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SUMMARY Previous studies by the authors have shown that energy savings in pulp and paper mills offer opportunities for increased electricity production on-site or wood fuel export. The energy export implies reductions in CO2 emissions off-site, where fossil fuel or fossil-fuel-based electricity is replaced. To assess this potential and the related profitability for a future situation, four energy market scenarios were used. For a typical Scandinavian mill, the potential for CO2-emission reductions was 15-140 kton year−1 depending on the scenario and the form of energy export. Extrapolated to all relevant mills in Sweden, the potential was 0.4-3.1 Mton year−1, which is in the order of percent of the Swedish CO2 emissions. Wood fuel export implies larger reduction in CO2 emissions in most scenarios. In contrast, electricity export showed better economy in most of the cases studied; with annual earnings of 5-6 M€, this is an economically robust option. In the market pulp mill investigated, the wood fuel export was in the form of lignin. Lignin could possibly be valued as oil, regarding both price and potential for CO2-emission reduction, making lignin separation an option with good profitability and large reductions of CO2 emissions. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper performs a technoeconomic analysis of the wind power potential and evaluates the cost of wind power generation in Evodoula, comparing two methods, the conventional method and the uncertainty method based on a comparative spatiotemporal approach using the geographic information system (GIS) software tool. This study is based on satellite wind data measured at 10 m above ground level (AGL) over a 40-year period (1980-2019), by the meteorological service NASA (National Aeronautics and Space Administration)/Goddard Space Flight Center (GSFC). The main objectives are to obtain an appropriate design for a proven optimal location and to assess the viability of wind power at Evodoula. For this type of study, there is little literature available. The optimization of an onshore wind farm and deployment in the wind energy development interest area (ZIDEE) is carried out to obtain a minimum and parsimonious discounted cost production unitary (CPU) of the electricity produced. The results showed that in Okok, a location with a large energy deficit, an onshore wind farm with an electricity generation capacity of 12.5 MW with 5 NORDEX N100-2.5MW wind turbines would have a total energy production (TEP) of about 64.0254825 TWh and a selling price of electricity that would be 0.0034 CAD$/kWh, which is very low compared to the utility price (about 98% cheaper). The total cost of the wind farm would be about $11 million, with a net present cost of about $218 million. The annual profit generated by the wind farm would be over $6 billion. The return on investment (ROI) of the project is estimated at 2880.882%. The constructed onshore wind farm would avoid CO2 emission at over 11 Mt CO 2 , eq /year as the energy generated is from the atmosphere. The wind farm would realize an average annual cash flow estimated at nearly $30 million after 20 years of operation. These savings would allow the installation of CO2 capture systems in conventional power plants. In addition, the analysis of uncertainties and risks was identified and quantified to estimate the confidence levels of the project development results. The risks have been assessed, and we recommend that the total uncertainty of the project is around 15%. The energy values in P 75 and P 90 are 10.08% and 19.22%, respectively, lower than the energy value in P 50 of 11.60 GWh/An. Finally, the main policy recommendations for an inclusive design process are highlighted. The contribution of this study is to assist policy makers in making appropriate decisions in the development and implementation of energy and environmental policy in Cameroon and in many continental areas. [ABSTRACT FROM AUTHOR]

Summary: Many electricity consumers around the world are billed electric peak load charges. In the United States, these demand charges can contribute up to 70% of a consumer's electricity bill. Research has shown that the financial impact of these charges to the consumers can be reduced by acting on the intelligence provided by peak electric load day (PELD) forecasts. Unfortunately, published research detailing PELDs forecasting methodologies for facilities adopting behind the meter renewable electricity generation (BTMREG) is non‐existent. This paper contributes: (a) a PELD forecasting methodology applicable to consumers with BTMREG. A case study demonstrates the methodology's ability to achieve 93% of the potential savings in kW, translating to demand charge reductions of approximately US$ 142 129 per year. (b) The first side‐by‐side performance comparisons of electric load and PELD forecasting models for scenarios with and without BTMREG. (c) The first PELD forecasting model savings comparison for scenarios with and without BTMREG. Experimental results suggest that counterintuitively, BTMREG adoption can translate into higher peak load savings for electricity consumers. [ABSTRACT FROM AUTHOR]

This paper estimates the maximum integration level of residential rooftop solar photovoltaic (PV) capacity within the power network of the Duke Energy Progress (DEP) and Duke Energy Carolinas (DEC) under two scenarios embodying different assumptions about the flexibility of nuclear power plant (NPP) operations. A mixed-integer optimization model was constructed and simulated to find out the maximum solar penetration level under each scenario and to calculate the expected total system's electricity generation costs, energy mix, atmospheric emission reductions, and emission abatement costs. Analysis reveals that improving NPP operation maneuverability would increase the maximum solar PV penetration level in the DEP and DEC power networks by 39%, from 8.9% to 12.4% of the total system's electricity generation. Consequently, it would further improve the electricity generations' unit costs and CO2 emission reductions by 3% and 8% points, respectively. On the other hand, increasing the solar PV penetration limit under high flexible NPP operation scenario leads to increase in the CO2 emission abatement costs by 8% points. The results of the study indicate that the flexibility of existing power system resources may present a barrier for a large uptake of solar energy. [ABSTRACT FROM AUTHOR]

Summary: The uncertainties related to renewable energy resources (RERs) and energy markets have a direct impact on the scheduling of hybrid microgrids and stand as a challenge in renewable‐based systems. Due to this, many mathematical methods are employed for modeling uncertainties, but applying a suitable approach is important for reaching accurate results. This paper presents the chance‐constrained programming technique to model the fluctuations in renewable outputs and electricity market prices to effectively deliberate the probabilistic nature of them. In this respect, the transactive energy concept is used to provide the energy sharing possibility for hybrid microgrids with a high portion of renewables for clean electricity generation. The interaction between the electrical and gas network as a result of using the gas‐fired devices in each microgrid, is also included in this study. To test the effectiveness of the suggested framework, the IEEE‐10 bus case study with five commercial hybrid microgrids is selected and the scheduling of microgrids is carried out in the interconnected electricity and gas networks. The different impacts of the proposed method are analyzed by considering two cases: optimal scheduling of hybrid microgrids without uncertainty modeling (Case I) and with it (Case II). In Case I and II, numerical results indicated $22 378.067 expected operation cost for Case II in comparison with $26 014.359 for Case I, which proves the effectiveness of the proposed model in probabilistic modeling of the system as well as achieving the economic benefits for hybrid microgrids. Highlights: Optimal chance‐constrained DA scheduling of hybrid microgrids is effectively conducted.The CCP method is used for probabilistic evaluation of the problem in the presence of RERs.Transactive energy technology is employed for managing energy trading in the system.LHS and FFS methods are applied for scenario generation and reduction, respectively.The interactions between electricity and gas networks are effectively modeled. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a comparative study of novel energy integrations between Multiple‐Effect Desalination (MED) and Organic Rankine Cycle (ORC) systems for the simultaneous production of desalinated water and electric power. Two new MED/ORC configurations are proposed, where part of the sensible and/or latent heat of condensation of the ORC is used to potentiate the generation of steam in the last effect of the MED, taking advantage of the temperature levels present in the MED. A simulator of the proposals was developed and validated with experimental results reported in the literature. These configurations are compared energetically with the MED and ORC systems working individually and against another previously proposed configuration, also considering the impact of the integrations on the heat transfer area required by the systems. The results show a decrease in the thermal energy requirements for the activation of the MED system with the new integrations. The energy requirements of the MED are reduced by 28% when integrated into the first effect with the ORC evaporator. The utilization of the sensible heat of condensation of the ORC in configuration 3 did not present a considerable energy decrease compared to configuration 2, due to the limited sensible heat available for its recovery, of approximately 22 kW. The usage of the latent heat of condensation of the ORC in configuration 4 implies that increasing the condensation temperature and pressure of the ORC, decreases its efficiency by 1.8% and increasing the energy required by 221 kW provides the two services simultaneously. [ABSTRACT FROM AUTHOR]

Summary: Electric‐driven heat pumps are one of the most encouraging systems that could support the raising of renewables contribution in civil sector energy consumption, especially with reference to the Countries with a high contribution of renewable energy sources in electricity generation mix. However, the evaluation of the effective energy and environmental performance of an electric heat pump meeting the space heating and cooling requests of a building has to consider several factors that affect the results. Among them great attention should be given to the variability of weather conditions in which the system operates, the changeability of the efficiency and environmental indicators of power grid. The analysis becomes more complex if the variation of these parameters is considered in terms of time and geographic location but it leads to the actual evaluation of the energy conversion system performance that is neglected by European Regulations. This paper presents an energy and environmental analysis of an electric‐driven air‐source heat pump providing the space heating and cooling needs of the same building located in two different geographical locations by means of a dynamic simulation performed in TRNSYS 17. The analysis is carried out considering the average and time‐dependent values of the carbon dioxide emission factors for electricity and the power grid efficiency indicators evaluated by means of the real electricity generation data. In addition, the paper proposes the evaluation of the average and hourly energy and environmental parameters referred only to the electricity market zones in which the buildings are located. These indices are considered in the analysis too. The results have highlighted that the assessment based on average and high‐resolution parameters, as well the evaluation based on indicators referred to electricity market zones only, could return very different outcomes leading to a significant overestimation or underestimation of the energy and environmental performance of the system based on the electric‐driven heat pump. Finally, a further analysis has been carried out to determine how the results can vary considering the average value of the electric efficiency indicator suggested by Italian Regulations and that of other European Countries. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a techno‐economic analysis of photovoltaic mini‐grid systems (PMs), using a group of remote houses in 3 locations in Nigeria, as case studies. It uses a worst‐case users' load demand approach for the design and analysis of the proposed energy system, according to international technical standards. It presents detailed capacity, yield and losses, battery state of charge (SoC), reliability, users' load demand increase (Ldi), and life cycle economic analyses by using the Hybrid Optimisation for Electric Renewables (HOMER) simulation tool. The effect of 25% Ldi is also considered in the paper. The study can be used to develop a practical energy model to address the poor energy situation in those locations when they are implemented. Results indicate that PMs of 68, 76, and 61 kW can meet the users' demand of ~63 500 kWh/year with an availability of 99.2% for the locations, respectively. By including a 30‐kVA diesel generator to the PMs' model, an availability of 100% was obtained, demonstrating that the issue of loss of energy supply for several days in the year due to users' Ldi and the cloudy days is being addressed. The results further show that although the hybrid energy systems have relatively higher initial capital, total life cycle and replacement costs, and the cost of energy, they achieve a higher reliability compared with the proposed PMs. The research can be useful for planning solar PV infrastructure for remote locations around the world. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a comparative life cycle assessment of two types of H2 carriers, methanol and ammonia, using GaBi 10 software. Two types of H2 carriers that is, methanol and ammonia are compared from coal, natural gas and renewables, respectively. The full supply chain is considered in the carbon footprint evaluation, which contains production, storage, transportation, and utilization phase. The energy analysis results show that H2 carrier produced from natural gas has higher energy efficiency than that from renewables, which can be attributed to the high energy consumption during H2 generation in the latter. Carbon footprint evaluation indicates that solar PV‐based ammonia production route has the lowest GWP in all scenarios, with a value of 43.9 g of CO2‐Equation MJ−1 of ammonia. In addition, electricity has been found as the key factor affecting GHG emissions in the routes of fuels produced from renewable H2 through sensitivity analysis. By optimizing electricity generation and expanding the carbon capture scale of power plant, the GHG emissions level of CCU‐based methanol production route and solar PV‐based ammonia production route can be further reduced. [ABSTRACT FROM AUTHOR]

Summary: In the existent paper, the performance of thermal storage hybrid buildings exploiting the latent heat of phase change materials (PCMs) for thermal refrigeration and heating of the contemporary period has been investigated. The conventional buildings consume a large amount of electricity, primarily for the heating and cooling applications. Electricity generation primarily relies on coal‐based thermal power plants. The emissions from these establishments pose a serious threat to the environment. Moreover, conventional heating/cooling units rely on exorbitant energy cost. The usage of any kind of thermal storage system is an efficacious way of stockpiling thermal energy and utilizing it when needed. This paper gives a comprehensive overview of the available thermal storage units incorporating PCMs. The various segments of the buildings, viz, ceiling, window, wall, and floor have been analyzed in details. The results are quite promising in terms of load reduction and overall energy saving. Indoor surface temperature reduction of up to 7oC has been achieved. The energy saving of up to 40% can be realized by employing PCM. A comprehensive list of the PCMs is also tried to build up for end users according to their temperature requirement. [ABSTRACT FROM AUTHOR]

Summary: In addition to directly burning in firepower plants, coal can be alternatively gasified into gaseous carbon monoxide and then fed into solid oxide fuel cells for efficient power generation. Carbon monoxide solid oxide fuel cells (CO‐SOFCs) not only avoid the drawbacks of expensive hydrogen fuel but also facilitate carbon dioxide's separation and enrichment. In this paper, an integrated system is first presented to efficiently recycle the waste heat released from CO‐SOFCs via alkali metal thermoelectric converters (AMTECs) for additional electricity generation. Key performance indicators such as power density and energy efficiency are mathematically expressed by including the heat‐transfer losses between heat sources and AMTEC. The maximum power density of the integrated system gains 18% improvement compared with that of the sole CO‐SOFC. The maximum efficiency can reach 60.84%. The optimum ranges of the current density, efficiency, and power density for the whole integrated system are determined. Furthermore, the influences of the fuel cell temperature on the optimum ranges are also studied. The correlations between the critical parameters and the maximum power density and efficiency of the system are revealed. The maximum power density and efficiency as well as the corresponding parameters are calculated numerically. The findings show that waste heat can be recycled efficiently by employing AMTECs. Novelty Statement: A numerical model of the CO‐SOFC/AMTEC integrated system is established.The maximum efficiency of the hybrid system can reach 60.84%.The optimum ranges of key parameters are determined and discussed. [ABSTRACT FROM AUTHOR]

This paper mainly studied the solid oxide fuel cell (SOFC)-micro gas turbine (MGT) hybrid power system. The key parameters that greatly influence the overall system performance have been studied and optimized. The thermodynamic potential of improving the hybrid system performance by integrating SOFC with the advanced thermal cycle system is analyzed. The optimization rules of main parameters of SOFC-MGT hybrid power system with the turbine inlet temperature (TIT) of MGT as a constraint condition are revealed. The research results show that TIT is a key parameter that limits the electrical efficiency of hybrid power system. With the increase of the cell number, both the power generation efficiency of the hybrid cycle power system and TIT increase. Regarding the hybrid system with the fixed cell number, in order to get a higher electrical efficiency, the operating temperature of SOFC should be enhanced as far as possible. However, the higher operating temperature will result in the higher TIT. Increasing of fuel utilization factor is an effective measure to improve the performance of hybrid system. At the same time, TIT increases slightly. Both the electrical efficiency of hybrid power system and TIT reduce with the increase of the ratio of steam to carbon. The achievements obtained from this paper will provide valuable information for further study on SOFC-MGT hybrid power system with high efficiency. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The method of determination of the control variables for a system controller, which controls the electric power output of a solid-polymer-membrane (PEM) fuel cell system during electric power load fluctuations, was considered. The operation was clarified for the response characteristics of electric power generation for setting the control variables of proportional action and integral action considered to be the optimal for the system controller. The power load pattern of an individual house consists of loads usually moved up and down rapidly for a short time. Until now, there have been no examples showing the characteristics of the power generation efficiency of a system that follows a load pattern that moves up and down rapidly. Therefore, this paper investigates the relation of the control variables and power generation efficiency when adding change that simulates the load of a house to PEM fuel cell cogeneration. As a result, it was shown that an operation, minimally influenced by load fluctuations, can be performed by changing the control variables using the value of the electric power load of a system. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Conventional energy systems in both developed and developing economies are currently run by fossil‐fueled power plants. Many of them are ageing and are now being considered for the replacement to reduce the carbon intensity in electricity generation. One of the main routes to achieve this goal is by scaling‐up the deployment of the renewable energy system (RES). However, the increasing share of variable RES tends to affect the electrical grid operation. Hence, the need for reliable and flexible energy sources has emerged to cope with the variability in electricity and energy markets. Small modular reactors (SMRs) are emerging as alternatives to baseload fossil fuel systems and retiring large nuclear plants, primarily due to their small capacity and less‐capital intensive characteristics. The intermittency of power generation in the grid with a higher share of RES can be coped with in synergetic and effective way by adopting SMRs that form a nuclear‐renewable synergy in fulfilling the electricity demand. Furthermore, SMRs are designed to operate in load‐following mode adjusting the power output as demand of electricity fluctuates. SMRs feature modularity intended to enable enhanced constructability and phased‐deployment, adapting to the increased share of renewable energy in a distributed energy system, as energy demand increases. This paper will highlight the main outcomes of miscellaneous recent studies on the integrated energy systems carried out by international experts under the aegis of the International Atomic Energy Agency. The final publication of the study discusses the potential synergy of SMRs with RES for electric power production, as well as for other clean‐energy applications including seawater desalination, district heating, and hydrogen production. [ABSTRACT FROM AUTHOR]

High-temperature steam electrolysis (HTSE) consists of the splitting of steam into hydrogen and oxygen at high temperature in solid oxide electrolyzers. Performing the electrolysis process at high temperatures offers the advantage of achieving higher efficiencies as compared to the conventional water electrolysis. Furthermore, this allows the direct use of process heat to generate steam. This paper is related to the FCH JU (Fuel Cells and Hydrogen Joint Undertaking) project ADEL (ADvanced ELectrolyser For hydrogen Production with Renewable Energy Sources), which investigates different carbon-free energy sources to be coupled to the HTSE process. Renewable energy sources are able to provide the high-temperature steam electrolysis (HTSE) process with heat and power. This paper investigates the capability of Concentrating Solar Power (CSP) technologies to provide the HTSE process with the necessary energy demand. The layout of the plant is shown in the following figure. The design of commercial-scale high-temperature steam electrolysis has been carried out. The HTSE plant is coupled to an air cooled solar tower. The configuration and the operating parameters of the solar tower are based on those of the solar tower of Jülich (Germany), which is operated by DLR. This paper presents the results of process analysis performed to evaluate the hydrogen production from a HTSE plant coupled to an 80MWth air solar tower. Additionally, the dynamic behavior of the system during energy fluctuations has been analyzed. The receiver-to-hydrogen efficiency (based on the Higher Heating Value of hydrogen) is 26% at a hydrogen production rate of 680 kg/h in steady-state operation. The overall solar-to-hydrogen efficiency is calculated to be at 18%. Moreover, the analysis under transient conditions shows that a steady-state operation of the plant is only possible for 8 h. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY This paper describes the problem of short-term wind power production forecasting based on meteorological information. Aggregated wind power forecasts are produced for multiple wind farms using a hybrid intelligent algorithm that uses a data filtering technique based on wavelet transform (WT) and a soft computing model (SCM) based on neural network (NN), which is optimized by using particle swarm optimization (PSO) algorithm. To demonstrate the effectiveness of the proposed hybrid intelligent WT + NNPSO model, which takes into account the interactions of wind power, wind speed, wind direction, and temperature in the forecast process, the real data of wind farms located in the southern Alberta, Canada, are used to train and test the proposed model. The test results produced by the proposed hybrid WT + NNPSO model are compared with other SCMs as well as the benchmark persistence method. Simulation results demonstrate that the proposed technique is capable of performing effectively with the variability and intermittency of wind power generation series in order to produce accurate wind power forecasts. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Growth in global energy demand, with major fossil fuel consumption, has induced detrimental environmental and social impacts. Therefore, in recent years, technologies focused on renewable energy utilization, including biomass energy, have evolved to meet the energy requirements. Bioenergy‐based power generation systems are among the best‐unutilized configurations to diminish reliance on fossil fuels. However, it is difficult to select a biomass‐based configuration for economical, sustainable, and reliable power generation. Understanding different possible configurations of biomass‐based energy systems, design parameters, system research gaps, and integration challenges in biomass‐based energy systems are important for further development and propagation. This paper presents a critical review of biomass‐based different hybrid configurations with solar, wind, fuel cell, micro‐hydro, geothermal, and diesel generator, and various designing parameters, challenges, and gaps with future scope. To restrict the scope of the review, only the gasification and anaerobic digestion related biomass electricity generation systems are considered. The analysis indicates that the biomass‐based hybrid energy systems can provide an eco‐friendly and cost‐effective solution, especially for off‐grid rural electrification. The solar radiation, load demand, fuel price, capacity shortage, interest rate, wind speed, biomass quantity, and electricity rate are among the most critical designing parameters in biomass‐based energy systems. The study provides valuable information to designers, researchers, and policy makers on the latest design constraints and relevant policies relating to biomass‐based hybrid energy systems. [ABSTRACT FROM AUTHOR]

Summary: The world has witnessed a substantial upsurge in energy demand in the recent decades, which has concurrently led to increased environmental contamination due to the use of carbon‐based fuels to meet this demand. The increased pollution levels across the globe combined with the rapid depletion of these carbon‐based non‐renewable sources of energy has forced nations to adopt cleaner sources such as solar energy, wind energy, biomass etc. for meeting energy requirements. Utilities and power transmission companies, in several countries, have begun installation and operation of large‐scale solar energy projects in order to augment the present electricity generation capacity. India has a tremendous potential for solar energy as 58% of the total land area receives an average solar insolation above 5 kWh/m2/day, annually. However, PV installations require proper economic formulation and technical modelling of PV plants. The study presented in this paper investigates the feasibility of installing a 1 MW grid‐connected PV system in the arid climatic conditions of India. Four different regions of the Thar Desert: Barmer, Jodhpur, Jaisalmer, and Kalan Ghat have been considered for the study. A comparative study has been laid out based on energy yields, losses, and degradation of various module technologies namely mono‐Si, poly‐Si, CdTe, and CIS. The performance of the PV systems has been evaluated both in the fixed‐tilt and variable‐tilt configurations. Simulation results show that the daily yield in winter months ranges between 5.8 and 6.9 MWh/day whereas, during summer, it ranges between 5 and 7.1 MWh/day. The study suggests that CIS module is expected to produce highest annual energy yield of 2471 MWh with a PR of 86.1%, in the variable‐tilt configuration for the Jaisalmer region. Annual energy loss due to temperature is expected to be highest for mono‐Si technology (14.4%) in the variable‐tilt configuration and lowest for CIS technology (9.4%) in the fixed‐tilt configuation. Moreover, mismatch losses for all the four technologies lie in the range of 0.1‐1.1%. [ABSTRACT FROM AUTHOR]

Summary: To achieve a national energy access target of 90% urban and 51% rural by 2035, combat climate change, and diversify the energy sector in the country, the Zambian government is planning to integrate other renewable energy resources (RESs) such as wind, solar, biomass, and geothermal into the existing hydro generation–based power system. However, to achieve such targets, it is essential for the government to identify suitable combination of the RESs (electricity generation fuel mix) that can provide the greatest sustainability benefit to the country. In this paper, a multicriteria decision‐making framework based on analytic hierarchy process and system dynamics techniques is proposed to evaluate and identify the best electricity generation fuel mix for Zambia. The renewable energy generation technologies considered include wind, solar photovoltaic, biomass, and hydropower. The criteria used are categorized as technical, economic, environmental, social, and political. The proposed approach was applied to rank the electricity generation fuel mix based on nine sustainability aspects: land use, CO2 emissions, job creation, policy promotion affordability, subsidy cost, air pollution reduction, RES electricity production, RES cumulative capacity, and RES initial capital cost. The results indicate that based on availability of RESs and sustainability aspects, in overall, the best future electricity generation mix option for Zambia is scenario with higher hydropower (40%) penetration, wind (30%), solar (20%), and lower biomass (10%) penetration in the overall electricity generation fuel mix, which is mainly due to environmental issues and availability of primary energy resources. The results further indicate that solar ranks first in most of the scenarios even after the penetration weights of RES are adjusted in the sensitivity analysis. The wind was ranked second in most of the scenarios followed by hydropower and last was biomass. These developed electricity generation fuel mix pathways would enable the country meeting the future electricity generation needs target at minimized environmental and social impacts by 2035. Therefore, this study is essential to assist in policy and decision making including planning at strategic level for sustainable energy diversification. [ABSTRACT FROM AUTHOR]

SUMMARY This paper compares different energy-related investment options that can be implemented in a kraft pulp mill with a potential steam surplus. The options investigated include lignin extraction, electricity production, capturing of CO2 and black liquor gasification with production of electricity or biofuels, here DME. The investment options are compared with respect to annual net profit and global CO2 emissions for different future energy market scenarios. A further analysis of how different parameters such as policy instruments and investment costs affect the different technologies also is included. The results show that, generally, for reasonable levels of biofuel support, the best economic performance among the studied technologies is achieved by extraction of lignin valued as oil. However, if the level of support for biofuels is high, black liquor gasification with DME production generally has the best economic performance among the studied options. All the investment options investigated decrease global CO2 emissions significantly. Capturing and storing CO2 from the recovery boiler flue gases result in the highest CO2 emissions reduction and also is an economically attractive option in scenarios with a high CO2 emissions charge. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Solar photovoltaic system (SPV) has gained tremendous popularity among researchers as well as in industrialists. Although SPV is a transparent way of electricity generation; still, it suffers from lower quantum efficiency. During the conversion process, solar insolation received by the SPV array turns the system intensely heated at the back side of the modules giving rise to high temperature. This heat is further utilized by the process of thermoelectric effect for electricity generation by thermoelectric generators (TEGs). The combined photoelectric‐thermoelectric effect generates a significant amount of power for the system. This paper portrays on implementation of the aforementioned SPV‐TEG system in hybrid nonconventional distribution generator (h‐NDG) in order to retrieve enough power from SPV array giving rise to higher active power delivery to the system and lower the reactive power absorbance by the system. The comparative analysis is done under two subsystems such as solar PV‐TEG‐wind energy system (WES) over solar PV‐WES and solar PV‐TEG‐fuel cell technology (FCT) over SPV‐FCT. Several constraints like active power, reactive power, and solar power are studied for every subsystem under healthy and faulty conditions. The entire system is modeled, studied, and validated in the MATLAB‐Simulink environment. [ABSTRACT FROM AUTHOR]

Summary: Huge amount of energies is consumed by the air conditioning (A/C) to maintain the required temperature and humidity inside spaces/applications of high humidly. An innovative A/C system that recovers the condenser heat in process air reheating and other useful thermal utilization is presented and investigated in this paper. For high coefficient of performance (COP) of the AC and more energy‐efficient system, the cold exhaust air rejected by the air condition system is also utilized to cool the condenser of the AC system. Huge amount of the water condensate from the system is also utilized as freshwater production. Performance of the proposed system is analytically investigated for different operating conditions and system capacities. Mathematical model of the systems is developed and solved numerically using Engineering Equation Solver (EES) software. Results show that the proposed system enhances the COP and decreases the electric power consumption. The saving in electric power consumption, COP, and the freshwater production rate of the system increases with decreasing room‐sensible heat factor, fresh air ratio, and outdoor air temperature and humidity. Moreover, the COP of the proposed system is 90% higher than COP of the basis system, and the savings in the running cost of the system increase by 4.5 times with decreasing the room‐sensible heat factor (RSHF) from 0.6 to 0.2. In addition, the highest COP attained by the proposed system is 2.72, and the corresponding freshwater production rate is 373.8 kg/h. [ABSTRACT FROM AUTHOR]

Summary: In the context of China's "Internet Plus" era, the application of big data and energy storage technology etc. plays an important role in controlling the renewables of randomness and intermittence during the generation. This paper focuses on the development of China's Energy Storage Industry, summarizes the industrial situation and policy environment, analyses China's Energy Storage Industry by the PEST‐SWOT framework, and discusses the development trends and three cases under the "Internet Plus" initiative. At last, several recommendations are offered from energy storage system, development solutions, market design and international cooperation, aiming to cope with the issues concerning the development of China's Energy Storage Industry and future challenges. It is expected that such recommendations can be a boost to China's energy storage industry in the future. Current situation of China's Energy Storage Industry is investigated.Policy environment is presented and analyzed.The PEST‐SWOT framework of China's Energy Storage Industry is analyzed.The development trends and three cases of China's Energy Storage Industry under the "Internet Plus" initiative are discussed.The suggestion on promoting the development of China's Energy Storage Industry is proposed from energy storage system, development solutions, market design, and international cooperation. [ABSTRACT FROM AUTHOR]

Summary: Adsorption cooling technology is an effective method to use low‐temperature heat sources, such as solar energy, waste heat from industry, etc. However, there exists one bottleneck in the adsorption system application, because of its low energy usage efficiency. In this paper, one novel integrated cycle is designed, investigated, and tested. It includes adsorption cooling cycle, ammonia expanding power generation, and organic Rankine cycle. By the performance comparison of 16 different organics, R600 is the most suitable choice for organic Rankine cycle in this system, due to its highest potential exergy and proper working pressure. The system total exergy efficiency can be improved significantly by the two parts of power generation. The results show that when the heating source, cooling water temperature, and evaporation temperature are approximately 120.1°C, 29.6°C, and −5.3°C, the specific cooling power, coefficient of performance, and total exergy efficiency can arrive at 351.4 W/kg, 0.17, and 0.34, respectively. R600 is the most suitable choice for ORC in this system. The system total exergy efficiency can be improved significantly by the two parts of power generation. SCP, COP and total exergy efficiency can arrive at 351.4 W/kg, 0.17 and 0.34. [ABSTRACT FROM AUTHOR]

SUMMARY The objective of this paper is to study the performance of a combined heat and power (CHP) system that uses two power generation units (PGU). In addition, the effect of thermal energy storage is evaluated for the proposed dual-PGU CHP configuration (D-CHP). Two scenarios are evaluated in this paper. In the first scenario, one PGU operates at base-loading condition, while the second PGU operates following the electric load. In the second scenario, one PGU operates at base-loading condition, while the second PGU operates following the thermal load. The D-CHP system is modeled for the same building in four different locations to account for variation of the electric and thermal loads due to weather data. The D-CHP system results are compared with the reference building by using conventional technology to determine the benefits of this proposed system in terms of operational cost and carbon dioxide emissions. The D-CHP system results, with and without thermal storage, are also compared with that of single-PGU CHP systems operating following the electric load (FEL), following the thermal load (FTL), and base-loaded (BL). Results indicate that the D-CHP system operating either FEL or FTL in general provides better results than a single-PGU CHP system operating FEL, FTL, or BL. The addition of thermal storage enhances the potential benefits from D-CHP system operation in terms of operational cost savings and emissions savings. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Electricity demand response is considered an effective approach to balance the electricity demand and supply with existing infrastructure of generation, transmission, and distribution. A majority of existing literature on the electricity demand response has mainly centered on the commercial and residential building sectors while the application for the industrial sector is largely neglected. This paper presents a methodology for the application of a typical demand response program, Critical Peak Pricing (CPP) program, for the manufacturing enterprises. The configuration of the reservation capacity (in kilowatt, kW) in the CPP program, which plays a critical role in the cost of the final bill charge, will be identified by optimal production scheduling for the typical manufacturing systems with multiple machines and buffers. Mixed Integer Nonlinear Programming formulation is used to establish the mathematical model with the objective to minimize the electricity bill cost as well as the potential penalty cost due to the non-fulfillment of the target production. An approximate technique is introduced to find a near optimal solution, and a numerical case study is used to illustrate the effectiveness of the proposed method. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: In today's world striving for efficiency in every sector, especially power generation and distribution, smart grids emerge as the solution for efficiently meeting the increasing demand. They adjust themselves to optimally deliver energy at the lowest cost and highest quality possible. The grid successfully makes use of renewable energy resources, electric vehicles, and smart pricing techniques in its attempt to achieve energy efficiency. It also promotes a greener environment by striving to reduce greenhouse gas emissions. Information communication technology (ICT) helps the grid in collecting consumption data from the consumers and in sharing tariff information. ICT also helps to gather information about the status of the grid with regard to aspects like power quality, faults etc. The purpose of this paper is to review recent literature with a view to comprehensively present the technologies employed in the smart grid for achieving energy efficiency and the challenges involved therein. [ABSTRACT FROM AUTHOR]

In this paper, novel approaches for wind speed data generation using Mycielski algorithm are developed and presented. To show the accuracy of developed approaches, we used three-year collected wind speed data belonging to deliberately se-lected two different regions of Turkey (Izmir and Kayseri) to generate artificial wind speed data. The data belonging to the first two years are used for training, whereas the remaining one-year data are used for testing and accuracy comparison purposes. The concept of distinct synthetic data production with correlation-wise and distribution-wise similar statistical properties constitutes the main idea of the proposed methods for a successful artificial wind speed generation. Generated data are compared with test data for both regions in the sense of basic statistics, Weibull distribution parameters, transition probabilities, spectral densities, and autocorrelation functions; and are also compared with the data generated by the clas-sical first-order Markov chains method. Results indicate that the accuracy and realistic behavior of the proposed method is superior to the classical method in the literature. Comparisons and results are discussed in detail. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new comprehensive techno-economic analysis method for power generation systems with CO2 capture is proposed in this paper. The correlative relationship between the efficiency penalty, investment increment, and CO2 avoidance cost is established. Through theoretical derivation, typical system analysis, and variation trends investigation, the mutual influence between technical and economic factors and their impacts on the CO2 avoidance cost are studied. At the same time, the important role that system integration plays in CO2 avoidance is investigated based on the analysis of a novel partial gasification CO2 recovery system. The results reveal that for the power generation systems with CO2 capture, the efficiency penalty not only affects the costs on fuel, but the incremental investment cost for CO2 capture (U.S.$ kW-1) as well. Consequently, it will have a decisive impact on the CO2 avoidance cost. Therefore, the added attention should be paid to improve the technical performance in order to reduce the efficiency penalty in energy system with CO2 capture and storage. Additionally, the system integration may not only decrease the efficiency penalty, but also simplify the system structure and keep the investment increment at a low level, and thereby it reduces the CO2 avoidance cost significantly. For example, for the novel partial gasification CO2 recovery system, owing to system integration, its efficiency can reach 42.2%, with 70% of CO2 capture, and its investment cost is only 87$ kW-1 higher than that of the reference IGCC system, thereby the CO2 avoidance cost is only 6.23$ t-1 CO2. The obtained results provide a comprehensive technical–economical analysis method for energy systems with CO2 capture useful for reducing the avoidance costs. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A Stirling engine (SEG) using woody biomass is a power generation system that can reduce greenhouse gas discharge. However, improvement of generation efficiency and development of a product are required strongly. In this paper, the energy flow is investigated in experimenting in Test SEG. These results are installed into the energy demand pattern of a cold region houses with much heat demand, and the amount of fuel consumption, power generation efficiency, and a greenhouse gas amount of emission are investigated. Operations of the proposed system are SEG base-load operation and SEG power-load-following operation. Moreover, when there is less exhaust heat of the SEG than a heat demand amount, electric heat pump is operated. From analysis results, the energy cost, the greenhouse gas emission characteristic, the auxiliary heat source, and the operation plan of a heat storage tank due to the conventional method and the proposed system are described. It is thought that greenhouse gas and the energy cost of the SEG cogeneration made to follow power load are advantageous compared with the SEG base-load operation. However, it turned out that improvement in the speed of the load response characteristic of the SEG is required as a future subject. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Eco-industrial parks (EIP) are clusters of industry corporations that collaborate with reusing waste and energy-efficient use of resources with no or minor impact on the environment. This paper presents a case study that examines the feasibility of using gas turbine technology in one industrial park, located in the Dongguan city of the Guangdong province in China. A model of a gas turbine-based combined heat and power (CHP) plant with a heat recovery steam generator for absorption cooling was developed and simulated. A steam-injected gas turbine has been selected in the system to increase electricity production and to generate steam. The study includes performance analysis of the cogeneration plant in terms of thermal efficiency, cost estimation, and greenhouse gas emission. The gas turbine-based cogeneration system has been compared with a baseline reference case that is defined as if all the energy to the industrial park is supplied from the local electricity grid. The results show that the gas turbine-based cogeneration system can reach a total efficiency of 58% and reduce CO2 emissions with 12 700 tons per year. A sensitivity analysis on the costs of the system has also been made based on fuel costs and the interest rate, which shows that the investigated system is economically profitable at natural gas prices below 4.4 RMB m-3 with fixed electricity prices and at electricity prices above 736 RMB MWh-1 with fixed natural gas prices. The sensitivity analysis based on the interest rate showed that the proposed system is economically feasible with interest rates up to 16%. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, by combining the equality differential increment theory (EDIT) with the equivalent polyhedron body (EPB) searching extremum strategy, a method of economical load dispatch for the steam turbine unit of the thermal power plant has been presented. Simultaneously, a method for the order of load shedding and the related optimal economic operational modes of each turbine unit in decreasing its load are ascertained. According to the methods, the results of the optimal economical dispatch of the peak loads, the order of load shedding and the related optimal economic operational modes of each turbine unit while decreasing the load of a certain thermal power plant have been obtained. These results are applied in the thermal unit, and its economic benefits are shown to be obviously higher than that of applying the relative efficiency of each turbine unit. The methods can be used as a reference for obtaining the optimum economical load dispatch for similar thermal power turbine units. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The independent fuel cell micro-grid that accommodates power and heat independently without connecting with other power systems is expected to back up power supply in an emergency, and at peak cuts of a power plant, and the effective use of exhaust heat is anticipated. Therefore, this paper analyses the cost minimization problem of the arrangement planning of a fuel cell system, and the feeding order of exhaust heat. An analysis programme for operation plan at the time of connecting a distributed fuel cell with an energy network was developed using a genetic algorithm. The fuel cell energy network was optimized in six buildings to minimize operation costs, facility costs, and the installation costs of the facilities. As a result, the analysis method for the arrangement plan for the capacity of each installed fuel cell, boiler, heat storage tank, and hot-water circulating pump was clarified. If the hot-water network of the distributed fuel cell is installed, in the winter of a cold district, facility cost is disadvantageous compared with the conventional method. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents a review and discussion of micro-fuel cell technologies, providing insight into the innovations that have been made to date. Discussion of concepts and results leading towards increased levels of integration and performance for micro-fuel cell systems will elucidate the potential of thin film and microfabrication methods in meeting the challenges and requirements necessary for consumer applications. While the amount of literature in this area is substantial, a representative sampling of key developments will be presented in this paper, in order to gain a sense of the design methodologies being implemented for micro-fuel cell power sources. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents exergy analysis of a conceptualized combined cogeneration plant that employs pressurized oxygen blown coal gasifier and high-temperature, high-pressure solid oxide fuel cell (SOFC) in the topping cycle and a bottoming steam cogeneration cycle. Useful heat is supplied by the pass-out steam from the steam turbine and also by the steam raised separately in an evaporator placed in the heat recovery steam generator (HRSG). Exergy analysis shows that major part of plant exergy destruction takes place in gasifier and SOFC while considerable losses are also attributed to gas cooler, combustion chamber and HRSG. Exergy losses are found to decrease with increasing pressure ratio across the gas turbine for all of these components except the gas cooler. The fuel cell operating temperature influences the performance of the equipment placed downstream of SOFC. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A fuel cell energy network which connects hydrogen and oxygen gas pipes, electric power lines and exhaust heat output lines of the fuel cell cogeneration for individual houses, respectively, is analysed. As an analysis case, the energy demand patterns of individual houses in Tokyo are used, and the analysis method for minimization of the operational cost using a genetic algorithm is described. The fuel cell network system of an analysis example assumed connecting the fuel cell cogeneration of five houses. If energy is supplied to the five houses using the fuel cell energy network proposed in this paper, 9% of city gas consumption will be reduced by the maximum from the results of analysis. Two per cent included with 9% is an effect of introducing water electrolysis operation of the fuel cells, corresponding to partial load operation of fuel cell cogeneration. [ABSTRACT FROM AUTHOR]

In this paper, the effect of natural organic matters (NOMs), which are typically present in river and seawater, on the power generation of reverse electrodialysis was studied. Bovine serum albumin, humic acid, and sodium alginate were used as models of NOMs. A NOM model was added to concentrated salt water, diluted salt water, and/or both of them. Power density was used to measure the resulted power generation. Fourier transform infrared spectroscopy and scanning electron microscope were used to characterize the presence of NOMs on the membrane surfaces. The effect of NOMs on the generated power density was clearly observed. This effect was influenced by the NOM's type, the NOMs concentration, and the compartment in which NOMs are added. Fourier transform infrared spectroscopy and scanning electron microscope data confirmed that NOMs are deposited on both anion and cation exchange membrane surfaces. While all NOMs added to concentrated salt water did not influence the generated power density, different power density behavior was resulted from the different NOMs added to diluted salt water, where NOMs could increase or decrease or remain the generated power density. Thus, besides NOM's type, the salt concentration is very critical to determine the effect of NOMs on the generated power density. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The installation of energy storage system to smooth the fluctuations of wind power output connected to the grid can effectively improve the electric quality and increase economic benefits of wind-generated electricity. Aiming at the overall profit maximization of wind power generation and storage system (WPGSS), taking the smoothing effect of active power output, the cost of hybrid energy storage system, and the earnings of wind power connected to the grid into consideration, this paper brings forward a game theory-based coordination and optimization control methodology for WPGSS adopting two low-pass filters to smooth the fluctuation of wind power output. The smoothing control to the active power of wind power and the power distribution of the hybrid energy storage system is respectively achieved by regulating the time constants of the two filters. With the combinations of wind power-batteries and wind power-super-capacitors as game's participants and the maximization of the WPGSS's overall profit as game's goal constraint conditions, game theory is introduced to realize the coordination and optimization between the time constants of the two filters. For comparative analysis, the model's optimal solution is respectively worked out by genetic algorithm and particle swarm optimization. The simulation results verify the effectiveness of the proposed method and provide a theoretical basis for the economic evaluation of the WPGSS. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: With ever increasing waste production worldwide, the development of newly emerging technologies is rising and advancing proportionately. Entailed instalment of sophisticated energy‐producing plants is constantly expanding to meet the socio‐economic demands of communities and industries. Innumerable superior technologies have been introduced to minimise waste pollution while reducing emissions of greenhouse gases hence, combatting the impact of global warming. This review shows energy conversion technologies including gasification, pyrolysis, incineration, landfill, and bioelectrochemical technologies mainly microbial fuel cell (MFC), microbial electrolysis cells (MECs) and microbial electrosynthesis (MES). Traditionally, incineration and landfill are the main mean of waste conversion but not favourable because of their side effects, economic viability, secondary pollution and difficulty in mechanical compression. Recently, biological processes including anaerobic digestion have gained huge interest but possess some inherent drawbacks and cannot provide a comprehensive solution for future waste management. Among energy converting technologies, bio‐electrochemical MFC system is highly preferred as an elementary, clean, safe, economically viable and environmentally beneficial technology. MFC a renewable energy technology possesses multidimensional applications of producing electric power and treat wastewater. In addition, the MFCs can be modified into MEC to generate hydrogen energy from various organic matters. Prospective modification recommendations for scale‐up application of this technology are also presented. [ABSTRACT FROM AUTHOR]

As electricity systems become increasingly dominated by variable inverter-based generation (such as wind and solar photovoltaics (PV)), additional sources of variability appear, while the share of dispatchable thermal power plants decreases. Maintaining a stable grid frequency requires new sources of inertia to slow the frequency changes, as well as new sources of reserve power to counter the imbalances. This work uses a linear optimization modeling approach to analyze the reserve market of the electricity system during the transition to a carbon-free system with high shares of variable electricity generation. The modeling is performed for three regional contexts and with varying degrees of available flexibility technologies. As for the reserve supply, batteries, electrolyzers, electric boilers and heat pumps for district heating, curtailed wind and solar power, and hydropower and thermal power plants are all included. The results indicate that of these suppliers of reserves, the introduction of grid-scale batteries into the system drastically reduces the reserve market size. Only early in the transition is revenue from the reserve market greater than 5% of the total revenue for any technology. While the demand for reserves increases as the share of solar PV and wind power increases, the modeling reveals that access to flexible loads, storage units, and emulated inertia from wind power also increases. Depending on the choice of flexibility measures available, demand-side participation could play a major role in minimizing the cost of grid stability in the future. [ABSTRACT FROM AUTHOR]

The current prevailing idea of tidal energy conversion is that it is presumed uneconomical to extract power from tidal flows of less than 2 m/s. As a result, there are a limited number of locations where energy from tidal flows can be exploited worldwide. Increasing the operating range of tidal energy devices to enable the extraction of useful power from low-velocity tidal flows would make tidal energy conversion possible in many more places around the world and greatly increase the potential global generating capacity. This paper presents a novel approach in extracting power from low tidal flows using vertical arrays of reduced diameter turbines. This has the effect of reducing the cut-in speed, increasing the operating range of the tidal energy device as well as the advantage of a lower cost, modular design, which addresses the issue of economical extraction at low flow rates. An assessment of the tidal energy resource around Hong Kong has been conducted for the preliminary stages of an ongoing tidal energy research project. The gathered data have been used to demonstrate the effectiveness of the presented concept in the Hong Kong region and other areas of low-velocity tidal flows. It has been demonstrated that a power increase of 40% is attainable from a vertical array of reduced diameter turbines when compared to a single, large-diameter device with the same frontal area. With the additional advantages of reduced cost of fabrication, installation, and maintenance from using smaller-diameter, modular tidal turbines, the concept is highly important to the advancement of global tidal power generation. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Global warming problem caused by greenhouse gas emissions from burning fossil fuels has caused wide public concern all over the world. This paper bases on renewable energy smart grid development as the background; the microgrid, power demand response, and vehicle to grid technologies are analyzed, and the basic structures and control strategies are also described. In order to transmit power from large-scale offshore wind farms and promote the utilization of renewable generation, the multi-terminal direct current (MTDC) based on voltage source converter (VSC) and solid state transformer are analyzed in detail, and the typical topologies and control methods are introduced. Finally, in order to improve the development of smart grid and VSC-MTDC in China, the microgrid park of the Institute of Electrical Engineering, Chinese Academy of Sciences, Yanqing direct current microgrid, and Nanao and Zhoushan VSC-MTDC are introduced. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Interconnected electricity networks, Supergrids, are being considered to help tackle some of the current global energy challenges such as rising CO2 emissions and the complete reliance on renewables. However, there are a range of obstacles associated with developing interconnections, not least the uncertainties associated with selecting appropriate countries with which to make interconnection. The process of identifying and then assessing various risks for these interconnections can be considered to be an important factor in mitigating and controlling their impact from within and outside national and international boundaries. To this end, this paper presents a risk-based framework to identify and assess the risks associated with developing new interconnections with other countries. Expert's knowledge and information available from the literature were used to identify 19 construction and 11 maintenance risks and to rank them using a 'risk' matrix. The usefulness of the approach is demonstrated using the UK as the case study. The analysis of the identified risks showed that regulatory framework, changes in energy policy and weak onshore grids require special attention and that, of those countries considered, Ireland was deemed to have the lowest risk for interconnection with the UK. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Wind power plant operators are often faced with extra charges when their power production does not match the forecasted power. Because the accuracy of wind power forecasts is limited, the use of energy storage systems is an attractive alternative even when large-scale aggregation of wind power is considered. In this paper, the economic feasibility of lithium-ion batteries for balancing the wind power forecast error is analysed. In order to perform a reliable assessment, an ageing model of lithium-ion battery was developed considering both cycling and calendar life. The economic analysis considers two different energy management strategies for the storage systems and it is performed for the Danish market. Analyses have shown that the price of the Li-ion BESS needs to decrease by 6.7 times in order to obtain a positive net present value considering the present prices on the Danish energy market. Moreover, it was found that for total elimination of the wind power forecast error, it is required to have a 25-MWh Li-ion battery energy storage system for the considered 2 MW WT. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we assess the total cost of energy recovery from sewage sludge through anaerobic digestion with biogas utilization in combined heat and power (CHP) system. The important advantage of anaerobic digestion process is the production of biogas, which can be used to generate electricity and heat as a source of renewable energy. From this study, it can be retained that the generated thermal energy from the anaerobic digestion process meets the needs of the wastewater treatment plant (WWTP) and guarantees its self-sufficiency in heat. The surplus of renewable heat produced by CHP is not a primary factor to improve the economic viability of the process. Moreover, the sales of electricity output represent about 76% of the operating costs of anaerobic digestion process. Renewable energy production is not economically viable by its own, without considering the wastewater treatment function and the associated incomes. Nevertheless, sludge digestion helps to reduce the wastewater treatment costs mainly by giving a good source of revenue via electricity production. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Energy consumption has risen in Malaysia because of developing strategies and increasing rate of population. Depletion of fossil fuel resources, fluctuation in the crude oil prices, and emersion of new environmental problems due to greenhouse gasses effects of fossil fuel combustion have convinced governments to invest in development of power generation based on renewable and sustainable energy (RSE) resources. Recently, power generation from RSE resources has been taken into account in the energy mix of every country to supply the annual electricity demand. In this paper, the scenario of the energy mix of Malaysia and the role of RSE resources in power generation are studied. Major RSE sources, namely biomass and biogas, hydro-electricity, solar energy, and wind energy, are discussed, focusing more toward the electrical energy demand for electrification. It is found that power generation based on biomass and biogas utilization, solar power generation, and hydropower has enough spaces for more development in Malaysia. Moreover, minihydropower and wind power generation could be effective for rural regions of Malaysia. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY There has been a growing interest in utilizing forest biomass for energy generation in district heating systems to reduce dependence on fossil fuels. However, variability in forest biomass availability and quality over time and its complex and costly supply chain have made investments in forest biomass energy generation projects less attractive. In this paper, a linear programming model is developed to minimize the delivery cost of forest biomass to the gate of heating plants and determine the optimal monthly flow of biomass to the plants. The model has a 1-year planning horizon with monthly time steps. It determines (1) the amount of woodchips that should be transported to the plants from supply sources directly and through the terminal storages, (2) the amount of biomass that should be stored at supply sources and at terminal storages, and (3) the amount of biomass that should be chipped at supply sources and at terminal storages. The model was applied to a potential district heating system in Williams Lake, BC, Canada. The results of the optimization model indicated that it would not be economical to carry out the chipping process at the terminal storage. Biomass should be chipped at supply sources, and woodchips should be sent to the terminal storage and/or directly to the plant. Of the total optimum annual flow of woodchips to the plant, 90% is transported directly, while 10% is transported to the plant via the terminal storage. It would cost $43.38 Odt−1 to deliver forest biomass to the plant. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Building cooling heating power (BCHP) systems as a kind of distributed energy resource have shown a great potential in improving energy efficiency and meeting multiple energy demands in buildings. In this paper, we present a BCHP system driven by solar energy with flat-plate solar collectors. A modified system efficiency is introduced to evaluate the whole day performance of the system more accurately. Based on the mathematical models and simulation platform established, we have investigated the influences of some key thermodynamic parameters, namely condensation temperature, turbine inlet temperature and turbine inlet pressure on the system performance. In order to find the optimum combination of these parameters that leads to the best performance, we have performed parametric optimization by means of the genetic algorithm. Results indicate that the best performance and the highest efficiency of the system are achieved when the working fluid reaches its saturated state and the corresponding efficiencies of the system operating in the combined heating power mode, the combined cooling power mode and the power production mode turn out to be 19.10%, 27.24% and 10.47%, respectively. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Reunion Island is heavily dependent on fossil fuels, but seeks to become energy self-sufficient by 2025. ocean thermal energy conversion provides a means of producing electricity that harnesses the available energy of the ocean by using the temperature gradient between its deep and its upper layers. This paper presents the projected experimental facility which is to be installed at the University of St. Pierre on Reunion Island. A dynamic model of the installation has been developed (on a Delphi interface) by using the concept of equivalent Gibbs systems. In such equivalent system, mass, energy, and entropy are linked through the Gibbs equation, and the entropy production can easily be expressed in terms of fluxes and their related forces. Assuming linear phenomenological laws, the phenomenological coefficients are assessed from technical data. Using a digital tool (Genopt), an optimization study has been conducted in order to determine the best operating parameters according to the temperature of the sea water. This model allows us to anticipate the potential of this technology on Reunion Island. Once validated on the facility, the model will serve as a tool to assist design of the future 10 MW pilot plant planned for 2014. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Bagasse is selected as the biomass source that is studied because of its annual significant rate production in Iran and potential for energy generation. Bagasse has been as an energy source for the production of energy required to run the sugar factory. The energy needed by factories was supplied by burning bagasse directly inside furnaces, which had an exceptionally low output. To this end, today, a secondary use for this waste product is in combined heat and power plants where its use as a fuel source provides both heat and power. In addition, low efficiency of traditional methods was caused to increase the use of modern methods such as anaerobic digestion, gasification and pyrolysis for the production of bio-fuels. In this paper, the energy conversion technologies are compared and ranked for the first time in Iran. Therefore, the most fundamental innovation of this research is the choice of the best energy conversion technology for the fuel production with a higher efficiency. To assess the feasibility application and economic benefit of biogas CHP plant, a design for a typical biogas unit is programmed. The results show the acceptable payback period; therefore, economically and technically, biogas CHP plant appears to be an attractive proposition in Iran. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]