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The coupling between modern electric power physical and cyber systems is deepening. An increasing number of users are gradually participating in power operation and control, engaging in bidirectional interactions with the grid. The evolving new power system is transforming into a highly intelligent socio–cyber–physical system, featuring increasingly intricate and expansive architectures. Demands for stable system operation are becoming more specific and rigorous. The new power system confronts significant challenges in areas like planning, dispatching, and operational maintenance. Hence, this paper aims to comprehensively explore potential synergies among various power system components from multiple viewpoints. It analyzes numerous core elements and key technologies to fully unlock the efficiency of this coupling. Our objective is to establish a solid theoretical foundation and practical strategies for the precise implementation of integrated planning and operation dispatching of source–grid–load–storage systems. Based on this, the paper first delves into the theoretical concepts of source, grid, load, and storage, comprehensively exploring new developments and emerging changes in each domain within the new power system context. Secondly, it summarizes pivotal technologies such as data acquisition, collaborative planning, and security measures, while presenting reasonable prospects for their future advancement. Finally, the paper extensively discusses the immense value and potential applications of the integrated planning and operation dispatching concept in source–grid–load–storage systems. This includes its assistance in regards to large-scale engineering projects such as extreme disaster management, facilitating green energy development in desertification regions, and promoting the construction of zero-carbon parks. [ABSTRACT FROM AUTHOR]

In the contemporary global discourse on environmental and developmental issues, the dual challenges of sustainable green energy and water supply stand paramount. These elements are vitally intertwined with the socio-economic vitality of the world. Notably, regions plagued by freshwater scarcity are increasingly turning to desalination which consists of a reliable and unconventional water source. The intersection of renewable energy with desalination and water purification processes presents a compelling synergy. This approach is particularly pertinent in areas where freshwater shortages coexist with abundant solar energy availability. Additionally, these technologies boast the advantage of low operational and maintenance costs. This paper delves into the design, optimization and financial analysis of a novel, standalone hybrid energy system, integrating photovoltaic and fuel cell technologies, for an agriculture farm situated in Kairouan, Tunisia. Unlike conventional systems, this model foregoes battery storage in favour of hydrogen storage, generated through water electrolysis powered by solar energy. This system harnesses solar energy for direct electrical power generation and hydrogen gas production. A segment of the generated electricity is allocated to electrolysis for green hydrogen production. In times of solar unavailability, the stored hydrogen is reconverted to electricity via a fuel cell. An intriguing aspect of this system is the utilization of saline well water, which, due to its high salt content, necessitates purification through desalination to prevent damage to the electrolysis unit and to render it suitable for agricultural irrigation. [Display omitted] • The production of green hydrogen, water and electricity for agriculture farm in Tunisia is analyzed. • The Levelized cost of green hydrogen produced in the PV farm is 2.25 €/kg. • A PV hydrogen Farm station with a capacity of 140 kW produces 1991 kg of green hydrogen and 235 MW h of electricity yearly. [ABSTRACT FROM AUTHOR]

It is crucial to explore new green energy sources to alleviate the earth's energy depletion and the impact of air pollution and greenhouse effects. Although wafer manufacturing is increasing worldwide, the implementation of carbon footprint policies necessitates a shift toward green electricity. To expand the scale of wafer manufacturing, it is essential to develop terrestrial green electricity, which requires additional terrestrial green energy sources. This paper presents a green energy harvesting method that generates wave hydraulic energy via a vibration-based electromagnetic generator through a buoy. An energy harvester composed of two magnets in series driven by a buoy via a connected pole is introduced. The sensitivity of induced electricity to the energy harvester's design parameters, including the magnets' geometric dimensions (diameter and height), the coil's turns, and layers, is analyzed. Additionally, the relationship between electricity and wave information (wave amplitude and wavelength) is explored. To evaluate the electrical power efficiency between a pair of single-magnet energy harvesters and the two-magnet harvester, a pair of parallel energy harvesters consisting of one magnet and paralleled in line is assessed. The impact of electricity on the horizontal span between the parallel energy harvesters is also investigated. To achieve maximal electricity, the two-magnet energy harvester is numerically optimized using a simulated annealing method. The numerical result shows that the two-magnet (in series) energy harvester can produce 0.472 W when the wavelength is 0.03, the amplitude is 0.09 m, and the wave speed is 3 m/s. [ABSTRACT FROM AUTHOR]

In this research paper, a new research path was opened with a new scientific view and a new philosophy for the goals of crude oil production through the development of important joints in the production process of crude oil where a horizontal three-phase separator was developed to produce green electrical energy without the need for combustion processes by creating a design for rotating parts capable of converting the momentum of the flow into electrical energy, the first part is the rotating diverter, which collides with the input mixture, which leads to a reduction in the momentum of the flow and an initial separation of gas from liquid, the collision results in the rotation of the wheel on which the concave bowls are installed, and thus generates electrical power by the dynamo connected to it. The second part of the separator that has been developed is to add a cone-shaped rotating external mist extractor with helical fin to perform two functions at the same time separating suspended liquid particles from the gas and generating clean electric power by the dynamo connected to it when it rotates under the influence of gas pressure. The efficiency of the developed separator parts was tested in performing their traditional function to separate the different phases and it was found that the developed separator is more efficient in addition to its ability to generate clean energy. [Display omitted] • A new vision for the purpose of investing in hydrocarbon fuels and develop production equipment. • The study of generating green electric power from crude oil and natural gas without combustion. • The rotating parts in the upgraded separator to make it more efficient in separating the three phases gas,oil,water. [ABSTRACT FROM AUTHOR]

People are increasingly using clean energy sources, contributing to environmental protection according to the general trend of the world. In the form of renewable energy, solar energy has contributed to solving current pressing problems, such as environmental pollution and air pollution, improving people's quality of life. The design of solar power projects in Vietnam is mainly based on meteorological data sources from Meteonorm and NASA. However, the accuracy assessment of two data sources compared to the actual solar power data in Vietnam is not available, so there is no basis to determine better meteorological data source quality to serve the design of rooftop solar power projects. The content of this paper analyzes the simulation results of a typical rooftop solar power station at the Electric Power University, Hanoi city based on meteorological data sources from Meteonorm and NASA. After that, the simulation results will be compared with the actual operating data of a rooftop solar power station near the Electric Power University and other real PV systems in the world. The study results showed that the amount of electricity production using the Meteonorm meteorological data was closer to the actual data than the NASA data source. Therefore, solar power projects in Vietnam should use Meteonorm data source for the design process to determine the best economic and technical efficiency for investors. [ABSTRACT FROM AUTHOR]

This study discusses how to increase power quality by integrating a unified power quality conditioner (UPQC) with a grid-connected microgrid for clean and efficient power generation. An Artificial Neural Network (ANN) controller for a voltage source converter-based UPQC is proposed to minimize the system's cost and complexity by eliminating mathematical operations such as a-b-c to d-q-0 translation and the need for costly controllers such as DSPs and FPGAs. In this study, nonlinear unbalanced loads and harmonic supply voltage are used to assess the performance of PV-battery-UPQC using an ANN-based controller. Problems with voltage, such as sag and swell, are also considered. This work uses an ANN control system trained with the Levenberg-Marquardt backpropagation technique to provide effective reference signals and maintain the required dc-link capacitor voltage. In MATLAB/Simulink software, simulations of PV-battery-UPQC employing SRF-based control and ANN-control approaches are performed. The findings revealed that the proposed approach performed better, as presented in this paper. Furthermore, the influence of synchronous reference frame (SRF) and ANN controller-based UPQC on supply currents and the dc-link capacitor voltage response is studied. To demonstrate the superiority of the suggested controller, a comparison of percent THD in load voltage and supply current utilizing SRF-based control and ANN control methods is shown. [ABSTRACT FROM AUTHOR]

Electric power shortfalls driven by inadequate generation, electrification, and lack of clarity on the planning side have worsened Pakistan's power crises that deformed economic growth. This study focuses on the estimation of the electricity supply and demand in the China-Pakistan Economic Corridor (CPEC) perspective and on the main reasons that motivate a transition to green resources. This paper estimated the demand-supply gap (1990–2015) and forecasted it (2016–2035), including CPEC projects using the System Dynamics model. The results show that the power demand will be met by 2021, fact highlighted also by a battery of robustness tests. We find that the CPEC efforts will increase energy growth from 4.5% (1990–2015) to 14.6% (2016–2035). The capacity growth will increase from 4.9% to 12.3% during 2016–2035. Moreover, the current renewable energy production and investment (Wind & Solar Power) will not help achieve policy targets. A total investment of $4806.69 million is required to meet policy targets, while a value of $57,683 million is needed for a complete conversion to green energy. The study highlights the challenges on the green energy path and discusses policies needed to overcome these problems. [ABSTRACT FROM AUTHOR]

Despite a substantial potential of renewable energy sources, the current energy supply system in Iran relies almost entirely on fossil fuel resources. It has imposed significant financial burden on the country and has led to considerable GHG emissions. Moreover, the country is confronting several challenges for harnessing alternative clean energy sources and promoting rational energy policies over the recent decades. To probe the root cause of these problems, this paper first provides an overview on the previous energy planning attempts in Iran. It shows that adequate commitment to a long-term energy planning could have meaningfully prevented these serious challenges. However, the previous studies have had some limitations in terms of employing appropriate planning tools, comprehensive evaluations, and scenarios definition and ranking. This paper thus proposes a power planning framework to assess the sustainability of future electricity scenarios for the period 2015–2050. MESSAGE, a systems engineering optimization model, is employed to evaluate the potential impacts of transitioning to a low-carbon electricity supply system. Using a combined AHP-TOPSIS method, the scenarios are then ranked based on 18 different techno-economic, environmental, and social dimensions of sustainability. The results indicate that scenario Cl_32, in which the share of non-hydro clean energy for electricity generation reaches 32%, is ranked best. • Iran's energy planning studies are reviewed. • A suitable link between energy planning and policy making is necessary for Iran. • A framework for sustainable development of the power sector is proposed. • MCDM is used to assess the sustainability of different scenarios. • The share of non-hydro clean energy technologies should increase up to 32% by 2050. [ABSTRACT FROM AUTHOR]

With the comprehensive progression of China's electric power reform, the participation of hydropower in the spot market has become inevitable. For hydropower-dominated power grids, the tight hydraulic and electric coupling relationship between cascade hydropower plants and the policy requirement of clean energy consumption greatly increase the challenge of optimal scheduling. Based on the market characteristics and actual demand of the hydropower-dominated power grids, this paper discusses the day-ahead spot market trading mechanism to promote the guaranteed consumption of renewable energy. On this basis, a day-ahead optimal scheduling model is established which aims to minimize the comprehensive power purchase cost of the power system. The nonlinear factors in the scheduling model, such as the relationship between the water level and storage capacity of hydropower plants, the relationship between the water level and water consumption rate, and the constraints on the start-up and shutdown durations of thermal power units, are linearized through multiple linearization techniques. The original nonlinear model is transformed into a mixed integer linear programming (MILP) model and is then solved using a CPLEX solver. The developed model is verified by taking 10 thermal power plants and 22 hydropower plants in Yunnan Power Grid as a case study. The calculation time is 183.6s, the comprehensive power purchase cost of the system is 155.35·million CNY, and no abandoned water is generated in the three basins. The simulation results show that the proposed model has high solution accuracy and efficiency, and maximizes the hydropower consumption under the premise of meeting the minimum comprehensive power purchase cost. The findings of this study can provide a scientific basis for the development of the day-ahead spot market of hydropower-dominated power grids. [Display omitted] • A day-ahead spot market trading mechanism to promote consumption of renewable energy. • Day-ahead optimal scheduling of hydropower-dominated power grids under a spot market environment. • A novel MILP approach is employed to solve the model. • Proposed model has high solution accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Piezoelectric cantilever beams, which have simple structures and excellent mechanical/electrical coupling characteristics, are widely applied in energy harvesting. When the piezoelectric cantilever beam is in a wind field, we should consider not only the influence of the wind field on piezoelectric beam but also the electromechanical coupling effect on it. In this paper, we design and test a wind-induced flag-swing piezoelectric energy harvester (PEH). The piezoelectric cantilever beam may vibrate in the wind field by affixing a flexible ribbon to the free end as the windward structure. To fulfill the goal of producing electricity, the flexible ribbon can swing the piezoelectric cantilever in a wind-induced unstable condition. The experimental findings demonstrate that the flag-swing PEH performs well in energy harvesting when the wind field is excited. When the wind speed is 15 m/s, the peak-to-peak output AC voltage may reach 13.88 V. In addition, the voltage at both ends of the closed-loop circuit's external resistance is examined. The maximum electric power of the PEH may reach 43.4 μW with an external resistance of 650 kΩ. After passing through the AC-DC conversion circuit, the flag-swing PEH has a steady DC voltage output of 1.67 V. The proposed energy harvester transforms wind energy from a wind farm into electrical energy for supply to low-power electronic devices, allowing for the creation and use of green energy to efficiently address the issue of inadequate energy. [ABSTRACT FROM AUTHOR]

Spectral splitting photovoltaic/thermal technology is the leading field in the area of extremely efficient utilization of solar energy. Due to its complexity, experimental research on spectral splitting photovoltaic/thermal devices is relatively limited, mainly focusing on the laboratory scale energy efficiency test or calculation process verification. These studies do not provide intuitionistic guidance for the actual operation of engineering systems. In this paper, a fluid filter-based compound parabolic concentrator solar photovoltaic/thermal system with engineering application dimensions is designed and experimentally studied under actual outdoor environments. Different fluid filters are prepared and used to regulate the spectral splitting characteristics of the proposed system, including the deionized water, silver/water nanofluids and silver-cobalt sulfate/water nanofluids. When the environmental parameters are relatively stable, the method of adjusting the composition of the fluid filter is used to obtain the dynamic operating characteristics of the system. The results show that silver nanoparticles and cobalt sulfate can improve the spectral absorptivity of the deionized water. Compared with the deionized water, when the silver/water nanofluids is used as the fluid filter, the thermal efficiency of the system increases, the electric efficiency and overall exergy efficiency of the system both decrease, and the three efficiencies are 56.0%, 8.5% and 19.6%, while for the silver-cobalt sulfate/water nanofluids, the efficiencies are 58.0% 8.0% and 20.0%. Moreover, the results reveal that for the photovoltaic/thermal system with a low solar concentration ratio, by enhancing the absorptivity of the fluid filter, the fill factor of the photovoltaic module can increase, but the output electric power will decrease. When the silver-cobalt sulfate/water nanofluids is used, the fill factor and maximum output power of the proposed system are 0.633 and 69.2 W. For a unit consisting of four sets of the proposed photovoltaic/thermal systems, the emission reductions of CO 2 , NO x , SO 2 and dust for the whole lifetime are approximately 7794.19 kg, 181.48 kg, 191.95 kg and 111.68 kg, respectively. [ABSTRACT FROM AUTHOR]

Deep borehole heat exchanger (DBHE) extracts heat from mid-deep geothermal energy through heat transfer process. As DBHE commonly applies coaxial borehole heat exchangers with depth of 2–3 km, the volume reaches more than 30 m3, similar to the small heat tank underground. When the heat pump system turns off, the water in DBHE still extracts heat from the high-temperature ground and stores heat. This kind of heat storage characteristic of DBHE was studied in this paper with simulation analysis. Benefiting from the heat storage characteristic, the average heat extraction rate (Q r) of DBHE under intermittent operation is 8.6%–64.7% higher than Q r under continuous operation, with run-stop ratio decreasing from 24 to 0 to 8–16 per day. Then the influence of operation modes, parameters and thermo-physical properties of DBHE on the heat storage characteristic were studied quantitatively, proving the wide-range regulation ability of Q r. Therefore, the regulation ability of DBHE matches the variation of space heating load very well, and also matches the production rules of clean electric power like photovoltaic and wind power. Hence, the DBHE could further participate in the demand response of electrical power system, and absorb clean electric power. • The heat storage characteristic of deep borehole heat exchangers (DBHEs) was studied. • The heat storage characteristic improves the transient heat extraction rate obviously. • Operation modes and parameters influence the heat storage performance greatly. • The DBHEs have wide-range regulation ability of transient heat extraction rate. [ABSTRACT FROM AUTHOR]

After the strategic concept of global energy Internet constructed, it has produced a strong response in the world. In recent years, countries around the world are actively promoting energy transformation and have developed clean energy development goals and plans. This paper constructs a comprehensive evaluation index system for the level of clean energy development by considering policies and regulations, energy supply, environmental impact, energy consumption, technology, economy and so on. At the same time, China, Germany, the United States and other countries are selected as evaluation objects. On the basis of searching, processing and analyzing a large number of data, firstly, the research uses the principal component analysis method to carry out the correlation cluster analysis of the index and then uses the rough set method to assign the weight of the extracted principal components. Finally, the weight of each index in the index system is calculated. The results of the comprehensive evaluation of each country are compared and analyzed, which shows that the weight determination method based on rough set theory and principal component analysis is more reasonable and objective. At the end of the paper, some suggestions are proposed to promote the development of clean energy. [ABSTRACT FROM AUTHOR]

This paper introduces an enhanced version of Concentrating Photovoltaic Glazing (CoPVG) device. The original CoPVG system was designed as a seasonal glazing, that concentrates sunlight onto the focus of the lens during summer. Whilst, in winter, the system transmits light for indoor daylighting purposes. The newly developed version, entitled Concentrating Photovoltaic/Thermal Evacuated Glazing (CoPVTEG), is capable of simultaneously harvesting thermal energy and electricity while vacuum glazing (VG) has been integrated into the device. A finite element method was employed to simulate the glazing computationally. The developed model was validated by conducting experiments verifying that the model predicts the glazing performance reliably. Two different configurations were considered: placing the VG facing either outside, called disposition A, or inside, called disposition B. These dispositions were analysed computationally to determine the thermal and electrical output powers of the device in Belfast, UK. It was found that locating the VG inside potentially doubled the output electrical power ranging from 63.32 W/m 2 to 92.56 W/m 2 and from 36.03 W/m 2 to 43.88 W/m 2 at noon throughout the year for disposition B and A, respectively. However, the thermal harvesting potential of disposition A is higher than disposition B. In this case, the device potentially generates from 216.46 W/m 2 to 406.20 W/m 2 thermal power at noon. While the potential will be reduced from 163.54 W/m 2 to 396.11 W/m 2 in disposition B. Disposition A is more advantageous for cold-dominant climate zones while disposition B is the suggestion for temperate climate zone like the studied case. • This study presents Concentrating Photovoltaic/Thermal Evacuated Glazing, a semi-transparent and energy-efficient building façade. • The device serves multiple functions by not only passively managing energy, but also generating clean electricity and heat. • An experiment campaign was conducted to characterize the concept and validate a FEM model. • This research investigates the interaction of vacuum glazing and its placement within the device. [ABSTRACT FROM AUTHOR]

Operation of distributed energy resources and resilience related problems are becoming of most importance in the pursuit for a more sustainable electricity delivery. Microgrids (MGs) could contribute significantly to both issues and may play an important role in the new decentralized paradigm of power systems. This paper proposes a hierarchical organizational scheme of MGs with a clear distinction of the Microgrid, Nanogrid and Picogrid concepts, and addresses a detailed technical literature review to identify and classify MGs main features and design alternatives. Definitions; descriptions of MGs, Nanogrids, Picogrids; operation modes; business models and communication protocols are dispersed in the literature. In order to gather clearly all the existing information, this review has been organized according to four functional layers, inspired by the ones commonly used in Smart Grid architecture description. For each one and whenever possible, the paper classifies the outcomes of the review in a table kind of format that helps summarizing the different MGs׳ options. Regarding the first layer, the paper describes the different physical devices involved in MGs, such as generators, converters, electric vehicles (EV) and energy storage systems (DS) and the DC levels that are being discussed. For the second layer the paper addresses a review of the communication protocols currently used or proposed. Then, the intelligence layer is analyzed concerning any decision making issue related to operation and planning of the MGs as well as any other aspect that may be relevant for taking advantage of MGs potentiality. In the last layer, the paper reviews different business models adapted to a future where MGs will be deployed. Finally, the paper ends with an exhaustive review of the practical MG experiences in place worldwide, classified according to the issues presented previously, and a brief discussion of the key points to be addressed in the MGs deployment. [ABSTRACT FROM AUTHOR]

Abstract Worldwide, the demand for energy has increased significantly in last two decades, leading to an increased use of non-renewable energy resources. The global agenda aims to reduce the carbon intensity of energy in long-term climate change mitigation strategies, and to achieve Sustainable Development Goal 7 (SDG-7) on affordable and clean energy. Use of renewable energy (RE) can contribute to reducing global greenhouse gas (GHG) emissions while providing incremental financial resources to stimulate clean development mechanisms. Hydropower continues to be the leading RE option and has the additional benefits of water storage for agriculture and other uses. Drawing on the position of four Hindu Kush Himalayan (HKH) countries – Bangladesh, India, Nepal and Pakistan – this paper investigates the current status of hydropower generation and related policies, and attempts to identify the key challenges to and opportunities for hydropower development in the region. Collectively, four HKH countries have commercially feasible hydropower potential of nearly 190 GW. However, only one-third of this potential has actually been tapped so far. Nepal and Pakistan have tapped 2% and 12%, respectively, of their hydropower potential. The current hydropower supply has not been able to fulfill the electricity demand in the region, where 26–37% of the rural population is living without access to electricity, and future demand for electricity is likely to increase sharply. There are several economic, social, technical, environmental, ecological and political challenges to hydropower production in the HKH countries. Despite these challenges, hydropower remains an important option for achieving renewable energy goals in the region. To achieve these goals, we suggest capitalizing on emerging opportunities such as large hydropower development using a 'smart approach', micro-hydropower promotion, energy trade, and regional cooperation for collective energy development programs. [ABSTRACT FROM AUTHOR]

In this paper, a new virtual framework for load aggregation in the context of the liberalized energy market is proposed. Since aggregation is managed automatically through a dedicated platform, the purchase of energy can be carried out without intermediation as it happens in peer-to-peer energy transaction models. Differently from what was done before, in this new framework, individual customers can join a load aggregation program through the proposed aggregation platform. Through the platform, their features are evaluated and they are clustered according to their reliability and to the width of range of regulation allowed. The simulations show the deployment of an effective clustering and the possibility to meet the target power demand at a given hour according to each customer's availability. [ABSTRACT FROM AUTHOR]

A novel passive thermoelectric system based on radiative cooling and solar heating is designed for continuous power generation during a full 24-hour day - even in winter. An evaluation model is established to determine the temperature difference between the TEG ends and calculate the system output. The seasonal all-day performance and output map of the system in China are presented. Results indicate that the proposed passive TEG system that integrates radiative cooling and solar heating can produce 24-hour continuous and impregnable output with a maximum of 3.29 W·m−2 in China. [Display omitted] • A passive TEG system integrating radiative cooling and solar heating is proposed. • Theoretical model for evaluating the 24-hour system performance is established. • Effects of radiative cooler, solar absorption rate, and cloud cover are studied. • Seasonal performance and the output map of the passive system are presented. • The output power of the passive system can reach 3.29 W·m−2 in China. Harvesting energy from the sun and ultracold outer space for electricity generation is green access to green energy and helps reduce carbon dioxide emissions. However, current work on passive electricity generation is restrained to daytime or nighttime. In this paper, we propose a passive thermoelectric system that produces continuous electric power during a full 24-hour day - even in winter. The thermoelectric output is maintained and amplified by integrating radiative cooling and solar heating. The utterly passive system consists of a thermoelectric generator (TEG), a radiative cooling film, and a greenhouse cavity. Radiative cooling is used to cool the sky-facing end of the TEG below ambient temperature without the need for fuel. Meanwhile, the solar-heating-based greenhouse is used to heat the hot end of the TEG to enhance the temperature difference between the cold and hot ends and, thus, the output. An energy balance model that considers the varying solar radiation is developed to determine the temperature difference between the TEG ends and system output. The accuracy of the evaluation model is first confirmed by the good agreement between the modelled performance of the system and the experimentally measured data. Afterwards, the effects of radiative cooler, solar absorption rate, and cloud cover on the system performance are studied. Finally, the seasonal and locational performance of the system in China is evaluated. Results indicate that the proposed passive TEG system that integrates radiative cooling and solar heating can produce 24-hour continuous and impregnable output. Therefore, the proposed system in this work may help the development of passive electricity generation. [ABSTRACT FROM AUTHOR]

In the view of pressing unemployment and environmental problems, different policies have been proposed to create jobs in the transition to a green economy, including the so-called “green jobs”. There has been an intense debate on the quantification of these employment effects, especially in the European Union. Most studies have focused on estimating gross future employment effects and have ignored the effects between different sectors and countries. This paper looks, for the first time, at the past net employment impacts from the transformation of the EU energy sector including spill-over effects, by using a multi-regional input–output model and the World Input–Output Database. The analysis is focused on the period (1995–2009) when the EU’s energy structure went through a significant shift, away from the more carbon intensive sources, towards gas and renewables. We estimate the net employment generated from this structural change at 530,000 jobs in the EU (0.24% of total employment in 2009), of which one third is due to trans-boundary effects within the EU (i.e. employment generated in one country due to the changes in another). Within the EU, the main gainers were Poland, Germany, Hungary, Italy and Spain, and the main losers were Ireland, Lithuania, France and Czech Republic. [ABSTRACT FROM AUTHOR]

This paper explores the key issues of environmental and social governance (ESG) issues and identifies the main ESG themes for companies in the power industry: sustainable development of green and clean energy, energy conservation and emission reduction, physical and mental safety of professionals, global climate change mitigation, supply chain management, community relationships, responsible governance. In-depth research and comparison are carried out on the related issues of sustainable development. Through validation, it is shown that these issues can have further solutions on ESG issues. Compared to other industries, the number of companies working on AI clean energy has increased by about 25%. In the artificial intelligence management of exhaust emissions, it will be reduced by about 20% than before. After using artificial intelligence, the health index of employees increased by about 4% year-on-year. Enterprise management efficiency has also increased by about 6%. This also shows that in the age of artificial intelligence, everything will be improved. [ABSTRACT FROM AUTHOR]

The price consumers are willing to pay (WTP) extra for green electricity (GE) is one of the uncertainties possibly impacting on the overall feasibility of its market introduction. In the literature, several measurements of WTP are used. However, the number of studies comparing WTP measures is limited. This study investigates the construct validity (convergent and theoretical) of two widely used WTP measures (double-bounded dichotomous choice (DC) and open-ended (OE)). A model informed by the well-known theory of planned behaviour was applied to survey data from 890 South African domestic energy users. It was found that convergent validity among the WTP measures was fairly low. Moreover, results from Tobit regressions showed that a grounded theoretical model yields statistically significant results. However, different independent variables emerge in the DC and OE models. Therefore, the theoretical validity of one of the WTP measures seems to be low. The paper proposes a number of explanations for the low construct validity observed. [ABSTRACT FROM AUTHOR]

SUMMARY Reducing the rates of nuclear power generation for all electric power sources has been seriously discussed in Japan since the accident at the Fukushima No. 1 nuclear power plant in March 2011. Thus, the distributed power supply is expected to expand. The local production of safe and clean energy for local consumption is greatly needed in Japan. In this paper, the Saroma Lake green microgrid (SLMG), a fuel cell microgrid using tidal power generation and photovoltaics, has been planned. Energy balance equations were used to investigate this system's method of operation. Further simulated analysis of the facility, its operation cost, and the electric power quality of the network were conducted using MATLAB/Simulink, and the relationships among the capacity of a facility, the cost, and supply rate of green energy and the electric power quality (interphase voltage, frequency, and higher harmonic wave) of the power network were clarified. The total projected cost of the equipment and operation for introducing the proposed SLMG is ¥1,500,000,000/10 years. Increasing the supply rate of green energy and reducing the facility cost will require the introduction of biofuels and the reduction of the facility costs of solid oxide fuel cells in the SLMG. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hydrogen is having a worldwide momentum as a clean versatile energy solution and this is the time for nuclear hydrogen production technologies to play its role in securing a clean and affordable energy future. For over four decades, several nations have been investigating the potential of tens of thermochemical cycles for efficient and sustainable hydrogen production. These cycles require high quality heat (i.e. heat at high temperatures) solely or along with electric power (i.e. hybrid thermochemical cycles) both of which can be provided by nuclear energy. This paper delivers a highlight on the potential of nuclear energy for hydrogen production. It also discusses the main features of five of the promising thermochemical cycles that are considered for integration with nuclear power plants. Furthermore, the paper highlights the current status and advances of R&D in these thermochemical cycles as well as cost estimation and the main safety consideration for large-scale nuclear hydrogen production using different nuclear-driver technologies. [ABSTRACT FROM AUTHOR]

• Frequency-watt, volt-watt, and power curtailment methods were analyzed using smart PV inverters. • Power curtailments were discussed at low and high PV penetration areas. • Effects on the distribution voltage are described at the service transformer level. • Control performances were evaluated. • Experimental analyses were performed at the Maui Smart Grid project, Hawaii. Large-scale deployments of variable renewable energy sources, such as photovoltaic (PV) systems, are increasing around the world. PV systems are a potential source of clean energy but they experience power intermittency and lack controllability. However, smart PV inverters provide grid-friendly functionalities that control the power output of PV systems. Power intermittency of PV systems causes major problems such as voltage fluctuations and frequency deviations in an electric power grid. Together with varying loads and other renewable distributed generations, the grid frequency and voltage become difficult to manage. A smart PV inverter allows for active power curtailment, volt-watt, and frequency-watt control systems to mitigate the voltage and frequency deviations for a smart power grid. Therefore, smart PV inverters can reduce the installation of voltage and frequency control devices in an electric power grid, which in turn can reduce installation and maintenance costs. Real-time analyses of active power curtailment, volt-watt control, frequency-watt control using smart PV inverters and their effects on voltage and frequency are presented in this paper. Power curtailment operations were executed in low and high PV penetration areas. From the experimental analyses, distributed voltage deviations can be mitigated using active power curtailment and volt-watt control systems, and the over-frequency of an electric power grid can be reduced using frequency-watt control method. Controller performances of smart PV inverters are also evaluated in this paper. The experimental analyses were executed in the Maui Advanced Solar Initiative Project. [ABSTRACT FROM AUTHOR]

In the last few decades, nuclear energy has become an important source of energy because it is seen as a low intensity carbon energy alternative to reduce environmental pollution. However, nuclear energy has many hazards to both the environment and human life. This paper examined the status, opportunities, and challenges of nuclear electric power, with emphasis on issues of energy security, safety and occupational health implications for Sub-Sahara Africa and particularly Ghana. The findings of the review suggest that Ghana could be supported by the International community with technical and human competencies required to effectively develop and run a nuclear energy project. However, there is the need to have clear-cut health, regulatory, occupational health and safety policies and procedures for the nuclear programme. Further, maintaining and strengthening economic and political institutions for nuclear programme more specifically and the overall national economy will be critical for the success of the nuclear energy programme. This will obviously require first and foremost the passage of the occupational health and safety bill into law and its implementation to ensure safe and clean energy. Additionally, the review shows that nuclear power should not be seen as a substitute but a complement to other renewable energy sources to reduce energy poverty and promote sustainable development. • Nuclear energy is an important source of energy. • Nuclear waste has both negative effect on both the environment and human lives. • Opportunities exist for African countries to explore nuclear technology. • Ghana is on course to develop Nuclear power with support from the international community. • Regulatory, technical competencies and safety measures are critical for the success of nuclear programme. [ABSTRACT FROM AUTHOR]

The load shifting strategy is a form of demand side management program suitable for increasing the reliability of power supply in an electrical network. It functions by clipping the load demand that is above an operator-defined level, at which time is known as peak period, and replaces it at off-peak periods. The load shifting strategy is conventionally performed using the preventive load shifting (PLS) program. In this paper, the corrective load shifting (CLS) program is proven as the better alternative. PLS is implemented when power systems experience contingencies that jeopardise the reliability of the power supply, whereas CLS is implemented only when the inadequacy of the power supply is encountered. The disadvantages of the PLS approach are twofold. First, the clipped energy cannot be totally recovered when it is more than the unused capacity of the off-peak period. The unused capacity is the maximum amount of extra load that can be filled before exceeding the operator-defined level. Second, the PLS approach performs load curtailment without discrimination. This means that load clipping is performed as long as the load is above the operator-defined level even if the power supply is adequate. The CLS program has none of these disadvantages because it is implemented only when there is power supply inadequacy, during which the amount of load clipping is mostly much smaller than the unused capacity of the off-peak period. The performance of the CLS was compared with the PLS by considering chronological load model, duty cycle and the probability of start-up failure for peaking and cycling generators, planned maintenance of the generators and load forecast uncertainty. A newly proposed expected-energy-not-recovered (EENR) index and the well-known expected-energy-not-supplied (EENS) were used to evaluate the performance of proposed CLS. Due to the chronological factor and huge combinations of power system states, the sequential Monte Carlo was employed in this study. The results from this paper show that the proposed CLS yields lower EENS and EENR than PLS and is, therefore, a more robust strategy to be implemented. [ABSTRACT FROM AUTHOR]

California is a pioneer in energy system innovations, and it is not surprising that the state is leading the nation in the adoption of microgrids. However, the inherent characteristics of microgrids make them challenging to integrate and operate within the current energy system. This is mainly because unlike other decentralized energy systems, microgrids often tend to interact with the centralized grid infrastructure as both a parallel and a competing distribution grid model at the micro scale. The adoption and integration of microgrids, therefore, represents a socio-technical transition in the electric power sector. In this context, this study relies on the Multi-Level Perspective framework to examine the drivers, contexts, processes, and policies that have enabled an ongoing transition in California's electricity system that has allowed adoption of microgrids. The analysis shows that even though several drivers carry weight, including resilience concerns and market factors, California's pathway to microgrids is largely driven by the legislative and regulatory push toward clean energy and a symbiotic relationship between powerful regime actors and a microgrid niche. This is enabling a transformation in the state's energy system, in which the entry of microgrids is subtly facilitated by the regime in a way that does not threaten the current utility-dominated electricity system. By providing a detailed account of how a decentralized energy system that challenges the centralized grid regime has made its place in the centralized grid regime in California, this paper identifies the key facets that affect the integration of microgrids in the broader context of energy transitions. • A Multi-Level Perspective analysis of microgrid adoption in California is presented. • Legislative and regulatory push toward clean energy is driving this transition. • Microgrids are being nurtured by a symbiotic relationship between regime and niche. • The study shows that symbiotic niche-regime relationship is key in energy transitions. [ABSTRACT FROM AUTHOR]

Integrated Energy Systems (IES) become more and more important for the sustainability in energy system development and for promoting the application of clean energy technologies. System complexity and various uncertainties interaction make it difficult to maintain a reliable energy supply. In this paper, a systematic method is proposed for energy supply reliability analysis in complex Integrated Energy Systems (IES). The developed method integrates stochastic modeling, supply capacity analysis and reliability evaluation, which is able to give more comprehensive knowledge of the ability of the IES for satisfying the energy needs under different, coupled uncertainties. Firstly, stochastic models are developed for each unit in IES, including renewable energy, customer demands and components in natural gas pipeline networks and electric power grids, according to their characteristics. Then, a two-stage optimization model is developed for simulating the operation strategies of IESs, and calculating the supply capacities under randomly generated scenarios. Finally, the reliability of supply is evaluated based on the results of the random simulations. The developed method is used to analyze the supply reliability of an assumed IES, to test its effectiveness. The results show the ability to provide valuable information from multiple perspectives including system, individual customer and resource allocation, for design, extension and management of IES. • A systematic method is developed for reliability of energy supply in IES. • Different uncertainties can be coupled and analyzed in the proposed method. • The complexities of system structure and dynamics are modeled in this framework. • Supply reliability is analyzed from the aspects of system, customers and resources. [ABSTRACT FROM AUTHOR]

• Based on the requirement of integrated transportation of electricity and LNG, an effective structure with high safety and efficient heat exchange is proposed. • The HTS tape and insulation medium used in LNG temperature range are discussed. • Based on the comparison of different types of bipolar cable and pipeline, the overall design scheme of ±100 kV/1 kA superconducting DC energy pipeline with optimized comprehensive performance is given. High Tc Superconducting (HTS) DC cable is a promising solution for large-scale power transmission over long distance. However, the indispensable refrigeration system for HTS cable might be undesirable. Considering that LNG (liquid natural gas) now is one kind of clean energy that is used more widely and widely, it is possible to integrate the HTS cable and LNG transportation into an energy pipeline, resulting an acceptable new energy transportation system. In this paper, the principle and structure of the energy pipeline are discussed firstly, and then the basic physical properties of HTS tapes and liquid insulation media in LNG temperature range are analyzed. On the base as above, the general design of ±100 kV/1kA energy pipeline is made. [ABSTRACT FROM AUTHOR]

During the last decades, renewable energy production has significantly increased in an effort to produce clean energy that will not affect the environment. Governments around the world are focusing on reducing greenhouse gas emissions by increasing the utilization of renewable energy sources in the power chain. Wind farms and wind generators are the main renewable technology that are used worldwide. The main scope of wind farm designers is the achievement of the maximum possible power, restraining the installation cost that is related to the use of a specific number of wind turbines for specific power production, and considering the area of land to be occupied. A harmony search method is presented in this paper for the determination of the optimum number of wind turbines in a wind farm and the total electric power produced. The method is applied for comparison purposes on data from previously published methodologies proving its accuracy and effectiveness. The harmony research method can be used in the studies of wind farm designers aiming to reduce installation costs. [ABSTRACT FROM AUTHOR]