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Paper mulberry, a fast-growing and vigorous plant, is a potential substrate for producing lignocellulosic bioethanol and an important renewable alternative to fossil fuels. In order to improve the economic feasibility of ethanol production from paper mulberry, H 3 PO 4 /H 2 O 2 pretreatment was selected as the most suitable pretreatment method that could produce the highest glucose concentration (131 g/L) compared with other pretreatments (73.2–89.3 g/L) at high solid loading. Whereafter, the final solid loading of H 3 PO 4 /H 2 O 2 pretreatment was significantly increased to 40% (w/v) without any decrease in the final glucose concentration. Finally, a novel Fed-nonisothermal-simultaneous saccharification and fermentation was constructed using H 3 PO 4 /H 2 O 2 pretreated paper mulberry, which bypassed the inhibition caused by paper mulberry solid and high temperature on the traditional simultaneous saccharification and fermentation, improving ethanol concentration (63.9 g/L), ethanol productivity (1.33 g/L/h) and ethanol yield (0.160 g/g-biomass) by 30.4%, 30.4% and 30.1%, respectively, compared to those obtained from SSF (simultaneous saccharification and fermentation) process. Thus, we have opened up a novel way to produce ethanol or other biofuels using the paper mulberry as an outstanding alternative substrate. • We are the first to produce ethanol from paper mulberry. • An extremely high solid loading (40%) was used in the pretreatment process. • A novel Fed-nonisothermal-SSF was developed, improving ethanol yield by 30.1%. [ABSTRACT FROM AUTHOR]

Waste terpenes from paper industry, pine resin tapping or citric industry are abundant feedstocks that can be used as components in diesel blends. However, terpenes such as turpentine or orange oil are highly reactive, tend to form deposits and show high sooting tendency. These drawbacks can be solved with hydrogenation, which reduces the degree of unsaturation of the molecule and thus, the formation of soot. In this work, blends at 20 vol % of hydrogenated turpentine and hydrogenated orange oil in diesel fuel were tested in a Euro 6 diesel engine following Worldwide harmonized Light-duty Test Cycle (WLTC). Engine performance, gaseous and particle matter emissions and combustion analysis from these blends were compared with those from diesel fuel. Engine performance was similar for all fuels, with slight differences in equivalence ratio and exhaust gas recirculation (EGR) rate. CO and HC emissions were increased whereas NOx emissions remained constant when blends were tested, with respect to diesel. Sooting tendency was improved since particle mass emissions were reduced despite the particle number emissions were similar to those from diesel. Combustion was quite similar between all fuels and only ignition delay was longer and combustion velocity higher for blends in comparison with diesel. • Blends with 20% hydrogenated terpenes can be used without penalty in emissions. • HC and CO emissions were higher due to high volatility of blends. • Nitrogen oxides emissions were similar to diesel. • Particle mass emissions were reduced despite increasing in number. • Molecular cycles greatly affect particle nucleation. [ABSTRACT FROM AUTHOR]

During the last 10 years Brazil has accelerated the incorporation of new wind capacity into its power matrix. This situation has generated the need for increased transport capacity. However, there have been delays in the planning process for new transmission line construction, thus inducing trapped electricity in the system; in other words, electricity that cannot be dispatched to the interconnected system. Using system dynamics modelling, this paper assesses energy policy alternatives for improving the synchronisation between the construction of both power generation and transmission capacities. Simulation results show that policy synchronisation within the wind industry may provide important opportunities regarding security of supply. This paper concludes that in Brazil's case it is possible to attain a balance between wind power expansion and interconnection capacity through synchronised and systemic interventions. • Power systems require a sustainable balance between supply and demand. • Wind power industry could be affected by energy policy fragmentation. • This article assesses alternative policy options to contribute to the existing literature on grid congestion. • New insights on the synchronisation of energy policies for the wind industry expansion is offered. [ABSTRACT FROM AUTHOR]

The paper investigates the role of renewable energy and alternative and nuclear energy in mitigating CO 2 emissions. Trade openness is added to consider its effect on the environment, as it appears to be a crucial factor in interregional cooperation and development. We adopt a sample of nine signatories to the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) from 1971 to 2014. Various time-series econometric methods are utilized including two long-run estimators - fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) - and a Granger-causality test. Several noteworthy findings are achieved from this paper. First , the inverse U-shaped relationship is found in six countries: Australia, Canada, Chile, New Zealand, Peru and Vietnam. The U-shaped relationship is found in Japan and Malaysia whereas no evidence is observed in Mexico. Second , the adoption of either renewable energy or alternative and nuclear energy would mitigate CO 2 emissions and trade openness plays an important role in facilitating this effect. Third , the directions of Granger causality among the variables of interests including consumption of renewable energy; consumption of alternative and nuclear energy, trade openness and CO 2 emissions, do vary across countries and between the short term and the long term. • Inverse U-shaped relationship in Australia, Canada, Chile, New Zealand, Peru, Vietnam. • U-shaped relationship in Japan and Malaysia and no evidence in Mexico. • Consumption of renewable energy, alternative & nuclear energy reducing CO 2 emissions. [ABSTRACT FROM AUTHOR]

This paper focuses on hybrid renewable energy systems (HRES) as an alternative for conventional energy systems, especially fossil fuels. The problem is to find the optimal number of components of a standalone hybrid system, based on minimizing the value of the annualized cost of the system (ACS), in the presence of the constraints. To reduce the CO2 particles as one of the most threatening particles for the planet, an additional constraint is added to the objective function. For solving the problem of system sizing, Harmony Search and Ring Theory-based Evolutionary Algorithm have drawn attention to be preferred to numerous techniques. In addition,a combination of both, which has never been used before, is proposed. The proposed hybrid algorithm shows its ability to mitigate both the emissions and costs of the system promisingly in comparison with the others. Clearly, with Carbond = 15 and different values of LPSPMax as well as using RTHS, RTEA and HS algorithms for PV/WT/BSS/DG configuration, the best performance in terms of ACS minimization belongs to RTHS algorithm with the minimum cost of $1528.2. Also, considering LPSP = 0 and changing carbon from 0 to 20 tons/year, the ACS of the PV/WT/BSS/DG configuration is reduced from $38586.3 to $21153.5 (45% reduction). • Using a hybrid algorithm called RTHS to minimize the annual costs of the system. • Considering the LPSP constraint to supply the load demand at an acceptant level. • Reducing CO 2 emissions to increase the renewables penetration. • Considering uncertainty on both the generation and demand sides. • Validating of the proposed method based on real data for a case study in Iran.. [ABSTRACT FROM AUTHOR]

Bio-butanol (N-butanol) is a renewable, environmentally friendly, and economical alternative fuel that, like many other alternative fuels such as methanol, ethanol, and natural gas, is also considered to be one of the most advantageous fuels to replacement for conventional petroleum fuels (such as gasoline or diesel fuel). Bio-butanol fuel has recently been used as an alternative fuel to conventional fuels for IC engines (gasoline or diesel engines) to meet some environmental and economic considerations. Compared with conventional fuels (gasoline and diesel fuels), bio-butanol has many advantages, so it has the potential to reduce vehicle emissions, thereby improving the atmospheric environment, reducing energy demand pressure, and significantly decreasing the car's dependence on non-renewable resource. The research and application of bio-butanol have made great progress in the past few years, so it is worth to summarize and analyze the application of bio-butanol in IC engines. This paper systematically introduces the application of bio-butanol fuel in SI and CI engines, and summarizes the application methods of bio-butanol/gasoline, bio-butanol/diesel and other mixed fuels on SI and CI engines. Finally, some suggestions for the future research and development direction of bio-butanol engines are put forward in study. • The production methods, marketing and the properties of bio-butanol were summarized. • In SI and CI engines, bio-butanol has a position effect on fuel consumption and emissions. • At present, the bio-butanol mixed combustion method is widely used in SI and CI engines. • This paper put forward some new suggestions in the researches of bio-butanol engine in the future. • To meet environmental and energy balance considerations, bio-butanol has a bright future in SI and CI engines. [ABSTRACT FROM AUTHOR]

As an alternative energy for fossil fuels, geothermal reserve is abundant. In recent years, scholars have investigated geothermal wells through numerical simulations. To the best of our knowledge, many studies have explored the influence factors of thermal power over time, and few studies have investigated the heat transfer mechanism between wellbore and formation in different circumstances. This paper aims to established a transient numerical heat transfer model of U-shaped closed-loop geothermal system with long horizontal section, which can simulate the temperature distribution and heat transfer mechanism during the whole wellbore formation. In the model, the convection term is discretized by using the second-order upwind scheme, and the finite volume method is used to solve it. The numerical results are proven to be correct by comparing with the field data of a well in China. Subsequently, the influence mechanism of fluid type, insulation casing length, fluid injection temperature, flow rate, and horizontal section length on thermal power is explored. The optimal depth of insulation casing under different injection temperatures, flow rates, and horizontal section lengths is suggested so as to provide crucial guidance for engineering practice. [ABSTRACT FROM AUTHOR]

Abstract European Union legislation in the form of the Renewable Energy Directive 2009/28/EC and the Deployment of Alternative Fuels Infrastructure Directive 2014/94/EC have placed mandatory requirements on Member States to deliver sustainable forms of alternative transport infrastructure in order to reduce greenhouse gas emissions in the transport sector. However, there is currently little or no refuelling infrastructure to support the development of an alternative transport fuel market for compressed natural gas and its renewable form biomethane in a number of EU Member States. Primarily focussing on a combination of biomethane and compressed natural gas (bio-CNG), this paper analyses the key considerations to develop a strategic infrastructure framework for bio-CNG and defines the criteria for the placement of public access refuelling stations in order to satisfy legislative requirements, commercial considerations, strategic placement and natural gas network infrastructure utilisation. This paper devises a strategic infrastructure framework on which a national public access refuelling network for bio-CNG could be provided for Ireland as a template and for other Member States with similar infrastructure and renewable requirements to follow. The framework includes the provision of 22 bio-CNG refuelling installations in strategic locations across the country. Highlights • Proposes criteria to develop a bio-CNG infrastructure framework in Ireland. • Devises a bio-CNG infrastructure framework to influence Irish transport policy. • Proposes 22 bio-CNG refuelling station locations to initiate the Irish market. • Nine stations are located in areas with high biomethane production potential. • This framework complies with the EU Alternative Fuels Infrastructure Directive. [ABSTRACT FROM AUTHOR]

Abstract This paper aimed at identifying the factors that influence truck fleets' willingness to purchase alternative fuel vehicles (AFVs) in China. An investigation was conducted in Jiangsu province to evaluate the truck fleets' characteristics and preferences by structured questionnaire survey of 288 truck fleets. By establishing logistic regression models, this paper analyzed the factors that influence the willingness of truck fleets to purchase AFVs, their purchase time and their acceptable price. Policy recommendations on improving AFVs market based on survey results and current policies in China are proposed. These findings provide significant insights into truck fleets' demand for AFVs and contribute to the promotion of AFVs implementation in Chinese road freight industry. Highlights • Logistic regression models on truck fleets' preference on AFVs, their purchase time and their acceptable price. • Estimation based on truck fleets' stated choice in Jiangsu province, China. • Policy recommendations on improving AFVs market based on survey results and current policies in China. [ABSTRACT FROM AUTHOR]

Although renewable energy has been emphasized to mitigate carbon emissions, energy policies may require rearrangement. This paper aims to suggest the possibility of needs in energy policy rearrangement by revealing if the mitigation impact of the renewable energy supply has been diminished with a case study on Organization for Economic Cooperation and Development (OECD) countries. Adopting the idea of the environmental Kuznets curve hypothesis, the study investigates the nonlinear relationship between the renewable energy supply and carbon emissions. We collected the longest panel data possible for 34 OECD countries from 1971 to 2019. While the cointegrating equation results suggest that renewable energy has contributed to carbon mitigation, nonlinear estimation and quantile regression propose that the marginal mitigation impact from renewable energy might be weakening. 1% increase in renewable energy supply and the share of renewable in energy mix has mitigated carbon emissions by 0.134% and 1.260%, respectively. The empirical results insist that policymakers discover alternatives to decarbonize the energy sector, other than renewable energy expansion. Options to achieve carbon neutrality include heat expansion via unused heat, that is, national energy system innovation towards wasted energy utilization. [ABSTRACT FROM AUTHOR]

The benefits of biomass as an alternative fossil fuel can be realized mainly through biomass consumption. This paper examines the growth rate and spatial patterns of biomass consumption in the United States (hereafter US) during the period 2000–2012, using the SLOPE index, Moran's I and local Moran's I. Results indicate that US States show either slow growth or slow decline in biomass consumption during the period 2000–2012. The number of States that have slow growth in biomass consumption is slightly larger than the number of States showing slow decline. The pattern of growth rate of biomass consumption revealed by the SLOPE index and the observed pattern of the temporal variation of biomass consumption ensures that the SLOPE index can catch the growth rate of biomass consumption. This pattern does not align with the increased annual investment in biomass, indicating that the investment in biomass does not flow down to the biomass industry effectively. The pattern of growth rate of biomass consumption will provide additional evidence for the debates about the effectiveness of State renewable energy policy, and demonstrates an urgent need for appropriate State renewable energy policies. There is a High-High spatial cluster around the Southeast of the US and a Low-Low spatial cluster in the Middle of the US in 2000, 2004, 2008 and 2012. The regional spatial cluster in biomass consumption has somewhat relationship with the growth rate of biomass consumption, which can help the understanding of the growth rate of biomass consumption. • The SLOPE index is used to investigate the growth rate of biomass consumption. • The pattern of growth rate does not align with the increased annual investment. • There is an urgent need for appropriate State renewable energy policies. • There are regional clusters in biomass consumption in 2000, 2004, 2008 and 2012. • The regional spatial cluster has somewhat relationship with the growth rate. [ABSTRACT FROM AUTHOR]

In this paper, conventional and renewable energy sources for sustainable development of energy sector in India are evaluated from multiple perspectives including economic, technical, social, environmental, political, and flexible criteria. An integrated Shannon's entropy multi-criteria decision making (MCDM) method has been used for the evaluation and assessment of these sources. Thermal, gas, nuclear, solar, wind, biomass, and hydro energy options are used as the alternatives in the decision model. Shannon's entropy method is applied to determine the weights of decision criteria, and fuzzy analytical hierarchy process (AHP) method is applied to prioritize sustainable energy alternatives. The output of the proposed model was compared with six different fuzzy MCDM techniques for the establishment of correlation index. Solar energy was shown to be particularly well suited for India followed by wind and hydro energy sources. Later, the study has developed fourteen scenarios, considering the first five sustainable energy sources (solar, wind, hydro, biomass, and gas power), to evaluate the optimal energy mix scenario for the sustainable development of energy sector in India. An optimal energy mix scenario carries the heroic development of solar, wind, and hydro energy with cross border import-export facility for the time frame of the year 2030. • Reviewed the overview, challenges and development of Indian energy sector. • Developed integrated Shannon entropy fuzzy MCDM approach. • Evaluated the most sustainable energy alternatives in India. • Results validated with six fuzzy MCDM approaches and correlation coefficients. • Evaluated the optimal energy mix scenario in India for the time frame of 2030. [ABSTRACT FROM AUTHOR]

The 100-years-old model of centralized generation and one-way power flow is being disrupted by alternative energy technologies that enable customers to generate their own electricity. The massification of distributed generation (DG) started lately in Brazil, but it growth fast in capacity since then. The electric utilities have presented technical and economical challenges arising from the increased diffusion rate of DG. Due to lack of studies addressing performance metrics suitable for this scenario, this paper proposes a measurement system for determination of the overall performance index of electric utilities related to DG services. The methodology has been developed based on Delphi method and Balanced Scorecards to define 32 objectives. Analytic Hierarchy Process concepts was applied for weighing objectives perspectives and to derive an overall performance index. Overall performance indexes related to DG found from application of proposed model in all companies were lower then 50%. No one of the evaluated companies achieved a regular or satisfactory performance. This result confirmes that electric utilities companies are far from reaching expected satisfaction factors related to DG services. The introduced methodology can be used by the scientific community and policy-makers of any country to better inform to a new energy distribution and generation scenario. • A performance measurement system with multicriteria decision methods BSC-AHP. • A methodology that is easily replicable by researchers from other countries. • In Brazil, no electric utility is at an advanced organizational level index of DG. • Organizational management of the distributed generation in electric utilities. [ABSTRACT FROM AUTHOR]

In order to accelerate the transition from carbon fuels to renewable energy sources, it is essential to extend our knowledge of the resources' availability to further improve or adjust the design of extraction devices. In the present paper, a first characterization of the tidal stream resource along the coast of The Netherlands is performed using a high-resolution unstructured grid implementation of the Thetis model. Extensive validation of the sea surface elevations was done by comparing with existing networks of tide gauges in the North Sea. The simulations from this study show that the highest tidal current intensities are generated mainly at Den Helder and Oost Vlieland, reaching values > 1.5 m s − 1 and power density estimates that are most frequently close to 300 W m − 2 and that can reach values ≥ 900 W m − 2 . Given the relatively reduced depths where these "hot spots" are found, most existing stream turbines will require further development to operate. Nevertheless, the existence of higher current intensities zones, along a commonly considered "low energy" coast, opens the door to include the tidal stream resource in near future plans to diversify the energy supply in The Netherlands. [Display omitted] • First tidal stream resource assessment for The Netherlands. • Identification of high energy sites for potential extraction. • Investigation on the persistence and magnitude of Dutch "hot-spots". [ABSTRACT FROM AUTHOR]

Wind energy has become a kind of attractive alternative energy in power generation field due to its nonpolluting and renewable properties. Wind speed forecasting acts an important role in programming and operation of power systems. However, achieving high precision wind speed forecasts is still consider as an arduous and challenging issue with the randomization and transient exist in wind speed time series. For this reason, this paper proposed two novel de-noising-reconstruction-based hybrid models which consist of novel signal decomposed methods, feature selection approaches and predictors based on quantile regression and optimization algorithm to achieve more accurate short term wind speed forecasting. The developed hybrid models firstly eliminate inherent noise from the wind speed sequences via decomposed method and subsequently construct the appropriate datasets for the forecasting engines by adopting the feature selection method; finally, establish the predictors for the forecasting task. To verify the effectiveness of proposed forecasting models, 1-h and 2-h wind speed data collected from Yumen, Gansu province of China mainland is used as case studies. The computational results demonstrated that the developed hybrid models yield better performance contrast with those of other models involved in this research in terms of both wind speed deterministic and probabilistic forecasting. • Two hybrid strategies with four modules are developed for wind speed forecasting. • A modified signal decomposition method is proposed for wind speed noise reduction. • A novel correlation-analysis-based approach is proposed to feature selection. • The proposed QRNN-based model can obtain forecasting results in different quantile. • The hybrid models perform well in both deterministic and probabilistic forecasting. [ABSTRACT FROM AUTHOR]

Chemical energy storage in the form of hydrogen is playing an important role in the synthesis of alternative energy carriers such as Synthetic Natural Gas (SNG), Methanol and Dimethyl ether (DME) supplementing with a carbon source. The only renewable carbon source is biomass, which is a limited resource. However, the addition of hydrogen could potentially extend the existing biomass resources. This paper describes the modeling of a novel combined Solid Oxide Electrolysis Cell (SOEC) and oxygen blown biomass gasification system using Aspen Plus. One of the advantages of using such a combined system is the use of oxygen for gasification and reforming. The comparison of reforming technologies showed that an autothermal reformer (ATR) could be an advantage since oxygen is already available from the electrolysis stack and the ATR produced syngas has a higher CO/CO 2 ratio, which increases the methanol synthesis's reaction rate. ATR requires much less energy ∼13 MW for almost complete methane conversion compared to ∼35 MW for Steam Reforming (SR). The advantage of using inter-cooled compression upstream or downstream for such a combined process has been explained. A methanol thermal conversion efficiency of 72.08% can be achieved for gasification and SOEC combined system compared to 55.7% for an only gasifier system. • Higher Efficiency for the proposed combined system compared to biomass alone. • Better utilization of O 2 (Electrolysis by-product). • Auto-thermal reforming has advantage over steam reforming for such combined system. • Increases biomass productivity by more than 100%, saving limited carbon resource. • Excess heat can be used for Electrolysis hence better system efficiency. [ABSTRACT FROM AUTHOR]

Health centers and hospitals can be categorized as one of the major consumers of electrical energy in building sectors. Due to their competitive environment, they need to decrease their costs, including energy costs. On the other hand, environmental problems, lack of fossil fuels, and high energy consumption lead to using alternative energy generation methods like renewable energy sources (RESs). In this paper, we consider that the hospital can produce part of its energy from RESs for cost reduction and we implement demand dispatch energy program for using RESs efficiently. The challenge is that the main goal of hospital is providing health services not energy cost reduction. Therefore, we present a bi-objective formulation for using RESs in hospitals in a way to minimize costs and dissatisfaction by scheduling the activities of the hospital by considering hospital's specific constraints and limitations. With the help of the proposed model, hospitals will decrease energy costs while maintaining comfort of patients and surgeons at the same time. The model is solved using real data of a hospital in Iran, and sensitivity analysis on different parameters is done. The proposed model will cause reduction in energy cost of the hospital by implementing demand dispatch program for using RESs in the hospital. • Health centers are considered as a new type of energy consumers. • Wind turbines and solar panels are used for energy generation in hospitals. • Activities are scheduled in a way to minimize the cost and the dissatisfaction of patients and surgeons. • The limitations of hospitals are considered in the mathematical model. • The proposed model reduces energy use in peak hours and shifts the loads to time periods with renewable energy generation. [ABSTRACT FROM AUTHOR]

The growing demand for energy raw materials and the ongoing implementation of restrictions on emissions of pollutants have caused considerable intensification of research on alternative fuels. Among them, syngas seems to be an especially promising option to use for electricity generation. Due to the fact that syngas is mainly composed of hydrogen and carbon monoxide, which are both flammable gases and the latter of which is also toxic, its uncontrolled release can pose a serious hazard. The paper presents the processes involved in syngas production from coal and biomass with respect to the produced gas composition. An analysis is carried out of potential effects of a syngas release from the pipeline to the environment, such as a jet fire, an explosion and formation of a toxic gas cloud. Hazard zones arising around a damaged synthesis gas pipeline are determined. The size of the zones depends on the gas composition and is generally much smaller in the case of a release of syngas obtained from biomass gasification. It also depends on the degree of damage to the pipeline. The created hazard zone is the biggest if the pipeline is ruptured completely. • The safety zones around syngas pipeline are defined. • The dependence of the syngas cloud range on the degree of pipeline damage are shown. • The comparative analysis of the risks poses by syngas from coal and biomass was made. [ABSTRACT FROM AUTHOR]

N-butanol is a valuable renewable fuel that has been extensively studied. In this paper, the effect of n-butanol-gasoline blends on combustion and emissions performance of direct injection gasoline engine under urban conditions (throttle opening is 10% and 35%) is studied by using GT-Power simulation software. By comparing the several fuels, we find a fuel that is more suitable for the engine to operate in urban conditions. This is of great significance for reducing China's dependence on oil. The simulation results show that adding n-butanol into gasoline can significantly reduce the peak in-cylinder temperature (T max), improve the brake thermal efficiency (BTE) of the engine. It is advantageous for the engine to operate under urban conditions. By comparison, it is found that Bu40 is the most suitable fuel. When the throttle opening is 10%, high engine speed operation will reduce brake power (BP), brake torque (BT) and BTE, and increase CO emissions. In terms of emissions, n-butanol gasoline blends can reduce CO and NO x emissions, but HC emissions increase. Finally, the results show that n-butanol-gasoline blends can be used in SI direct injection gasoline engine instead of pure gasoline. • The Bu40 can improve the performance of the engine and has the potential to be a fuel alternative to gasoline. • The n-butanol gasoline blends can increase engine power and torque at low speeds. The result is the opposite at high speeds. • N-butanol gasoline blends can improve engine thermal efficiency. • N-butanol gasoline blends can reduce CO and NO x emissions, but increase HC emissions. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the potential of renewable energies utilization in detail through three in-house developed strategies to increase the renewable power generation share until the year 2050 assuming either an optimistic 100% or a practical 50% based on the national policies. Solar, wind, and waste energy are the most feasible alternative energy resources in Iran. In the first strategy, power plants are phased out according to their lifetime and replaced by renewable resources in 5-year time steps. The second strategy employs a 3% replacement rate to reach a 100% renewable power generation in 2050. In the third strategy, the national plan of the power ministry is utilized to adopt a more practical pathway for increasing the renewable power generation share up to 50%. Pollution and water shortage crises are also considered within the framework of this study. The following work can lay the foundation for future studies of its kind in Iran as well as other countries all over the world. Developing the presented results can lead to the practical implementation of the study, which will vastly benefit the residents. Moreover, it will provide a great investment opportunity for foreign and domestic companies working on the field. Highlights • Approach applied to renewable penetration in the power system of Iran. • Three strategies are proposed for transition to 100% renewable. • The storage cost for three scenarios for the year 2050 are calculated. • The storage problem was addressed for various regions of the country. [ABSTRACT FROM AUTHOR]

Abstract In engine tests where the feasibility of alternative fuels is being investigated, the results of the engine performance, combustion characteristics, and exhaust emissions should be considered as a whole. It is difficult to determine the optimal parameters due to a large number of results obtained in multi-variable experiments. Multi-criteria decision making (MCDM) methods are preferred in solving such problems to energy management and energy efficiency. This paper deals with an application of a novel hybrid MCDM technique is suggested to select the optimum fuel for the compression ignition (CI). Five academicians who are an expert in the field of CI engines are selected to set criteria in the MCDM. Engine tests carried out at the constant engine speed and the resistive load of 10.8 kW in the generator-engine set. The results were used in the MCDM process. In this study, the hybrid models which are SWARA-MOORA, and ANP-MOORA has been preferred as the MCDM methods. The best fuel choice was made from fuels such as animal fat biodiesel (AFB), vegetable oil biodiesel (VOB), diesel fuel and the blend fuels. According to results, it was determined that the best fuel is VOB20 in both hybrid methods according to the determined criteria. Graphical abstract Image 1 Highlights • The pure vegetable oil, animal fat biodiesels and their blend with diesel were used as fuel in the CI engine. • The engine tests were conducted at the constant engine speed and load. • The best fuel choice for optimum operating conditions was made using multi-criteria decision making (MCDM) methods. • ANP-MULTIMOORA and SWARA-MULTIMOORA hybrid models have been preferred as MCDM methods. • In both methods, VOB20 was identified as the best fuel. [ABSTRACT FROM AUTHOR]

Abstract: The oil crisis and the global effort to control the greenhouse effect have forced the researchers to think of various alternative energy sources. This decade has seen increasing importance of chemically treated vegetable oil biodiesel fuels for various applications in heat engines. Post-Kyoto negotiations refer to high level talks attempting to address global warming by limiting greenhouse gas emissions. During Climate Change Conference in Copenhagen the potential topics discussed were carbon capture and storage, biofuels, adaptation financing, technology transfer, sustainable agriculture, emissions targets, tropical forests and rural and transport electrification. Our area of interest is biofuels under which nonedible Jatropha oil due to its properties which are very close to diesel fuel is being explored as an alternative fuel. A lot of research is underway in the use of different biodiesel fuels in Internal Combustion engines, but very limited work has been reported in its use in gas turbines. This paper describes the results of an ongoing development program aimed at determining the technical feasibility of utilizing biodiesel in IS/60 Rovers gas turbine. The test rig is equipped with a dynamometer for turbine loading and AVL exhaust gas analyzer has been used to record emissions. The test results of 2 blends have been reported in this paper. Analyzing the results compared with the base line performance using diesel fuel under normal conditions show encouraging outcomes. [Copyright &y& Elsevier]

Abstract: This paper presents a multi-agent (MAS) solution to energy management in a distributed hybrid renewable energy generation system. An introduction and analysis of the system, including its constituents, characteristics and excitation mechanism are presented first. Then, validation of the MAS solution demonstrates its feasibility in meeting all the requirements of the system. Five kinds of agents are proposed to present the Energy Management System. Each agent is built as a three layered architecture. A macro MAS is also presented in detail with a framework containing its overall optimisation function based on JADE (Java Agent Development). Discussion about the agents’ behaviours and a scenario case study on the MAS and its testing process are included in the paper. It indicates that the MAS is a suitable solution for the energy management of the distributed hybrid renewable energy generation system. [ABSTRACT FROM AUTHOR]

Abstract: Biodiesel is an alternative fuel for conventional diesel that is made from natural plant oils, animal fats, and waste cooking oils. This paper discusses the economics of producing biodiesel fuel from algae grown in open ponds. There is potential for large-scale production of biodiesel from algal farms on non-arable land; however, previous studies have failed to demonstrate an economically viable process that could be scalable to a commercialized industry. The problems include inconsistent and insufficient algal productivities, uncertain capital and operating costs, volatile market prices and unknown levels of government support. Although intensive work is being done on many technological issues, the economic studies and data are incomplete and out of date. This paper presents an updated financial analysis of the production and economic conditions that could have a profound effect on the success of this important alternative fuel production process. [Copyright &y& Elsevier]

The aim of the current work was to gather the largest possible sample of published data for vegetable oils properties, and conduct a statistical analysis in order to evaluate average values for all properties and for their fatty acid composition. A second objective was to investigate possible correlations between the properties and the degree of unsaturation. In order to achieve both tasks, the available literature on vegetable oils properties and their fatty acid composition was scanned from many well-established databases. In total, 695 papers were gathered that provided 550 different data series of oils properties and 536 of fatty acid composition, for 22 different oils. From the statistical analysis, collective results were derived for each property and quantified based on the specific oil. The effects of unsaturation were investigated too with separate best-fit linear curves provided for each interesting property with respect to the average number of double bonds. Unlike biodiesels, however, only a few (moderately) significant statistical correlations could be established between the vegetable oils properties and the degree of unsaturation, namely for cetane number, cloud and pour point and oxidation stability. [ABSTRACT FROM AUTHOR]

Abstract: Evaluation of reliability performance in every power system has to be done within a cost–benefit framework. This approach, however, is a very time consuming task, especially for systems that contain a large number of possible configurations, so simpler techniques referred to the calculation of reliability indices are used. In small autonomous power systems (SAPSs), such an evaluation uses mainly deterministic criteria. This approach, however, cannot be applied in SAPS that contain only renewable energy sources, due to the intermittent nature of the provided energy. In this paper, a complete reliability cost and worth analysis is implemented for these systems, combined with the calculation of some basic probabilistic indices, in order to discover their performance and propose the appropriate of them as a criterion of optimal system configuration. This paper proposes that normalized energy reliability indices as system minutes and energy index of unavailability can be used as adequate criteria of system''s optimal performance. This conclusion is validated through a large number of sensitivity analysis studies that are based on different maximum annual loads and different mix of load types. [Copyright &y& Elsevier]

Abstract: For decades, photovoltaic (PV) modules have been manufactured and tested under conditions that are not globally representative. With the emergence of renewable energy as a viable alternative to fossil fuel, a greater level of scrutiny is being targeted towards standards by which this renewable energy generation is being attended. Standard test conditions (STC) along with the established mid-latitude-based reference spectra are among the standards used to rate PV modules internationally. However, with the global impact that renewable energy technology is currently having and will continue to have in the future, such a new system that accounts for low-latitude regions of the world is imperative; and it has been proposed through this research paper. The model capitalizes on the gains of the current standards used, in order to account for the differences in the combination of spectral distribution, module temperature, solar irradiance and meteorological conditions that are representative of lower latitude regions. Equally important, the development of regional spectra is expected to increase the level of interest and investments in this technology, yielding an economy of scale reduction in the cost of solar PV systems in the region. This work centers on the need to develop a system of regional standardization using the Caribbean and Latin America as a test case. New reference spectra are proposed with the advantage of more relevant solar ratings for the region. The methodology employed in this research paper is also being proposed as a generic tool for other regions exploring regional standardization. [Copyright &y& Elsevier]

The present paper reports the microwave assisted intensification of biodiesel production from waste cooking oil using heterogeneous base catalyst - calcium diglyceroxide. Initially, experiments were carried out by varying various parameters such as reaction temperature, catalyst loading, and methanol to waste cooking oil (WCO) molar ratio using one factor at a time (OFAT) approach, to estimate the best condition. Response surface methodology (RSM) was applied to optimize the process variables, using the Box-Behnken model with three level and three factor. Under the optimized reaction conditions of methanol (MeOH) to WCO molar ratio of 7.46:1, catalyst loading of 1.03% (w/w of WCO) and temperature of 62 °C in the presence of microwave, a maximum biodiesel yield of 94.86% was obtained, whereas in the conventional heating method showed 42.59% yield for the similar reaction time of 15 min. Reusability of the catalyst was also tested, after the first run catalytic activity of calcium diglyceroxide was decreased for consecutive cycles. The transesterification of WCO followed pseudo first-order kinetics model. The activation energy and per-exponential factor were found to be 26.56 kJ mol − 1 and 1.65 × 10 3 min − 1 , respectively. The fuel properties of biodiesel matched with the American Society for Testing and Materials (ASTM-D6751) standards. [ABSTRACT FROM AUTHOR]

The important energy requirements for the desalination process impose especially in autonomous and decentralized plants supplied by Renewable Energy Sources (RES). In this paper, five alternative energy generation topologies of Reverse Osmosis desalination process are evaluated. The proposed topologies assessed in terms of economic, environmental, technological and societal indices are compared using multi-criteria analysis, namely the Analytic Hierarchy Process (AHP) and the Preference Ranking Organization Method for Enrichment of Evaluations (PROMETHEE). Ranking of topologies resulted in the selection of direct connection and hybrid configuration as optimum solutions. In case economic priorities prevail diesel generation should also be considered. [ABSTRACT FROM AUTHOR]

Abstract: The use of alternative fuels, as biodiesel and ethanol, for light duty CI engines to approach the target of ultra low NO x and PM emissions without fuel economy penalty has been widely investigated. Recently, it is growing the interest in the butanol as a viable alternative either single or blended with conventional based fuels both to cut the demand for fossil fuel and to reduce emissions of particulate matter without significantly increasing in NO x . In this paper, butanol effects on combustion process were investigated through conventional methods and optical diagnostics. First, blends of 80% diesel and 20% n-butanol (BU20) were used in a four cylinder, turbocharged, water cooled, DI diesel engine, equipped with a common rail injection system. Management of timing and injection pressure was carried out to achieve conditions in which the almost total amount of fuel was delivered before auto-ignition. BU20 allowed to attain almost smokeless emissions at lower injection pressure (100 MPa) than diesel fuel (120 MPa). Smokeless conditions were achieved with a slight increase in NO x emissions (around 20%) and a minor penalty for the specific fuel consumption. Afterward, the blends effects on the combustion process were studied in the combustion chamber of a single cylinder compression ignition engine equipped with the same common rail multi-jets injection system. Spray combustion and pollutant formation were investigated by UV–visible digital imaging and natural emission spectroscopy. UV–visible emission spectroscopy was used for the detection of the chemical markers of combustion process. Chemiluminescence signals, due to OH, HCO and CO2 emission bands were detected. OH emission was correlated to NO x measured at the exhaust. The soot spectral feature in the visible wavelength range was related to the engine out soot emissions. [Copyright &y& Elsevier]

Abstract: An experimental investigation of emissions characteristics of lower–higher molecular mass alcohol blended gasoline fuels is presented in this paper. The alcohol component of the blends consisted of methanol, ethanol, propanol, butanol and pentanol. Apparatuses used in the present study were a single cylinder spark ignition engine, a hydraulic dynamometer and an exhaust analyzer. The variables that were continuously measured include engine rotational speed (min−1), CO, CO2, HC and NO emissions. During variable load tests, the results indicate that CO and HC levels in the engine exhaust are reduced with the operation on alcohol gasoline blends. NO emissions with alcohol gasoline blends are higher than with gasoline. [Copyright &y& Elsevier]

Abstract: This paper considers biodiesel production from residues; tallow and used cooking oil (UCO). The tallow system is more complex involving two processes. The first process is rendering in which tallow (animal fat) and Meat and Bone Meal (MBM) are produced from the slaughter of cattle. MBM is assumed as a thermal energy source for cement manufacture and thus is not used for biodiesel production. The second process is biodiesel production from tallow. Three methodologies are employed to examine sustainability of the biodiesel. The no allocation approach assigns all the parasitic demands to the tallow; thus all energies required to make both MBM and tallow are associated with the tallow biodiesel. The resulting energy balance is negative. The substitution approach allocates the energy in MBM (used to produce cement) to tallow biodiesel. This results in the net energy being greater than the gross energy. The allocation by energy content method divides the parasitic demands of the rendering process between tallow and MBM by energy content. The parasitic demands of the biodiesel process are divided by energy content of the biodiesel, glycerol and K-fertiliser. For tallow biodiesel this yielded a net energy value of 38.6% of gross energy. The same method generated a net energy value of 67% for UCO biodiesel. More importantly the recommended method (allocation by energy content) generated a value of 54% greenhouse gas (GHG) emission savings for tallow and a value of 69% for UCO. Plants commencing after 2017, need to have a 60% GHG emission savings, to be considered sustainable. Thus a facility treating both feedstocks would need to treat a maximum of 60% tallow to be considered sustainable after 2017. [Copyright &y& Elsevier]

Abstract: This paper presents the pico-hydro development status in Lao PDR and introduces the Pump as Turbine (PAT) concept as an alternative for isolated communities (40–500 people). The intention is to provide a long-term reproducible system for communities where pico-hydro propeller turbines are insufficient and proper turbines are expensive. This approach presents a high quality and cost-effective solution for rural electrification which can be installed, commissioned, and maintained by local staff and villagers. Furthermore, a 2kWel PAT-scheme is proposed for a community in the Xiagnabouli province and considers power generation alternatives, sizing, asynchronous motor simulation, civil works, cost estimation, and social aspects. [Copyright &y& Elsevier]

Abstract: This paper presents the details of development of a biodiesel production test rig based on hydrodynamic cavitation followed by results of experimental investigation carried out on a four cylinder, direct injection water cooled diesel engine operating on diesel and biodiesel blend of Citrullus colocyntis (Thumba) oil. The experiment covers a wide range of engine rpm. Results show that biodiesel of Thumba oil produced through hydrodynamic cavitation technique can be used as an alternative fuel with better performance and lower emissions compared to diesel. The most significant conclusions are that (i) Biodiesel production through hydrodynamic cavitation technique seems to be a simple, efficient, time saving, eco-friendly and industrially viable process. (ii) 30% biodiesel blend of Thumba oil shows relatively higher brake power, brake thermal efficiency, reduced bsfc and smoke opacity with favourable p–θ diagram as compared to diesel. [Copyright &y& Elsevier]

Abstract: This paper presents a new framework to help assessing the success and its drivers of biomass energy projects. Empirical validation of the framework using data collected from operating grid-connected biomass energy plants in Thailand indicates that competencies of developer and project team members in designing biomass energy plants and conducting environment impact assessment (EIA) are significant factors for the success of the project development phase. In the construction phase, effective coordination, consultation and communication among the project team and the contractors emerge as the most significant success factors, while a competent management and O&M team is found critical to success during the operation phase. External factors such as the presence of supportive legislative, political and regulatory framework are found most instrumental for achieving overall project success. The framework demonstrates the dynamic linkage of project management success in successive lifecycle stages and phases, and thus can be used to evaluate and forecast the likelihood of success of biomass energy projects progressively over their lifecycle. [Copyright &y& Elsevier]

Abstract: Diesterol is a new specific term which denotes a mixture of fossil diesel fuel (D), vegetable oil methyl ester called biodiesel (B) and plant derived ethanol (E). In the context of the present paper, this term refers specifically to the combination of diesel fuel, bioethanol produced from potato waste, dehydrated in a vapor phase using 3A Zeolite, and sunflower methyl ester produced through transesterification. The mixture of DBE, i.e. diesterol, was patented under the Iranian patent No. 39407, dated 12-3-2007. The main purpose of this research work was to reduce engine exhaust NO x , CO, HC and smoke emissions due to application of biofuel and the increase of fuel oxygen content. It was needed to prepare suitable low cost and renewable additives. The diesterol properties such as pour point, viscosity, flash point, copper strip corrosion, ash content, sulfur content and cetane number were determined experimentally. The optimum ratio of bioethanol and biodiesel was found to be 40/60 considering fuel oxygen content, fuel price and mixture properties. Bioethanol was added to enhance the oxygenated component in the fuel, while the sunflower methyl ester was added to maintain the fuel stability at low temperatures. The parameters considered for investigation are the engine power, torque, specific fuel consumption and exhaust emissions for various mixture proportions. The experimental results showed that bioethanol plays an important role in determining the flash point of the blends. By adding 3% bioethanol to diesel and sunflower methyl ester, the flash point was reduced by 16°C. The viscosity of the blend was also reduced by increasing the amount of bioethanol. The sulfur content of bioethanol and sunflower methyl ester is very low compared to diesel fuel. The sulfur content of diesel is 500ppm whereas that of bioethanol and sunflower methyl ester is 0 and 15ppm, respectively. This lower sulfur content is another factor enhancing the use of fuel blends in diesel engines. The bioethanol and sunflower methyl ester combination has sulfur content less than 20ppm. The maximum power and torque using diesel fuel were 17.75 kW and 64.2Nm at 3600 and 2400rpm, respectively. Adding oxygenated compounds to the new blend seems to slightly reduce the engine power and torque and increased the average sfc for various speeds. The experimental measurement and observation of smoke concentration, NO x , CO and HC concentration indicated that both of these pollutants reduced by increasing the biofuel composition of diesterol throughout the engine operating range. [Copyright &y& Elsevier]

Abstract: The paper assesses the energy and environmental performance of two solutions designed to complement renewable energy (RE) technologies, in stand-alone power system (SAPS) configuration typical of minor Mediterranean islands, by converting the available RE surplus. The studied SAPS, based on the Ventotene island demographic, meteorological and load data, features high renewable energy penetration onto the load power demand, i.e. up to 55.25% share of peak power capacity. Transient models have been developed to simulate the storage process of winter renewable energy surplus and the time-dependent matching among SAPS electric demand and the stochastic renewable power contributions combined with energy surplus conversion systems. The study compares a hydrogen-based system and a desalinated water-production system, proposed as two effective alternatives for renewable energy seasonal buffering in an island context. The comparative analysis of the time-dependent system''s behaviour has been investigated with an hourly distribution over the period of one reference year, in terms of fuel consumption and hydrogen system energy storage or desalination capacity. The assessment is carried out by taking performance indicators, SAPS fuel savings, as well as stored and dump power data. The study demonstrates the suitability of both the models for the winter renewable energy buffer, in order to improve to the matching of peak energy and water demands. [Copyright &y& Elsevier]

Abstract: Energy policies may lead to important industrial outcomes. This paper investigates the impacts of energy policies on industry growth in renewable energy. Research tools employed include the commercialization process, value chain analysis, and empirical case studies. Different renewable energy technologies and geographical regions are considered covering over 50% of the world markets of the technology fields considered. Market deployment measures that enhance home markets of domestic industries will in most cases lead to growing industrial activities. Irrespective of the domestic market situation, pure investment or R&D support alone to already strong industries in related fields may be powerful to help with diversification into sustainable energy business. Several exogenous factors such as timing, size factors, geography, etc. will influence both the industrial and policy positioning in practice. The results indicate that there are increased industrial opportunities in renewable energy to be captured not only by large countries or through large public resources, but also smaller countries can gain success through clever policies and optimal managing of the commercialization process. [Copyright &y& Elsevier]

Abstract: Biofuels are of rapidly growing interest for reasons of energy security, diversity, and sustainability – as well as for greenhouse gas mitigation. In recent years, the U.S. has enacted regulations – and adopted aggressive goals – to encourage increased usage of biofuels. Individual States (especially California) have taken even stronger positions with respect to biofuels. Initial efforts have focused mainly on ethanol, produced via fermentation of sugars from grains (especially corn). Today''s R&D focus is on “2nd Generation Biofuels” that are produced from a variety of biomass feedstocks utilizing a wide range of conversion technologies. This paper summarizes policy and regulatory drivers for biofuels in the U.S., describes usage trends and projections, and highlights major R&D efforts to promote development and commercialization of 2nd Generation Biofuels. R&D is being conducted in many areas, including biomass resource assessment, development of new biomass feedstocks, improved conversion technologies, and integration of systems. Other important considerations include fuel quality and specifications, as well as requirements for blending, distribution, and storage. Considerable R&D, policy, and regulatory efforts are also focused on the energy and environmental consequences of biofuels. This includes not only direct emissions associated with vehicular uses, but also the fuels'' life-cycle impacts with respect to total energy usage, greenhouse gas emissions, and multi-media effects. Due to the wide diversity of biomass feedstocks, conversion technologies, and systems integration approaches, the life-cycle impacts of biofuels can vary widely. [Copyright &y& Elsevier]

Abstract: One of the attractions of developing bioenergy systems is the potential for job creation and economic development of rural economies. This paper seeks to quantify the expected employment impacts of individual bioenergy developments. The assessment includes agricultural labour growing energy crops for SRC and miscanthus options, transport and processing of the feedstock, staffing at the thermal conversion plant, employment within the equipment supply chain and the induced employment impact. Power only bioenergy systems are shown to typically create 1.27 man years of employment per GWh electricity produced, regardless of technology or scale of implementation. CHP systems can create more than 2 man years of employment per GWh electricity produced, although most of this enhanced economic impact can be attributed to the fact that a comparative analysis per unit of electricity produced ignores the heat output of the system. [Copyright &y& Elsevier]

The present study investigates the feasibility of synthesis of environmentally benign heterogeneous carbonaceous catalyst and biodiesel production from a single source i.e. Mesua ferrea Linn (MFL) seeds. The study primarily focuses on the optimisation of biodiesel synthesis process considering four parameters viz. reaction time, temperature, catalyst loading and methanol to oil ratio (M/O). The parametric influence on the free fatty acid (FFA) conversion has been studied to evaluate the most significant parameters. The contribution factor and analysis of variance results reveal that temperature is the most significant parameter influencing the FFA conversion followed by reaction time and catalyst content. The optimum conditions observed for maximum FFA conversion of 95.57% were: temperature 55 °C, time 2 h, catalyst content 10 wt% and M/O 6:1. The physico-chemical properties of the produced Mesua ferrea oil methyl ester (MFOME) were analysed following ASTM standard methods and found to be within limit; and compatible with the conventional diesel. Thus, the study suggests that the MFL seeds could be a promising source for the synthesis of an effective heterogeneous catalyst; and eco-friendly energy efficient sustainable fuel through the concept of green chemistry by converting waste into valuable commodity towards mitigation of increased energy demand. [ABSTRACT FROM AUTHOR]