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We constructed a capacitive bioanode PPy/EABs@Mag-CLF/SA for circumventing the bioelectrochemical reaction shift during voltage reversal of series-stacked MFC. Sodium alginate hydrogel (SA) was made as the binder, in which the conducting polymer polypyrrole (PPy) was doped. Biomagnetic carbonized loofah particles (EABs@Mag-CLF) cultured in a pulsating fluidized bed were encapsulated by hydrogel as the anode biocatalyst. The pseudocapacitive material PPy combined with the biofilm capacitance attached to 3D biochar particles together constructed the biocapacitor anode with an energy storage function. The result showed that the power density of PPy100/EABs@Mag-CLF100/SA (71.88 W/m3) was 1.87 times more than PPy100/EABs@Mag-CLF50/SA. In the charge/discharge test (C60/D60), the stored charge Q s of PPy100/EABs@Mag-CLF100/SA (460.97 C/m2) was 3.74 times greater than that of PPy20/EABs@Mag-CLF100/SA. Stacked MFCs equipped with PPy100/EABs@Mag-CLF100/SA anodes had a smaller threshold resistance (R threshold) and recovered their performance even after a voltage reversal. This can provide an ideal energy solution for intermittently operating microelectronic devices. [Display omitted] • The bio-loading step was added to the anode preparation process. • Intermittent pulsating fluidized beds were used to culture EABs@Mag-CLF. • Hydrogel capacitive bioanodes were used to buffer voltage reversal. • The charge/discharge capability of MFC was enhanced by PPy/EABs@Mag-CLF/SA. • Traditional 3D structures were replaced by carbonized N-doped biochar particles. [ABSTRACT FROM AUTHOR]

An interdisciplinary research project supported by the European Regional Development Fund focuses on developing energy infrastructure projects. These projects aim not only to enhance energy security but also to provide predictable ecosystem services related to high and low water protection, as well as drinking water production. The background of the project is the Lower Saxony region of the Upper Harz Mountains in Northern Germany, which in recent years has been characterised by severe flood events but also by previously unknown periods of low water and bottlenecks in the drinking water supply. At the same time, the existing dams and the underground infrastructure from former mining offer potential for the development of pumped storage capacities that could be used to stabilise the grid or to produce green hydrogen for the adjacent industrial regions. Given the target system: (1) Water quantity management (flood protection and low water elevation), (2) Drinking water production, (3) Energy storage and electricity generation, this paper describes how project alternatives are generated under the geological conditions of a low mountain range and its foothills. The target system for evaluating infrastructure alternatives at different locations should also include construction costs (4) and the associated consumption of natural resources (5), such as in the area of flora and fauna. Moreover, it analyses how these alternatives can be evaluated in the course of a collective decision-making process. Since the benefits arising are multi-dimensional and cannot simply be quantified and offset against one another using market data and net present value estimates, the decision-making process of the Analytical Hierarchy Process is used for the evaluation. Here, the structure of a given target system is used to evaluate a set of sufficiently defined and independent alternatives. The advantage of this procedure is that the weighting of the single target dimensions does not have to be determined exogenously but is carried out in the process of collective decision-making. Decision-makers are asked to make pairwise comparisons within the respective target dimension. A ranking of the alternatives can be determined from the combination of the previously recorded target weights and the evaluations of the alternatives within the respective target dimension. The knowledge gained in the project can be used very well for future real investment projects for several reasons. First, the weighting of the target structure can be made transparent with this method. It can be shown, for example, how the ranking of the alternatives changes when the weightings are changed. Secondly, due to its participatory aspects, this procedure can be used for communication, for example, in the course of citizen participation procedures. [ABSTRACT FROM AUTHOR]

It is a great desire of advanced designed materials for electricity generation, storage, and utilization with boosted activity, multifunctionality, compatibility, stability, and durability. Organic ionic materials (OIMs) with superior conductivity, modifiability, and thermal/cold tolerance have great potential in meeting the demand. Ionic liquids, ionic polymers, polyelectrolytes, and new‐emerging composite materials like ionic gels, ionic woods, and metallated covalent organic frameworks have been boomingly developed in recent years, with elaborated design of which, enhanced performance of burgeoning energy materials such as higher electrical output, larger energy capacity, wider tolerance of temperature and/or humidity, and longer durability have been promoted. Despite a few reviews that have generalized the applications of single‐type OIMs in a certain field, there is a lack of comprehensive reviews focusing on advanced design of OIMs for boosting electricity generation, storage, and utilization. Herein, the new development of OIMs is timely and systematically reviewed focusing on electricity generation (generators), storage (batteries and supercapacitors), and utilization (sensors and actuators). Synthesis and modification strategies are summarized for material design, after which, fundamentals and mechanisms are illustrated as theoretical support. Then, advanced designs of OIMs are elaborated by taking electricity generation, storage, and utilization processes into consideration, followed by putting forward perspectives. [ABSTRACT FROM AUTHOR]

An interdisciplinary research project funded by the EU Regional Development Fund (ERDF) deals with the question of how energy infrastructure projects can be developed which, in addition to their contributions to security of energy supply, also provide plannable ecosystem services in the area of high and low water protection and drinking water production. The background of the project is the Lower Saxony region of the Upper Harz Mountains in Northern Germany, which in recent years has been characterized by severe flood events, but also by previously unknown periods of low water and bottlenecks in the drinking water supply. At the same time, the existing dams and the underground infrastructure from former mining offer potential for the development of pumped storage capacities that could be used to stabilize the grid or to produce green hydrogen for the adjacent industrial regions. Given the target system Water quantity management (flood protection and low water elevation) (1), Drinking water production (2), Energy storage and electricity generation (3) this paper describes how project alternatives are generated under the geological conditions of a low mountain range and its foothills. The target system for evaluating infrastructure alternatives at different locations should also include construction costs (4) and the associated consumption of natural resources (5), such as in the area of flora and fauna. Moreover, it analyses, how these alternatives can be evaluated in the course of a collective decision-making process. Since the benefits arising are multidimensional and cannot simply be quantified and offset against one another using market data and NPV-estimates, the decision-making process of the Analytical Hierarchy Process (AHP) is used for the evaluation. The knowledge gained in the project can be used very well for future real investment projects for several reasons. First, the weighting of the target structure can be made transparent with this method. It can be shown, for example, how the ranking of the alternatives changes when the weightings are changed. Secondly, due to its participatory aspects, this procedure can be used for communication, for example in the course of citizen participation procedures.

Copyright of Energy Policy Journal / Polityka Energetyczna is the property of Mineral & Energy Economy Research Institute of the Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As the adoption of distributed energy resources (DERs) grows, the future of electricity distribution systems is confronted with significant challenges. These challenges arise from the transformation of consumers into prosumers and the resulting increased system complexity, leading to more pressure on the distribution grids. To address this complexity, a Digital Twin framework is designed to simulate DERs within distribution grids effectively. This framework is structured around four key modules: DERs, the electricity distribution grid, the energy management system, and the consumers. It incorporates a communication interface to facilitate interactions among these modules and includes considerations for grid topologies and demand-side configurations. The framework allows for the exploration of various DER adoption rates and capacities. The validation of this framework involves case studies on two Danish distribution grids with scenarios incorporating rooftop photovoltaic (PV) systems, batteries, and electric vehicles, considering different combinations of these technologies. The findings demonstrate the framework's ability to depict the states of the grid, PV systems, electric vehicles, and battery systems with a 10 min resolution over periods ranging from a day to over a decade. [ABSTRACT FROM AUTHOR]

Featured Application: The described methodology can be utilized to simulate and optimize microgrids with similar or desired designs, with the objective of assessing the logistical and environmental performance indicators of their operations. European islands have been leading the charge in renewable energy innovation. Yet, the intermittent nature of sources like solar and wind poses challenges such as grid saturation and frequency variations. Limited interconnection with mainland grids exacerbates these issues, necessitating backup from conventional power sources during low-production periods. Until 2021, Crete operated independently, but new infrastructure now integrates it with the Greek mainland grid, facilitating swift energy transfers. This integration enables surplus power from Crete's solar and wind systems to be transmitted to the mainland and vice versa. However, reliance on remote power production exposes the island to market fluctuations and distant disruptions, impacting electricity production. Storage technologies offer a solution, enhancing renewable energy penetration while reducing carbon emissions. Green hydrogen, a rising storage method, shows promise in offsetting carbon emissions. Its clean-burning nature minimizes environmental impact and reduces reliance on costly and harmful conventional sources. This study aims to evaluate the feasibility of achieving carbon-neutral electricity production in Crete, Greece, using hydrogen storage to offset annual carbon emissions in a financially viable and sustainable manner. Hydrogen's clean-burning properties reduce environmental impact and lessen dependence on expensive and environmentally harmful conventional sources. The methodology prioritizes the independence of the Cretan electricity system, utilizing electrolysis to produce green hydrogen and proton-exchange membrane (PEM) fuel cells for energy generation. It investigates the optimal expansion of renewable energy systems, including photovoltaic (PV) and wind turbine (WT) parks, alongside the installation of hydrogen storage, under specific assumptions. This proposed installation aims to achieve both island independence and profitability, requiring an additional expansion in PV capacity of 2.13 GW, WT capacity of 3.55 GW, and a hydrogen system with electrolyzer and fuel cell capacities totaling 278.83 MW each, along with a hydrogen tank capacity of 69.20 MWh. The investment entails a capital expenditure (CAPEX) of 6,516,043,003.31 EUR for a nearly zero net present value (NPV) over 20 years. However, carbon neutrality cannot be attained through this optimal solution alone, as relying solely on carbon sequestration from olive groves, the primary crop cultivated on the island, is insufficient as a carbon sink method. The annual net carbon emissions from electricity production, island transport, residential heating, and carbon sequestration are estimated at 94,772.22 tCO2. [ABSTRACT FROM AUTHOR]

Power sector and energy systems models are widely used to explore the impacts of demographic, socio-economic or policy changes on the cost and emissions of electricity generation. Technology cost and performance data are essential inputs to such models. Despite the ubiquity and importance of these parameters, there is no standardised database which collates the variety of values from across the literature, so modellers must collect them independently each time they populate or update model inputs, leading to duplicated efforts and inconsistencies which can profoundly influence model results. Technology cost and performance varies between countries, regions and over time, meaning that data must be country- or region-specific and frequently updated. Values also vary widely between sources, so obtaining a broad consensus view is critical. Here, we present a database which collates historical, current, and future cost and performance data and assumptions for the six most prominent electricity generation technologies; coal, gas, hydroelectric, nuclear, solar photovoltaic (PV) and wind power, which together accounted for over 92 % of installed generation capacity in 2022. In addition, we provide the same data for utility-scale battery energy storage systems (BESS), regarded as critical to the integration of variable renewables such as wind and solar PV. The data are global in scope but with regional and national specificity, covers the years 2015 through to 2050, and span 5518 datapoints from 56 sources. The database enables modellers to select and justify model input data and provides a benchmark for comparing assumptions and projections to other sources across the literature to validate model inputs and outputs. It is designed to be easily updated with new sources of data, ensuring its utility, comprehensiveness, and broad applicability in future.

The problem of determining the optimal parameters of electric energy storage and generating sources in autonomous local power systems is presented. A detailed justification of the role of electricity storage in the presence of renewable energy sources in autonomous local power systems with a stochastic mode of operation is given. The main provisions of the used model of autonomous local electrical systems are given. The dependence of the electricity storage parameters depending on the composition of the generation was investigated. The possibility of solving the problem of determining the parameters of electricity storage devices by simulating the operation of a real system is considered. The results of the multi-criteria selection of the power and energy capacity of the electricity storage unit using economic criteria are determined. A mathematical model for determining the optimal parameters of electric energy storage for autonomous local electrical systems using mixed integer programming with optimization based on economic indicators has been developed. The dependence of the parameters of electric energy storage devices on the composition of the generation of autonomous local electrical systems has been studied. Bibl. 7, fig. 2.

European islands have been leading the charge in renewable energy innovation. Yet, the intermittent nature of sources like solar and wind poses challenges such as grid saturation and frequency variations. Limited interconnection with mainland grids exacerbates these issues, necessitating backup from conventional power sources during low-production periods. Until 2021, Crete operated independently, but new infrastructure now integrates it with the Greek mainland grid, facilitating swift energy transfers. This integration enables surplus power from Crete’s solar and wind systems to be transmitted to the mainland and vice versa. However, reliance on remote power production exposes the island to market fluctuations and distant disruptions, impacting electricity production. Storage technologies offer a solution, enhancing renewable energy penetration while reducing carbon emissions. Green hydrogen, a rising storage method, shows promise in offsetting carbon emissions. Its clean-burning nature minimizes environmental impact and reduces reliance on costly and harmful conventional sources. This study aims to evaluate the feasibility of achieving carbon-neutral electricity production in Crete, Greece, using hydrogen storage to offset annual carbon emissions in a financially viable and sustainable manner. Hydrogen’s clean-burning properties reduce environmental impact and lessen dependence on expensive and environmentally harmful conventional sources. The methodology prioritizes the independence of the Cretan electricity system, utilizing electrolysis to produce green hydrogen and proton-exchange membrane (PEM) fuel cells for energy generation. It investigates the optimal expansion of renewable energy systems, including photovoltaic (PV) and wind turbine (WT) parks, alongside the installation of hydrogen storage, under specific assumptions. This proposed installation aims to achieve both island independence and profitability, requiring an additional expansion in PV capacity of 2.13 GW, WT capacity of 3.55 GW, and a hydrogen system with electrolyzer and fuel cell capacities totaling 278.83 MW each, along with a hydrogen tank capacity of 69.20 MWh. The investment entails a capital expenditure (CAPEX) of 6,516,043,003.31 EUR for a nearly zero net present value (NPV) over 20 years. However, carbon neutrality cannot be attained through this optimal solution alone, as relying solely on carbon sequestration from olive groves, the primary crop cultivated on the island, is insufficient as a carbon sink method. The annual net carbon emissions from electricity production, island transport, residential heating, and carbon sequestration are estimated at 94,772.22 tCO2.

Research on large-scale energy storage systems has so far been very dedicatedly focused on electricity storage. Even for thermal energy-driven technologies, so-called Carnot batteries, larger electricity output, and higher power-to-power efficiency have been the major concerns. On the other hand, energy storage technologies are mainly useful for helping more renewable energy deployment for which recent studies show that most of the energy sectors are going through a smooth and continuous transition towards sustainability except for the industrial heating and cooling sectors. Therefore, developing energy storage solutions that can potentially contribute to this sector will be precious. This study proposes a multi-generating solar-assisted molten-salt-driven Carnot battery that is used for storing excess electricity of a PV farm in Saudi Arabia and delivering power for grid balancing, steam for process heating, as well as space heating/cooling for several industrial factories. The article presents a detailed techno-economic analysis of the system after making the configuration optimized based on multi-objective optimization techniques. The results show that such a multi-generating solar-assisted molten-salt-driven Carnot battery in the optimized configuration may result in power-to-power, power-to-process heat, and overall efficiencies of 26.82%, 55.78%, and 82.6%. With these performance factors, using standard global prices for electricity and heating, with a process heating cost of higher than 10.15 c$/kWh (which is very realistic), the system will outperform only power-generating Carnot batteries. [ABSTRACT FROM AUTHOR]

The paper presents the types of batteries used to store electricity. The operating principle, advantages, disadvantages and areas of use are mentioned based on a study of the specialized literature. A comparison of the energy efficiency of different types of batteries is also presented, with end users able to make a choice knowing the cause. [ABSTRACT FROM AUTHOR]

Hydrodynamic cavitation (HC), which can effectively induce sonochemical effects, is widely considered a promising process intensification technology. In the present study, HC was successfully utilized to intensify the alkali activation of GPs for SCs, for the first time. Five BDCMs were synthesized following the method reported in the literature. For comparison, four more BDCMs with HC-treated, among which a sample was further doped with nitrogen during the HC treatment, were prepared. Then all the samples were compared from microscopical characteristics to electrochemical performance as SCs materials. The morphology study demonstrated that the HC treatment had created many defects and amorphous carbon structures on the GP-based BDCMs, with the highest SSA reaching 3272 m2/g (1:6-HCGP), which 32 folded that of the Raw carbon sample’s. The HC treatment also intensified the N-doping process. XRD and XPS results manifested that the N content had been increased and consequently changed the electronic structure of the carbon atoms, leading to the increase of specific capacitance (1:6-HCGP+N-based SC, 227 F/g at 10 A/g). The cycle performance proved that the GP-based BDCMs have long-term stability, indicating that the HC-treated BDCMs were good choices for energy storage technologies. Compared with the ultrasound-assisted method, which may have a high energy density, the HC-assisted method enables high production and energy efficiency. This work is a first time attempt towards the industrial application of HC method in energy-related materials synthesis and encourages more in-depth studies in the future.

Solar and wind power systems have been prime solutions to the challenges centered on reliable power supply, sustainability, and energy costs for several years. However, there are still various challenges in these renewable industries, especially regarding limited peak periods. Solar–wind hybrid technology introduced to mitigate these setbacks has significant drawbacks and suffers from low adoption rates in many geographies. Hence, it is essential to investigate the challenges faced with these technologies and analyze the viable solutions proposed. This work examined solar–wind hybrid plants' economic and technical opportunities and challenges. In the present work, the pressing challenges solar–wind hybrids face were detailed through extensive case studies, the case study of enabling policies in India, and overproduction in Germany. Presently, the principal challenges of solar–wind hybrids are overproduction, enabling policies, and electricity storage. This review highlights specific, viable, proposed solutions to these problems. As already recorded in the literature, it was discovered that academic research in this space focuses majorly on the techno-economic and seemingly theoretical aspects of these hybrid systems. In contrast, reports and publications from original equipment manufacturers (OEMs) and engineering, procurement, and construction engineers (EPCs) are more rounded, featuring real-life application and implementation. [ABSTRACT FROM AUTHOR]

Cuba's power supply is characterized by the dependence on imported oil, outdated power plants and frequent power curtailment. Cuba's government aims at changing this situation through the National Economic and Social Development Plan, which targets a renewable share of 37 % in 2030. In the longer term, the Cuban government has already acknowledged the goal of 100 % renewable electricity supply. This work reviews the current ambitions of the Cuban government and provides a scientific approach to identifying the most cost-effective 100 % renewable energy system in 2030. First, we study whether the generation mix proposed by the Cuban government to reach 37 % renewables is the most cost-effective. Second, we run a simulation that considers fossil and renewable energy technologies purely to optimize costs. Third, we investigate the renewable future for Cuba with a simulation under the constraint of a 100 % renewable energy share. Our results suggest that energy sector plans should be reconsidered from a techno-economic point of view: With the overall cost-optimization, we find that much higher renewable energy shares of over 80 % are possible at lower overall costs. Finally, we analyze that the cost viability of a 100 % renewable electricity depends largely on the ability to use Cuba's biomass resources to balance solar generation. • The Cuban expansion plan for 2030 can achieve the targeted 37 % RE with reduced LCOE. • A larger share of wind power capacities can reduce costs to achieve the 37 % target. • Optimization shows that higher RE shares of above 82 % are possible at lower costs. • The cost-optimal system is dominated by wind power and biomass power generation. • In the long term (reaching 100 % RE) a large solar PV capacity is required. [ABSTRACT FROM AUTHOR]

As the terminal of electricity consumption, the distribution network is a vital field to lower the carbon emission of the power system. With the integration of distributed energy resources, the flexibility of the distribution network has been promoted significantly where dispatch actions can be employed to lower carbon emissions without compromising the accessibility of reliable electricity. This study proposes a security constrained dispatch policy based on safe reinforcement learning for the distribution network. The researched problem is set up as a constrained Markov decision process, where continuous-discrete mixed action space and high-dimensional state space are in place. In addition, security-related rules are embedded into the problem formulation. To guarantee the generalization of the reinforcement learning agent, various scenarios are generated in the offline training stage, including randomness of renewables, scheduled maintenance, and different load profiles. A case study is performed on a modified version of the IEEE 33-bus system, and the numerical results verify the effectiveness of the proposed method in decarbonization.

In this paper, we investigate whether the interconnection of power grids with 100% renewable energy generation can bring greater economic benefits now that the technology exists for high power, long distance Ultra High Voltage Direct Current transmission. Based on multi-year historical weather data and demand series, this study compares eight interconnection schemes for three regional grids in Europe, North-East Asia, and North America where there is around 8-hour time difference between any of the two regions. Sensitivity analyses are presented with respect to infrastructure capital cost and different weather year which show that interconnection yields a reduction of approximately 18% in the total annual system cost. The results in this paper also indicate that the regional levelized cost of electricity (LCOE) drops by 31%, 10%, and 10% for Europe, North-East Asia and North America, respectively. It is concluded that there is a strong incentive through both annual cost saving and regional LCOE drop in favour of full long-distance interconnections between the three regions in the context of the international drive towards a net-zero strategy.

Summary: The Government of Finland is targeting carbon neutrality by 2035. Increasing electrification emphasizes the need for significant emission reductions in power generation. As reduction in power generation emissions is partly realized by increase in intermittent energy sources, electricity storage may become an important part of a carbon neutral power system. This study investigates the behavior of electrical storages as a part of a large‐scale national carbon‐free power system model. As a case study, a three‐year model of a carbon‐free Finnish power system set in 2050 with the aim to identify various factors affecting electricity storage, and the results are compared with literature. The proposed case study features various scenarios with a national power system with very high amounts of renewables and a significant hydro capacity, while amount of combustion‐based energy production is minimal. In addition, hydrological stress scenarios representing historically severe drought years were introduced. The amount of electricity storage needed was found to be most affected by nuclear and electricity trading capacities, which is consistent with literature findings. The data period used as basis for modeling also affected the need for electricity storage, as interannual variations in renewable production were found to have a large effect on modeled results. The needed electricity storage capacities increased significantly in the stress scenarios. The electricity storage need was found to be seasonal in nature, but this may be partly due to missing demand flexibility within the modeled power system, which caused very large individual storage discharge peaks. The results emphasize the need to take several years of historical data into account to ensure system availability in different conditions. Highlights: Nuclear energy was found to decrease system costs in a 100% carbon‐free power system.Multi‐year modeling is essential to secure system availability due to the important role of hydropower and seasonal wind variability.Electricity storages were found to be seasonal in nature. The main reason was exceptionally low windiness during individual periods, which resulted in large but temporarily short power deficits due to insufficient flexibility obtained from hydropower and power imports. This was especially evident in stress scenarios and mainly contributed to the higher costs in low‐nuclear scenarios.Detailed hydropower modelling of historically exceptional dry seasons in Finland was utilized as one stress scenario. Exceptionally, dry long‐term period increased the need for electricity storages significantly due to the lost flexibility offered by hydro and reduced electricity import capacities. [ABSTRACT FROM AUTHOR]

The present paper deals with the problem of building up a 100 MW hydro pumped storage power plant (PSHPP) in the Republic of Moldova allowing to integrate a larger capacity of renewables. The main technical characteristics of the plant have been determined (quantity of water to be pumped, the upper and the lower reservoir dimensions, etc.). Several possible plant locations were investigated and finally an indicative assessment of the plant economic feasibility has been carried out. The study demonstrates that on the territory of the Republic of Moldova exist the possibility to build a PSHPP, as a commercially proven technology for large-scale electricity storage. Building these types of plants is essential in the context of increasing variable renewable energy sources capacities, which requires the installation of new balancing capacities of the system. Abstract. The present paper deals with the problem of building up a 100 MW hydro pumped storage power plant (PSHPP) able to integrate a larger capacity of renewables. The main technical characteristics of the plant have been determined (quantity of water to be pumped, the upper and the lower reservoir dimensions, etc.). Several possible plant locations were investigated and finally an indicative assessment of the economic feasibility has been carried out. In order to determine the altitude of the slopes near the river were used the possibilities of the „Google Earth” software. The study demonstrates that on the territory of the Republic of Moldova there exists the possibility to build a PSHPP, as a commercially proven technology for large-scale electricity storage. Building these types of plants is essential in the context of increasing variable renewable energy sources capacities, which requires the installation of new balancing capacities of the system. By 2050, the country's power system requires capacities for balancing the intermittent production. Hydro pumped storage power plants become necessary in the generation capacity mix for all considered long-term development scenarios after 2030. The building of PSHPP, as the main largescale energy storage infrastructure, presents an important measure to increase the flexibility of the power system. Thus, the study demonstrates the attractiveness of implementing PSHPP projects.

The considered characteristics of the Northern sea route (NSR), nuclear icebreakers and theirship power engineering show expediency of power supply of coastal consumers with use of ship reactor devices (RU) of type of nuclear power plants of small power (ASMM) that allows to unify and replicate power installations. For the Arctic and the NSR, the use of ASMM, supplemented by a DC bus and the presence of storage devices is an alternative solution in terms of autonomy, reducing the emission of carbon dioxide and nitrogen, lack of maintenance and remote digital control. The alternative options of energy supply stationary and mobile installations of ground, surface, and submarine-based liquefied natural gas (LNG) include the use of aviation gas turbines up to 5 MW, and for sea-based vehicular gas turbines of 30 MW using energy storage devices, the capacity of which depends on the peak power of the consumers. The structure and composition of a mobile modular life support complex (MMCF) as part of an underwater or surface power module with a controlled rectifier, the output of which is connected by a bipolar underwater DC cable to the shore conversion, accumulation and distribution modules, are presented. The outputs of the latter are connected by ground bipolar cables to the inputs of the water and air treatment modules, as well as production and auxiliary modules. The complex with voltage from 1 to 10 kV with power from 1 to 10 MW is created using current and voltage converters, energy storage, switches and DC cables, equipped with digital control devices.the possibility of terminating the transit of reactive power with sufficiently intense geomagnetic disturbances.

Many studies have demonstrated the feasibility of fully renewable power systems. Yet the future costs of key technologies are highly uncertain, and little is known about the robustness of a renewable power system to these uncertainties. To analyze it, we build 315 cost scenarios by varying the costs of key technologies and we model the optimal renewable power system for France, simultaneously optimizing investment and dispatch. We add to the literature by studying a consecutive 18-years weather period; by testing all combinations of technology costs rather than changing them one-at-a-time; and by calculating the regret from optimizing the energy mix on the basis of cost assumptions that do not materialize. Our results indicate that the cost of a 100% system is not that sensitive to uncertainty. Admittedly, the optimal energy mix is highly sensitive to cost assumptions: across our scenarios, the installed capacity in PV, onshore wind and power-togas varies by a factor of 5, batteries and offshore wind even more. However, in every scenario the total production and storage cost is similar to, or lower than the current cost. This indicates that renewable technologies will become by and large substitutable. Moreover, even if the energy mix is optimized based on cost assumptions which turn out to be wrong, the extra cost is low: 4% in average and less than 9% in 95% of the scenarios. [ABSTRACT FROM AUTHOR]

The expanding use of electrical power generated from wind turbines and solar photovoltaic plants is enabled by the decreasing cost of electrical energy from sun and wind. With the advent of electrical energy from the intermittent solar and wind energy resources comes the requirement that electricity must be stored for use over time. The huge demand for materials for such storage systems will require a considerable energy input in extraction, processing and materials formulation, and new and sustainable electrochemical systems need to be developed. Storing electrical energy in bio based batteries is one of the options for handling the rapid expansion of renewable and variable electrical energy generated in wind turbines and in solar photovoltaic systems, from small to large. With projected needs for storage at 300 GWh for the coming decade, there are many niches for new technologies and possibilities. A supply line of materials for energy storage materials could be ultimately based on photosynthesis, in the form of materials derived from plants. Redox activity is possible in lignin, humic acid, and polyphenolic macromolecules, sometimes by electrochemical activation of redox groups. [ABSTRACT FROM AUTHOR]

Global efforts towards de-carbonization have opened the pathway for a test environment of electrical energy storage (EES) topology. In this work, the feasibility of 17 EES facilities applied to 24 individual applications of flexible power networks has been investigated in terms of levelized cost of storage (LCOS) in $/kW. Electricity storage facilities were modelled and evaluated via a life-cycle cost analysis, based on the most realistic EES characteristics and practical applications’ requirements. The results showed that pumped-hydro constitutes the least-cost and most reliable system for large-scale/long-duration applications. Zn-air and vanadium redox (VRB) offer great potential in demand-shifting and reactive support but, due to their wide LCOS range, considerable risk is added in such an investment. Electrochemical double-layer capacitor (EDLC) holds almost the exclusivity in fast-response/frequently-cycled applications, while for medium-term/medium-scale applications and where the large footprint is a prohibitive factor, valve-regulated Pb-acid (VRLA) and hydrogen fuel cells (H2-FC) are more favourable options. However, efficient tools still lack the ability of quantifying all benefits derived from electricity storage, maintaining stakeholders’ concerns for investment. It is apparent that, further research and development implies the decrease of the uncertainty governing the majority of EES technologies, increasing EES implementations and vice versa.

Copyright of EMERG: Energy. Environment. Efficiency. Resources. Globalization is the property of Romanian National Committee of World Energy Council and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A photovoltaic system could supply a single‐family house with electrical power, warm water, and room heat if the energy would be distributed over the year to suit the load profile. However, storage systems for this are not state of the art yet. A concrete example is used to estimate which parameters such a power storage system should have. A suitable electrochemical reaction system based on inorganic salt mixtures is proposed. The German Federal Ministry of Education and Research is currently funding the development of a world storage facility based on the same reaction system. [ABSTRACT FROM AUTHOR]

In this paper, we investigate whether and under which conditions jointly owning a variable renewable source of electricity (VRES) and an electricity storage generates economies of scope in competitive electricity markets. Using a simple stochastic optimization model that assumes frictionless markets, we analytically show that no economic benefit arises from combining the two assets. This finding is in contradiction to large parts of the literature, which claim that it is in the economic interest of owners of VRES to additionally own electricity storage. We also identify circumstances where our argument does not hold and the combination of storage and VRES could theoretically make economic sense on the level of individual agents. In the last part of the paper, we demonstrate in a numerical case study of the German market that even in cases where our theoretical results do not hold, tying together storage and VRES may produce suboptimal results. [ABSTRACT FROM AUTHOR]

The large-scale penetration of renewable energy, such as wind power, brings a lot of economic and environmental benefits to the grid, and it also causes hidden dangers in the reliability and security of the power system due to its uncertainty. As an effective demand-side management method, demand response has unique advantages in smoothing wind power fluctuations and mitigating grid pressure. This paper proposes a new model for the demand response aggregator (DRA) that includes both combined heat and power systems (CHPS) and energy storage devices. DRA can interact with the Independent system operator (ISO) through combined heat and power (CHP) units, energy storage devices, and the heat buffer tank to benefit from the electricity market and the thermal market simultaneously. At the same time, wind power producers (WPP) are modeled to turn wind power that was initially passively consumed into active market participants. The problem is modeled using an improved weighted method, which aims to take the diverse objectives of multiple market participants into account. The proposed model is tested on the modified IEEE RTS-24 test system to analyze the optimal scheduling strategies of each participant in the power market.

Nowadays, electric propulsion is one of the main fields of research (whether we are talking about the automotive field or the naval field). This paper presents the electric propulsion used on small boats (drones): the advantages of using electric propulsion, storage mode and possible methods of obtaining electricity (renewable sources of electricity). [ABSTRACT FROM AUTHOR]

Global warming plays an increasing role in our world, as the share of renewable energy sources in the overall production of electricity has witnessed exponential growth over the past years. Consumer demands are required to be met at any moment at a feasible price. However, storing energy in hot and arid climate regions is a sensitive matter as it is critical to consider appropriate technologies to implement for avoiding unnecessary causalities caused by extreme temperatures. This study compares 13 different energy storage methods, namely; pumped hydro, compressed air, flywheels, hot water storage, molten salt, hydrogen, ammonia, lithium‐ion battery, Zn‐air battery, redox flow battery, fuel cells, supercapacitors, and superconducting magnetic storage to be implemented in hot arid regions in terms of water usage, energy density, location dependency, and temperature degradation. A survey was conducted based on prior criteria to compare all 13 energy storage methods. The study concluded that the highest rankings for energy storage techniques are obtained for; Zn‐air battery, superconductors, and flywheels with overall rankings of 7.18, 6.73, and 6.61, respectively. In contrast, some of the rankings are very close to each other implying the potential application of several methods in hot climates. [ABSTRACT FROM AUTHOR]

We show how electricity storage is operated optimally when the load net of renewable output is uncertain. We estimate a diurnal Markov-process representation of how Germany's residual load changed from hour to hour and design a simple dynamic stochastic electricity system model with non-intermittent generation technologies and storage. We derive the optimal storage, generator output and capacity levels. If storage capacity replaces some generation capacity, the optimal storage strategy must balance arbitrage (between periods of high and low marginal cost) against precautionary storage to ensure energy is available throughout a long peak in net demand. Solving the model numerically under uncertainty (only the transition probabilities to future loads are known), we compare the results to perfect foresight findings. The latter over-estimate the cost-saving potential of energy storage by 27%, as storage can take up arbitrage opportunities that would not be chosen if there was a need for precautionary storage. [ABSTRACT FROM AUTHOR]

Hydrogen fuel cells being hydrogen energy storage devices are the most effective and environmentally friendly for energy accumulation and storage. Direct current provides the accumulation of electric energy and is therefore necessary when using renewable energy sources. The social and environmental aspects, as well as climatic and glaciological features of the Arctic development in terms of energy supply are considered. The most expedient ways of complex development of the Arctic are shown. In terms of large and unique stationary projects a number of shortcomings is marked. They are high cost and long-term construction, incomplete autonomy and insufficient solution of ecological and waste processing problems. Incomplete autonomy is due to the need for transportation of materials, products, replacement crews and personnel, as well as insufficient logistics and transportation difficulties on the mainland in summer and by sea in winter. Ecological and waste processing problems are associated with the use of traditional methods of burning solid and liquid fuel using coal or fuel oil, polluting the environment. Switching to the liquefied natural gas (LNG) for electric propulsion and power supply will significantly improve the environmental situation. The research performed on the mathematical model of the multifunctional energy complex (MEC) showed the possibility of uninterrupted power supply of local load from the centralized network, diesel generator (DG) and the electricity storage (ES); by that DG is used to save fuel as a backup source. The proposed technologies of power generation based on hydrogen or low-power nuclear power plants (LPNPPs) allow, along with improving the environment, to increase the energy efficiency of the direct fuel conversion plant and provide integrated waste processing. The small population of the Arctic, its mobility when using the rotational method require the integrated development of mobile energy and life support systems of low power up to 30 MW using LNG or LPNPPs, completed by renewable energy sources (RES). If the hydrogen installation is both a source and a storage of electricity, the use of LPNPPs and especially RES require energy storage devices. These hydrogen or electrochemical cycle storage devices are the most progressive in the world energy sector and their applicability significantly depends on the development of the service infrastructure. Typing and replication of power supply sources will solve the problem of development of remote and isolated regions of the Arctic through the integrated use of innovative technologies for generation, storage, transmission and distribution of electricity, life support, utilization and recycling of wastes, environmental conservation using hydrogen energy and digital control and monitoring systems. The climatic conditions of the Arctic and the presence of LNG determine the use of hydrogen as a source for generating electricity, heat, water and air. [ABSTRACT FROM AUTHOR]

Globally, around 1.1 billion people do not have access to electricity and 84% of the population who do not have modern energy access are living in rural and remote areas of developing countries. Since the loads are far from the grid and providing the connection by extending from the main grid requires a high investment associated with long and costly transmission and distribution lines, addressing the problem requires innovative solutions. Therefore, off-grid microgrid systems, using solar photovoltaic and storage systems, integrated with very high-efficiency lighting appliances, are a promising solution to supply energy for rural and remote location in areas which lack access to the electric grid. This paper presents an overview on the existing solar photovoltaic technologies for off-grid systems including the most recent plug and play solutions. A characterization of the most common strategies used for control, communication and metering of microgrids is presented, as well as the recent evolution of the associated component technologies. The security and protection systems used to protect the system against theft or robbery of the systems itself or energy theft in remote areas are also addressed. Additionally, a resumed characterization of the sociologic profile and motivation of people to damage off-grid systems is presented. An overview on the main off-grid appliance market evolution and efficiency trends, in terms of energy efficiency, is also addressed in this paper. Finally, a set of recommendations to promote cost-effective systems is made, considering the market evolution path and the large growth potential of off-grid systems. There is an urgent need to reduce the total system costs, namely the soft costs of new microgrid systems in order to further accelerate the market growth, as well as widely accepted open standards to regulate and develop the market. [ABSTRACT FROM AUTHOR]

Carnot batteries are a quickly developing group of technologies for medium and long duration electricity storage. It covers a large range of concepts which share processes of a conversion of power to heat, thermal energy storage (i.e., storing thermal exergy) and in times of need conversion of the heat back to (electric) power. Even though these systems were already proposed in the 19th century, it is only in the recent years that this field experiences a rapid development, which is associated mostly with the increasing penetration of intermittent cheap renewables in power grids and the requirement of electricity storage in unprecedented capacities. Compared to the more established storage options, such as pumped hydro and electrochemical batteries, the efficiency is generally much lower, but the low cost of thermal energy storage in large scale and long lifespans comparable with thermal power plants make this technology especially feasible for storing surpluses of cheap renewable electricity over typically dozens of hours and up to days. Within the increasingly extensive scientific research of the Carnot Battery technologies, commercial development plays the major role in technology implementation. This review addresses the gap between academia and industry in the mapping of the technologies under commercial development and puts them in the perspective of related scientific works. Technologies ranging from kW to hundreds of MW scale are at various levels of development. Some are still in the stage of concepts, whilst others are in the experimental and pilot operations, up to a few commercial installations. As a comprehensive technology review, this paper addresses the needs of both academics and industry practitioners.

Compressed air energy storage is an energy storage technology with strong potential to play a significant role in balancing energy on transmission networks, owing to its use of mature technologies and low cost per unit of storage capacity. Adiabatic compressed air energy storage (A-CAES) systems typically compress air from ambient temperature in the charge phase and expand the air back to ambient temperature in the discharge phase. This papers explores the use of an innovative operating scheme for an A-CAES system aimed at lowering the total cost of the system for a given exergy storage capacity. The configuration proposed considers preheating of the air before compression which increases the fraction of the total exergy that is stored in the form of high-grade heat in comparison to existing designs in which the main exergy storage medium is the compressed air itself. Storing a high fraction of the total exergy as heat allows reducing the capacity of costly pressure stores in the system and replacing it with cheaper thermal energy stores. Additionally, a configuration that integrates a system based on the aforementioned concept with solar thermal power or low-medium grade waste heat is introduced and thoroughly discussed.

In the background of the energy Internet, the number of data centres is increasing, aiming at the shortcomings of power supply and reliability in power supply system of traditional data centre and the development trend of green data centres. This article proposes an AC & DC hybrid power supply system with high-proportion renewable energy. The system includes photovoltaic generation, wind power generation, photothermal power generation, thermal utilisation system, power storage system, and different types of loads. Therein, a multi-port power electronic transformer is used to realise AC & DC multi-level mixing system with high proportion of variety of distributed renewable energy. Thereafter, the power supply, power grid, and the load can efficiently complement each other by using the integrated energy storage system such as electricity storage and heat storage. In detail, the rationality and functionality of the AC & DC hybrid power system are analysed through the system simulation and power supply reliability calculation. Moreover, the results show that the proposed hybrid power supply can effectively improve the impact of high-proportion renewable energy access to the grid and provide a new design scheme for the green data centre.

The common understanding of Power‐to‐X is exclusively the use of renewable electricity to manufacture products currently based on fossil sources. In this paper, it is argued that beyond such e‐Production many of these technologies also include aspects related to demand side management and temporal storage of electricity. Therefore, a definition of Power‐to‐X is suggested that encompasses all three aspects. It is discussed, which of these are relevant under which conditions and illustrative examples are highlighted, which show how process systems engineering can help address common challenges for Power‐to‐X technologies. [ABSTRACT FROM AUTHOR]

The storage of excess electricity from renewable energy sources is nowadays a crucial topic. One promising technology is the methanol (CH3OH) synthesis from H2/CO2 mixtures. The achievable one‐pass conversion is limited within this exothermic equilibrium reaction. A possibility to overcome this limitation would be withdrawing CH3OH and H2O from the gas phase through in situ condensation under reaction conditions. In this work, the phase equilibrium for mixtures representative for different degrees of conversion was studied. A view cell was employed to determine systematically the single‐ and two‐phase regimes and obtain phase envelopes for mixtures of H2, CO2, CH3OH, and H2O from 66 to 305 °C and 61 to 233 bar. Furthermore, the densities in the single‐phase area were determined and quantified by an empirical model. [ABSTRACT FROM AUTHOR]

Global efforts towards de-carbonization have opened the pathway for a test environment of electrical energy storage (EES) topology. In this work, the feasibility of 17 EES facilities applied to 24 individual applications of flexible power networks has been investigated in terms of levelized cost of storage (LCOS) in $/kW. Electricity storage facilities were modelled and evaluated via a life-cycle cost analysis, based on the most realistic EES characteristics and practical applications' requirements. The results showed that pumped-hydro constitutes the least-cost and most reliable system for large-scale/long-duration applications. Zn-air and vanadium redox (VRB) offer great potential in demand-shifting and reactive support but, due to their wide LCOS range, considerable risk is added in such an investment. Electrochemical double-layer capacitor (EDLC) holds almost the exclusivity in fast-response/frequently-cycled applications, while for medium-term/medium-scale applications and where the large footprint is a prohibitive factor, valve-regulated Pb-acid (VRLA) and hydrogen fuel cells (H2-FC) are more favourable options. However, efficient tools still lack the ability of quantifying all benefits derived from electricity storage, maintaining stakeholders' concerns for investment. It is apparent that, further research and development implies the decrease of the uncertainty governing the majority of EES technologies, increasing EES implementations and vice versa. [ABSTRACT FROM AUTHOR]

The conversion of the energy supply system towards renewable technologies is indispensable for climate and environmental protection. With the predominant use of inexhaustible but fluctuating renewable energy sources, energy storage capacities and physical networks are key infrastructure for sustainable functionality. Efficient pumped‐storage hydropower can meet these demands. However, suitable sites for conventional surface reservoirs are facing natural limits, and new storage capacities in ecologically sensitive mountainous valleys are increasingly difficult to license. To gap these aspects this article reflects the construction of fully underground pumped‐storage hydropower plants to cover multipurpose energy storage requirements. Thus, the surface reservoirs are substituted by underground storage caverns with less water volume required by equivalent energy storage capacity since high heads are utilized. Proximity to urban areas improves the construction and operation through various infrastructure and close connection to existing power grids, power plants and consumers. Valuable surface resources remain untouched and the closed water cycle ensures a constant storage volume and independent operation against external influences. Furthermore pumped‐storage is combined with seasonal underground thermal energy storage. This system leads the well‐proven hydraulic energy storage technology into a new energetic age and ensures the demand‐based and cross‐sectoral renewable energy supply. [ABSTRACT FROM AUTHOR]

Summary: Stationary batteries are projected to play a role in the electricity system of Switzerland after 2030. By enabling the integration of surplus production from intermittent renewables, energy storage units displace electricity production from different sources and potentially create environmental benefits. Nevertheless, batteries can also cause substantial environmental impacts during their manufacturing process and through the extraction of raw materials. A prospective consequential life cycle assessment (LCA) of lithium metal polymer and lithium‐ion stationary batteries is undertaken to quantify potential environmental benefits and drawbacks. Projections are integrated into the LCA model: Energy scenarios are used to obtain marginal electricity supply mixes, and projections about the battery performances and the recycling process are sourced from the literature. The roles of key parameters and methodological choices in the results are systematically investigated. The results demonstrate that the displacement of marginal electricity sources determines the environmental implications of using batteries. In the reference scenario representing current policy, the displaced electricity mix is dominated by natural gas combined cycle units. In this scenario, the use of batteries generates environmental benefits in 12 of the 16 impact categories assessed. Nevertheless, there is a significant reduction in achievable environmental benefits when batteries are integrated into the power supply system in a low‐carbon scenario because the marginal electricity production, displaced using batteries, already has a reduced environmental impact. The direct impacts of batteries mainly originate from upstream manufacturing processes, which consume electricity and mining activities related to the extraction of materials such as copper and bauxite. [ABSTRACT FROM AUTHOR]

In the background of the energy Internet, the number of data centres is increasing, aiming at the shortcomings of power supply and reliability in power supply system of traditional data centre and the development trend of green data centres. This article proposes an AC & DC hybrid power supply system with high-proportion renewable energy. The system includes photovoltaic generation, wind power generation, photothermal power generation, thermal utilisation system, power storage system, and different types of loads. Therein, a multi-port power electronic transformer is used to realise AC & DC multi-level mixing system with high proportion of variety of distributed renewable energy. Thereafter, the power supply, power grid, and the load can efficiently complement each other by using the integrated energy storage system such as electricity storage and heat storage. In detail, the rationality and functionality of the AC & DC hybrid power system are analysed through the system simulation and power supply reliability calculation. Moreover, the results show that the proposed hybrid power supply can effectively improve the impact of high-proportion renewable energy access to the grid and provide a new design scheme for the green data centre. [ABSTRACT FROM AUTHOR]

The need for innovative heating and cooling systems to decarbonize the building sector is widely recognized. It is especially important to increase the share of renewables at building level by maximizing self-consumption and reducing the primary energy demand. Accordingly, in the present paper, the results on a wide experimental campaign on a hybrid system are discussed. The system included a sorption module working as the topping cycle in a cascade configuration with a DC-driven vapor compression heat pump. A three-fluids heat exchanger with a phase change material (PCM), i.e., RT4 with nominal melting temperature of 4 °C, was installed on the evaporator side of the heat pump, for simultaneous operation as thermal storage and heat pumping purposes. The heat pump was connected to a DC-bus that included PV connection and electricity storage (batteries). Results showed that the energy efficiency of the heat pump in cascade operation was double compared to compression-only configuration and that, when simultaneously charging and discharging the latent storage in cascade configuration, no penalization in terms of efficiency compared to the compression-only configuration was measured. The self-sufficiency of the system was evaluated for three reference weeks in summer conditions of Athens climate and it was found that up to 100% of the electricity needed to drive the system could be self-produced for a modest cooling demand and up to 67% for the warmer conditions with high cooling demand.