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The large‐scale penetration of electric vehicles (EVs) into the power system will provoke new challenges needed to be handled by distribution system operators (DSOs). Demand response (DR) strategies play a key role in facilitating the integration of each new asset into the power system. With the aid of the smart grid paradigm, a day‐ahead charging operation of large‐scale penetration of EVs in different regions that include different aggregators and various EV parking lots (EVPLs) is propounded in this study. Moreover, the uncertainty of the related EV owners, such as the initial state‐of‐energy and the arrival time to the related EVPL, is taken into account. The stochasticity of PV generation is also investigated by using a scenario‐based approach related to daily solar irradiation data. Last but not least, the operational flexibility is also taken into consideration by implementing peak load limitation (PLL) based DR strategies from the DSO point of view. To reveal the effectiveness of the devised scheduling model, it is performed under various case studies that have different levels of PLL, and for the cases with and without PV generation.

Decarbonisation, energy security and expanding energy access are the main driving forces behind the worldwide increasing attention in renewable energy. This paper focuses on the solar photovoltaic (PV) technology because, currently, it has the most attention in the energy sector due to the sharp drop in the solar PV system cost, which was one of the main barriers of PV large-scale deployment. Firstly, this paper extensively reviews the technical challenges, potential technical solutions and the research carried out in integrating high shares of small-scale PV systems into the distribution network of the grid in order to give a clearer picture of the impact since most of the PV systems installations were at small scales and connected into the distribution network. The paper reviews the localised technical challenges, grid stability challenges and technical solutions on integrating large-scale PV systems into the transmission network of the grid. In addition, the current practices for managing the variability of large-scale PV systems by the grid operators are discussed. Finally, this paper concludes by summarising the critical technical aspects facing the integration of the PV system depending on their size into the grid, in which it provides a strong point of reference and a useful framework for the researchers planning to exploit this field further on.

Intelligent Transportation Systems (ITSs) utilize Vehicular Ad-hoc Networks (VANETs) to collect, disseminate, and share data with the Traffic Management Center (TMC) and different actuators. Consequently, packet drop and delay in VANETs can significantly impact ITS performance. Feedback-based eco-routing (FB-ECO) is a promising ITS technology, which is expected to reduce vehicle fuel/energy consumption and pollutant emissions by routing drivers through the most environmentally friendly routes. To compute these routes, the FB-ECO utilizes VANET communication to update link costs in real-time, based on the experiences of other vehicles in the system. In this paper, we study the impact of vehicular communication on FB-ECO navigation performance in a large-scale real network with realistic calibrated traffic demand data. We conduct this study at different market penetration rates and different congestion levels. We start by conducting a sensitivity analysis of the market penetration rate on the FB-ECO system performance, and its network-wide impacts considering ideal communication. Subsequently, we study the impact of the communication network on system performance for different market penetration levels, considering the communication system. The results demonstrate that, for market penetration levels less than 30%, the eco-routing system performs adequately in both the ideal and realistic communication scenarios. It also shows that, for realistic communication, increasing the market penetration rate results in a network-wide degradation of the system performance.

Replacing conventional fossil fuel power plants with large-scale renewable energy sources (RES) is a crucial aspect of the decarbonization of the power sector and represents a key part of the carbon-neutral strategy of China. The high penetration rate of renewable energy in the electricity system, however, implies the challenges of dealing with the intermittency and fluctuation of RES. Power to gas (P2G), which can convert surplus renewable power into a chemical form of energy (i.e., synthetic gas), can help handle this challenge and supply new energy carriers for various energy sectors. By modeling three potential 2060 energy mix scenarios in China, this paper aims to describe the possible contribution of the high penetration rate of renewable energy combined with P2G in the future sustainable energy system. Different schemes are listed and compared, and the results are used in a basic economic evaluation of the synthetic gas production cost for the P2G plants. Ideally, nearly 18 million tons of carbon dioxide would be recycled and transformed into methane (around 9.37 km 3 ) annually in China. Considering a zero price for the excess renewable power and future costs of the components, the levelized cost of energy (LCOE) of the final production of methane is estimated at 0.86 $/m 3 SNG .

Transmission line conventional current differential schemes are significantly impacted by the dynamic fault current features, transient behavior, and unpredictable power generation of large-scale doubly fed induction generator-based wind farms (DFIG-WFs). Further, combined effects of WFs and flexible alternating current transmission system (FACTS) controller have adverse effect on various unit protection schemes. Normal transmission lines have a current differential between the two ends that rises with line length. If the WFs power output is low, the capacitive charging current may match the load current. Conventional differential protection methods are facing difficulties in the presence of WFs. This research proposes a data-driven approach to determine the effects of several scenarios with significant offshore WFs coupled to transmission lines on differential relay characteristics. The per-phase differential current is calculated using the short-term matrix pencil method (STMPM) based signal reconstruction technique. The net change in the current magnitude is then determined by estimating the first- and second-order derivatives of this data. Lastly, a disturbance detection index (DDI) is derived from the Euclidean distance between these first and second derivative components. The PSCAD/EMTDC simulation studies that were carried out show that the suggested strategy functions satisfactorily for a variety of disturbances, such as internal and external faults, fault resistance, fluctuating fault position, WF penetration changes, and other types of non-fault switching events.

While recycling is a topic of contemporary relevance, there is a scarcity of research on the engineering characteristics of construction and demolition wastes with different levels of grain strength and composition of debris, which impose constraints on their potential for reuse. This study aims to increase the use of recycled aggregates in fillings, addressing a gap in the literature. For this purpose, large-scale direct shear and California bearing ratio tests were conducted on nine diverse recycled aggregates from different construction works. The test outcomes were compared to those obtained from natural aggregates (NA) to draw a meaningful conclusion. The impact of the specimens' water content and relative density on the findings was discussed. Results demonstrated that the shear strength of recycled aggregates is significantly affected by the compressive strength of the concrete within the recycled aggregates. Besides, increasing the percentage of NA or relative density improved the specimen's shear strength. On the other hand, it was determined that the high water content of the crushed bricks reduced the fill's quality. As a result of the study, equations were suggested for use in filling design.

The influence of sea-level rise (SLR) on seawater intrusion (SWI) has been the subject of several publications, which consider collectively a range of functional relationships within various hydrogeological and SLR settings. Most of the recent generalized analyses of SWI under SLR neglect land-surface inundation (LSI) by seawater. A simple analytical method is applied to quantitatively assess the influence and importance of LSI on SLR–SWI problems under idealized conditions. The results demonstrate that LSI induces significantly more extensive SWI, with inland penetration up to an order of magnitude larger in the worst case, compared to the effects of pressure changes at the shoreline in unconfined coastal aquifers with realistic parameters. The study also outlines some of the remaining research challenges in related areas, concluding that LSI impacts are among other important research questions regarding the SLR–SWI problems that have not been addressed, including the effects of aquifer heterogeneities, real-world three dimensionality, and mitigation measures.

The Sulawesi earthquake with a moment magnitude of Mw 7.5 struck the Central Sulawesi region of the Sulawesi Island, Indonesia, on September 28, 2018. The epicenter of the earthquake was located in the mountainous region of Donggala Regency, in the neck of the Minahasa Peninsula in the Central Sulawesi Province of Indonesia. Although the epicenter was located in Donggala Regency, the greatest devastating effects were observed about 70 km south of the epicenter in the Palu Valley. The event was the first of its kind to cause large-scale flowslides simultaneously at four key locations such as Balaroa, Petobo, Jono Oge, and Sibalaya with extensive ground displacements ranging from several hundred meters to more than 1 km. This article reviews the field observations of geotechnical failures and infrastructure damage caused by liquefaction resulting from the shallow strike-slip earthquake at Palu City, Donggala Regency, and Sigi Regency. A geo-spatial analysis was performed on data collected from aerial drone imagery, along with portable dynamic cone penetration testing (PDCPT) in the field. The investigation revealed a highly stratified ground with alternating soil layers of varying permeability and very low bearing resistance at shallow depths. The investigation also helped in assessing the extent of damage caused by geotechnical failure to the residential infrastructures, irrigation structures, and roads.

The centralised utility‐scale photovoltaic (PV) plants installation has greatly enlarged their percentage in the bulk power systems, along with the nature uncertainty for the balance of system power and loads. Consequently, the successful integration of solar PV power in large‐scale power systems requires a reliable and efficient multi‐area automatic generation control (AGC) system within the control centre. Specifically, area‐AGCs that perform tie‐line bias control, in which the area frequency regulates the tie‐line power flow, must balance the operational control area supply power‐and‐demand loads within a pre‐tuned parameter set. Traditional AGC control systems have area linear controllers that must be periodically tuned to manage the high fluctuation of PV power. A practical two‐step tuning method to determine the optimal parameters of existing multi‐area AGCs is presented. The proposed method is demonstrated on a five‐area multi‐machine power system with two large PV plants. The power system was equipped with the synchrophasor‐based monitoring system, with a real‐time simulation platform serving as the application host. Results indicated that the two‐step tuning method provides optimal parameters for all the system AGCs over a wide range of PV penetration levels. Typical results demonstrated the effectiveness of the tuned multi‐area AGCs under dynamic conditions and disturbances.

Converter-based generators (CBGs) that use renewable energy sources (RESs) are replacing traditional aging coal and nuclear power generators. Increasing the penetration of CBGs into the entire power generation process reduces both the inertia constant of the power system and the total amount of power reserves. Additionally, RESs are very intermittent and it is difficult to predict changes in them. These problems, due to CBGs using RESs, pose new challenges to net–load balancing. As a solution, this paper proposes a virtual multi-slack (VMS) droop control that secures the stability and efficiency of system operation by controlling the output of CBGs distributed in various regions. The VMS droop control makes it possible to increase the inertia constant of the power system and to respond quickly and appropriately to load changes through the proposed VMS droop control based on power sensitivity. It is also proposed that the process selects proper power reserves of CBGs for stable VMS droop control. To verify the effectiveness of the proposed VMS droop control and the proper power reserve selection method for CBGs, several case studies were performed using a real Korean power system.