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In this paper an approach for analysing the potential for implementation of different technology pathways for the European pulp and paper industry (PPI) is presented. The approach is based on detailed technical research and aggregates the knowledge from previous studies to incorporate the whole European PPI. Thus, the potential for different technology pathways can be estimated on a European level whilst still considering important characteristics of individual mills. The usefulness of the approach was exemplified by applying it to a case study of the potential for introduction of carbon capture and storage (CCS) within the European PPI. The results from the case study show that for the European PPI, CCS has an up-hill road in order to be a viable, large scale alternative for reduction of CO2 emissions. If CCS is to be introduced in large scale within the European PPI, large biomass-based point sources of CO2 emissions need to be included when planning for CCS infrastructure and also the infrastructure needs to be built out for clusters emitting <20 MtCO2/yr. [ABSTRACT FROM AUTHOR]

Abstract: This paper evaluates system aspects of biorefineries based on biomass gasification integrated with pulp and paper production. As a case the Billerud Karlsborg mill is used. Two biomass gasification concepts are considered: BIGDME (biomass integrated gasification dimethyl ether production) and BIGCC (biomass integrated gasification combined cycle). The systems analysis is made with respect to economic performance, global CO2 emissions and primary energy use. As reference cases, BIGDME and BIGCC integrated with district heating are considered. Biomass gasification is shown to be potentially profitable for the mill. The results are highly dependent on assumed energy market parameters, particularly policy support. With strong policies promoting biofuels or renewable electricity, the calculated opportunity to invest in a gasification-based biorefinery exceeds investment cost estimates from the literature. When integrated with district heating the BIGDME case performs better than the BIGCC case, which shows high sensitivity to heat price and annual operating time. The BIGCC cases show potential to contribute to decreased global CO2 emissions and energy use, which the BIGDME cases do not, mainly due to high biomass demand. As biomass is a limited resource, increased biomass use due to investments in gasification plants will lead to increased use of fossil fuels elsewhere in the system. [Copyright &y& Elsevier]

Abstract: Hydrogen produced from renewable biofuel is both clean and CO2 neutral. This paper evaluates energy and net CO2 emissions consequences of integration of hydrogen production from gasified black liquor in a chemical pulp mill. A model of hydrogen production from gasified black liquor was developed and integration possibilities with the pulp mill''s energy system were evaluated in order to maximize energy recovery. The potential hydrogen production is 59000 tonnes per year if integrated with the KAM reference market pulp mill producing 630000 Air dried tonnes (ADt) pulp/year. Changes of net CO2 emissions associated with modified mill electric power balance, biofuel import and end usage of the produced hydrogen are presented and compared with other uses of gasified black liquor such as electricity production and methanol production. Hydrogen production will result in the greatest reduction of net CO2 emissions and could reduce the Swedish CO2 emissions by 8% if implemented in all chemical market pulp mills. The associated increases of biofuel and electric power consumption are 5% and 1.7%, respectively. [Copyright &y& Elsevier]

As a major institutional innovation of China's environmental governance system, weather the Central Environmental Protection Inspection (CEPI) can reduce carbon intensity is still unclear. This research takes 18,728 company-year sample observations of Chinese industrial A-share listed companies from 2009 to 2020 as the research object (CSMAR and CNRDS databases are used). Multi-period Differences-in-Differences model approach is employed to investigate the mechanisms through which the CEPI affects carbon intensity governance in industrial enterprises, the heterogeneous effects of CEPI are explored at macro, meso and micro levels. CEPI reduces the carbon dioxide emissions of industrial enterprises by 0.028 tons per 10,000 yuan of output value, CEPI achieves carbon intensity governance effect by incentivizing companies to enhance the quantity and the quality of green technological innovation. High level of public environmental oversight and industry competition, as well as nature of state-owned enterprises facilitate the CEPI's role in promoting the reduction of enterprise carbon intensity. The findings provide practical insights for driving green technological innovation among enterprises. Some policy implications are proposed. CEPI should be regulated to strengthen the environmental governance responsibilities of local governments and incentivize industrial enterprises to improve the quantity and quality of green technological innovation and reduce carbon intensity. [Display omitted] • Pioneering CEPI's research on the governance of carbon intensity of industrial enterprises. • A mediation model is introduced to analyze the governance pathway of CEPI policy. • Examining CEPI's impact on both the quantity and quality of green technology innovation. • In this paper we conduct heterogeneous analyses at macro, meso, and micro levels. [ABSTRACT FROM AUTHOR]

For energy conservation, emission reduction and sustainable development, China launched the New Energy Demonstration City Program (NEDC) to try a more decentralized energy governance structure. Based on the theoretical framework between NEDC and carbon emissions, this paper tests its policy impact and mechanism. The results show that NEDC can significantly reduce carbon emissions by about 15.34%. The policy effects of NEDC are characterized by time lag and increasing intensification. NEDC has a stronger effect on reducing carbon emissions in western cities and non-resource-based cities. NEDC can reduce carbon emissions through industrial structure effect, environmental decentralization and information technology effect. NEDC has a synergistic emission reduction effect, which can reduce about 20.39% of nitrogen oxides (NOx) and 18.70% of sulfur dioxide (SO 2). NEDC has policy spillover effect, which can not only reduce the carbon emissions of pilot cities, but also reduce the carbon emissions of neighbouring cities. The space emission reduction effect of NEDC is better within 400 km. Finally, this paper puts forward policy recommendations to strengthen decentralized energy governance to reduce carbon emissions. • NEDC can reduce carbon emissions, which has the characteristics of hysteresis. • Central cities and non-resource-based cities have greater policy effects. • Industry, environmental decentralization, and technology are policy paths. • NEDC has synergistic emission reduction effect, which can reduce NOx and SO 2. • NEDC has spillover effect when the distance is not more than 400 km. [ABSTRACT FROM AUTHOR]

Taking the regional production restriction policy in the Beijing-Tianjin-Hebei region and surrounding areas (BTH2+26) -- Chinese off-peak production (COPP) policy in heating season from 2017 -- as a quasi-natural experiment, this paper adopts the DID method to explore how the COPP policy impacts firms' green transition from the dual perspective of pollutant emissions reduction and efficiency gains and its internal mechanism. The results show that: (1) The COPP policy can significantly reduce air pollutant emissions without decreasing the TFP of Chinese heavy-polluting listed companies in BTH2+26. (2) Mechanism analysis find that the COPP policy can achieve firms' green transition that combined emission reduction and efficiency gains, which is due to the promotion effect of technological innovation activities and the reduction effect of environmental costs. (3) Further analysis shows that the COPP policy on the innovation output ability of Chinese heavy-polluting companies in BTH2+26 is greater than that on the innovation input ability. (4) Heterogeneity analysis shows that the COPP policy has a more significant promoting effect on the green transition of private enterprises. Our paper can provide empirical evidence and policy recommendation for the Chinese government to promote pollution control in specific regions. • The COPP significantly reduces pollution without reducing the productivity of Chinese heavy-polluting enterprises. • The COPP affects the innovation output ability of Chinese heavy-polluting enterprises is greater than input. • The COPP mainly affects the TFP of enterprises by promoting green innovation and improving environmental cost efficiency. • The COPP can promote the TFP of non-state-owned enterprises more than that of state-owned enterprises. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the co-movement and dependence structure between China's emissions allowances (CEA) and wholesale diesel (gasoline) markets using a GARCH-copula with a generalized error distribution (GED). Chinese emissions allowances prices exhibit significantly extreme co-movement with wholesale diesel and gasoline prices using GARCH and TARCH models based on a GED. The empirical results confirm that different markets except Hubei's emissions-gasoline market exhibit a greater divergence of asymmetric tail dependence structure between emissions allowances and wholesale diesel (gasoline) markets. Beijing's emissions allowances prices show an asymmetric mixture of right-tail and left-tail dependence structures with wholesale diesel and gasoline prices in northern China, implying stronger right-tail dependence. Shanghai and Guangdong's emissions allowances prices indicate a significant right-tail dependence structure with wholesale diesel and gasoline prices in East and South China. Hubei's emissions allowances prices exhibit an asymmetric mixture of right-tail and left-tail dependence structures with wholesale diesel prices, implying stronger left-tail dependence and a significantly symmetric dependence structure with wholesale gasoline prices in central China. Highlights • This paper presents the mixed copula-GARCH model based on GED. • We examine the co-movement between emissions allowances and fuel markets. • Different markets exhibit significant and asymmetric tail dependence structure. • Most of emissions-fuel markets exhibit a positive dependence. [ABSTRACT FROM AUTHOR]

Human activities have led to increase in carbon dioxide emissions, and carbon tax is one of the main policy tools for reducing global emissions. This paper constructs nine scenarios considering different carbon tax rates and the different taxable industries to analyze the impact of Carbon Tax System (CTS) on energy, environment and the economy. We find that the negative impact of CTS on GDP is acceptable, and the maximum scenario will not exceed 0.5%. If carbon taxes are levied on energy-intensive enterprises, the impact on carbon emissions is also relatively small, even if the carbon tax rate is relatively high. Higher carbon tax rate will result in higher CO 2 emission reduction and higher marginal CO 2 emission reduction of CTS. The carbon tax rate follows the "law of increasing marginal emission reduction". We also argue that the focus of taxation should be on energy enterprises. It is only in this way that the efficiency of the energy market can be fully implemented to conserve energy and reduce emissions. This paper suggests that China should adopt CTS that simultaneously imposes a higher tax on energy companies and energy-intensive enterprises. This will maximize emissions reductions and have only a small impact on GDP. [ABSTRACT FROM AUTHOR]

Physics-based model has been regarded as a promising alternative to equivalent circuit model due to its ability to describe internal electrochemical states of battery. However, the rigorous physics-based model, namely pseudo-two-dimensional (P2D) model, is too complicated for online application in embedded battery management system. In this paper, to simplify the P2D model, a series of polynomial functions are employed to approximate the electrolyte phase concentration profile, solid phase concentration profile, and non-uniform reaction flux profile, respectively. Especially, the accuracy of 2nd-order and 3rd-order polynomial approximations for reaction flux is compared, and the higher-order is validated with more strength. Benefit from the acquisition of above variables, the electrolyte potential is derived directly according to the conservation of charge at electrolyte phase; the accuracy of activation overpotential is also improved by using the non-uniform reaction flux rather than assuming the uniform current density in single particle (SP) model. Finally, the developed model is simulated by different constant current rates, hybrid pulse and driving cycles, and its outputs are compared with P2D model and original SP model. The results demonstrate that the model proposed in this paper could capture the battery characteristics efficiently, and also significantly reduce the computation complexity. [ABSTRACT FROM AUTHOR]

Both environmental regulation (ER) and different pollutants emission are characterized by differentiation, but the nonlinear relationship between different intensities of ER and different levels of pollutants emission has not yet been elaborated. This paper examines the nonlinear effects of ER at different intensities on PM 2.5 and CO 2 at different states with the help of cutting-edge Quantile on Quantile Approach (QQA), comprehensively reveals the inner law of ER to promote pollutants synergistic reduction. This study found that, both PM 2.5 and CO 2 show obvious regional differences but are not polarized. ER can effectively help reduce PM 2.5 and CO 2 in average, and this reduction effect is more obvious for central-western cities. The effects of different intensities of ER on different states of PM 2.5 and CO 2 have obvious nonlinear spillover characteristics. The impact of ER on PM 2.5 shows wave-like changes. Increasing ER intensity has a stronger inhibitory effect on PM 2.5 of high scale, but when PM 2.5 is relatively low, moderate ER is needed to match it, and excessive intensity of ER will be detrimental to reduce PM 2.5. The negative impact of ER on CO 2 fluctuates relatively stable. ER at high quantiles have more obvious reduction effect on CO 2 of high levels, but excessive intensity of ER is not conducive to reduce CO 2. Achieve the synergistic reduction of PM 2.5 and CO 2 should not only consider the differences in ER between regions, but also to combine the scale differences of pollution and carbon emission. Our study suggests that the improvement of synergistic emission reduction system needs to consider the strength of ER and the level of pollutants emission according to local conditions, which will help to realize green development more efficiently. • Assessing the impacts of different intensities of ER on different levels of PM 2.5 and CO 2. • The use of QQ approach can obtain richer nonlinear information. • The effects of ER on PM 2.5 and CO 2 are asymmetric and heterogeneous. • Increasing ER intensity has a stronger inhibitory effect on PM 2.5 of high scale. • Nonlinear changes in the negative impact of ER on CO2 fluctuates relatively stable. [ABSTRACT FROM AUTHOR]

M-TES (Mobile Thermal Energy Storage) technology is explored in this paper for transportation of industrial surplus heat for use in LTDH (low temperature district heating network). LTDH has promising potential in utilizing low grade heat, on the other hand, 20%–50% of industry generated surplus heat is often released to the ambient environment. M-TES is used to match thermal energy supply and demand that occur at different locations and that are shifted in time. In this paper, design of M-TES is conducted, optimization in operating strategies is performed, sensitivity analysis on levelized cost is studied, and environmental impact of CO 2 emissions due to transportation is evaluated. The results of the study show an array of transportation means and storage operating strategies under which M-TES is technically, economically and environmentally sound for transportation of industrial surplus heat for use in LTDH network. [ABSTRACT FROM AUTHOR]

In China, industrial sectors contribute carbon emissions at a larger scale and more rapidly growing pace than other end-use sectors. This paper thus aims to investigate the dynamic carbon emissions performance of China's industrial sectors using Malmquist-type index. Previous studies suffer from two limitations: the challenge of isolating carbon emissions performance from radial efficiency measures and the infeasibility problem in the calculation process. This paper proposes the non-radial global Malmquist carbon emissions performance index (NGMCPI) as a way of handling those two challenges with measuring dynamic changes in carbon emissions performance. The NGMCPI can be decomposed into efficiency change (EC) and technological change (TC) indexes, which represent the low-carbon catch-up and innovation effects, respectively. Based on the proposed indexes, we examine the dynamic changes in carbon emissions performance and its patterns for 38 Chinese industrial sectors over the 1990–2012 period. The results show that dynamic carbon emissions performance was mainly driven by the catch-up effect during the 1990s and boosted by innovation from 2000 to 2012. Some policy implications are proposed based on these empirical results. [ABSTRACT FROM AUTHOR]

Currently, most of the performance analysis and optimization design of the gas turbine combined cycle (GTCC) units ignore the economic loss to the environment caused by the pollutant emissions. In this paper, based on the structure theory of thermoeconomics, an environmental thermoeconomic cost model is established. And then an annual total cost model is established, which can reflect the real economic performance. Based on the comprehensive analysis of the energy, economy and environment, with the objectives of the higher exergy efficiency, less annual total cost and lower specific CO 2 emission rate, a multi-objective optimization study of the GTCC unit is conducted using the genetic algorithm (GA) in this paper. Pareto frontiers for the multi-objective optimization has been obtained with GA, and in turn a design plan can be selected from the Pareto frontier according to the preference. The multi-objective optimization results show that the optimized system can greatly increase the system environmental thermoeconomic performance. Moreover, the effects of main variables on the economic performance index of the optimized system are investigated. The results show that the natural gas price has the greater impact on the economic performance index compared with the pollutants environmental damage cost and the non-energy cost. • Multi-objective optimization model of GTCC system considering environment damage cost is built. • Multi-objective optimization of GTCC system considering environmental cost is studied. • Comprehensive analysis of energy, economic and environmental (3E) benefits is conducted. • Effects of main variables on economic performance index of the optimized system are revealed. [ABSTRACT FROM AUTHOR]

Future energy systems need to synthesize a mix of solutions to reduce energy spending and CO 2 emissions. The NZEXD (net-zero exergy district) target can guide districts in better using the useful work potential (exergy) of energy resources. This paper develops a four step analysis approach to bring districts closer to two net-zero targets: NZEXD and NZCED (net-zero compound CO 2 emissions district). Step 1 requires the modeling of the initial net-zero exergy status. Step 2 involves the modeling of the exergy matches in the district and its compound CO 2 emissions in the energy system. Step 3 considers scenarios based on the decision-making tools of the REMM (Rational Exergy Management Model) Analysis Tool and a multi-criteria index. Step 4 finalizes the approach based on the selection of a scenario to start implementation. The four steps are applied to the second phase of Östra Sala backe in Uppsala, Sweden that will host 20,000 people by 2030. The paper concludes with a proposal for the second phase. The energy system configuration has an energy load of 88.4 GWh, NZEXD status of 1.8 GWh, and NZCED status of −7.6 Gton. The results are useful for IEA (International Energy Agency) Annex 64 and assisting local decision-makers to integrate exergy into energy plans to support an exergy transition. [ABSTRACT FROM AUTHOR]

Over the past decades, China's vast regional disparities in resource endowment, economic development, and industrial structure have driven large-scale relocations of high energy-consuming industries (RHEIs). Despite extensive research on broad-based industrial relocation and emission transfer, the trend, structure and environmental impact of China's RHEIs need further investigation. This paper employs the multi-regional input-output model (MRIO) to calculate the trend, scale, and structure of the RHEIs among China's 30 provinces. Additionally, we investigate the RHEIs' effect on green total factor energy efficiency (GEE) and its heterogeneity. Our results indicate that the net inflow of high energy-consuming industries decreases GEE, with a more noticeable effect observed in central provinces and after the execution of the Belt and Road Initiative (BRI). However, the positive effect of RHEIs on GEE in outflow areas is more substantial than their negative impact in inflow areas, suggesting that RHEIs can enhance overall efficiency. This study contributes to the understanding of China's industrial relocation by providing valuable insights into China's RHEIs. • China has a large-scale relocation of high energy-consuming industries. • The relocation of China's high energy-consuming industries is calculated. • The relocation's impact on green total factor energy efficiency is analyzed. • Regional heterogeneity is found among different provinces. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are playing a key role in supporting transportation electrification and reducing air pollution and greenhouse gas emissions. The increased number of EVs may also bring about some issues concerning energy system structure optimization and efficiency enhancement. User behavior analysis and simulation is an important method to solve these issues. A stochastic model for describing the usage of vehicle is essential to handle simulation models and behavior models. Therefore, a more comprehensive understanding of EV usage patterns is necessary for the model establishment. The paper focuses on the 2,047,222 charging events and 8,382,032 travel events collected from 26,606 battery electric vehicles operating in Beijing, China, in 2018, based on the open lab of National Big Data Alliance of New Energy Vehicles. With the large-scale data resource rather than limited samples, we provide some robust statistical results and some multi-dimensional comparative analysis in the paper, which can be applied in large-scale deployment environments and large population cities. The results can also provide information for charging infrastructures construction, gird management, vehicle charging scheduling, and so forth in Beijing and even other metropolises with similar situations. • Operational data of 26,606 battery electric vehicles in Beijing are collected. • The usage pattern including charging pattern and travel pattern is investigated. • Probability density function is used to analyze usage pattern characteristics. • The characteristics of vehicles in different application scenarios are compared. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents high renewable electricity penetration scenarios in the United States using detailed capacity expansion modeling that is designed to properly account for the variability and uncertainty of wind and solar resources. The scenarios focus solely on the electricity system, an important sector within the larger energy sector, and demonstrate long-term visions of a U.S. power system where renewable technologies, including biomass, geothermal, hydropower, solar, and wind, contribute 80% of 2050 annual electricity, including 49–55% from wind and solar photovoltaic generation. We present the integration challenges of achieving this high penetration and characterize the options to increase grid flexibility to manage variability. Four high renewable pathways are modeled and demonstrate the robustness and diversity of renewable options. We estimate 69–82% annual greenhouse gas emission reductions and 3%–30% incremental electricity price increases associated with reaching 80%-by-2050 renewable electricity relative to reference scenarios. This paper affirms and strengthens similar analysis from the Renewable Electricity Futures study by using an improved model and updated data to better reflect investment and dispatch decisions under current outlooks for the U.S. electricity sector. [Copyright &y& Elsevier]

In order to optimize the economic dispatching of the electric power system, this paper has proposed a new Hybrid Intelligent Algorithm based on the Particle Swarm Optimization (PSO) and Artificial Fish Swarm Algorithm (AFSA). Basing on a comprehensive dispatching optimization model with the goal of minimizing coal consumption, pollution emission and purchasing cost, we have utilized this Hybrid Intelligent Algorithms to solve the integrated weighted dispatching optimization model for five units and ten units respectively, considering the node flow balance of the power system, as well as the system's active power balance, positive and negative reserve constraints, transmission capacity constraints, unit output constraints, node voltage constraints, unit output power rise rate constraints, unit minimum runtime and downtime constraints, etc. The calculation results in the case study of five units are that coal consumption is 10,074.17 hundred-yuan, carbon emission is 11,280.75 kg, and electric power cost is 12,827.54 hundred-yuan. The calculation results in the case study of ten units, given a population size of 200, are that coal consumption is 31,305.45 hundred-yuan, carbon emission is 13,982.06 kg, and electric power cost is 16,754.79 hundred-yuan; while given a population size of 30, coal consumption is 29,221.16 hundred-yuan, carbon emission is 10,921.21 kg, and electric power cost is 16,521.56 hundred-yuan. Moreover, we have obtained the above results with an improvement of 35.56% in calculation efficiency. • An optimization model minimizing coal input, emission and cost was constructed. • A Hybrid Intelligent Algorithm based on the PSO and AFSA Algorithm was designed. • The calculation efficiency of two cases was improved 35.56% by the new algorithm. • The suitable range of population size for this new algorithm was determined. [ABSTRACT FROM AUTHOR]

Distributed energy systems (DESs) are becoming increasingly popular because of their high-energy efficiency and low pollution emissions. Accurate performance evaluation of such systems is critical for processes at the early design stages. However, there are considerable uncertainties in terms of the parameters used for performance evaluation and design optimization, including component efficiencies, customer demands, and energy markets. These uncertainties can significantly influence the performance of DESs. Without consideration of these uncertainties, the performance of DESs can be overestimated or underestimated, which leads to inaccurate decision-making. Therefore, this paper presents a comprehensive evaluation of the performance of DESs by considering uncertainties in 12 parameters that relate to the electrical and thermal efficiencies of generators, efficiency of chillers and pumps, load density, energy markets, and so on. The energy and economic performance of DESs under each uncertainty are analyzed and compared with that of conventional energy systems. The suitable conditions for using DESs and other factors that can influence their performance are determined. The results of this study can serve as a guide for design optimization and policy development to promote the use of DESs in China. • Uncertainties affecting the performance of DESs compared with CES are investigated. • Impacts of 12 parameter uncertainties on the performance of DESs are quantified. • Four control methods are implemented and compared. • Suitable conditions, influential factors and suggestions to promote DESs are obtained. • The control method following the cooling demand is preferred. [ABSTRACT FROM AUTHOR]

Abstract Bio-oils have been known with some advantages such as biodegradability, renewable, oxygen content, no-sulfur content. However, high viscosity, high surface tension and density due to the large structure may be the main causes strongly affecting the spray characteristics, mixture formation, combustion process, and emission characteristics of diesel engines running on bio-oils. In this work, the evaluation of the relationship between the spray parameters of used bio-oils including spray penetration (S) and cone angle (ɸ), and preheating temperature compared to fossil diesel fuel was conducted. Besides, the influence of the spray parameters on the breakup mechanism, brake thermal efficiency (η e), heat release rate (HRR), and emission characteristics of an 80hp-diesel engine was reported. As a result, pure bio-oil was preheated to 105 °C to achieve the similarity of some physical properties and spray parameters compared to diesel fuel, but emission parameters of carbon monoxide (CO) and unburnt hydrocarbon (UHC) were 23.10% and 23.36% respectively higher. Meanwhile, brake thermal efficiency (η e), and emissions of CO 2 , NOx, smoke were 3.36%, and 12.00%, 8.86%, 48.48% respectively lower than those of fossil diesel fuel. The findings in this paper showed further evidence in the direct use of pure biodiesel as a fuel for diesel engines. Highlights • The heating method is used to improve the disadvantages of bio-oils. • Spray characteristics of preheated bio-oils to 80–110 °C are determined. • Engine performance and exhaust gas temperature are measured and analyzed. • The optimum heating temperature for as-used bio-oils is 105 °C. • An exhaust gas-electricity integration system is fabricated for experimental purpose. [ABSTRACT FROM AUTHOR]

Abstract In this study effects of compression ratio on HCCI combustion, performance and emissions was investigated parametrically. In addition to parametric investigation and as a novel way of the paper engine BSFC maps were obtained for RON20 andRON40 fuels and each compression ratios of 9:1, 10:1, 11:1 and 12:1. The parametric experiments were carried out at 800 rpm engine speed. In both parametric and mapping experiments were conducted at intake temperature of 353 K. In-cylinder pressure, ROHR, combustion duration, start of combustion, indicated mean effective pressure, thermal efficiency and CO, HC and NO x emissions were examined. It was determined that in-cylinder pressure and rate of heat release decreased while the mixture getting leaner. The increase of octane number of fuel led to extension of combustion duration. On the contrary, combustion duration decreased along with the increase of compression ratio. It was found that the CO and HC emission were high while NO x emissions were low at lower CR. With the increase of CR, CO and HC emissions decreased however NO x emissions increased. The maximum thermal efficiency was obtained as 38.2% at 800 rpm and 12:1 CR with RON40 fuel. The widest operational region was obtained with RON20 fuel at CR of 10:1 with a minimum BSFC value of 210 g/kWh. Highlights • RON20 and RON40 fuels were tested in A HCCI engine at different compression ratios. • RON, lambda and compression ratio effects on HCCI engine was examined parametrically. • Additionally BSFC and operation maps were determined for each compression ratio. • RON40 seems more suitable fuel due to controlling the HCCI combustion in all compression ratios. • Largest operation map in terms of engine load and speed was obtained with RON20. [ABSTRACT FROM AUTHOR]

Abstract This paper presents the overall performance, emission and combustion characteristics of the engine, when fuelled with biodiesel blends of Calophyllum Inophyllum methyl ester as injected fuel and babul wood chip derived producer gas as inducted fuel at constant injection timing (230bTDC), injection pressure (230 bar) and speed (1500 rpm). To improve overall performance, combustion and reduced emission characteristics of the engine, the combustion chamber was varied with 5 different geometries. Experimental results revealed that Toroidal re-entrant combustion chamber had higher Exhaust Gas Temperature and Brake Thermal Efficiency by 20.75% and 6.37% than that of HCC, while Brake Specific Fuel Consumption was reduced by 4.49% at optimal loading condition. However, engine overall performance of TrCC was found to be comparable with Hemi-spherical chamber and other designed combustion chambers. Similarly, comparing exhaust emissions, Oxide of Nitrogen and Carbon dioxide were on its higher side by 19.90% and 27.20% than normal HCC. On the contrary, carbon monoxide, Hydrocarbon and Smoke opacity for TrCC were found to be 76.12%, 33.71% and 38.67% lower than HCC. From the above study, it is finally concluded that converted renewable fuels with TrCC might be utilized as an alternative fuel without any exhaust related problems. Highlights • CIME 20 showed better oil characteristics. • BTE for CIME 20-producer gas with TrCC was 6.37% higher than diesel HCC. • NO x emission for HCC-diesel was 19.9% lower than TrCC CIME20 P. gas. • CIME 20-producer gas with TrCC emits 33.71% and 38.67% less HC and smoke. • Diesel fuel savings of 80.5% for diesel-producer gas at optimal load condition. [ABSTRACT FROM AUTHOR]

Abstract This paper describes the application of Fuzzy Logic, Genetic Algorithm (GA) and Fuzzy Analytic Hierarchical Process-Technique for Order Preference by Similarity to Ideal Solution (FAHP-TOPSIS) for the selection of optimum blend from the various alternative blends of fish oil and diesel. A single cylinder, constant speed and direct injection diesel engine with a rated output of 4.4 kW is used for exploratory analysis at different load conditions. Ten parameterssuch as maximization of brake thermal efficiency, rate of pressure rise and minimization of NO x, CO 2 , CO, HC, smoke, exhaust gas temperature, ignition delay and combustion delay are considered. From the experimental data, multi input multi output (MIMO) fuzzy models are developed using triangular membership functionto predict the engine parameters. The developed model has good correlation with the observed data with noticeably low errors. Then, for each parameter, optimum blend has to be identified for all the loads using genetic algorithm which is a multi-objective optimization process. The engine performance is accurately predicted for the identified best load and blend from the developed fuzzy model. Hence in the proposed model, fuzzy logic is integrated with GAto find the best blend. Finally, from the best blend of each parameter, the exact biodiesel proportion of about 17% for no load, 17% for 25% load, 18% for 50% load, 17% for 75% load and 20% for 100% load are found out usingTOPSIS which will best suit the engine performance and reduction of emissions. Highlights • Analyzed the combustion characteristics of fish oil biodiesel. • Fuzzy-GA to predict the performance. • TOPSIS to evaluate the best blend. [ABSTRACT FROM AUTHOR]

Abstract: The way in which GHG (greenhouse gas) emissions associated with grid electricity consumption is handled in different LCA (life cycle assessment) studies, varies significantly. Apart from differences in actual research questions, methodological choices and data set selection have a significant impact on the outcomes. These inconsistencies result in difficulties to compare the findings of various LCA studies. This review paper explores the issue from a methodological point of view. The perspectives of ALCA (attributional life cycle assessment) and CLCA (consequential life cycle assessment) are reflected. Finally, the paper summarizes the key issues and provides suggestions on the way forward. The major challenge related to both of the LCA categories is to determine the GHG emissions of the power production technologies under consideration. Furthermore, the specific challenge in ALCA is to determine the appropriate electricity production mix, and in CLCA, to identify the marginal technologies affected and related consequences. Significant uncertainties are involved, particularly in future-related LCAs, and these should not be ignored. Harmonization of the methods and data sets for various purposes is suggested, acknowledging that selections might be subjective. [Copyright &y& Elsevier]

Abstract: The gaming and hospitality sector has been expanding rapidly in recent years. Concurrently energy consumption in this sector has surged significantly. This paper reviews the literature on the relationship between electricity consumption and economic growth and introduces the 4-parameter logistic functions to model the growth of electricity consumption and other related parameters in the world’s gaming center–Macao, China. The accuracy of the growth models were assessed by using the mean absolute percentage error and the root mean squared percentage error. The paper also introduces the application of life cycle analysis to greenhouse gases emissions for electricity consumption. As Macao in recent years has imported a significant amount of electricity from a coal-fired power plant in its nearby area – Zhuhai, the impact analysis included greenhouse gases emissions from the extraction, transportation, processing, and combustion along fuel life cycles in the local power plant as well as Zhuhai’s power plant. We found that the emissions associated with the imported electricity contributed greatly to total emissions. [Copyright &y& Elsevier]

Abstract: India’s aspiration for economic growth has consequences for energy growth and CO2 emissions. This paper examines India’s need for energy with 20 year perspectives. From an earlier paper by K. Parikh et al. (2009), demand scenario are examined from the supply perspectives ranging from coal, hydrocarbon, nuclear, hydrogen, hydro and other renewable etc. None of these are substantial and India will have to rely on imports. The need for energy has to be reduced by a drive for energy efficiency and renewable energy. Government programmes for the above are also commented upon. Though India’s CO2 emissions are unlikely to grow very much due to energy scarcity and energy mix the article examines the potential to reduce CO2 emissions and the associated costs involved in various options. It finds that 30% reduction in CO2 emissions by 2030 is feasible but would involve additional costs. The most promising option is to reduce energy demand by various measures to increase energy use efficiency in production and consumption. [Copyright &y& Elsevier]

Abstract: This construction industry is responsible for over 30% of the total industrial CO2 emission in Korea, and bearing wall apartment housing represents more than 50% of all housing in Korea. A new multi-residential Modularized Hybrid System (MHS) for construction of apartment housing may reduce the amounts of construction material used as well as the amounts of CO2 emission. This paper collected and compared data on the CO2 emission properties of construction materials for bearing wall and new MHS apartments including concrete, reinforcing steels, formwork, and gypsum board. MHS construction techniques reduce CO2 emission by 25.1% by requiring less concrete and reinforcing steels for slabs and walls that would otherwise be needed in conventional bearing wall structures. This paper also shows that migration to a Rahmen structure utilizing an MHS frame can provide an alternative solution to reducing CO2 emission. [Copyright &y& Elsevier]

Abstract: The demand for electricity in the Maldives continues to increase by more than 11% in recent years. This is mainly due to the growing number of high-rise air-conditioned buildings and the increasing use of electrical appliances in the residential and commercial sector. This paper investigates potential cost savings and emission reductions achieved by installing different insulation materials of optimum thickness in building''s walls. The paper also investigates the effect when air gaps are introduced in the wall. The optimum insulation thickness is based on the cost benefits of each insulation material over its lifetime. This study found that by introducing optimal thickness of different insulation materials and by having air gaps of 2 cm, 4 cm and 6 cm, energy consumption and emissions can be reduced by 65–77%, in comparison to a wall without insulation or air gaps. And, hence have considerable cost savings. [Copyright &y& Elsevier]

Abstract: One technology that seems to be promising for automobile pollution reduction is the Homogeneous Charge Compression Ignition (HCCI). This technology still faces auto-ignition and emission-control problems. This paper focuses on the emission problem, since it is incumbent to realize engines that pollute less. For this purpose, this paper presents results concerning the measurement of the emissions of CO, NO x , CO2, O2 and hydrocarbons. HCCI conditions are used, with equivalence ratios between 0.26 and 0.54, inlet temperatures of 70°C and 120°C and compression ratios of 10.2 and 13.5, with different fuel types: gasoline, gasoline surrogate, diesel, diesel surrogate and mixtures of n-heptane/toluene. The effect of dilution is considered for gasoline, while the effect of the equivalence ratio is considered for all the fuels. No significant amount of NO x has been measured. It appeared that the CO, O2 and hydrocarbon emissions were reduced by decreasing the toluene content of the fuel and by decreasing the dilution. The opposite holds for CO2. The reduction of the hydrocarbon emission appears to compete with the reduction of the CO2 emission. Diesel seemed to produce less CO and hydrocarbons than gasoline when auto-ignited. An example of emission reduction control is presented in this paper. [Copyright &y& Elsevier]

Abstract: The energy intensive industry can be a major contributor to CO2 emissions reduction, provided that appropriate investments are made. To assess profitability and net CO2 emissions reduction potential of such investments, predictions about future energy market conditions are needed. Energy market scenarios can be used to reflect different possible future energy market conditions. This paper presents a tool for creating consistent energy market scenarios adapted for evaluation of energy related investments in energy intensive industrial processes. Required user inputs include fossil fuel prices and costs associated with policy instruments, and the outputs are energy market prices and CO2 consequences of import/export of different energy streams (e.g. electric power and biomass fuel) from an industrial process site. The paper also presents four energy market scenarios for the medium-term future (i.e. around 2020) created using the tool. [Copyright &y& Elsevier]

Abstract: This editorial and overview of a Special Issue dedicated to the 11th Conference Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction – PRES 2008. Thirteen papers have been selected and after being peer-reviewed. Nine were accepted for publication covering important subjects of energy generation and usage. They are focusing on recent development of various features of heat integration which is an important methodology for increasing energy efficiency and saving. The complementary issues covered are emissions reduction and the security of energy supply. This issue of ENERGY is the fourth special journal issue dedicated to selected papers from PRES conferences. [Copyright &y& Elsevier]

Abstract: The paper deals with waste gasification as a technology allowing for indirect co-firing of large quantities of biodegradable wastes in coal-fired power boilers. In contrast to common landfilling and direct co-firing, gasification of wastes presents a number of advantages. Problematic species in original feedstocks can be partly safely incinerated in the furnace and partly retained in the gasification residues. The paper focuses on the impact of indirect co-firing on basic boiler parameters and performance. The work carried out was in the form of a case study for co-firing LCV gas in a 230t/h dual fuel pulverized coal-gas fired boiler. Thermal shares of 10, 20 and 40% have been investigated for two extreme LCV gas qualities represented in the calculations by its calorific value of 2.0 and 8.5MJ/m3 n respectively, thus six calculation cases are given. The results of the study reveal that even high thermal shares of LCV gas may be achieved for co-firing of better quality gas without significant effects on boiler operation. For lower quality gas, even a 10% thermal share influenced boiler operation to a great extent. This paper also gives consideration in relation to avoided CO2 emissions accomplished via indirect co-firing. [Copyright &y& Elsevier]

Abstract: This paper provides an overview of the evolving climate-change strategies put in place by industrialized countries to combat climate change and to comply with their quantitative commitments under the Kyoto Protocol. It links past policy performance with the historical level of greenhouse-gas emissions and with indicators of policy performance, such as energy intensity and carbon intensity, between 1990 and 2000. It presents the emerging new and integrated method of climate-policy formulation and implementation based on a portfolio approach, where a mix of policies and measures are selected to help achieve the required emissions reduction. The paper outlines the portfolios of policy instruments used by the industrialized countries in their evolving climate-change strategies and in their approach to widening the scope and increasing the coverage of those policy instruments to all sectors and all gases. [Copyright &y& Elsevier]

To achieve low-NO x emission in the coal-fired industrial boiler, the radial air staging method is proposed. The location of the over-fired air (OFA) is an essential parameter as it affects the combustion stability, NO x generation, burnout, and slagging trend. These are related to the gas-particle flow such as the recirculation region, gas mixture, and gas-particle mixture. Therefore, in this paper, taking a coal-fired industrial boiler with radial air staging method as an object, in a cold-modeling furnace, the gas-particle flow characteristics under various OFA locations (L D of 1.29, 1.43, 1.72, and 2.00) are studied. When OFA is radially arranged, the OFA jet diffuses towards the furnace center. As the L D increases, the size of the central recirculation region increases, thereby improving combustion stability. When the L D is 2.00, the mixing of the OFA jet and PCC jet obviously is delayed. Moreover, an increase in L D leads to more returned particles in the furnace center, promoting the reduction reaction of NO x. In addition, as the L D increases from 1.29 to 1.72, the gas-particle mixing uniformity is enhanced, which is beneficial to the uniform temperature distribution. Comprehensively, the L D of 1.43–1.72 is recommended when radial air staging is adopted in coal-fired industrial boilers. • The radial air staging method accelerates the mixing of OFA and the main airflow while reducing the mixing intensity. • With the increase of L D , the obstructing effect by radial OFA on the diffusion of the swirling main airflow is weakened. • The increased L D facilitates gas recirculation in the main combustion zone, which is conducive to stable combustion. • The mixing uniformity of GPF increases with L D in general, promoting the uniformity of temperature distribution. [ABSTRACT FROM AUTHOR]

Hybrid diesel multiple units (HDMU) are considered an effective way to reduce fuel consumption and pollution emissions in regional non-electrified railways. To minimize the fuel consumption of HDMU, this paper formulates an integrated optimization of driving strategy and energy management. By introducing convex relaxation and linearization, we propose a second-order cone programming method to solve this integrated optimization. Case studies of multiple scenarios validate the effectiveness and robustness of the proposed method. In addition, the simulation results show that compared with the sequential optimization with the step-by-step improvement of driving strategy and energy management, the integrated optimization considers the battery characteristics when optimizing the driving strategy and reduces the electric braking power of the train, thus allowing the battery to absorb more braking energy and reduce fuel consumption. • Integrated optimization of driving strategy and energy management for hybrid diesel multiple units. • An optimization method based on second-order cone programming is proposed. • Compared with sequential optimization, the fuel consumption of integrated optimization is reduced by an average of 6.3%. • Different methods for solving integrated optimization are compared and analyzed. • Optimal driving strategies and energy management with different travel times are compared. [ABSTRACT FROM AUTHOR]

Abstract The increase in prices and our dependence on fossil fuels coupled with concerns about harmful emissions have motivated researchers to look for renewable and alternative fuels that have clean combustion and which can be produced locally. The fumigation of ethanol in diesel engines has been recognized as an effective alternative to improve efficiency and to reduce emissions. In this paper, the effects of a compression ignition engine using B7 and hydrous ethanol by fumigation method has been investigated. Hydrous ethanol was injected in the engine intake manifold by a port fuel injector, representing ethanol energy ratios from 11.5% to 52.3%. The results indicated a maximum decrease about 69% in smoke index, reduction in exhaust gas temperatures and reduction in both CO and CO 2 emissions. The lowest CO emission found was 0,11% and CO 2 emissions were 4.6% by volume. A maximum increase of 26.2% in thermal efficiency and 22.9% in exergy efficiency was observed. Nevertheless, an increase in HC emissions and specific fuel consumption was noted, achieving the maximum values of 121 ppm and 270.2 g/kWh, respectively. The results were satisfactory, confirming the potential to use ethanol fumigation method to improve thermal and exergy efficiency and reduce harmful gases. Highlights • B7 is direct injected and hydrous ethanol is fumigated in a diesel engine. • Ethanol energy ratio ranged from 11.5% to 52.3%. • Decreased CO, CO 2 emissions, smoke index and exhaust gas temperature. • Increased thermal and exergy efficiencies as well as SFC and HC emissions. [ABSTRACT FROM AUTHOR]

Abstract To reduce toxic engine emissions and meet the strict regulations, split injection has been adopted to optimize engine performance and fast-idle has been selected as the researching condition. Two sets of experiments have been conducted to investigate the effect of split injection on particulate number (PN) emissions at fast-idle. The first set is conducted in a constant volume vessel to get detailed spray characteristics, while the second is conducted in engine bench analyzing the effect of split injection on real engine PN emissions. Establishing direct connection from spray characteristics and real engine PN emissions is the main objective of this paper. Higher ambient temperature can reduce spray angle, while spray tip penetration is insensitive to experimental parameters. Long injection pulse width combined with short height of damper (HOD) will increase the possibility to impingement. Total PN concentration of four injection modes all decreases at first and then increases with increasing coolant temperature, and split injection can obviously reduce total PN to 50% from single injection. With increasing coolant temperature, accumulation mode particles all decrease while nucleation mode particles show different trends under four injection modes. In addition, the last injection within split injection has obvious influence on PN emissions. Highlights • Long injection pulse combined with short HOD will cause fuel impingement. • Higher temperature makes total PN decreases at first and then increases. • Split injection can obviously reduce total PN to 50% from single injection. • Higher temperatures change particle size distribution from bimodal to unimodal. • The last injection within split injection has obvious influence on PN emissions. [ABSTRACT FROM AUTHOR]

Abstract This paper performs a multi-model comparison to assess strategies for adaptation to climate change impacts in hydropower generation in Brazil under two Representative Concentration Pathways. The approach used allows for evaluating the interactions between climate change mitigation and adaptation strategies under low and high impact scenarios through 2050. Climate change impact projections of sixteen General Circulation Models indicate that a global high emissions trajectory scenario would likely yield more severe impacts on hydropower generation than a mitigation scenario. Adaptation modeling suggests that climate change impacts can be compensated by a wide range of alternatives, whose optimality will depend on the level of mitigation effort pursued. Our results show that climate change impacts would lead to even higher emissions in the absence of climate change mitigation policies. On the other hand, mitigation strategies to pursue lower emissions are maintained under climate change impacts, meaning that mitigation strategies are robust when faced with adaptation challenges. Mitigation efforts could yield a more diverse and less carbon intensive mix of technological options for adaptation. When analyzing investment costs to adapt to climate change impacts, in some cases mitigation can lead to a lower total investment level. Highlights • Climate change impacts on hydropower are assessed for sixteen models and two scenarios. • Interactions between climate change mitigation and adaptation are analyzed. • Adaptation/mitigation strategies from six different energy models are compared. • Adaptation and mitigation investment costs are assessed and compared. [ABSTRACT FROM AUTHOR]

Abstract The paper explores the way the environmental technical efficiency and productivity in the electricity and gas sectors of 13 EU countries have changed under the energy market reorganisation fostered by the EU energy reforms between 1995 and 2013. Using a multiple output distance function approach, we find that regulation encouraging privatisation and removing barriers to entry into the market had positive consequences on both environmental technical efficiency and the growth of environmental productivity. We find that the sector has made significant steps in improving its competitiveness and environmental sustainability, showing an annual average potential of 5.9% value-added gains and 5.6% CO 2 emissions reductions. However, the improvements in environmental performance differ greatly across countries and, at times, come at the expense of economic benefit whereas environmental productivity change (3.2%) grew slower than the productivity change that did not account for emissions. Regarding improvements in environmental productivity, the main source came from environmental technical change (2.4–2.8%), underlying the role of research and development on energy transition. Highlights • The energy sector could realise 5–6% value-added gains and CO 2 emissions reduction. • Technical change was the main source of environmental productivity improvements. • Market reforms had a positive effect on environmental technical efficiency. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the dynamic long run relationship between CO 2 emissions, economic growth, financial development, trade openness, industrialization, urbanization, coal and noncarbohydrate energy consumption within the framework of environmental Kuznets curve (EKC) for Turkey over the period 1971–2014. The two main contributions of this study are that the EKC hypothesis has been examined by separating trade openness and final energy consumption into import-export and coal-noncarbohydrate energy consumption respectively. The findings of the autoregressive disturbed lag bounds testing approach showed that economic growth, coal consumption, financial development, import, industrialization and urbanization had a positive impact on CO 2 emissions, while export and noncarbohydrate energy consumption decreased CO 2 emission in the long run. Moreover, the study supported the EKC hypothesis, which suggests an inverted U-shaped relationship between per capita income and CO 2 emissions. The turning point obtained from long run regression was found to be approximately $14360 that outside of the sample period. Finally, these important findings indicate that noncarbohydrate energy consumption and export can be a solution to reduce environmental pollution, and Turkey's CO 2 emissions will begin to decline when the country reaches the per capita income level at the turning point in the coming years. [ABSTRACT FROM AUTHOR]

Hybrid renewable energy system (HRES) has been widely utilized on national, regional or building levels, as its ability of reducing carbon emissions and easing energy consumption intensity. Techno-economic analysis of HRES is essential to embody its superiority and identify what kind of system and corresponding considerations are needed for a certain situation. This paper presents a comprehensive review of techno-economic analysis methods for the systems at national, regional and building scales. All methods are discussed in a comparative way including 31 computer tools and 20 arithmetical models. Main features, applications and merits of these methods are introduced and compared in detail regarding the analyzed space. Problems such as improper use of analysis methods or ignoring specific considerations may occur in the process of HRES designing and evaluating. As a result, a framework is proposed for techno-economic analysis of HRES at different spatial scales, including promising analysis process, research constraints and recommended tools for fulfilling different objectives. This framework provides critical references for researchers, decision makers and system designers, further supporting the application of future HRES. [ABSTRACT FROM AUTHOR]

Nowadays, there is a growing interest in the microgrid systems with a high penetration of renewable sources. In this paper, the modified harmony search (MHS) algorithm is proposed to solve the combined economic emission dispatch (CEED) problem of the microgrid taking into account the solar and wind power cost functions. The proposed algorithm can be derived by not only adjusting the parameters but also improving the structure and operation of the original harmony search (HS) algorithm. The solution of the CEED problem of the microgrid taking into account the solar and wind power cost functions is obtained for different scenarios using the MHS algorithm and some recently published algorithms. The results of all scenarios show the effectiveness of the MHS algorithm over other published algorithms employing same data. [ABSTRACT FROM AUTHOR]

This paper assesses the potential effects on the U.S. economy if the U.S. retreats from its pledge to reduce greenhouse gas emissions agreed under the Paris Agreement. We assume prior to withdrawal that the U.S. and other nations or regions would introduce climate change policies, such as emissions trading schemes, to meet their emission targets which were agreed in Paris. When the U.S. withdraws from the Paris Agreement, it will not adopt such a policy. We use a modified version of the GTAP-E model to examine the effects on the U.S. economy of its anti-mitigation action in a counterfactual framework. The findings suggest that a retreat from the Paris Agreement would increase the real GDP and real private consumption by 1.13% and 0.78%, respectively, in the U.S. Given such improvements at the macro level, the effects on the U.S. energy sectors from the withdrawal are substantial. Prices of energy would reduce considerably, particularly for coal, natural gas, and consequently the price of electricity (−17.8%). These three energy sectors would also experience considerable expansions when the U.S. withdraws from the Paris Agreement compared to its position if it honored its previously pledged committed targets. [ABSTRACT FROM AUTHOR]

In this paper, the short-term scheduling of fuel cell and combined heat and power based microgrid by considering cost and emission minimization and different demand response program, as a multi-objective microgrid dispatch problem, is studied. In order to reduce operational cost, time of-use and real time pricing demand response programs have been modeled, and the effects of these programs on the load profile have been discussed. The Pareto solutions in multi objective model are generated by using the ε-constraint method which transforms the multi-objective optimization problem into a single-objective problem and the optimal solution has been chosen by implementing fuzzy satisfying approach. The microgrid contains a fuel cell unit, two combined heat and power generation units, power-only unit, boiler, battery storage system, and heat buffer tank. The application of the proposed method is investigated and three cases have been studied. The first case is solved without considering demand response programs. In other two cases time-of-use rate demand response and real time pricing demand response are considered respectively and the impact of demand response programs on microgrid scheduling is discussed. To model the proposed cost-emission operation scheduling of microgrid a mixed-integer linear program is used and solved by GAMS software. [ABSTRACT FROM AUTHOR]

Efficient solving of practical optimization problems in important fields like the energy and its peripheral problems has been an ever-growing attractive topic for many academicians and industries during the recent decades. This paper introduces a swarm-based optimization method, namely the Floating Search Space , to solve one of the most important energy problems called the “ Economic and Emission Dispatch ”. The proposed method, which resizes and floats the allowed search region inside the main search space, is attached to three versions of swarm intelligence-based Optimization algorithms, as a supplementary approach, to enhance their performance and achieve high quality solutions in a more reliable way. The proposed method, which receives online feedbacks from the population to regulate itself and define most promising areas inside the search space is a simple parameter-free technique which can be easily attached to any intelligent optimizer. Simulation results approve that the proposed method is able to obtain competing solutions to the real-world modeled Economic and Emission Dispatch problems by increasing the accuracy, decreasing computational budget, and achieving more robust performance by reducing stagnations and rising success rate. [ABSTRACT FROM AUTHOR]

This paper proposes an Enhanced Moth-Flame Optimization (EMFO) algorithm for solving the non-convex economic dispatch (ED) problem with valve point effects and emissions. It determines the optimal generation schedule of generating units by minimizing both fuel cost and emission simultaneously while the system constraints are achieved. The moth-flame optimization (MFO) is a recent nature-inspired method, which is based on the navigation mechanism called transverse orientation of Moths in space. The EMFO combines the merits of the traditional MFO and levy flight by concentration the search space. The usage of L é vy-flight has the prominent properties to increase the diversity of population. The effectiveness of the proposed EMFO method is proven on using 10 benchmark functions and 3 standard test systems consisting of 6, 40 and a large scale 80 generating units with non-convex fuel cost functions. The capability of the proposed algorithm is verified also for single and multi-objective studied cases and its results are compared with several well-known previous techniques. The results confirm the high performance of the proposed EMFO method for finding the optimal economic generation scheduling at acceptable low emission levels. [ABSTRACT FROM AUTHOR]

Cement industry is highly energy and emissions intensive. Thermal energy is majorly used in the kiln and calciner systems, accounting for over 90% of total energy use in cement plant, and virtually all of the fuel use. Therefore, the precalciner is one of the key equipment in cement manufacturing process impacting the energy efficiency of the pyroprocessing unit. The purpose of this paper is to demonstrate the potential of statistical modeling to support the optimization of precalciners. According to the current knowledge of the authors, this is the first investigation using statistical models to optimize combustion system operating conditions by analyzing historical and experimental design data. Multiple linear regressions were obtained for each of the two approaches with statistically comparable variances. It should be noted that the optimum obtained with the experimental design is better because the corresponding model describes a larger range of operating variables. On the basis of the experiment-based model, 60% of the total unburned organic carbon could be reduced. [ABSTRACT FROM AUTHOR]

A super credit policy provides favorable accounting rules for extremely low emission vehicles under several passenger vehicle fuel economy regulations. This policy was initially designed to promote promising advanced technologies complying with fleet-wide fuel economy regulations so that these technologies could achieve cost-effective breakeven points. The favorable multipliers offered range from 3.5 to 1.33 in the various fuel economy regulations by the year 2021. Under China's Corporate Average Fuel Consumption regulation, two types of super credit schemes are designed in the Phase IV Corporate Average Fuel Consumption regulation through 2020. One is the fuel-efficient vehicle super credit for vehicles with fuel consumption rates below the threshold of 2.8 L/100 km. Another is the new energy vehicle super credit for battery electric vehicles and plug-in hybrid electric vehicles. However, the effectiveness of this incentive in promoting electric vehicles and the optimal size of the multiplier are not well understood. This paper analyzes the impacts of the super credit policy from the perspective of automakers. A mathematical model based on combinational optimization is established to describe an automaker's decision-making process, and a genetic algorithm is employed to solve this problem. The conventional and plug-in hybrid electric vehicles cost-effectiveness frontier curves are fitted to illustrate the principle of new energy vehicle and fuel-efficient vehicle super credit schemes. Various multipliers of new energy vehicle and fuel-efficient vehicle super credit policy scenarios are simulated under the 2020 and 2025 Corporate Average Fuel Consumption targets. By analyzing the impact of the policy on the reduction of compliance costs, the super credit multiplier, the cost and the fuel consumption rates reduction effect are found to be the determining factors. The results confirm that the multiplier and China's super credit policy scheme will be effective by 2020, under which plug-in hybrid electric vehicles would account for 7.8% of the fleet at a cost of 6.6% Corporate Average Fuel Consumption target impairment. Under the assumed next phase of regulation by the year 2025, the optimal multipliers for the new energy vehicle and fuel-efficient vehicle super credit will be 1.5 and 1, respectively. It is noteworthy that the super credit policy may impair the energy saving target of Corporate Average Fuel Consumption regulations while promoting the market penetration of the targeted technologies. Despite other policies that benefit battery electric vehicles over plug-in hybrid electric vehicles, battery electric vehicles are not competitive with plug-in hybrid electric vehicles under either the 2020 or 2025 Corporate Average Fuel Consumption regulations. The fuel-efficient vehicle super credit policy will not promote the targeted advanced technologies under the next phase of regulation unless the 2.8 L/100 km fuel-efficient vehicle definition threshold can be adjusted along with the strengthened 2025 Corporate Average Fuel Consumption target. [ABSTRACT FROM AUTHOR]

Voluntary carbon trading has long been criticized for producing a large number of non-additional offsets. The reason for this production lies primarily in the use of a project-based baseline that misrepresents the business-as-usual (BAU) emissions of individual projects. Performance baseline however, as an alternative baseline approach, does not rely on evaluating individual BAU emissions. Instead, it uses a pre-defined emission threshold for a class of project activities. This paper compares the effects of the two baseline approaches on sectoral emission mitigation and compliance costs by modeling dynamic emission abatement behaviors. In the context of the U.S. commercial building sector, the modeling results indicate that while both baseline approaches are capable of reducing sectoral emissions, the use of performance baseline is especially advantageous under private cost information and uncertain market environments. The performance baseline should be stratified by region to ensure the equity in offset allocation in sectors that are highly diversified in emission magnitudes. [ABSTRACT FROM AUTHOR]

The issue of environmental emissions has forced the power systems to use cleaner energy sources such as renewable and hydroelectric technologies. However, during recent decades due to the limitations on the available water in many regions, the optimal water reservoir usage has been highlighted. In this regard, this paper proposes a multi-objective model for short-term hydrothermal scheduling problem in the presence of the pumped-storage technology. It is noted that the framework well models the cascaded configuration of hydro reservoirs. Besides, in order to more accurately model the mentioned problem, a Mixed-Integer Non-Linear Programming (MINLP) optimization framework is presented. In this respect, the valve-loading effects occurred in thermal power generation technologies have been taken into account which turns the existing convex optimization problem into a non-convex one. In order to solve the mentioned problem, the Normal Boundary Intersection (NBI) method has been used while the VIKOR decision maker is employed to choose the most compromise solution amongst the Pareto optimal solutions obtained by NBI method. Finally, the efficiency of the proposed model has been verified through implementing four case studies and comparing the obtained results with those obtained by different methods. [ABSTRACT FROM AUTHOR]