Search Results (423)

This study evaluates the techno-economic feasibility of integrating wind power with hydrogen-based storage to decarbonize the Raglan Mine in northern Canada. Using HOMER simulations with real 2021 operational data, six progressive scenarios were modeled, ranging from partial substitution of diesel generators to complete site-wide electrification, including heating, transport, and mining equipment. Results show that complete decarbonization (Scenario 6) is technically achievable and could avoid up to 143,000 tCO₂eq annually (~2.15 Mt over 15 years), but remains economically prohibitive under current technology costs. In contrast, Scenario 2 Case 2, which combines solid oxide fuel cells with thermal charge controllers, emerges as the most viable near-term pathway, avoiding ~61,000 tCO₂eq annually (~0.91 Mt over 15 years) while achieving improved return on investment. A qualitative multi-criteria framework highlights this configuration as the best trade-off between technical feasibility, environmental performance, and economic viability. At the same time, complete decarbonization remains a longer-term target contingent on cost reductions and policy support. Overall, the findings provide clear evidence that hydrogen storage, when coupled with wind power, can deliver substantial and measurable decarbonization benefits for Arctic mining operations. Full article

Aromaticity tuning of biaryl monophosphines can significantly impact their catalytic performance. Biaryl monophosphines constitute a crucial class of compounds due to their potential as ligand precursors in asymmetric Pd-catalyzed cross-coupling and some other catalytic reactions. In this study, we investigate the tuning of aromaticity within a series of selected biaryl monophosphine derivatives exhibiting diverse steric and electronic properties. XRD structures and Hirshfeld surface analyses were complemented by DFT calculations. Aromaticity indices, such as geometric HOMA, HOMER, and magnetic NICS, were evaluated and correlated with ligand properties. NICS(1)zz was the most sensitive to aromaticity changes. The results showed that among the ring-activating substituents, methoxy groups were more beneficial than hydroxy ones. The hydroxy groups not only modulated the aromaticity but also induced unfavorable conformational changes of the catalyst precursors through strong inter- and intramolecular hydrogen bonding. The spatial arrangement of the P atom adjacent to the aryl ring system confers catalytic advantages by promoting the assembly of coordination compounds (catalysts) in which Pd—C bond formation occurs, yielding C,P-chelated five-membered palladacyclic structures. The hydroxy substituents blocked access to the P atom, thereby hindering catalytic performance. The studies show that even subtle changes in the monophosphine biaryl scaffold, especially aromaticity tuning should be carefully evaluated during the rational design of new efficient catalysts. The studied compounds were evaluated for their biological activity against three Gram-positive and four Gram-negative bacteria as model microorganisms. The research was supplemented by in vitro cytotoxicity evaluation. Full article

A novel methodology for hybrid energy management in aquaculture is introduced, aimed at enhancing self-sufficiency and optimizing grid-related cash flows. Wind and solar energy generation are modeled using calibrated turbine performance curves and PVGIS data, respectively, with a photovoltaic capacity of 120 kWp. The system also incorporates a 250 kW small hydroelectric plant and a wood drying kiln that utilizes surplus wind energy. This study conducts a comparative analysis between HY4RES, a research-oriented simulation model, and HOMER Pro, a commercially available optimization tool, across multiple hybrid energy scenarios at two aquaculture sites. For grid-connected configurations at the Primary site (base case, Scenarios 1, 2, and 6), both models demonstrate strong concordance in terms of energy balance and overall performance. In Scenario 1, a peak power demand exceeding 1000 kW is observed in both models, attributed to the biomass kiln load. Scenario 2 reveals a 3.1% improvement in self-sufficiency with the integration of photovoltaic generation, as reported by HY4RES. In the off-grid Scenario 3, HY4RES supplies an additional 96,634 kWh of annual load compared to HOMER Pro. However, HOMER Pro indicates a 3.6% higher electricity deficit, primarily due to battery energy storage system (BESS) losses. Scenario 4 yields comparable generation outputs, with HY4RES enabling 6% more wood-drying capacity through the inclusion of photovoltaic energy. Scenario 5, which features a large-scale BESS, highlights a 4.7% unmet demand in HY4RES, whereas HOMER Pro successfully meets the entire load. In Scenario 6, both models exhibit similar load profiles; however, HY4RES reports a self-sufficiency rate that is 1.3% lower than in Scenario 1. At the Secondary site, financial outcomes are closely aligned. For instance, in the base case, HY4RES projects a cash flow of 54,154 EUR, while HOMER Pro estimates 55,532 EUR. Scenario 1 presents nearly identical financial results, and Scenario 2 underscores HOMER Pro’s superior BESS modeling capabilities during periods of reduced hydroelectric output. In conclusion, HY4RES demonstrates robust performance across all scenarios. When provided with harmonized input parameters, its simulation results are consistent with those of HOMER Pro, thereby validating its reliability for hybrid energy management in aquaculture applications. Full article

I offer a close reading of Hölderlin’s “Mnemosyne“ (“Reif sind, in Feuer getaucht…”) that situates it in terms of its links to Greek tragedy and Homer. The essay explores Hölderlin’s focus on Achilles and the death of the Greek heroes Patroklos and Ajax against the notion of “poetic transport.” I also look at Hölderlin’s 2nd Böhlendorff Letter that traffics in the relation between antiquity and modernity. The essay also offers a reading of the second stanza of “Mnemosyne” in terms of Rousseau’s essay on “The Reveries of the Solitary Walker” and its appeal to the poet. As Hölderlin pursues the tense relation between memory and death, he poses questions about ethical responsibility that challenge the human being to find a path between wallowing in too excessive grief that ends in unbounded subjectivity and affirming the sense of the other that extends beyond our own self-preoccupation. Full article

Jordan Vision prioritizes the utilization of domestic resources, particularly renewable energy. The transportation sector, responsible for 49% of national energy consumption, remains central to this transition and accounts for around 28% of total greenhouse gas emissions. Electric vehicles (EVs) offer a promising solution to reduce waste and pollution, but they also pose challenges for grid stability and charging infrastructure development. This study addresses a critical gap in the planning of renewable-powered EV charging stations along Jordanian highways, where EV infrastructure is still limited and underdeveloped, by optimizing the design of a hybrid energy charging station using HOMER Grid (v1.9.2) Software. Region-specific constraints and multiple operational scenarios, including rooftop PV integration, are assessed to balance cost, performance, and reliability. This study also investigates suitable locations for charging stations along the Sahrawi Highway in Jordan. The proposed station, powered by a hybrid system of 53% wind and 29% solar energy, is projected to generate 1.466 million kWh annually at USD 0.0375/kWh, reducing CO₂ emissions by approximately 446 tonnes annually. The findings highlight the potential of hybrid systems to increase renewable energy penetration, support national sustainability targets, and offer viable investment opportunities for policymakers and the private sector in Jordan. Full article

This study models different hybrid systems based on renewable energies that can be supported by diesel generators to meet the energy needs of isolated homes in the Canary Islands. The research will cover the energy requirements of a residential house, including the production of fresh water using a reverse osmosis desalination plant. The system is designed to operate independently of the electrical grid. The HOMER software package was used to model and optimize the hybrid systems. The model was fed with data on the electrical demands of residential homes (including the consumption by the small reverse osmosis desalination plant) as well as the technical specifications of the various devices and renewable energy sources, such as solar radiation and wind speed potentials. The software considers various configurations to optimize hybrid systems, selecting the most suitable one based on the available renewable energy sources at the selected location. The data used in the research were collected on the eastern islands of the Canary Islands (Gran Canaria, Lanzarote and Fuerteventura). Based on the system input parameters, the simulation and optimization performed in HOMER, taking into account the lowest “Levelized Cost of Energy”, it can be concluded that the preferred hybrid renewable energy system for this region is a small wind turbine with a nominal power of 1.9 kW, eight batteries, and a small diesel generator with a nominal power of 1.0 kW. The knowledge from this research could be applied to other geographical areas of the world that have similar conditions, namely a shortage of water and plentiful renewable energy sources. Full article

Microgrids (MGs) have emerged as pivotal players in the energy transition by enabling the efficient integration of distributed energy resources and the provision of ancillary services to the power system. Despite their technical capabilities, MGs still face economic and regulatory barriers that hinder their widespread deployment in electricity markets. This paper presents a structured methodological framework to assess the economic viability of MGs delivering services such as peak shaving, loss compensation, and voltage support, among others. The proposed approach considers three distinct scenarios: (1) MGs supplying energy to local loads, (2) hybrid MGs combining local supply with ancillary services, and (3) MGs exclusively dedicated to ancillary services. The framework incorporates adjusted levelized cost of electricity (LCOE), levelized avoided cost of electricity (LACE), and net value metrics, while accounting for tax incentives and market price signals. A case study based in Colombia (Cali and Camarones) validates the framework through simulations conducted in HOMER Pro V3.18.4 and MATLAB Online. The results indicate that remuneration schemes based on availability and service utilization significantly enhance the viability of MGs. The proposed methodology is applicable to emerging regulatory environments and offers guidance for designing public policies that promote the active participation of MGs in supporting grid operations. Full article

Sudan’s rural regions face acute challenges in energy access, exacerbated by ongoing conflict that has destroyed major power infrastructure and crippled conventional electricity generation. This study investigates the technical and economic feasibility of photovoltaic (PV) solar systems as a sustainable alternative for powering off-grid rural communities. Using MATLAB simulations (Version 24b), Global Solar Atlas data, and HOMER software (Version 4.11) for hybrid system optimization, a case study of a village in Shariq al-Nil, Khartoum, demonstrates the viability of solar energy to meet residential, medical, and agricultural needs. Beyond technical analysis, this paper highlights the transformative role of solar energy in post-conflict reconstruction, with potential applications in powering irrigation systems and supporting agricultural livelihoods. It also emphasizes the importance of integrating community-centered policy frameworks to ensure equitable access, long-term adoption, and sustainable development outcomes. The findings advocate for policies that support renewable energy investment as a cornerstone of rebuilding efforts in Sudan and similar contexts affected by conflict and infrastructure collapse. Full article

Water and energy are strongly intertwined, especially in wastewater treatment plants (WWTPs) whose electrical loads can strain local grids. This work evaluates the technical, economic, and environmental feasibility of powering the WWTP attached to the smart building of Ibn Tofail University (Morocco) with building-integrated photovoltaics (PV) and a complementary wind turbine. Using the HOMER Pro optimizer, two configurations were compared: (i) stand-alone PV and (ii) a hybrid PV/wind system. The hybrid design raises the renewable energy fraction from 8.5% to 17.9%, cutting annual grid purchases by 8% and avoiding 47.9 t CO₂ yr⁻¹. The levelized cost of electricity decreases from 1.08 to 0.97 MAD kWh⁻¹ (≈0.11 to 0.10 USD kWh⁻¹), while the net present cost drops by 6%. Sensitivity analyses confirm robustness under grid electricity tariff and load-growth uncertainties. These results demonstrate that modest wind additions can double the renewable share and improve economics, offering a replicable pathway for WWTPs and smart buildings across the MENA region. Full article

For millennia, since Homer to postmodern theatre, the world has been imagined as a stage and life as a play. The truth of this metaphor, however, rests on mere assertions. This essay assesses the validity of this metaphor by examining drama as enactment. To this end, in dialogue with Derrida, this study elaborates on Schechner’s view of the liminality of acting and von Balthasar’s conception of death as ‘the center of acting area.’ It argues that the spectrality of existence constitutes the liminality of life as an enactment as much as it defines the world as a stage. This essay begins with a broad survey of the idea of theatrum mundi across cultures to demonstrate the significance of role enactment. It then traces how Schechner, drawing on Van Gennep and Turner, develops the notion of liminality to articulate the ambiguity of enactment as an indispensable part of acting. Finally, it engages with the interplay of life and death—or lavielamort in Derrida’s terms—as observed in von Balthasar’s dramatic framework, and maintains that the spectrality of existence accounts for the liminality of role enactment in the world as a cosmic theatre. Full article

The escalating global demand for electricity, coupled with environmental concerns and economic considerations, has driven the exploration of alternative energy sources, creating competition for land with other sectors. A comprehensive analysis of a 10 MW floating photovoltaic (FPV) system deployed across different Köppen climate zones along with techno-economic analysis involves evaluating technical efficiency and economic viability. Technical parameters are assessed using PVsyst simulation and HOMER Pro. While, economic analysis considers return on investment, net present value, internal rate of return, and payback period. Results indicate that temperate and dry zones exhibit significant electricity generation potential from an FPV. The study outlines the payback period with the lowest being 5.7 years, emphasizing the system’s environmental benefits by reducing water loss in the form of evaporation. The system is further integrated with hydrogen generation while estimating the number of cars that can be refueled at each location, with the highest amount of hydrogen production being 292,817 kg/year, refueling more than 100 cars per day. This leads to an LCOH of GBP 2.84/kg for 20 years. Additionally, the comparison across different Koppen climate zones suggests that, even with the high soiling losses, dry climate has substantial potential; producing up to 18,829,587 kWh/year of electricity and 292,817 kg/year of hydrogen. However, factors such as high inflation can reduce the return on investment to as low as 13.8%. The integration of FPV with hydropower plants is suggested for enhanced power generation, reaffirming its potential to contribute to a sustainable energy future while addressing the UN’s SDG7, SDG9, SDG13, and SDG15. Full article

Myanmar’s electricity supply relies mainly on hydropower and gas-fired generation, yet rural electrification remains limited, with national access at approximately 60%. The National Electrification Plan (NEP) aims for universal access via nationwide grid expansion, but progress in remote areas is constrained by financial limits and suspended external funding. This study evaluates the techno-economic feasibility of decentralized microgrids as an alternative to conventional grid extension under current budgetary conditions. We integrate a terrain-adjusted MV line-cost model with (i) PLEXOS capacity expansion and chronological dispatch for centralized supply and (ii) HOMER Pro optimization for PV–diesel–battery microgrids. Key indicators include LCOE, NPC, CAPEX, OPEX, reliability (ASAI/max shortage), renewable fraction, and unserved energy. Sensitivity analyses cover diesel, PV, and battery prices, as well as discount rate variations. The results show microgrids are more cost-effective in terrain-constrained regions such as Chin State, particularly when accounting for transmission and delayed generation costs, whereas grid extension remains preferable in flat, accessible regions like Nay Pyi Taw. Diesel price is the dominant cost driver across both regions, while battery cost and discount rate affect Chin State more, and PV cost is critical in Nay Pyi Taw’s solar-rich context. These findings provide evidence-based guidance for rural electrification strategies in Myanmar and other developing countries facing similar financial and infrastructural challenges. Full article

Newfoundland and Labrador have strong wind and water resources, making hybrid renewable energy systems an important option for the region. This paper presents the design and simulation of a system that combines wind turbines and micro-hydro power to deliver clean electricity for water treatment in remote communities. Many isolated areas still rely on diesel and other conventional sources, which create environmental concerns. Using HOMER Pro 3.17.1 software, the system was modeled based on local climate and resource conditions. Results show that it can produce over 35,000 kWh per year, enough to power a standard water treatment unit serving more than 240 people. By integrating wind and hydro with battery storage, the system ensures stable operation and reduces dependence on fossil fuels. The environmental analysis confirms that it avoids over 9 tons of CO₂ emissions annually. The novelty of this work is its site-specific approach, showing how renewable energy can improve both energy security and water quality in remote Canadian communities while providing a model for sustainable rural development. Full article

Access to renewable energy is vital for rural development and climate change mitigation. The intermittency of renewable sources necessitates efficient energy storage, especially in off-grid applications. This study evaluates the technical, economic, and environmental performance of an off-grid hybrid system for the rural settlement of Soma, Turkey. Using HOMER Pro 3.14.2 software, a system consisting of solar, wind, battery, and hydrogen components was modeled under four scenarios with Cyclic Charging (CC) and Load Following (LF) control strategies for optimization. Life cycle assessment (LCA) and hydrogen leakage impacts were calculated separately through MATLAB R2019b analysis in accordance with ISO 14040 and ISO 14044 standards. Scenario 1 (PV + wind + battery + H₂) offered the most balanced solution with a net present cost (NPC) of USD 297,419, with a cost of electricity (COE) of USD 0.340/kWh. Scenario 2 without batteries increased hydrogen consumption despite a similar COE. Scenario 3 with wind only achieved the lowest hydrogen consumption and the highest efficiency. In Scenario 4, hydrogen consumption decreased with battery reintegration, but COE increased. Specific CO₂ emissions ranged between 36–45 gCO₂-eq/kWh across scenarios. Results indicate that the control strategy and component selection strongly influence performance and that hydrogen-based hybrid systems offer a sustainable solution in rural areas. Full article

Thyroid hormones (THs) are essential for brain development, and their dysregulation is associated with cognitive deficits and neurodevelopmental disorders. Down syndrome (DS), caused by trisomy 21, is frequently associated with thyroid dysfunction and impaired neurogenesis. Here, we investigated THs signaling dynamics during neural differentiation using human induced pluripotent stem cells (hiPSCs) derived from individuals with DS and controls. We analyzed the gene expression of key THs regulators—deiodinases, transporters, and receptors—and downstream target genes in hiPSCs, hiPSC-derived neural progenitor cells (NPCs), hiPSC-derived astrocytes, and hiPSC-derived neurons. DS-derived hiPSCs, hiPSC-derived NPCs, and hiPSC-derived neurons exhibited 2- to 7-fold increases in the gene expression of DIO2 and 3- to 8-fold reductions in DIO3, alongside 1- to 3-fold downregulation of THRA and THRB isoforms. hiPSC-derived astrocytes showed a 4-fold decrease in the gene expression of DIO2, a 4-fold increase in DIO3, upregulation of SLC16A10 (2-fold), and downregulation of SLC7A5 (0.5-fold) and THs receptors (0.5- to 12-fold). hiPSC-derived neurons exhibited marked downregulation of the gene expression of HOMER1 (0.5-fold), GRIN3A (14-fold), and GRIN3B (4-fold), accompanied by impaired spontaneous activity in multi-electrode array recordings. These findings reveal a robust, cell-type-specific imbalance between THs availability and signaling competence in DS hiPSC-derived neural cells, providing mechanistic insight into THs-related contributions to the function of DS hiPSC-derived neural cells and identifying potential therapeutic targets. Full article