT) and scanning electron microscopy (SEM), to characterize the interface region. Results indicate that the yield stress of the 3D printing material and the coating material plays an important role in the adhesion in both the fresh and hardened state. Moreover, the limited adhesion at the overlay interface can be due to the limited contact at the centimeter and micro scale, as reflected by CT and SEM, respectively. Applying a coating can fill the air voids at the interface, while the placement of a coating may not improve the bond strength and can even have a negative impact due to the limited liquid medium at the interface. • Lower yield stress in the 3D printing material can enhance the contact area at the interface. • A coating with a higher yield stress promotes more excellent adhesion in the early stage by preventing slippage. • Applying a coating can enhance adhesion in the hardened state by filling the air voids. • X-ray computed tomography (CT) and scanning electron microscopy (SEM) are adopted to characterize the interface. [ABSTRACT FROM AUTHOR]

A region-based low-carbon operation analysis method for integrated electricity‑hydrogen-gas systems (IEHGSs) is proposed in this paper. The committed carbon emission operation region (CCE_OR) and the economic CCE_OR (ECCE_OR) are proposed to evaluate the low-carbon feasible space (LCFS) from the low-carbon, secure, and economic perspectives, which provides powerful tools for the low-carbon operation analyses of IEHGSs. Firstly, a coordinated mechanism of carbon flow and hydrogen flow is developed to excavate the low-carbon operation potential of IEHGSs. Then, based on the distributionally robust chance-constrained approach, the concepts and models of CCE_OR and ECCE_OR are defined and formulated considering uncertainties and hydrogen merits. Furthermore, a region model reformulation method is proposed to reformulate the uncertain and non-convex CCE_OR and ECCE_OR models into the deterministic and mixed-integer linear region models. The geometric properties of CCE_OR and ECCE_OR are both theoretically proven, which are the union set of finite convex and bounded polytopes. The united region solution methodology considering the geometric properties of CCE_OR and ECCE_OR is presented to effectively characterize CCE_OR and ECCE_OR. Finally, the numerical results on two test systems verify the effectiveness and applicability of the proposed methods. Simulation results indicate that the proposed methods can improve the LCFS, characterize visual coupling relationships between LCFS and observation variables, and provide comprehensive low-carbon operation information of operation points. • The coordinated mechanism of carbon flow and hydrogen flow is developed to excavate the low-carbon operation potential. • The committed carbon emission operation region (CCE_OR) and the economic CCE_OR (ECCE_OR) are defined and formulated. • The unified region solution methodology considering the geometric properties of CCE_OR and ECCE_OR is established. • The low-carbon feasible space (LCFS) capturing comprehensive operation information is characterized. • The merits and restrictions of zero-carbon characteristics of hydrogen on LCFS are revealed. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of varying investment costs in a cost-optimal portfolio of electricity-generating technologies to achieve a low-carbon power system to help mitigate climate emissions in Finland. Several different cost scenarios for nuclear, solar, wind, and battery technologies are constructed, considering both single- and multi-stage investment-strategy pathways, with sector coupling of the power system to the heating sector and hydrogen production. Potential new nuclear investments are assumed small modular reactors capable of flexible operation, and optional additional flexibility measures from heating and hydrogen sectors are considered. The scenarios are simulated with hourly resolution using GenX, an openly available capacity expansion optimization tool. Across a wide range of assumed investment costs, the results demonstrate a clear role for flexible nuclear power as a provider of both a solid base generation and flexibility to enhance integration of intermittent wind to the system. Despite optimistic cost assumptions for solar and batteries, their role is observed to remain marginal in the Finnish setting, likely due to large seasonal variation in the local solar availability. [Display omitted] • Nuclear SMR is deployed in all cost scenarios studied. • Nuclear SMR provides both baseload and flexibility. • Load flexibility increases wind deployment and lowers system costs. • Increasing hydrogen production increases nuclear SMR capacity. [ABSTRACT FROM AUTHOR]

Increasing deployment of wind power into integrated energy system becomes a critical pathway for deep decarbonizing the power sector. It is imperative to investigate the impacts of uncertain wind power on integrated power system as the result of the heavy interdependencies among different types of energy in supplying the requirements of economy, low carbon and risk aversion. Here, the concept of fuzzy semi-entropy is presented to quantify the downside risk of uncertain wind power. After that, a mean-semi-entropy model for low-carbon oriented electrical-gas-heat energy system including carbon emission, carbon capture and carbon trading is proposed. In particular, the dependence of wind power outputs from different wind turbines is investigated by the multivariate Gaussian Copula. Results obtained from case studies demonstrate the feasibility of the proposed model in achieving a balanced trade-off among system economy, low carbon emission and operation risk properly. The proposed model enables the reduction in total cost and carbon emission by 2.29% and 5.18% in comparison to these of traditional cost minimization model. In addition, the accommodation level of wind power with multivariate Gaussian Copula improves by 2.17% compared to that without considering coupling. • Low-carbon technologies considering emission deviations are studied. • A credibility theory-based semi-entropy is presented for downside risk. • The multivariate Gaussian Copula is developed to study the dependence. • The model can be easily extended to other energy system optimizations. [ABSTRACT FROM AUTHOR]

• A two-stage coordinated planning framework is proposed. • A siting optimization submodel for energy station and supply network is proposed. • A sizing optimization submodel for energy devices and pipelines is proposed. Coordinated siting and sizing for energy stations and supply networks in low-carbon park-level integrated energy systems are significant for economic improvement and carbon emissions reduction. To minimize total planning costs and carbon emissions of park-level integrated energy systems, a two-stage coordinated siting and sizing framework for the energy station and supply network of a low-carbon park-level integrated energy system considering generalized energy storage is proposed in this paper. In the first stage, a siting optimization submodel for the energy station and supply network in park-level integrated energy system is established to minimize the total comprehensive energy distance values from the energy station to all load stations, in which the virtual network flow theory is introduced to characterize and linearize the connectivity constraints of the supply network. Then, a sizing optimization submodel for the energy station and supply network in park-level integrated energy system is proposed in the second stage based on the optimal siting strategies of park-level integrated energy system, in which the generalized energy storage is considered to minimize planning costs and carbon emissions. Finally, case studies are conducted on an improved 55-bus park-level integrated energy system to verify the effectiveness of the proposed model, and simulation results demonstrate that the proposed model outperforms other existing planning models in terms of achieving lower total comprehensive energy distance values, total planning costs and carbon emissions. [ABSTRACT FROM AUTHOR]

[Display omitted] • MBBR inoculated with HN-AD bacteria was firstly employed in low-carbon wastewater. • 10.02 mg L-1h−1 TN removal rate was achieved aerobically at a C/N of 4. • Oligotrophic bacteria Thauera and Azoarcus played a key role at C/N ratio of 4. • NorB and NosZ played a significant role in reduction of nitrate to nitrogen gas. • Aerobic denitrification pathway of the system was NO 3 –-N → NO → N 2 O → N 2. To improve the poor denitrification efficiency of traditional biological treatment for low-carbon wastewater, a novel pure biofilm moving bed biofilm reactor (PH-MBBR) based on heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria was proposed. The start-up of PH-MBBR inoculated with HN-AD bacteria and the operating performances and microbial community composition under various C/N ratios were studied. The results showed that at C/N ratio of only 4, the total nitrogen (TN) removal rate of 10.02 mg/(L·h) was achieved under aerobic conditions. Microbial analysis indicates that the synergistic effect of oligotrophic bacteria Thauera and Azoarcus was the main reason for the high pollutant removal at C/N ratio of 4. Furthermore, the analysis of functional genes and enzymes reveals that NorB and NosZ played important roles in nitrate metabolism in PH-MBBR, and aerobic denitrification pathway was NO 3 –-N → NO → N 2 O → N 2. This study provides a practical and theoretical basis for low-carbon nitrate wastewater treatment. [ABSTRACT FROM AUTHOR]

Which countries best foster low-carbon electricity transitions – authoritarian regimes or democratic societies? Crucial for understanding how transitions unfold is identifying contextual factors conditioning propensity to adopt specific forms of energy production. This research assesses the relationship between quality of governance within 198 countries and domestic electricity production from all major energy sources, across the years 2002–2020. Governance quality is measured via a range of comprehensive, internationally recognised metrics, focusing predominantly on the World Bank's worldwide governance indicators. The data reveal that a future, decarbonised electricity system via wind, solar, and/or nuclear appears most likely in countries where the traditions and institutions by which authority is exercised support good governance. Over the last two decades, the association between electricity from solar and wind and good governance has progressively strengthened globally. Beyond governance, national measures of economic (in)equality are strongly related to electricity production from nuclear and hydropower. These findings offer a point of departure for assessing how governance systems might predispose countries to particular energy choices. [Display omitted] • The relationship between governance quality and electricity production is explored. • Includes 198 countries and electricity from solar, wind, hydro, nuclear, & fossil. • Good governance associates strongly and increasingly with wind and solar. • Good governance negatively associates with hydro and gas for electricity production. • Economic (in)equality is also related to electricity from nuclear and hydro. [ABSTRACT FROM AUTHOR]

Based on the need to reduce the carbon footprint of binders used for plant-based concretes, the development of lime–pozzolan binders is on the rise. The carbon emissions due to the binder production have to be reduced in such a way to ensure a high level of carbon storage while improving the thermal resistance of building envelopes. This paper intends to assess the technical feasibility of making plant-based concretes by mixing agricultural by-products (rapeseed straw, hemp and flax shives) with a binder composed of micronized marine sediment (non-calcined) and air lime. The hardening kinetics of the lime–sediment binder with sodium sulfate added was examined as a first step. The effect of various drying conditions on the strength development of lime–sediment mortars was then investigated to help understand the strength performances of plant-based concretes following 7 days of heat curing and 21 days at 65%RH. The results indicate that the newly formed solid products in the binder collected in plant-based concretes were mainly calcium carbonate and CO 3 -AFm. In spite of the low hydration degree of the binder, it was possible to reach an ultimate strength of 0.5─0.6 MPa at 7 % strain for a stabilized bulk density of 560 kg m−3. The rapeseed straw concrete was characterized by a strain hardening behavior due to the presence of tangled fiber-like particles and showed the lowest thermal conductivity (0.077 W m−1 K−1 in the dry state). • Sodium sulfate slightly improved the early age strength of the lime–sediment binder. • Plant-based concretes were subjected to heat curing for 7 days and 21 days at 65%RH. • Ultimate strength of about 0.5 MPa by mixing the new binder with plant aggregates. • Curing at 65%RH led to the strong formation of calcium carbonate and CO 3 ─AFm. • The lowest thermal conductivity was measured with the rapeseed straw concrete. [ABSTRACT FROM AUTHOR]

Synthetic nitrogen fertilizers such as urea are a necessity for food production, making them invaluable toward achieving global food security. Conventional manufacture of urea is conducted in centralized production plants at an enormous scale, with the subsequent prilled urea product distributed to the point-of-use. Despite consuming carbon dioxide in the synthesis, the overall process is carbon positive due to the use of fossil feedstocks, resulting in significant net emissions. Blue Urea could be produced using attenuated reaction conditions and hydrogen derived from renewable-powered electrolysis to produce a reduced-carbon alternative. This paper demonstrates the intensified production of urea and ammonium nitrate fertilizers from sustainable feedstocks, namely water, nitrogen, and carbon dioxide. Critically, the process can be scaled-down such that equipment can be housed in a standardized ISO container deployed at the point-of-use, delocalizing production and eliminating costs, and emissions associated with transportation. The urea and ammonium nitrate were synthesized in a semi-continuous process under considerably milder conditions to produce aqueous fertilizers suitable for direct soil application, eliminating the financial and energetic costs associated with drying and prilling. The composition of the fertilizers from this process were found to be free from contaminants, making them ideal for application. In growth studies, the synthesized urea and ammonium nitrate were applied under controlled conditions and found to perform comparably to a commercial fertilizer (Nitram). Crucially, both the synthesized fertilizers enhanced biomass growth, nitrogen uptake and leaf chlorophylls (even in depleted soils), strongly suggesting they would be effective toward improving crop yields and agricultural output. The Blue Urea concept is proposed for installation in ISO containers and deployment on farms, offering a turnkey solution for point-of-need production of nitrogen fertilizers.

The essence of low-carbon logistics is to make logistics capacity grow moderately to meet the requirements of social and economic developments and the goals of energy conservation and carbon reduction through logistics planning and policies, logistics rationalization and standardization, logistics informationization, low-carbon logistics technologies, etc. This study evaluates the performances of human resources in low-carbon logistics enterprises from three assessment facets: work ability, work performance, and work attitude. It adopts the AHP method to reasonably determine an indicator system of performance evaluation and its weight to avoid certain human-caused bias. According to the results herein, the low-carbon work attitude of the case company in recent years has produced good performance, but its low-carbon work performance and low-carbon work ability are both poor. The case company should practically implement and strengthen these indicators so as to enhance human resource performance in low-carbon logistics enterprises. This study establishes a human resources performance evaluation system for low-carbon logistics enterprises to measure the low-carbon working ability, work performance, and working attitude of their general staff. In this way, enterprises may understand their development status, improve development plans, and formulate the best human resources management and development decisions, thus positively guiding their future development. [ABSTRACT FROM AUTHOR]

Deep geothermal energy is widely recognised as a source of low carbon heat. However, to date there have been no specific assessment of the carbon intensity of low-enthalpy deep geothermal; previous studies focussed on geothermal power or higher enthalpy heat. As such, there is no established method for assessing the CO 2 emissions from implementing a deep geothermal heating scheme. Here we address these gaps. We perform a life cycle assessment of greenhouse gas emissions relating to a deep geothermal heat system to (i) calculate the carbon intensity of geothermal heat; (ii) identify key factors affecting these values; (iii) consider the carbon abated if geothermal heat substitutes conventional heating; and (iv) present information that future projects can apply to assess the carbon emissions reduction offered by geothermal heat development. Our work is informed by parameters from a feasibility study for a proposed geothermal heat system in Banchory, Scotland. The project planned a 2.5 MW th geothermal plant extracting heat from the Hill of Fare granite via two boreholes, one injection and one production. We find that the majority of the emissions are associated with site construction, and sensitive to site and materials specific factors, for example the depth of the drilled boreholes and type and quantities of steel and cement used to seal them, or soils disturbed for laying pipelines and constructing access roads. During operation the carbon intensity of the electricity grid used to power hydraulic pumps largely determines the carbon intensity of the produced heat. We calculate that the carbon intensity of the heat produced is 9.7–14.0 kg(CO 2e) MWh th which is 4.9–7.3% of the emissions from heat from natural gas. These values are compatible with Scotland's plans for long term decarbonisation of heat in line with national emission reduction obligations and would likely be compatible with any country's decarbonisation goals. Unlabelled Image • The carbon intensity of deep geothermal heat has a lower bound of 9.7 kg(CO 2e) MWh th. • The carbon intensity of deep geothermal heat has an upper bound of 14.0 kg(CO 2e) MWh th. • Direct use geothermal heat has 7% of the emissions of gas-fired boilers. • Deep geothermal heat is compatible with carbon reduction targets for 2050. [ABSTRACT FROM AUTHOR]

The issue of disassembly line balancing and remanufacturing has become an increasingly hot topic recently. However, little research focusing on carbon dioxide reduction and resource utilization has been done in the field of disassembly line balancing. For the purpose of being environmentally friendly, the disassembly line balancing should aim at low carbon emission, low energy consumption and cost reduction during the disassembly process. Considering this, this study proposes a multi-objective disassembly line balancing fruit fly optimization algorithm (MDFOA) for the disassembly sequence of obsolete agricultural machinery considering low-carbon design. We try to optimize the disassembly line balancing model using the fruit fly optimization algorithm. To satisfy the stability of MDFOA, the olfactory operation is cross-operated, and the Pareto non-dominated sorting method is adopted in the visual operation stage. In order to avoid falling into local optimum, a global cooperation mechanism is added to screen individuals with different degrees of dissimilarity. An illustrative example of the disassembly line of corn harvester cutting table is provided in this work. Comparison between our proposed MDFOA and other four frequently-used algorithms is conducted in this work. The results show that our method performs better than other algorithms for the disassembly line balancing problem (DLBP), thus verifying the practicability and feasibility of it. In the end, 12 Pareto solutions are obtained through MDFOA and we evaluated and selected the most satisfactory solution among them using Fuzzy AHP, for the determination of the optimal disassembly sequence. [ABSTRACT FROM AUTHOR]

Multiple energy systems (MESs) bring different types of energy together and are able to improve energy utilization efficiency and promote the integration of renewable energy. The embedded carbon emission in MES is coupled among the energy flow across different energy systems. The understanding of how the embedded carbon emission should be allocated along with the energy delivery and conversion is significant in the policy making and market design to facilitate carbon emission reduction. A novel analytical model for carbon emission flow (CEF) in MES is proposed in this paper to quantify the carbon emission associated with the energy delivery and conversion process. First, key indicators and basic principles of CEF are defined. Then, the explicit CEF models for different energy networks, including the power network, gas network and heating network, are established. On the basis of the CEF models of energy converters, the CEF model for an energy hub is further formulated to analyze the flow of carbon emission across different energy systems during the conversion process. Finally, the procedure of CEF calculation in MES is provided. The case study results based on two systems are presented to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Traditional coal mining and utilisation patterns are severely detrimental to natural resources and environments and significantly impede safe, low-carbon, clean, and sustainable utilisation of coal resources. Based on the idea of in situ fluidized coal mining that aims to transform solid coal into liquid or gas and transports the fluidized resources to the ground to ensure safe mining and low-carbon and clean utilisation, in this study, we report on a novel in situ unmanned automatic mining method. This includes a flexible, earthworm-like unmanned automatic mining machine (UAMM) and a coal mine layout for in situ fluidized coal mining suitable for the UAMM. The technological and economic advantages and the carbon emission reduction of the UAMM-based in situ fluidized mining in contrast to traditional mining technologies are evaluated as well. The development trends and possible challenges to this design are also discussed. It is estimated that the proposed method costs approximately 49% of traditional coal mining costs. The UAMM-based in situ fluidized mining and transformation method will reduce CO2 emissions by at least 94.9% compared to traditional coal mining and utilisation methods. The proposed approach is expected to achieve safe and environmentally friendly coal mining as well as low-carbon and clean utilisation of coal. [ABSTRACT FROM AUTHOR]

Abstract Low-carbon power dispatching with wind power has been attracting increasing attention recently, whereas it also encounters some difficulties under carbon trading mechanism, such as the resistance to carbon emission reduction, the fairness of carbon trading, and the disturbance of wind power uncertainty. For harmonizing these contradictions, this paper presents a stochastic dynamic economic dispatch model focusing on wind power uncertainty and carbon emission rights simultaneously, which tries to minimize total electrical energy costs under uncertainty, and to meet the specific requirement of carbon emission reductions. Moreover, several traditional allocation methods for initial carbon emission rights emphasizing the equality are introduced, and the uncertainty characterizations of wind power are discussed through the scenario-generation technique. The simulation results eventually demonstrate that the operating cost for non-cooperative mode cannot be optimized as the ratio of carbon emission reductions rises; carbon trading mechanism is beneficial for lower cost under the pressure of carbon emission reduction; carbon price ranges that suit both carbon trading parties could be deduced. Synthesizing wind power uncertainty and carbon emission rights, this study is helpful for allocating the load demand of wind power integrated system to each generating unit more scientifically and reasonably based on carbon trading mechanism. Highlights • A stochastic DED model is proposed for low-carbon power dispatching problem. • Carbon trading mechanism proved to be helpful for carbon emission reduction. • Carbon price ranges that suit both carbon trading parties are finally deduced. [ABSTRACT FROM AUTHOR]

Abstract Renewable energy is expected to gain a larger share in the Indonesian energy mix by 2025. Biogas has not only the potential to contribute significantly to the country's renewable energy targets by mid-century, but also to provide a series of co-benefits to improve wellbeing of vulnerable rural communities. The challenge is to find pathways for biogas to overcome well-established technologies and practices in the current heavily fossil fuel based energy system. This paper focused on household-level biogas development in Bali, Indonesia, critically analysing four domestic biogas programmes that are currently under implementation. For our analysis, we adopted an integrated approach combining the multi-level perspective framework with a system-mapping exercise. Moreover, a series of semi-structured interviews as well as an interactive workshop was conducted which allowed us to place multiple stakeholder perspectives and experiences at the heart of the analysis to look at factors beyond the micro-system of the technology, and understand the broader socio-institutional context. Our analysis of enabling and hindering factors to biogas expansion identified opportunities for improving the design and implementation of policy, finance and technology measures. These findings are relevant not only for the Indonesian context, but also for other developing countries that are increasingly investing in transitioning to low-carbon energy futures. Highlights • Barriers to biogas adoption mainly found in policy sector, access to finance and capacity building. • Overcoming barriers is possible by improving steps in market chain and with right policies. • Focusing on co-benefits, creating ownership and build capacity amongst adopters will be crucial. [ABSTRACT FROM AUTHOR]

Highlights • Ethiopia's sustainable industrial transition experiment could become a model for other African countries. • Green transition is sought by articulating pressure from global decarbonisation agenda as opportunity for economic growth. • With industrial clustering and eco-industrial parks, Ethiopia is taking significant steps down a low-carbon pathway. • Strong political will is yielding progress, but limited human and financial resources remain a formidable challenge. • The institutional framework for coordinating a sustainable industrial transition needs to be strengthened further. Abstract The concept of 'sustainable industrialisation' is now integral to the UN's Sustainable Development Goals. However, there are no historical examples or current models to emulate. Scholarly analyses of putative initiatives to green industrialisation, especially in developing countries, are few and limited. This article explores the conception and implementation of green industrialisation in Ethiopia, one of the world's poorest nations, where an ambitious Climate Resilient Green Economy (CRGE) strategy has been created, alongside a multi-sectoral Growth and Transformation Plan (GTP), to leapfrog environmentally unsustainable development and bring the country to middle-income status by 2025. Using the socio-technical transition (STT) perspective and in particular Smith, Stirling, and Berkhout (2005) framework for assessing sustainable transition programmes, it analyzes the 'selection pressures' on the industrial 'regime' and its 'adaptive capacity'. It finds: (i) clear articulation of the imperative for climate change mitigation and economic growth; (ii) strong high-level government commitment to a greening agenda within the context of accelerated industrialisation; and (iii) a nascent innovation system that is beginning to evolve according to these priorities. However, the analysis also identifies important challenges, including: coordination mechanisms between different stakeholders; framing issues; availability of resources; and ongoing tension between addressing climate change and promoting economic growth. It also highlights the importance of the availability of cross-border resources for purposive sustainability transition within low-income countries. [ABSTRACT FROM AUTHOR]

Abstract Ground source heat pump (GSHP) systems are energy-efficient technologies to provide low-carbon heating and cooling demands for the buildings. However, deployment of the GSHP systems in Japan is limited mainly due to the relatively high drilling costs for placement of the ground heat exchangers (GHEs), in comparison with EU and North American countries. This study is providing the historical data of deployment of different types of the GSHP systems in Japan, the supportive public policies and incentives for installation of GSHP systems. Finally, the barriers for the further utilization of the GSHP systems in Japanese buildings are discussed and solutions are suggested. [ABSTRACT FROM AUTHOR]