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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: The Scandinavian mechanical pulp and paper industry has been facing great challenges during the past decades, mainly because of declining demand for newsprint, and higher prices on raw material and energy. One way of increasing profitability is to produce more value-added products besides the production of pulp and paper. In this study, integration potentials of three possible future biomass gasification-based energy mills with an existing thermo-mechanical pulp (TMP) mill, co-located with a sawmill, have been evaluated. The product gas was utilized for electricity production in a gas turbine, for production of methanol or for production of Fischer–Tropsch (FT) liquids. Integration of the energy mills showed good potential as the TMP mill constitutes a heat sink for which the excess heat from the energy mills can be utilized all year round. However, since there is little excess heat from the TMP mill at the required level to be utilized for biomass drying, for example, heat integration is typically one way. It has also been shown that integration of biomass gasification with a TMP mill results in larger CO2 emissions reduction than stand-alone operation. Still, compared to co-firing biomass in a coal power plant, the energy mills all have lower potentials for CO2 emissions reduction. [Copyright &y& Elsevier]

The current study analyzes the potential of an environmentally benign integration of a parabolic trough solar collector (PTSC) with a heat-intensive multi-effect evaporator (MEE) used in pulp and paper industry. Actual plant data was used to simulate the MEE and estimate the steam economy (SE) and steam consumption (SC), which are used to judge the performance of PTSC-MEE system. Four distinct alternatives for the integration are investigated with Self-adaptive Differential Evolution (SaDE) utilized for optimization. Initially, a normal PTSC with four different model configurations of MEE, basic or with energy reduction schemes (ERSs) are tested and found that SE is slightly increased for each. Next, a geometrically optimized/combinatorial optimized PTSC with basic MEE is examined, a rise of ∼3.4% in SE is noted for both, with current integration outperforming one out of three ERSs. Subsequently, geometrical plus combinatorial optimized PTSC with basic MEE is inspected, increase in SE reached 7.59% and two of the three ERSs outperformed. Economic analysis is conducted to estimate the steam saving with different PTSC-MEE systems and corresponding payback periods. The possibility of decarbonization with the various integration possibilities is also explored by evaluating the fuel savings and related CO 2 savings. • Integration of PTSC with an MEE used in pulp and paper industry is investigated. • The fusion of PTSC with MEE is studied with various possibilities. • Self-adaptive Differential Evolution (SaDE) is used for various optimizations. • The steam savings and payback times are estimated for various PTSC-MEE systems. • Decarbonization is studied by analyzing fuel savings and CO 2 reductions. [ABSTRACT FROM AUTHOR]

Abstract: India accounts for 4.5% of industrial energy use worldwide. This share is projected to increase as the economy expands rapidly. The level of industrial energy efficiency in India varies widely. Certain sectors, such as cement, are relatively efficient, while others, such as pulp and paper, are relatively inefficient. Future energy efficiency efforts should focus on direct reduced iron, pulp and paper and small-scale cement kilns because the potentials for improvement are important in both percentage and absolute terms. Under business as usual, industrial energy use is projected to rise faster than total final energy use. A strong focus on energy efficiency can reduce this growth, but CO2 emissions will still rise substantially. If more substantial CO2 emissions reductions are to be achieved then energy efficiency will need to be combined with measures that reduce the carbon intensity of the industrial fuel mix. [Copyright &y& Elsevier]

Faced with the difficult but urgent task of reducing carbon emission intensity, considering urban agglomeration as a fundamental spatial unit for this purpose has become increasingly important. However, as a long-standing and pivotal phenomenon in the development of urban agglomerations, the potential role of spatial functional division in urban agglomerations in reducing carbon emission intensity has been largely overlooked. To fill this gap, this paper explores the relationship between spatial functional division in urban agglomerations and carbon emission intensity, relying on a dataset of 19 urban agglomerations in China. The main results reveal an inverted U-shaped relationship between spatial functional division in urban agglomerations and carbon emission intensity. Spatial functional division in urban agglomerations increases carbon emission intensity in the initial stage; once it reaches a turning point, spatial functional division in urban agglomerations can reduce carbon emission intensity. This conclusion remains robust after conducting various robustness checks and addressing endogeneity concerns. This paper identifies productivity enhancement as an underlying mechanism that shapes this relationship. Moreover, the relationship between spatial functional division in urban agglomerations and carbon emission intensity exhibits heterogeneity based on function types and urban types. These findings emphasize that spatial functional division in urban agglomerations plays a unique role in reducing carbon emission intensity, which offers a new strategy for reducing carbon emission intensity from an individual city level to an entire urban agglomeration level. • An inverted U-shaped relationship exists between SFD and CEI. • Productivity enhancement derived from SFD is a crucial influencing mechanism. • Function types and urban types influence the relationship between SFD and CEI. • Improving SFD adds a novel urban agglomeration-level strategy to reduce CEI. [ABSTRACT FROM AUTHOR]

The carbon neutrality agenda requires that carbon lock-in enters an endgame. A well-developed energy system, which is secure, equitable, and sustainable is paramount to getting rid of carbon lock-in and realizing decarbonization. We carry out systematic research to empirically study the possible carbon lock-in reduction effect of energy trilemma based on the instrumental variable-generalized method of moment (IV-GMM) model. We also detect heterogeneous effects in terms of geographical locations and endowments of capital, as well as the impact mechanisms. Moreover, this paper highlights the mediating and threshold role of environmental regulation. We thus get the following conclusions. (1) The paper's primary findings underscore that the continuous increase of energy trilemma exacerbates carbon lock-in and hampers the process of decarbonization; (2) Energy trilemma has a higher stimulating effect on carbon lock-in in provinces that lie in the central region and that have a comparatively low level of physical, social, and human capital; (3) Energy trilemma can also indirectly aggravate carbon lock-in by inhibiting technology innovation and exacerbating carbon emissions intensity; (4) The interaction of environmental regulation and energy trilemma can alleviate the energy trilemma - carbon lock-in nexus, and environmental regulation also shows a significant threshold effect. • We investigate the impact of the energy trilemma on carbon lock-in. • Energy trilemma eradication is an effective way to realize the carbon lock-in endgame. • The nexus between energy trilemma and carbon lock-in is more prominent in provinces with high capital endowments. • Environmental regulation shows significant mediating and threshold effects. • The exacerbate carbon lock-in effect of energy trilemma depends on technology and intensity effect. [ABSTRACT FROM AUTHOR]

Industrial chain structure optimization and digital transformation are crucial factors for achieving carbon emission reduction goals. Based on China's non-competitive input-output tables, this paper constructed industrial chain panel data using the structural path analysis method. We explored the influence of industrial chain division (ICD) on CO 2 emission intensity through panel fixed effects model, and examined the moderating effect of digitization. The research found that: (1) The ICD can significantly reduce CO 2 emission intensity, the results are robust after some endogeneity tests. (2) The emission reduction effect brought by ICD will be more obvious in high-stage, high-energy consumption, and high-intelligence industrial chains. There is still room to improve the emission reduction brought by the division network effect. (3) Digitization plays a positive moderating role on this effect. Furthermore, digital manufacturing and digital services exhibit heterogeneity in various types of industrial chains. (4) The ICD can reduce carbon emission intensity through pathways such as intelligent transformation, technological innovation, and energy efficiency, and digitization has positively moderated these impact pathways. Based on research results, targeted policy suggestions are provided for optimizing industrial chain structure and promoting digital transformation. • This paper constructed industrial chain carbon emission intensity panel data. • This paper assessed the industrial chain digitization by digital intermediate input. • This paper constructed industrial chain synergistic division (ICSD) index. • This paper explored the influence of ICSD on CO 2 emission intensity. • Digitization plays a positive moderating role on carbon emission reduction effect. [ABSTRACT FROM AUTHOR]

Whether renewable energy consumption is beneficial to reducing CO 2 emission intensity and carbon emissions in the context of the goal of "carbon peak and carbon neutrality" in China. To prove this conjecture, considering the spatial spillover effect of carbon dioxide, this paper adopts the spatial Dubin model for empirical analysis based on the panel data of China's 30 provinces over the period 2002–2019. This study explores the CO 2 intensity mitigation effect of China's renewable energy consumption and further investigates the mediation role of technological innovation, industrial structure upgrading and optimization, and energy efficiency in the nexus between renewable energy consumption and carbon intensity. The main findings present that: (1) China's carbon emission intensity is characterized by significant spatial correlation; (2) Renewable energy consumption can significantly reduce carbon intensity and per capita carbon emissions; (3) The mediation effect of renewable energy consumption in reducing carbon emission intensity is to promote technological innovation and industrial structure upgrading, as well as improve energy efficiency. Based on the conclusions, this paper offers several policy implications for governments to reduce CO 2 emission intensity. • The impact of renewable energy consumption on CO 2 emission intensity is explored. • Renewable energy consumption can reduce carbon emission intensity and per capita carbon emissions. • Renewable energy consumption reduces CO 2 intensity through the spatial mediation effect. [ABSTRACT FROM AUTHOR]

This paper compares the macroeconomic impacts of different decarbonization storylines until 2050 using two Computable General Equilibrium models. The modeling shocks are harmonized across models to simulate four decarbonization scenarios through three main drivers: technical development, societal attitude, and policies. The study explores the contribution of each of these drivers to the European decarbonization. The results show that the decarbonization scenarios have moderate effects on GDP; decarbonization scenarios rather result in sectoral shifts. The impact of temperature on labor productivity minimally alters expected growth levels, since larger differences in temperature between the scenarios are only expected to occur in 2100, not yet in 2050. Electricity demand is increasing in all scenarios, particularly with stronger political guidance leading to additional tax and subsidy measures to encourage the use of electricity and discourage fossil-based fuels. When society is a driving factor, it is found that circular business models result in an increase in the service industry but might have a slightly negative impact on overall growth due to stronger spillover effects linked to the manufacturing industry. Technology appears to be the only driver to facilitate decarbonization while maintaining steady economic growth. • We address the macroeconomic effects of five climate scenarios using two CGE models. • We focus on the effects of changes in society, technology, and policy. • We incorporate climate change effects through labor productivity. • Effect of decarbonization on GDP is moderate under given technological improvement. • Decarbonization scenarios result in relatively large sectoral shifts. [ABSTRACT FROM AUTHOR]

Abstract Recently, there is an upsurge interest of using biomass derived char products in various fields, in order to address some of the most urgent energy and environmental problems we are facing today, such as CO 2 emission, energy crisis and environmental pollution. In this review paper, most recent studies on biochar/hydrochar production, characterization and prospective utilizations are summarized. Fundamentals and reaction mechanisms of biochar/hydrochar formations are discussed in detail. The energy balance and economic flexibility of biochar production technology is also analysed. The effects of reaction temperature, feedstock types, and thermochemical conversion modes on biochar are compared. In addition, we highlighted benefits and potential challenges in promoting biochar application in energy and environmental fields, including the applications in adsorbents, precursor of catalysts, soil amendment, anaerobic digestion and composting, and electrochemical energy storage materials. This paper not only summarises recent advances in engineered biochar technology but also demonstrates insights on new directions for biochar research and development in the future. Highlights • Biochar has enormous potential for ever-increasing energy and environmental demands. • Formation, properties and applications of biochar/hydrochar are summarized. • Biochar properties are influenced by temperature, feedstock and conversion modes. • The mechanisms of biochar/hydrochar generation are comprehensively summarized. • Biochar applications in energy, waste management and agriculture are reviewed. [ABSTRACT FROM AUTHOR]

Abstract Asia has become a major emitter of carbon emissions. To better achieve emission reduction targets, it is necessary to study the characteristics of carbon dioxide emissions in Asia and their emission reduction potential. Firstly, the gravity movement of Asia's carbon dioxide emissions and its leading forces are explored. Then, the Logarithmic Mean Divisia Index method is applied to find the driving factors governing carbon dioxide emissions. Furthermore, this paper establishes a theoretical model of carbon dioxide emission reduction. At last, the influencing factors are utilized to construct a decoupling index, which is used to describe the dependence of economic development on carbon dioxide emissions. The gravity center for Asia's carbon dioxide emissions was an overall movement towards southwest. However, the gravity center for carbon dioxide emissions per capita was an overall movement towards the southeast. The energy intensity effect was the most factor decreasing Asia's carbon dioxide emissions. Only five countries achieved theoretical reduction of carbon dioxide emissions over 2000–2015. However, three countries were failed to achieve the theoretical reduction of carbon dioxide emissions in this period. The economic development in most east Asia and southeast Asia countries was less dependent on energy-related carbon dioxide emissions over the period 2000–2015. Highlights • The gravity movement of Asia's CO2 emissions and its leading forces were explored. • This paper established a theoretical model of carbon dioxide emission reduction. • This paper constructed a decoupling index. [ABSTRACT FROM AUTHOR]

Abstract This paper explores the effects of enforced Chinese policies regarding environmental matters at the provincial level. The paper proposes several features and explores datasets from the last four Five-Year Plans, which extensively covered the period from 1995 to 2015. As the datasets are multidimensional, dimensional reduction is applied with a control of information loss described by data variance preservation. A data-based clustering algorithm is applied to identify the similarities, and characteristics are explored in relation to the specific features. The use of this method makes it possible to identify the changes in the relevance of the features in the most recent Five-Year Plan, in which decarbonization is relevant instead of productivity. This method also makes it possible to identify specific efforts several provinces have made to introduce cleaner energy production. Following the analysis, it is concluded that the proposed features enable the proposed method to be considered a tool for analyzing the real-world effects of the adopted policies. [ABSTRACT FROM AUTHOR]

Abstract Global climate change is a significant environmental problem. A major trigger of climate change is the excess carbon emissions. Based on 44 scenarios in the second generation of new dry cement technology systems, this paper establishes IPSO-BP model to forecast the carbon emissions peak of China's cement industry for 2016–2050 years. The results indicate that China's cement industry only implements capacity reduction plans and the second generation of new dry cement technology systems, so that carbon emissions can reach the peak before 2030. It is up to 19 years ahead of the carbon emissions peak of the basic scenario and the carbon emissions peak is reduced by 38 Mt. Moreover, this paper analyzes the technical combination of the earliest carbon emissions and the lowest carbon emissions. As for the earliest carbon emissions technical combination, China's cement industry carbon emissions will peak at 789.95 Mt in 2021. According to the lowest carbon emissions technical combination, China's cement industry carbon emissions will peak at 742.37 Mt in 2025. Accordingly, the conclusions will be helpful for making carbon emissions reduction policies for China's cement industry. Highlights • Carbon emission levels were reviewed from industrial output and technologies. • The prediction model of carbon emissions was built with improved PSO and BPNN model. • The scenarios were set to analyze carbon emission peak in China's cement industry. • Importance of technique and capacity reduction in China's cement industry is defined. • The best carbon emission peak plan for China's cement industry is discussed. [ABSTRACT FROM AUTHOR]

Ammonia is receiving increasing attention as a zero-carbon fuel. However, it is difficult to use alone because of its high auto-ignition temperature. Therefore, in this paper, the effects of four ammonia energy ratios (15 %, 30 %, 45 %, and 60 %) on the combustion and emission characteristics of the engine at different loads were studied by using the ammonia/diesel dual-fuel strategy. The results indicated that the presence of ammonia lowered the combustion temperature at all loads, thereby lowering the cylinder temperature and cylinder pressure. In addition, the HRR first increased and then decreased as the ignition delay increased with the increase in ammonia energy ratio. In terms of emissions, at 100 % load, the CO 2 and NO of the D40A60 were 65.5 % and 88.14 % lower than that of the D100. The decrease in CO 2 was due to more carbon-based fuels being replaced by ammonia. The decrease in NO was due to the decomposition of NO by the thermal deNO x reaction resulting from the lower combustion temperature. The emissions of N 2 O produced by partial ammonia oxidation offset the greenhouse gas emission reduction effect caused by the reduction of carbon dioxide emissions. Further optimization of the engine combustion strategy is still needed in the future. • The combustion characteristics of engines with different AERs at different loads are investigated. • The effect of different AERs on various emissions is presented. • An increase in AER is observed to increase N 2 O and GHG emissions. • Increasing the engine load can improve the emissions of unburned ammonia. [ABSTRACT FROM AUTHOR]

—Regarding the increase of carbon dioxide emissions with growing energy demand, recent emerging technologies for multi-energy system have attracted much attention, as they can effectively couple and coordinate different energies to further control carbon dioxide emissions. This paper focuses on distribution-level multi-energy system and proposes an optimal scheduling method for hydrogen support based on dual-agent energy-carbon price interactive response. Firstly, a hydrogen-supported multi-energy closed-loop flow mode is developed, which provides an effective way to improve renewable energy consumption and brings additional economic revenue of solid carbon. Secondly, a dual-agent energy-carbon price interactive response scheme is designed based on the concept of energy-carbon participation ratio, which takes carbon dioxide emissions of gas load and various carbon revenues into account. This scheme can motivate users for energy demand adjustment and active carbon dioxide reduction by setting energy and carbon prices as two guiding signals. Finally, a bi-level optimal scheduling model is proposed for dual agents of energy service provider and users to maximize the benefit of each side. Case study illustrates that the proposed model can effectively balance benefits of dual agents and has economic advantage of carbon dioxide reduction, while promoting the consumption of high proportion renewable energy and system stability. • Hydrogen-supported multi-energy closed-loop flow mode is developed. • DECIR scheme is designed for active energy adjustment and CO 2 reduction of users. • Bi-level scheduling model balancing both benefits of dual agents is proposed. • The proposed model improves the economy, low carbon and stability of MES. [ABSTRACT FROM AUTHOR]

Access to clean energy has a positive impact on societies, whereas excessive extraction of fossil fuels along with population growth, traps the world into serious problems. Global energy strategy is a manner to find a balance between positive and negative impacts of energy on societies, especially their quality of life. This paper proposes a framework to choose a decent global energy strategy in the presence of five factors including final energy consumption, quality of life, poverty, health, and carbon dioxide emissions. The core of the framework is “Trade-off Analysis”, which its outputs are analyzed by three defined scenarios in the presence of total population. According to the results, mitigation of carbon dioxide emissions and preservation of the natural energy sources are two factors with a higher priority to encourage developed countries to reduce energy consumption. In case of developing countries, in addition to the two previous factors, the poverty and quality of life are next priorities. For pre-developing countries, the first priority is poverty reduction, then health and quality of life improvement. Thereby, the paper proposes the eco-sufficiency and eco-efficiency policies for developed and developing countries respectively, while energy poverty policy for pre-developing countries. [ABSTRACT FROM AUTHOR]

Determining the carbon impact of commercial developments is an essential starting point in understanding a company's carbon footprint. It is also integral to the development of a strategy to reduce that impact in a cost effective manner. There are numerous industry standard carbon calculation methodologies. This paper focuses on the application of one such method, the Greenhouse Gas (GHG) Protocol, and applied it to the unusual example of a UK safari park. The safari park management wanted to understand the park's impact on the environment as part of a long-term plan to reduce that impact by identifying realistic carbon reduction solutions. Actual monitored energy data for a twelve-month period were available as part of the analysis. The results of this paper show that the application of the GHG Protocol, in reality, and especially for a non-standard situation, is difficult. Effective performance monitoring is essential to enable transparent recording of data, from which a carbon footprint can be calculated. The methodologies for calculation are relatively straightforward but depend upon available information. Identification of the carbon impact of the development is the relatively easier task - the real challenge is reducing this impact to near zero in a cost effective manner. [ABSTRACT FROM AUTHOR]

Aircraft performance degradation causes higher fuel consumption. This results in higher emission and it is an important factor when the complete life cycle is analyzed. Current research in the field doesn’t quantify degradation emissions in the life cycle of an aircraft. The objective of this paper is to suggest a methodology for determining carbon dioxide emission during the life cycle of turbofan aircraft. Special attention is given to degradation and the importance of proper and timely maintenance as a way of controlling these emissions. Degradation plays a significant role in the carbon dioxide emission of turbo fan aircraft. The life cycle was modeled by eight sequences. In this paper a new mathematical interpretation is suggested for following life sequences: use and repair. In the use cycle, emission caused by aerodynamic structure degradation and engine degradation is calculated separately. The proposed methodology was implemented on four and tested on eight turbofan aircraft. Results show that more than 99% of carbon dioxide emission occurs in the use sequence. The emission caused by degradation (aerodynamic structure and engine) makes up between 3.6% and 6.4% of total carbon dioxide emission. A novel methodology for reducing emission caused by degradation is proposed by the authors. [ABSTRACT FROM AUTHOR]

This paper investigates environmental technical efficiency for a panel of European Union (EU) member and candidate countries for the period 1990–2011 using parametric hyperbolic distance function. The paper also examines the environmental technical efficiency convergence among the sampled countries. The main results suggest that environmental technical efficiency scores vary among EU member and candidate countries. The EU-15 countries in contrast to the new members and the candidate countries have a greater potential for reducing CO 2 emissions while increasing GDP and reducing energy use simultaneously. The results also indicate the existence of environmental technical efficiency convergence among EU member and candidate countries. [ABSTRACT FROM AUTHOR]

This paper employs an LMDI decomposition exercise to investigate the main factors that affect changes in CO 2 emissions of South Africa at national level within the BRICS group of countries (Brazil, Russia, India, China, and South Africa) from 1990 to 2014. From the results, it is expected to derive some information on the existence of the energy rebound hypothesis for South Africa with ultimate purpose to direct future research into examining the effect in a micro level. The aim of this paper is not to estimate the precise rebound effect but to decompose the determinants of emission changes in the BRICS countries. The concept of energy rebound would play a role if the improvements in energy intensity might lead to emission increases, instead of the opposite as expected. The overall results suggest that the changes in CO 2 intensity and energy intensity had a negative impact to the changes in CO 2 emissions: in other words, as the energy intensity (energy consumption per unit of economic output) decreased for all the countries (possible technological developments), the emissions kept rising. For South Africa specifically, the energy intensity was a negative contributor to CO 2 emissions only for the part of the examined period (2008–2014). [ABSTRACT FROM AUTHOR]

In this paper, economic and environmental impacts of energy efficiency programs associated with new and existing buildings are evaluated for the Kingdom of Saudi Arabia (KSA). In particular, the analysis considers optimized designs for new buildings as well as different energy retrofit programs for existing buildings are considered in the bottom-up analysis using archetypical building energy models located in five sites representing a wide range of KSA climates. In particular, the analysis presented in this paper provides specific estimations to the extent of the energy and demand savings that could be achieved in the building sector even under highly subsidized energy prices. It is found that even a basic energy retrofit program using low-cost energy efficiency measures implemented to the existing building stock can provide significant economic and environmental benefits. Indeed, a level 1 energy efficiency retrofit program targeting only the existing residential building stock could reduce electricity consumption by 10,054 GWh/year and peak demand by 2290 MW and carbon emission by 7.611 million tons/year. [ABSTRACT FROM AUTHOR]

Abstract: Black liquor gasification (BLG) is currently being developed as an alternative technology for energy and chemical recovery at chemical pulp mills. This study examines how different assumptions regarding systems surrounding the pulp mill affect the CO2 emission balances for different BLG concepts. The syngas from the gasification process can be used for different applications; this study considers production of renewable motor fuels and electricity generation. Both a market pulp mill and an integrated pulp and paper mill are considered as host mill for the BLG plant. Furthermore, the consequences of limited availability of biomass are shown, i.e., increasing the use of biomass in a mill is not necessarily CO2-neutral. The results show that the potential to reduce CO2 emissions by introducing BLG is generally much higher for a market pulp mill than for an integrated pulp and paper mill. Electricity generation from the syngas is favoured when assuming high grid electricity CO2 emissions where as motor fuel production is favoured when assuming low grid electricity CO2 emissions. When considering the consequences of limited availability of biomass, the CO2 emission balances are strongly affected, in some cases changing the results from a decrease to an increase of the CO2 emissions. [Copyright &y& Elsevier]

This paper investigates the existence of environmental Kuznets curve in Croatia for the period of 1992Q1-2011Q1. To fulfil to goals of the paper, Autoregressive Distributed Lag (ARDL) and VECM method has been applied. Results show the existence of inverted U-shape relation between CO 2 emissions and economic growth in long run that is the validity of EKC. Granger causality based on VECM approach shows bi-directional causality between CO 2 emissions and economic growth in short run and uni-directional causality from economic growth to CO 2 emissions in long run. DOLS and FMOLS results confirm the robustness of long run results. Variance decomposition and Impulse response also show similar results. Beauty of the paper is the consistency of results from different techniques. [ABSTRACT FROM AUTHOR]

Most of the existing district heating systems are second and third generation and operate with supply temperature above 80–100 °C. To meet long-term decarbonization targets, existing networks should be transformed into low-temperature systems in a cost-effective manner. This paper presents a critical review on the strategies that can be adopted to reduce the supply temperature in existing district heating networks taking advantage of previous studies (both research projects and scientific papers) and forerunner experiences. This includes a review of the constraints met during transition and the possible strategies/actions to overcome them, along with the actions to boost the change. The analysis shows that there is often significant room for improvement by exploiting the oversizing of network, substations and terminal units along with techniques, previously adopted with other aims, for a proper infrastructure/operation modification. Temperature reductions can be achieved without groundbreaking infrastructural modifications. Therefore, acting on specific subnetworks (the way usually adopted) is not the only way to proceed; this can be done in entire networks by adopting proper changes of perspective, policies and preliminary analysis. In the meantime, there is still need for specific approaches to estimate the main limitations and the corresponding best actions to implement in a specific network. [Display omitted] • Strategies to transform existing DH into low temperature systems are reviewed. • Experiences, project results, analyses and discussions are included. • Limitations due to network, substation and building are taken into account. • Possible solutions to overcome the various constraints are reviewed. • A possible action plan to implement the transition is proposed. [ABSTRACT FROM AUTHOR]

The current approach to hydraulic fracturing requires large amounts of industrial hardware to be transported, installed and operated in temporary locations. A significant proportion of this equipment is comprised of the fleet of pumps required to provide the high pressures and flows necessary for well stimulation. Studies have shown that over 90% of the emissions of CO 2 and other pollutants that occur during a hydraulic fracturing operation are associated with these pumps. Pollution and transport concerns are of paramount importance for the emerging hydraulic fracturing industry in Europe, and so it is timely to consider these factors when assessing the design of high pressure pumps for the European resources. This paper gives an overview of the industrial plant required to carry out a hydraulic fracturing operation. This is followed by an analysis of the pump's design space that could result in improved pump efficiency. We find that reducing the plunger diameter and running the pump at higher speeds can increase the overall pump efficiency by up to 4.6%. Such changes to the pump's parameters would results in several environmental benefits beyond the obvious economic gains of lower fuel consumption. The paper concludes with a case study that quantifies these benefits. [ABSTRACT FROM AUTHOR]

Turbocompounding is an important technique to recover waste heat from engine exhaust and reduce CO 2 emission. This paper presents a parametric study of turbocompound diesel engine based on analytical model. An analytical model was developed to investigate the influence of system parameters on the engine fuel consumption. The model is based on thermodynamics knowledge and empirical models, which can consider the impacts of each parameter independently. The effects of turbine efficiency, back pressure, exhaust temperature, pressure ratio and engine speed on the recovery energy, pumping loss and engine fuel reductions were studied. Results show that turbine efficiency, exhaust temperature and back pressure has great influence on the fuel reduction and optimal power turbine (PT) expansion ratio. However, engine operation speed has little impact on the fuel savings obtained by turbocompounding. The interaction mechanism between the PT recovery power and engine pumping loss is presented in the paper. Due to the nonlinear characteristic of turbine power, there is an optimum value of PT expansion ratio to achieve largest power gain. At the end, the fuel saving potential of high performance turbocompound engine and the requirements for it are proposed in the paper. [ABSTRACT FROM AUTHOR]

This paper construct a CCHP and renewable energy based hybrid energy system driven by distributed energy resources (DERs CCHP). Then, the paper constructs performance indexes from energy, economic and environment. Thirdly, the paper proposes a multi-objective optimization model for DERs CCHP system under four optimization of energy rate (ER), total operation cost (TOC), carbon dioxide emission reductions (CER) and joint optimization. Finally, Guangzhou Higher Education Mega Center (GHEMC) in China is taken as the object for comparatively analyzing the operation performance of DERs CCHP system and CCHP system driven by natural gas (NG CCHP system). Results show: Joint optimization mode could balance the results of different optimization modes. DERs CCHP system shows better operation performance. ER of ER optimization, CER optimization and joint optimization are higher than that of NG CCHP system. NPV of all optimization modes is positive, IRR are bigger than the expected yield rate. DERs CCHP system could reduce CO 2 emission by utilizing wind energy and solar energy to replace NG. The sensitivity analysis indicates the performance of the DERs CCHP system will become better with the increase of chiller COP, decrease of NG price and wind-photovoltaic equipment cost. [ABSTRACT FROM AUTHOR]

This paper focuses on the requirement of the Energy Efficiency Directive for assessing the potential of efficient heating and cooling. The paper describes the method for calculating the economic potential of efficient district heating (DH) in Austria under different scenarios, assuming the full decarbonisation of the heating sector by 2050. A spatially explicit approach is used to derive heat demand density maps, heat distribution costs and potential DH areas. The obtained areas are clustered, and depending on their potential spreads, up to four supply portfolios on the installed generation capacities are assessed in each cluster. While this method maintains the level of detail, it significantly reduces the number of required sensitivity analyses. Finally, the least cost portfolios of DH supply in each cluster are identified and compared with the costs of individual heat supply. The economic potential of DH by 2050 is calculated accordingly. The analyses revealed that the DH market share within DH areas is the main driver of DH competitiveness. Depending on the scenario, the economic DH potential varies between 13% and 50% of space and water heating demand in Austria. The extensive application of renewable gases in this sector was not economically feasible under any scenario. • A method for assessing national economic district heating potentials is presented. • Decarbonisation targets strongly affect the parameterization of the approach. • Connection rates have a significant impact on the total district heating potential. • In Austria the economic district heating potential can exceed 50% of heat demand. • Decarbonisation of the sector through renewable gases is not economically feasible. [ABSTRACT FROM AUTHOR]

Renewable lipids can be converted into jet fuel-range alkanes via catalytic hydrotreatment, and many researches have been conducted over the past few decades. Relevant specification for Hydroprocessed Esters and Fatty Acids Synthetic Paraffinic Kerosene (HEFA-SPK) has been approved by American Society of Testing Materials (ASTM), and lipids-derived aviation fuel has been used in the commercial flights because of its obvious advantages in the reduction of carbon dioxide emissions. This paper introduces production processes for sustainable aviation fuels by hydroprocessing of lipids. First, the properties of lipids and their pretreatment methods are introduced. Hydrotreating catalysts, including supported single/bimetallic catalysts, metal sulfide catalysts, metal oxide catalysts, metal carbide and nitride catalysts, are introduced by category, and their catalytic mechanism in the hydroprocessing of lipids is discussed. In addition, several major commercial production technologies and techno-economic evaluations for the production of bio-aviation fuel from lipids are introduced. Finally, major challenges and promising prospects are also pointed out for the future development of conversion of lipids to aviation fuels. HEFA-SPK (Hydroprocessed Esters and Fatty Acids Synthetic Paraffinic Kerosene) is an important type of sustainable aviation fuel (SAF) produced from lipids. This work carefully reviewed and summarized the properties of lipid feedstocks and pretreatment, hydrotreating catalysts, production processes and techno-economic evaluation. [Display omitted] • The properties of lipids and its pretreatment methods were introduced. • Hydrotreating catalysts of lipids were summarized by category. • Deoxygenation routes (HDO, DCN or DCX) of triglyceride depend on catalyst and reaction conditions. • Major commercial production technologies of jet fuel from lipids were introduced. [ABSTRACT FROM AUTHOR]

The share of renewable sources in energy production in Poland is increasing steadily, but the reliability of energy supplies is determined primarily by stable sources, i.e. the coal-fired power units now in operation. The paper compares the current energy mix of the Polish power generation system with other European countries, drawing attention to the dominant role of coal-fired sources in Poland. Recent-year changes in the structure of the energy system are presented, along with the changes planned to ensure reduction in carbon dioxide emissions. It is demonstrated that the planned changes in the energy mix will significantly deteriorate the level of reliability of energy supplies in subsequent years of transition. Variants are presented of necessary adjustments in the planned energy mix in the system, which will make it possible to meet the growing national demand for energy and ensure the required level of the energy system reliability. Several variants of the system expansion are considered, including gas-fired units, onshore and offshore wind farms, photovoltaic sources and a slower rate of decommissioning the coal-fired power units retrofitted with CO 2 capture facilities. The most favourable solution for the system reconstruction is to increase the share of all the above-mentioned energy sources. • Demand for power in the Polish energy system until 2035 was estimated. • Very low reliability of the planned power system has been demonstrated. • Reconstruction variants of the energy system, which increase its reliability, are given. [ABSTRACT FROM AUTHOR]

The city of Riga, currently updating their energy planning strategy for 2020–2030, surpassed the emission reduction target of the EU for 2030. Suitable targets for Riga are a reduction by 61% (2030) and 70% (2050), respectively, compared to 1990 levels. To achieve these objectives, this paper describes the research work defining pathways and measures in line with the planned actions of Riga, that focus on three thematic areas: green hydrogen, solar engagement, and modern transportation. The characterisation and comparison of the pathways is based on a graphical indicator method and weighting different factors accordingly to the Riga energy framework. The research done shows that production of green hydrogen is economically viable for Riga, achieving a Levelized Cost of Electricity of 0.0395 EUR/kWh and a Levelized Cost of Hydrogen of 3.67 EUR/kgH 2. Rooftop photovoltaic systems represent an appealing option for the citizens if a feed-in tariff of 0.1 EUR/kWh is awarded. As additional outcomes, this paper proposes alternative loan schemes such as voucher return packages that can foster citizen engagement in renewable projects and defines strategies to reduce road emissions that could include the development of microalgae carbon capture systems and the creation of a fossil-free last-mile delivery zone. • Identification of indicators and targets for a decarbonization strategy. • Competitive Levelized Cost of Hydrogen via wind power production increase. • Break even feed-in tariff for a growing rooftop PV systems adoption. • Solar potential map or alternative loan schemes fostering citizen engagement. • Implementing biological carbon capture and fossil-free last-mile delivery. [ABSTRACT FROM AUTHOR]

The chemical process industry is the second largest carbon-emitting sector in China. Therefore, it is extremely urgent and crucial to explore how to reduce carbon emissions in the sector. This paper employs the co-integration method and scenario analysis to investigate how to reduce carbon emissions in the sector. The granger causality test is conducted and the result indicates that all the variables except lnPare granger-causes lnCE. Moreover, comparing the JJ (Johansen-Juselius) co-integration with the EG (Engle-Granger) co-integration based on the squared residual, the fitting effect and the prediction effect, we find that the EG co-integration method is better. Furthermore, we adopt the EG co-integration and scenario analysis and find that the emission reduction potential of the sector will be 63.9 Mt in 2015 and 180 Mt in 2020 under the middle scenario; and 121.4 Mt in 2015 and 327.9 Mt in 2020 under the advanced scenario. Finally, the paper provides some policy implication. [ABSTRACT FROM AUTHOR]

Recently a great number of empirical research studies have been conducted on the relationship between certain indicators of environmental degradation and income. The EKC (Environmental Kuznets Curve) hypothesis has been tested for various types of environmental degradation. The EKC hypothesis states that the relationship between environmental degradation and income per capita takes the form of an inverted U shape. In this paper the EKC hypothesis was investigated with regards to the relationship between carbon emissions, income and energy consumption in 16 EU (European Union) countries. We conducted panel data analysis for the period of 1990–2008 by fixing the multicollinearity problem between the explanatory variables using their centered values. The main contribution of this paper is that the EKC hypothesis has been investigated by separating final energy consumption into renewable and fossil fuel energy consumption. Unfortunately, the inverted U-shape relationship (EKC) does not hold for carbon emissions in the 16 EU countries. The other important finding is that renewable energy consumption contributes around 1/2 less per unit of energy consumed than fossil energy consumption in terms of GHG (greenhouse gas) emissions in EU countries. This implies that a shift in energy consumption mix towards alternative renewable energy technologies might decrease the GHG emissions. [ABSTRACT FROM AUTHOR]

The iron and steel industry is one of the most energy-intensive industries, emitting 5% of the total anthropogenic carbon dioxide (CO 2). The control of CO 2 emissions has become increasingly stringent in the European Union (EU), resulting in EU allowance above 90 €/t CO2. Carbon capture will be required to achieve CO 2 emissions control, and carbon utilization via power-to-gas could significantly increase interest in carbon capture in the iron and steel sector. This paper presents a new concept that combines amine scrubbing with power-to-gas to reduce emissions in blast furnace-basic oxygen furnace steelmaking plants. Synthetic natural gas (SNG) is produced using green hydrogen from water electrolysis and CO 2 from steelmaking. The synthetic natural gas is later used as a reducing agent in the blast furnace, constantly recycling carbon in a closed loop and avoiding geological storage. The oxygen by-produced via electrolysis eliminates the necessity of an air separation unit. By applying these innovations to steelmaking, a reduction in CO 2 emissions of 9.4% is obtained with an energy penalty of 16.2 MJ/kg CO2 , and economic costs of 52 €/t HM or 283 €/t CO2. A sensitivity analysis with respect to electricity and the CO 2 allowances prices is also performed. • Novel power-to-gas and amine scrubbing integration proposed for BF-BOF steel making. • Detailed steel plant process model developed and validated. • Technical viability of the novel process concept demonstrated. • A reduction of 9.4% in CO 2 emissions has been achieved. • The novel concept would be profitable under 35 €/MWh and 177 €/tCO 2. [ABSTRACT FROM AUTHOR]

Abstract: Nowadays the control of greenhouse gas is probably the most challenging environmental policy issue. Since CO2 is considered the major greenhouse gas (GHG) that contributes to the global warming, enforcing technological strategies aiming to avoid or reuse CO2 emissions becomes crucial, in order to mitigate GHG environmental impact. Currently, solutions conventionally adopted to this purpose are carbon capture and storage (CCS) technologies. In this context, instead, the followed strategy aims to further improvements in energetic conversion efficiency with related reduced specific CO2 emissions (per produced kWhe). Therefore, with particular reference to the electric power generation, this paper proposes an innovative energy conversion system, based on solid oxide fuel cell (SOFC), characterized by higher efficiency and reduced CO2 emission factor respect to an analogous conventional energy plant. In particular, the innovative solution consists of combining SOFC to methane dry reforming technology, while the conventional system refers to steam methane reforming-SOFC coupling. The innovative system performance up to 65% electric efficiency as cited in the paper, was validated through simulations carried out in Aspen Plus environment. [Copyright &y& Elsevier]

Abstract: Research efforts to analyse China's future energy system increased tremendously over the past decade. One prominent research area is China's first binding CO2 emission intensity target per unit of GDP (Gross Domestic Product) and its impact on the country's economy and energy system. This paper compares 18 energy modelling tools from ten Chinese institutions. These models have been described in English language publications between 2005 and 2013, although not all are published in peer-reviewed journals. When comparing the results for three main energy system indicators across models, this paper finds that there are considerable ranges in the reference scenarios: (i) GDP is projected to grow by 630–840% from 2010 to 2050, (ii) energy demand could increase by 200–300% from 2010 to 2050, and (iii) CO2 emissions could rise by 160–250% from 2010 to 2050. Although the access to the modelling tools and the underlying data remains challenging, this study concludes that the Chinese perspective, independently from the modelling approach and institution, suggests a rather gradual and long-term transition towards a low carbon economy in China. Few reference scenarios include an emission peak or stabilisation period before 2040. While policy scenarios frequently suggest efficiency improvements, a short-term and large-scale introduction of non-fossil power technologies is rarely recommended. [Copyright &y& Elsevier]

Abstract: The variable electricity output of the RES (renewable energy sources) power plants, such as wind and hydropower, is an important challenge for the electricity system managers. This paper addresses the problem of an electricity system supported mainly on hydro, thermal, and wind power plants. A binary mixed integer non-linear optimization model with hourly time step is described. The model is applied to a system close to the Portuguese electricity case assuming demand forecasts for the year 2020. The main objective of this paper was to analyze the impact that different levels of installed wind power can have in the operation of this electricity system, taking into account the hourly and intra-annual variation of the renewable resources, the demand projections and also the technical restriction of thermal power plants. The results confirmed wind power as strategic technology to reduce both the marginal cost and CO2 emissions. According to the simulations run, wind power will not replace hydropower but a decrease of thermal power production is foreseen as more wind power is added to the system. Large wind power scenarios will particularly affect gas power plants performance, reducing both the load level and the number of operating hours. [Copyright &y& Elsevier]

Abstract: This paper explores the bi-directional long-run relationship between energy consumption in the road transport sector with CO2 emissions and economic growth in OECD countries. Using time series data from 1960 to 2008 and employing the Fully Modified Ordinary Least Squares cointegration approach, the paper shows positive significant long-run bi-directional relationship between CO2 emissions and economic growth, road sector energy consumption and economic growth and CO2 emissions and road sector energy consumption in all the OECD countries. To examine the response of each of the variables to shocks in the value of other variables, the generalized impulse response approach is employed. The response of CO2 emissions to economic growth is initially positive in most cases but it is relatively shorter when compared to its initial response to the road transport sector energy consumption. Moreover, in most cases, the response of carbon emissions to the road transport sector energy consumption lasts longer than its response to economic growth. This implies that most of the CO2 emissions from transport come from energy consumption, thus long-run policies related to the efficient use of energy and shifting to biofuel, renewable and nuclear energy can bring major benefits in mitigating GHG (Greenhouse Gas) emissions. [Copyright &y& Elsevier]

Abstract: Industry and fossil fuel combustion are the main sources for urban carbon emissions. Most studies focus on energy consumption emission reduction and energy efficiency improvement. Material saving is also important for carbon emission reduction from a lifecycle perspective. IS (Industrial symbiosis) and UrS (urban symbiosis) have been effective since both of them encourage byproduct exchange. However, quantitative carbon emission reduction evaluation on applying them is still lacking. Consequently, the purpose of this paper is to fill such a gap through a case study in Kawasaki Eco-town, Japan. A hybrid LCA model was employed to evaluate to the lifecycle carbon footprint. The results show that lifecycle carbon footprints with and without IS and UrS were 26.66 Mt CO2e and 30.92 Mt CO2e, respectively. The carbon emission efficiency was improved by 13.77% with the implementation of IS and UrS. The carbon emission reduction was mainly from “iron & steel” industry, cement industry and “paper making” industry, with figures of 2.76 Mt CO2e, 1.16 Mt CO2e and 0.34 Mt CO2e, respectively. Reuse of scrape steel, blast furnace slag and waste paper are all effective measures for promoting carbon emission reductions. Finally, policy implications on how to further promote IS and UrS are presented. [Copyright &y& Elsevier]

Abstract: Based on a traditional SOFC (solid oxide fuel cell) hybrid power system, three different SOFC hybrid power systems with zero-CO2 emission are proposed in this paper and their performances are analyzed and compared. The anode outlet gas of SOFC burns with the pure oxygen and the concentration of CO2 is greatly increased. In order to maintain the appropriate turbine inlet temperature, three different measures (steam injection, CO2 gas injection and heat exchange layout) are taken. Because the outlet flue gas of the afterburner mainly consists of CO2 and steam, the CO2 in the flue gas can be captured easily by the condensation method after the recovery of work and heat. With the exergy analysis method, this paper studies the exergy loss distributions of every unit of SOFC hybrid systems with CO2 capture and reveals the variation rules of exergy loss distributions. The effects of the main operating parameters on the overall performances of SOFC hybrid systems with CO2 capture are also investigated. The results show that the zero CO2 emission SOFC hybrid systems still have higher efficiencies, which only decrease about 3–4% compared with that of the basic SOFC hybrid system without CO2 capture. [Copyright &y& Elsevier]

Abstract: This paper investigates the economic feasibility of rice straw co-firing at coal power plants in Malaysia and in doing so looks at the operating, capital, and logistic costs. Co-firing rice straw in an existing coal power plant is a technique that could reduce CO2 emissions and make Malaysia less dependency on coal resources. In a country such as Malaysia with abundant biomass resources, utilizing biomass residue also would help reach government targets of developing renewable energy under the country's Fuel Diversification Policy. The overall rice straw life cycle assessment presented here analyses environmental, energy and economic aspects for co-firing of rice straw at existing coal power plants in Malaysia. Analysis of GHG emissions and energy consumption throughout the entire co-firing rice straw life cycle was based on selected coal power plant capacity output. This paper also analyses the implication of rice straw use under different co-fired ratios, transportation systems and CO2 emission prices. The reduction of GHG emissions was found to be significant even at a lower co-firing ratio. [Copyright &y& Elsevier]

Abstract: The present paper is focused on the optimization of combined heat and power distributed generation systems. In particular, the authors describe a mixed-integer linear programming model that has been developed in order to optimally design and operate an energy system in a limited urban area where buildings are equipped with small-size CHP plants and are connected by a heat distribution network; in the proposed model a multi-objective function is optimized, since capital and operating costs, as well as CO2 emissions, are taken into account. The model has a general validity even if the results reported in the present paper are relative to the case study represented by a residential and tertiary district in the city of Arenzano in the North of Italy. Furthermore, a comparative study has been done in order to quantify the benefits, in terms of economic saving and CO2 emission reduction, of having a combined heat and power distributed generation system in buildings in spite of using boilers to produce heat and of buying electricity from the grid. [Copyright &y& Elsevier]

Abstract: The paper's objective is to suggest a model for determining optimal lifetime of passenger car based on minimization of CO2 emission. The life cycle was modeled by eight main life cycle sequences. Combining the mathematical interpretations of the itch life cycle sequence is developed an optimization model. In this paper is suggested a new mathematical interpretation of following sequences: use, repair, distribution of passenger car and distribution of passenger car's parts. Comparison of the obtained numerical results was performed on examples for the data of new passenger car fleet from the EU14 countries. Special attention is given to analysis of dependencies between the optimal lifetime of passenger cars and Directive 2000/53/EC, trends of changing car weight, model year, kilometer driven and regulatory limit of the specific CO2 emission. The optimal lifetime in case where petrol car is replaced by diesel car was analyzed too. [Copyright &y& Elsevier]

Abstract: Generation expansion planning is defined as the problem of finding the technology type, number of generation units, size, and location of candidate plants within the planning horizon. In the deregulated environment rather than the traditional system which considered the cost minimization as the main objective function in generation expansion planning problem, the major objective is to maximize the Project Lifetime Economic Return. In this paper, the problem is solved considering three objectives, simultaneously (i.e. maximization of the Project Lifetime Economic Return, minimization of CO2 emission, and minimization of the fuel price risk due to the use of non-renewable energy sources). Furthermore, due to the extensive use of renewable energy sources, e.g., onshore wind, offshore wind, solar, etc, the effect of these power plants has been investigated in this paper. In order to make the problem more compatible with the real world, some of the most common incentive systems (i.e. carbon tax, emission trade, quota obligation, and feed-in-tariff) have been considered for the problem formulation. The problem is solved using Modified Normal Boundary Intersection method using General Algebraic Modelling System. Finally, a case study is designed to assess the efficiency of the proposed scheme. [Copyright &y& Elsevier]

Abstract: Nowadays, the large and small districts are proposing a new city model, called “the smart city”, which represents a community of average technology size, interconnected and sustainable, comfortable, attractive and secure. The landscape requirements and the solutions to local problems are the critical factors. The cities consume 75% of worldwide energy production and generate 80% of CO2 emissions. Thus, a sustainable urban model, “the smart city”, is sustained by the European Commission. In this paper, a model for computing “the smart city” indices is proposed. The chosen indicators are not homogeneous, and contain high amount of information. The paper deals with the computation of assigned weights for the considered indicators. The proposed approach uses a procedure based on fuzzy logic and defines a model that allows us to estimate “the smart city”, in order to access European funding. The proposed innovative system results in a more extended comprehension and simple use. Thus, the model could help in policy making process as starting point of discussion between stakeholders, as well as citizens in final decision of adoption measures and best evaluated options. [Copyright &y& Elsevier]

Abstract: In this paper, a PV/Wind integrated hybrid power energy system is analyzed using the dynamical simulation method. The market for the distributed power generation based on renewable energy is increasing, particularly for the standalone mini-grid applications. The main design components of PV/Wind hybrid system are the PV panels and the wind turbine. The case study is realized using the meteorological data for a Typical Metrological Year (TMY) for the city of Belgrade, in Serbia. The dynamical analysis is based on the transient system simulation program TRNSYS 16. The purpose of the study is to design a realistic energy system that maximizes the use of renewable energy and minimizes the use of fossil fuels. The reduction in the CO2 emissions is also analyzed in the paper. [Copyright &y& Elsevier]

Abstract: Using energy systems analysis, we examine the potential to reduce CO2 emissions and oil use by integrating motor biofuel production with pulp mills. BLG-DME (black liquor gasification with di-methyl ether production) is compared with solid biomass gasification with BIG-FT (solid biomass gasification with Fischer-Tropsch fuel production). The studied systems are expanded with stand-alone production of biomass-based electricity and motor fuel so that they yield the same functional unit in terms of motor fuel and electricity as well as pulp or paper product, in order to facilitate comparison. More motor biofuel can be produced in integration with the studied mills with BLG-DME than with BIG-FT because the black liquor flow is large compared with other fuel streams in the mill and the integration potential for BIG-FT is limited by the mill’s heat demand. When both systems are required to produce the same functional unit, the BLG-DME system achieves higher system efficiency and larger reductions in CO2 emissions and oil use per unit of biomass consumed. In general, integration of motor biofuel production with a pulp mill is more efficient than stand-alone motor biofuel production. Larger reductions in CO2 emissions or oil use can, however, be achieved if biomass replaces coal or oil in stationary applications. [Copyright &y& Elsevier]

In this paper, the methods of the integration of a supercritical coal-fired power plant with membrane CCS installation are shown. In addition to membrane modules, the CCS installation also consists of two vacuum pumps and two CO2 compressors. In this paper, the relationship between the auxiliary power required to drive these machines and the recoverable amount of heat is shown. This relationship is the reason for the integration of the supercritical coal unit with the CCS installation, which is used for cooling compressed CO2 in the CCS installation by use of condensate (or feed water) from the supercritical coal unit cycle. This cooling process causes both a reduction of the auxiliary power required to drive the compressors and vacuum pumps and increase of power ratio of a steam turbine. In this paper, the optimisation method for minimising the decrease of overall efficiency of the power plant connected with its integration with CCS installation is shown. This results in choosing the optimal pressure ratios in the applied compressors and vacuum pumps under the condition of sufficient heat transmission to the steam turbine cycle. For investigated units, the cost of CO2 emission avoidance and the break-even price of electricity were also calculated. [Copyright &y& Elsevier]

Abstract: Uganda’s electricity sector for long has been depending on hydro as a base power source. Diesel is currently the second source of electricity which supplements the hydro power. The use of diesel has some implications; first, the price of fuel is high and therefore the energy produced is also expensive. Secondly, diesel power would not be a better option because of its immediate and long term effect on environment due to carbon emission and other pollutants that are often injected into atmosphere from diesel. This paper therefore examines the possibility of using solar PV systems as alternative to diesel as a source of electricity. The paper has also established that the tendency of depending on non-renewable sources of electricity can be minimized and at the same time reducing the cost of energy in the future. [Copyright &y& Elsevier]

Abstract This paper presents a combined analytical and experimental study of an innovative multiple-throughout-flowing micro-channel-panels-array applicable to a solar-powered rural house space heating system. This array, compared to the traditional one-to-one-connection panels-array, can significantly reduce the temperature difference between the head and real panels and thus increase the overall solar thermal efficiency and energy efficiency ratio (EER). The research methodology covers the theoretical analysis, experimental testing, model validation and system optimization. It is found that the analytical model has a good accuracy in predicting the performance of the multiple-throughout-flow micro-channels-panels-array, giving a discrepancy of less than 10%. In terms of the configuration and sizes of the array, 10 pieces of panels with 5 flow turns is regarded as the most favorite option. During the operation, decreasing flow rate of the fluid led to the increased EER of the panels-array. By converting the one-to-one-connection mode into the multiple-throughout-flowing mode, the overall solar thermal efficiency of the panels-array increases by around 10% and its energy efficiency factor (EER) decreases by 80% respectively. The research has addressed a novel solar-panels-array that can be well applied to solar thermal systems, thus making a significant contribution to the saving of fossil fuel energy consumption and reduction of carbon emission on global scale. Highlights • Multiple-throughout-flow lowers temperature difference between head and rear panels. • This flow mode leads to the increased overall solar thermal efficiency by around 10%. • This flow mode leads to the increased energy efficiency factor by around 80%. • The most appropriate panel number in an array is 10. • The most appropriate fluid flow turning number is 5. [ABSTRACT FROM AUTHOR]