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Abstract In order to fulfill the energy and power demand of battery electric vehicles, a hybrid battery system with a high-energy and a high-power battery pack can be implemented as the energy source. This paper explores a cloud-based multi-objective energy management strategy for the hybrid architecture with a deep deterministic policy gradient, which increases the electrical and thermal safety, and meanwhile minimizes the system’s energy loss and aging cost. In order to simulate the electro-thermal dynamics and aging behaviors of the batteries, models are built for both high-energy and high-power cells based on the characterization and aging tests. A cloud-based training approach is proposed for energy management with real-world vehicle data collected from various road conditions. Results show the improvement of electrical and thermal safety, as well as the reduction of energy loss and aging cost of the whole system with the proposed strategy based on the collected real-world driving data. Furthermore, processor-in-the-loop tests verify that the proposed strategy can achieve a much higher convergence rate and a better performance in terms of the minimization of both energy loss and aging cost compared with state-of-the-art learning-based strategies.

Abstract The combination of wind turbines with fuel cells (FC) and electrolyzers (ELY) is an option for balancing fluctuating grid power injections from renewable energy sources. The conversion of electricity to hydrogen via ELY is often called “power to gas”, while transforming hydrogen to electricity via FC is referred to as re-electrification. The application of these technologies currently faces high costs and finding a positive business case is challenging. This study quantifies the economic potential of marketing FC/ELY systems’ flexibility. Their potential to reduce wind farm forecast errors as well as the system’s ability to provide secondary control reserve (SCR) in Germany is investigated. For this purpose, data for the year 2013 is used. Different root mean squared errors and a probability density function (PDF) for forecast errors are considered. SCR dispatch power in high temporal resolution is approximated and different bidding strategies (SCR market) are taken into account. Results show that both applications can be economically viable, also when being combined. However, profitability is highly dependent on the system’s configuration as well as its operating strategy.

6. International Conference on Smart Energy Systems and Technologies, SEST 2023, Mugla, Turkey, 4 Sep 2023 - 6 Sep 2023; Sustainable energy, grids and networks 40, 101501 (2024). doi:10.1016/j.segan.2024.101501 special issue: "Special Issue: 6th International Conference on Smart Energy Systems and Technologies (SEST 2023) / Guest Editors: Dr. Gerardo J. Osório (Prince Henry Portucalense University, Porto,, Portugal); Assoc. Professor Akin Tascikaraoglu (Muğla Sıtkı Koçman University, Muğla,, Turkey); Dr. Andrea Mazza (Polytechnic of Turin Department of Energy, Torino,, Italy); Dr. Alper Ciçek (Trakya University, Edirne,, Turkey)" Published by Elsevier, Amsterdam [u.a.]

AbstractGrowing Nile tilapia in brackish water showed promising results, but the possibility of ammonia exposure can interrupt health status and productivity. Herein, the study tested the combined effects of water salinity and ammonia exposure on the antioxidative status, serum biochemistry, and immunity of Nile tilapia. Fish were assigned to eight groups where fish were reared in saline water (5, 10, and 15 ppt) with continuous or intermittent (every 3 days) total ammonia (TAN) exposure (5 mg TAN/L) (2 × 4 factorial design). After 30 days, the water salinity, TAN, and their interaction were markedly (P < 0.05), affecting the growth performance (final weight, weight gain, and specific growth rate) and survival rate of Nile tilapia. The growth performance and survival rate were markedly lower in tilapia grown in 15 ppt with continuous TAN exposure than in the remaining groups. The results showed that fish exposed to higher salinity levels (10 and 15 ppt) and continuous TAN exposure had a more robust antioxidative response, as evidenced by higher superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities and lower malondialdehyde (MDA) levels in the homogenates of the gills, intestines, and livers. The gills were notably affected, with congestion of primary filaments blood vessels and degeneration or shedding of secondary filaments epithelium, especially at salinity levels of 10 and 15 ppt. Additionally, the intestines displayed hyperplasia and inflammatory cell infiltration of intestinal mucosa at 5–10 ppt salinity, degeneration and sloughing of the intestinal epithelium at 15 ppt saline water, and increased goblet cell number at salinity of 10 ppt. The study found that continuous TAN exposure had a more significant impact on the fish, especially at higher salinity levels. Water salinity, TAN, and their interaction significantly affected all measured blood bio-indicators (total, albumin, globulin, ALT, AST, creatinine, urea, glucose, and cortisol levels). The phagocytic activity and index were markedly lowered in fish reared in 15 ppt with continuous TAN exposure, while the lysozyme activity was decreased in fish grown in 5, 10, and 15 ppt with continuous TAN exposure. In conclusion, Nile tilapia showed the possibility of growth with normal health status in brackish water (5–10 ppt); however, continuous TAN exposure can impair the productivity of tilapia, especially with high salinity (15 ppt).

Abstract The durability of a polymer electrolyte membrane (PEM) water electrolysis single cell, assembled with regular porous transport layers (PTLs) is investigated for just over 1000 h. We observe a significant degradation rate of 194 μV h−1 and conclude that 78% of the detectable degradation can be explained by an increase in ohmic resistance, arising from the anodic Ti-PTL. Analysis of the polarization curves also indicates a decrease in the anodic exchange current density, j0, that results from the over-time contamination of the anode with Ti species. Furthermore, the average Pt-cathode particle size increases during the test, but we do not believe this phenomenon makes a significant contribution to increased cell voltages. To validate the anode Ti-PTL as a crucial source of increasing resistance, a second cell is assembled using Pt-coated Ti-PTLs. This yields a substantially reduced degradation rate of only 12 μV h−1, indicating that a non-corroding anode PTL is vital for PEM electrolyzers. It is our hope that forthcoming tailored PTLs will not only contribute to fast progress on cost-efficient stacks, but also to its long-term application of PEM electrolyzers involved in industrial processes.

Abstract The objective of this study was to gain further insight into the characteristic behavior of reaction systems for establishment of intrinsic and effective particle gasification kinetics. A wood-derived char was subjected to the carbon dioxide-containing atmospheres of four different reaction systems: a thermogravimetric analyzer (TGA), a fluidized-bed reactor (FBR), a fixed-bed reactor (FFB) and a drop-tube reactor (DTR). All systems contained the same CO2 partial pressure of 800 mbar at atmospheric pressure. A temperature span from 700 to 1600 °C and residence times from 200 ms to over 8 h were investigated. Reactivities spanning five orders of magnitude were observed. The gasification experiments resulted in the identification of four fundamentally different reaction domains; two were classified as true particle behavior, while the observed reaction rates of the other two domains are mainly dominated by the characteristics of the reaction system applied. The domains were referred to as: chemical control, particle diffusion control, bed diffusion control, and system response control. Within the present work, the occurrence of these reaction domains is discussed in regard to the physical nature of the experiments, and implications towards the measurement of reliable particle kinetics are formulated.

Novel concepts enabling a resilient future power system and their subsequent experimental evaluation are experiencing a steadily growing challenge: large scale complexity and questionable scalability. The requirements on a research infrastructure (RI) to cope with the trends of such a dynamic system therefore grow in size, diversity and costs, making the feasibility of rigorous advancements questionable by a single RI. Analysis of large scale system complexity has been made possible by the real-time coupling of geographically separated RIs undertaking geographically distributed simulations (GDS), the concept of which brings the equipment, models and expertise of independent RIs, in combination, to optimally address the challenge. This paper presents the outputs of IEEE PES Task Force on Interfacing Techniques for Simulation Tools towards standardization of GDS as a concept. First, the taxonomy for setups utilized for GDS is established followed by a comprehensive overview of the advancements in real-time couplings reported in literature. The overview encompasses fundamental technological design considerations for GDS. The paper further presents four application oriented case studies (real-world implementations) where GDS setups have been utilized, demonstrating their practicality and potential in enabling the analysis of future complex power systems.

Today’s investment decisions in large-scale onshore wind projects in Germany are no longer determined only by the investment’s economic benefit, but also by concerns associated to social acceptance. Despite a mostly positive attitude towards the expansion of wind power, local public concerns often stem from the belief that the proximity to large-scale wind farms may lead to a decrease in property prices. In particular, the change in landscape caused by the construction of a wind farm may have an adverse impact on the view from some properties, and thus may negatively affect their price. To investigate the potential devaluation of properties in Germany due to wind farms, we use a quasi-experimental technique and apply a spatial difference-in-differences approach to various wind farm sites in the federal state of North Rhine-Westphalia. We adopt a quantitative visual impact assessment approach to account for the adverse environmental effects caused by the wind turbines. To properly account for spatial dependence and unobserved variables biases, we apply augmented spatial econometric models. The estimates indicate that the asking price for properties whose view was strongly affected by the construction of wind turbines decreased by about 10-17%. In contrast, properties with a minor or marginal view on the wind turbines experienced no devaluation.