Escalating Energy Demand Research Articles

Maximizing microbial activity and synergistic interaction to boost biofuel production from lignocellulosic biomass.

Addressing global environmental challenges and meeting the escalating energy demands stand as two pivotal issues in the current landscape. Lignocellulosic biomass emerges as a promising renewable bio-energy source capable of fulfilling the world's energy requirements on a large scale. One of the most important steps in lowering reliance on fossil fuel and lessening environmental effect is turning lignocellulosic biomass into biofuel. As carbon-neutral substitutes for traditional fuel, biofuel offer a solution to environmental concerns compared to conventional fuel. Effective utilization of lignocellulosic biomass is imperative for sustainable development. Ongoing research focuses on exploring the potential of various microorganisms and their co-interactions to synthesize diverse biofuels from different starting materials, including lignocellulosic biomass. Co-culture techniques demonstrate resilience to nutrient scarcity and environmental fluctuations. By utilising a variety of carbon sources, microbes can enhance their adaptability to environmental stressors and potentially increase productivity through their symbiotic interactions. Furthermore, compared to single organism involvement, co-interactions allow faster execution of multistep processes. Lignocellulosic biomass serves as a primary substrate for pre-treatment, fermentation, and enzymatic hydrolysis processes. This review primarily delves into the pretreatment, enzymatic hydrolysis process and the biochemical pathways involved in converting lignocellulosic biomass into bioenergy.

Enhancing Electrochemical Performance of Si@CNT Anode by Integrating SrTiO3 Material for High-Capacity Lithium-Ion Batteries

Silicon (Si) has attracted worldwide attention for its ultrahigh theoretical storage capacity (4200 mA h g−1), low mass density (2.33 g cm−3), low operating potential (0.4 V vs. Li/Li+), abundant reserves, environmentally benign nature, and low cost. It is a promising high-energy-density anode material for next-generation lithium-ion batteries (LIBs), offering a replacement for graphite anodes owing to the escalating energy demands in booming automobile and energy storage applications. Unfortunately, the commercialization of silicon anodes is stringently hindered by large volume expansion during lithiation–delithiation, the unstable and detrimental growth of electrode/electrolyte interface layers, sluggish Li-ion diffusion, poor rate performance, and inherently low ion/electron conductivity. These present major safety challenges lead to quick capacity degradation in LIBs. Herein, we present the synergistic effects of nanostructured silicon and SrTiO3 (STO) for use as anodes in Li-ion batteries. Si and STO nanoparticles were incorporated into a multiwalled carbon nanotube (CNT) matrix using a planetary ball-milling process. The mechanical stress resulting from the expansion of Si was transferred via the CNT matrix to the STO. We discovered that the introduction of STO can improve the electrochemical performance of Si/CNT nanocomposite anodes. Experimental measurements and electrochemical impedance spectroscopy provide evidence for the enhanced mobility of Li-ions facilitated by STO. Hence, incorporating STO into the Si@CNT anode yields promising results, exhibiting a high initial Coulombic efficiency of approximately 85%, a reversible specific capacity of ~800 mA h g−1 after 100 cycles at 100 mA g−1, and a high-rate capability of 1400 mA g−1 with a capacity of 800 mA h g−1. Interestingly, it exhibits a capacity of 350 mAh g−1 after 1000 lithiation and delithiation cycles at a high rate of 600 mA hg−1. This result unveils and sheds light on the design of a scalable method for manufacturing Si anodes for next-generation LIBs.

Efficient Permeable Monolithic Hybrid Tribo-Piezo-Electromagnetic Nanogenerator Based on Topological-Insulator-Composite.

Escalating energy demands of self-independent on-skin/wearable electronics impose challenges on corresponding power sources to offer greater power density, permeability, and stretchability. Here, a high-efficient breathable and stretchable monolithic hybrid triboelectric-piezoelectric-electromagnetic nanogenerator-based electronic skin (TPEG-skin) is reported via sandwiching a liquid metal mesh with two-layer topological insulator-piezoelectric polymer composite nanofibers. TPEG-skin concurrently extracts biomechanical energy (from body motions) and electromagnetic radiations (from adjacent appliances), operating as epidermal power sources and whole-body self-powered sensors. Topological insulators with conductive surface states supply notably enhanced triboelectric and piezoelectric effects, endowing TPEG-skin with a 288V output voltage (10 N, 4Hz), ∼3 times that of state-of-the-art devices. Liquid metal meshes serve as breathable electrodes and extract ambient electromagnetic pollution (±60V, ±1.6µA cm-2). TPEG-skin implements self-powered physiological and body motion monitoring and system-level human-machine interactions. This study provides compatible energy strategies for on-skin/wearable electronics with high power density, monolithic device integration, and multifunctionality.

Feasibility of realizing photothermal, photovoltaic, and radiative cooling with a flexible structure

The escalating energy demands and the imperative of environmental conservation necessitate advanced sustainable energy solutions. This study introduces a novel nanofluid spectrum-splitting photovoltaic/thermal system integrated with radiative cooling (RC) technology, termed NSS-RC-PV/T. This system optimizes solar spectrum utilization, enhances thermal management, and significantly improves the efficiency and flexibility of heat, electricity, and cooling outputs. Employing a reversible PV-Ag panel, the system adapts between PV/T and RC modes based on energy demands. A comprehensive mathematical model is established to evaluate its performance under realistic environmental conditions across China. Results indicate the maximum energy output of the system is 6438 MJ/m2, which is a 33.4% increase in annual energy output compared to the conventional PV/T system. The dynamic power response model also shows an increase of 5.8% (266 MJ/m2) compared to the daylight response model. This research underscores the potential of NSS-RC-PV/T systems in advancing renewable energy technologies and meeting modern energy needs.

The impact of renewable and non-renewable energy consumption on aggregate output in Pakistan: robust evidence from the RALS cointegration test.

Over the past three decades, Pakistan's energy consumption has surged due to industrialization, population growth, and development activities. To meet the escalating energy demands, the country has primarily relied on thermal power projects, which are financially burdensome and environmentally detrimental, compared to hydropower projects. This reliance exposes Pakistan to global oil price shocks and environmental degradation. To address this dilemma, this empirical research investigates the impact of both non-energy factors (labour and capital) and energy-specific factors (renewable and non-renewable) on Pakistan's aggregate output, using annual time-series data from 1980 to 2021. The analysis employs the newly established Residual Augmented Least Square (RALS) cointegration test and the Autoregressive Distributed Lag (ARDL) methodology to estimate the long-term cointegrating relationship among the examined variables. The empirical findings demonstrate that both non-energy and energy-specific factors positively and significantly influence Pakistan's long-term aggregate output. However, petroleum consumption exerts a positive but insignificant influence on Pakistan's long-term aggregate output. The study recommends diversifying the energy supply mix to include more hydroelectricity, non-hydroelectric renewables (mainly solar and wind), and natural gas. Specifically, transitioning from imported, expensive, and more greenhouse gas (GHG)-generating petroleum products to domestically produced natural gas could potentially reduce Pakistan's trade deficit and its vulnerability to global oil price shocks. Besides the economic benefits, shifting from non-renewable energy sources (specifically oil) to renewable energy would enhance Pakistan's image and increase its geopolitical influence over neighboring countries. Additionally, the study emphasizes the need to encourage private sector participation in renewable energy projects and suggests implementing effective carbon tax policies to mitigate CO2 emissions and foster economic growth.

Battery energy storage with renewable energy sources integration in unbalanced distribution network considering time of use pricing

The increasing demand for sustainable energy solutions and the escalating energy demand have facilitated the emergence of renewable energy sources (RES), such as photovoltaic (PV) sources. Combining RES with battery energy storage system (BESS) technology reduces peak hour demand and allows for economical charging and discharging for time-based energy pricing. Integrating PV and BESS in an unbalanced system with multiple RES sources is a challenging task. It requires a robust algorithm to minimise power loss in the distribution system and decrease the voltage unbalance factor (VUF). This paper presents a new multi-objective Pelican optimisation algorithm (MOPOA) for the optimal allocation of PV and BESS. The MOPOA helps find the best placement of PV and BESS in an IEEE-33 bus unbalanced radial distribution system (URDS). The proposed algorithm combines multiple benefits from a lower net present cost (NPC) and a higher voltage profile enhancement index (VPEI). The case studies and simulation results show that the proposed method places PV and BESS in IEEE 33-bus URDS optimally, satisfying all of the system’s requirements. The results indicate an improvement in the minimum VUF factor of 4.4% in a winter day and 4.3% in a summer day; a reduction in active power loss of 16% in a winter day and 7.1% in a summer day; and a reduction in reactive power loss of 7.5% in a winter day and 7.2% in a summer day. Thus, the recommended strategy effortlessly accelerates to a suboptimal solution.

Investigations on thermal profiles and flow structures in a square channel equipped with staggered vortex turbulators

Given the escalating energy demands today, improving the efficiency of engineering equipment is crucial for optimizing energy use. This study focuses on enhancing heat exchanger performance through passive methods, particularly by installing vortex turbulators. Passive techniques can effectively manage energy costs while enhancing efficiency.The research examines thermal profiles and airflow structures within a square channel heat exchanger (SCHE) equipped with staggered vortex turbulators (SVTs). SVTs feature a unique design combining rectangular winglets and V-pattern baffles. The installation of SVTs aims to intensify vortex strength, thereby increasing SCHE efficiency, convective heat transfer coefficients, and overall heat transfer potential. The study investigates the effects of SVT dimensions (b1/H and b2/H), airflow directions (+x and -x), installation patterns (pattern no. 1 and 2), pitch to height ratios (P/H = 1, 1.5, and 2), and flow attack angles (α = 20°, 30°, and 45°). Computational simulations using the finite volume method with a commercial code (FLUENT) under laminar flow conditions (Reynolds number of 100–2000) provide insights into thermal profiles, fluid temperature distributions, and flow configurations within the SCHE. Staggered arrangement and gap spacing are employed to reduce pressure loss and enhance airflow strength. The results highlight flow structures and heat transfer characteristics in the heat exchanger channels, elucidating the underlying mechanisms of the heat exchange process. Understanding these behaviors is crucial for developing more efficient heat exchangers and vortex generators in the future. Simulation findings demonstrate that SVTs significantly enhance convective heat transfer over smooth channels due to increased vortex strength. Notably, pattern no. 2 SVTs (b1/H = b2/H = 0.20) achieve the highest Nu/Nu0 of 19.21 in the +x flow direction at Re = 2000, α = 30°, and P/H = 1. In conclusion, the study identifies a maximum thermal enhancement factor of 4.38. It underscores the potential of pattern no. 2 SVTs for optimizing heat exchanger performance, offering valuable insights for future developments in thermal management technologies.

Integrated membrane distillation and absorption chiller driven by solar energy: Concept and analysis

Solar energy linked to absorption chiller system is used to supply the heating and cooling energies to membrane distillation (MD) process. The heating load is taken directly from the solar energy system. The cooling load is provided by the absorption chiller system, which converts the solar energy into refrigeration power. Using a solar collector area of 60 m2 and MD feed flow rate of 600 kg/h, the maximum distillate production for a single MD can reach 61.5 kg/h, which corresponds to a recovery ratio of 10.2% and a gain output ratio (GOR) of 3.2. Increasing the MD feed flow rate necessitates enlarging the solar collector area to meet the escalating energy demand. An additional MD unit was also integrated and powered by the internal energy of the absorption chiller system. The total distillate production approaches 83 kg/h and the GOR enhances to 4.5. The condenser stream of the two integrated MD units is quenched by the refrigeration power of the absorption chiller system under split and joint scenarios. The split scenario was found to outperform the joint option in terms of providing higher average distillate production over the period of daily sunshine hours. However, the joint scenario can activate both MD units only if a larger solar collector of 100 m2 is employed and the condenser of the absorption chiller system is operated at 40 °C. Similarly, the split scenario can activate the two MD units only if split ratio equal or higher than 60% is enforced.

(Nanocarbons Division Poster Award, 3rd Place) Investigating the Impact of Reaction and Carbonization Variables on ZIF-67 and Its Energy Storage Properties

Metal-organic frameworks (MOFs), with their exceptional properties such as high surface area, well-defined pores, and diverse chemical functionalities, have garnered widespread attention in scientific and industrial domains [1-2]. Among these, zeolitic imidazolate frameworks (ZIFs), known for their chemical and thermal stability, are extensively explored for applications ranging from catalysis and gas adsorption to electronic devices and sensors.By employing a novel hydrothermal method in aqueous solutions at room temperature, ZIF-67 nanocrystals were successfully synthesized, eliminating the need for toxic organic solvents and reducing overall costs. The resulting materials demonstrated notable efficiency in energy storage. To address the increasing demand for scalable synthesis methods, the study investigated the impact of reaction scale, reaction time, and reaction mixture dilution on the yield, morphology, and molecular structure of ZIF-67. The optimized conditions increased the production yield to 83%, surpassing the reported 75%. The subsequent carbonization process under three different regimes (800 °C, 800 °C with 3h ramp, 900 °C) resulted in materials exhibiting promising energy storage capabilities, with capacitance values reaching 81 F g−1 at a low sweep rate of 5 mV s−1. The carbonization yield showed a decrease with increasing carbonization time and temperature, and capacitance values were influenced by the presence of cobalt in the material.A slightly higher specific surface area of sample C-800 is reflected in the slightly higher capacitance values over all sweep rates indicating that specific surface area plays a role in the behavior of here synthesized materials. Capacitance is invariant at higher sweep rates (above 20mV s-1) which can be an indication that a part of the material surface, at macro- and mesopores, is highly responsive and highly conductive. At lower sweep rates micropores become available, due to prolonged time for ion insertion, which increases the capacitance that is unavailable at higher sweep rates. The highest percentage rise in capacitance is also seen in sample C-800 as its micropore volume, 40% of its total volume, is the highest among the samples investigated.Specifically, considering only the carbon part, the specific capacitance reached 176 F g−1, comparable to literature values for MOF-derived carbons [3]. The study suggests that dissolution of cobalt could enhance the material's capacitance behavior, opening avenues for further improvement in energy storage applications. This transformative approach addresses challenges associated with escalating energy demands and showcases the potential of ZIF-67-derived materials in electrochemical applications.AcknowledgementThis research was supported by the Science Fund of the Republic of Serbia, grant number 7750219, Advanced Conducting Polymer-Based Materials for Electrochemical Energy Conversion and Storage, Sensors and Environmental Protection-AdConPolyMat (IDEAS programme)

La0.8Sr0.2CoO3 Electrocatalyst for Oxygen Evolution Reaction in Alkaline Electrolysis: From Powder to the Fuel Cell Application

In recent years, there has been a growing need for new renewable energy sources due to the rapid depletion of conventional energy sources and an escalating energy demand. Since environmental protection concerns are increasing, electrochemical processes are becoming increasingly essential [1]. Specifically, the focus has shifted towards storing energy in hydrogen and its subsequent conversion into on-demand electricity [2]. Here, hydrogen, generated via water electrolysis, serves as either an intermediary for generating energy carriers like liquid fuels or plays a key role as an energy carrier [3]. Despite significant efforts focused on enhancing electrolyzers for energy conversion, the progression towards practical application has encountered challenges stemming from differing catalyst development requisites in academic and industrial research. This study proposes a systematic approach for efficiently transitioning electrocatalysts from fundamental research to application readiness for alkaline oxygen evolution reactions.Herein, La0.8Sr0.2CoO3 was chosen as a catalyst and compared with the benchmark material NiFe2O4. Initially, the La0.8Sr0.2CoO3 catalyst was successfully synthesized by scalable spray-flame synthesis. Following this, various inks were formulated utilizing different binders (Nafion®, Naf; Sustainion®, Sus). The dispersion stability of La0.8Sr0.2CoO3 and commercial NiFe2O4 inks was investigated in the presence of Nafion and Sustainion using analytical centrifugation and transmittograms. Subsequently, these selected dispersions were applied onto nickel substrates via spray coating techniques, ensuring a homogeneous catalyst distribution. Finally, the La0.8Sr0.2CoO3 and NiFe2O4 catalysts were subjected to extensive electrochemical evaluations, including glassy carbon rotating disk electrode, scanning droplet cell (SDC), compression cell, flow cell, and zero-gap cell, to evaluate the material performance. SDC findings highlight the excellent uniformity in La0.8Sr0.2CoO3 electrodes and NiFe2O4-Sustainion (standard deviation < 11%). However, the NiFe2O4-Sustainion film experienced delamination, exhibiting a standard deviation of 28%. SDC experiments offer advantages over various half-cell techniques by enabling the detection of any inhomogeneities or coating defects within the catalytic film. Additionally, complementary compression and flow cell experiments provide detailed information on the chemical and mechanical stress parameters resembling those in a full cell configuration. In assessing industrial applicability, the catalytic materials were undergone examination within a scalable full cell under industrial conditions (500 mA/cm² and 60 °C) utilizing a zero-gap cell setup. The observed trend in the full cell for the coated electrodes is as follows: La0.8Sr0.2CoO3-Naf > La0.8Sr0.2CoO3-Sus > NiFe2O4-Sus > NiFe2O4-Naf.These findings achieved through a well-structured coherent workflow, enhance our knowledge of the electrocatalytic system and offer essential insights for implementing novel materials in large-scale industrial applications. REFERENCES: [1] M.-S. Park, J. Kim, K.J. Kim, J.-W. Lee, J.H. Kim, Y. Yamauchi, Porous nanoarchitectures of spinel-type transition metal oxides for electrochemical energy storage systems, Phys. Chem. Chem. Phys. 17 (2015) 30963–30977. https://doi.org/10.1039/C5CP05936D.[2] J.R. Varcoe, P. Atanassov, D.R. Dekel, A.M. Herring, M.A. Hickner, P.A. Kohl, A.R. Kucernak, W.E. Mustain, K. Nijmeijer, K. Scott, T. Xu, L. Zhuang, Anion-exchange membranes in electrochemical energy systems, Energy Environ. Sci. 7 (2014) 3135–3191. https://doi.org/10.1039/C4EE01303D.[3] C. Van Pham, D. Escalera-López, K. Mayrhofer, S. Cherevko, S. Thiele, Essentials of High Performance Water Electrolyzers – From Catalyst Layer Materials to Electrode Engineering, Adv. Energy Mater. 11 (2021) 2101998. https://doi.org/https://doi.org/10.1002/aenm.202101998.

Dual function sMoS2-cellulose/PVDF-based membrane for energy generation and pollutant removal

Fostering the creation of clean energy technologies that eliminate gas emissions and positively impact the environment is vital for confronting the dual challenges of escalating energy demands and environmental contaminants. Membrane-based technologies have emerged as effective strategies for harvesting clean energy and practically purifying water from contaminated wastewater. Here, we show that polyvinylidene difluoride (PVDF) with functionalized molybdenum disulfide (sMoS2) and nanocellulose (NC) is an attractive membrane for single-chamber air cathode microbial fuel cells (MFCs). Compared with conventional proton exchange membranes, our membrane boosts power generation up to 48.5 mW m−2 and efficiently catalyzes sonocatalytic dye degradation with 96 % efficiency when treating wastewater. This performance is due to a relatively high hydrophilicity, ion exchange capacity (0.84 meq. g−1), and proton conductivity (1.03 × 10−2 S cm−1), combined with reduced oxygen permeability (27 × 1012 cm s−1) compared with conventional membranes. The synergy effect of the PVDF matrix and sMoS2 + NC promotes proton transfer, enhancing electricity generation and pollutant degradation. The membrane shows promising stability and mechanical properties, offering a viable membrane for improved energy recovery from wastewater treatment.

Photovoltaic energy harvesting booster under partially shaded conditions using MPPT based sand cat swarm optimizer

Photovoltaic (PV) systems perform a vital role in addressing the worldwide energy crisis and fulfilling the escalating energy demand. The variability in irradiance, temperature, and unpredictable weather conditions possess a direct impact on the productivity of PV systems. Furthermore, the existence of partially shaded conditions intensifies the complexity of PV systems, resulting in significant power degradation. These conditions present significant challenges for PV systems to achieve maximum power output and produce optimal energy. To address the prevailing challenges, this study introduces a maximum power point tracking (MPPT) control methodology utilizing a sand cat swarm optimizer (SCSO). This ingenious strategy adapts the sand cat hunting style. The investigation centers on optimizing energy harvesting in PV systems, with a specific emphasis on enhancing precision, rapid convergence, and minimizing oscillations. The suggested SCSO performance is evaluated under a variety of weather situations, including both instances of partially shaded and uniform irradiance. The SCSO results are juxtaposed with other existing bio-inspired algorithms, such as grey wolf optimization (GWO), particle swarm optimization (PSO), and tunicate swarm algorithm (TSA). The proposed SCSO technique achieves 99.94 % tracking accuracy on average and shows superior performance, with faster tracking response and less power oscillation. Moreover, the proposed SCSO generates significantly more energy than the rest compared algorithms. The performance of the suggested method is further validated through a hardware-based experimental assessment, demonstrating an optimal level of tracking performance.

THE SIGNIFICANCE OF BIOMASS IN ACHIEVING A GLOBAL BIOECONOMY

This manuscript explores the imperative role of biomass in shaping the global bioeconomy, necessitated by escalating energy demands and the consequent environmental challenges posed by fossil fuel dependency. This paper delineates the diverse forms of biomass — from lignocellulosic materials to organic waste and algae — each holding distinct chemical compositions and applications within the bioeconomy. Investigating biomass conversion technologies (i.e. thermochemical, biochemical and chemical) provides a comprehensive understanding of their merits and limitations in energy production and resource optimisation. Specifically, it delves into pyrolysis, gasification, hydrothermal liquefaction, torrefaction, anaerobic digestion and transesterification, elucidating their mechanisms and contributions to energy generation and biofuel production. Moreover, the study incorporates bibliometric analysis, depicting thematic clusters in biomass research and highlighting the evolving trends in its application within the bioeconomy. The primary focus of studies within the initial cluster revolves around utilising biomass for a global bioeconomy through thermochemical conversion methods. Overall, this review underscores the indispensable role of biomass as a renewable and adaptable resource, pivotal in steering the transition towards a sustainable bio-based economy amid global environmental and socio-economic challenges.

Eggshell membrane-derived electrocatalysts for water electrolysis

Green H2 (GH2) holds significant promise as a renewable energy resource, particularly in addressing the escalating energy demands sustainably. The imperative for economically viable GH2 technologies, primarily via water electrolysis, has spurred extensive research into suitable electrocatalytic materials. Eggshell membrane (ESM) is typically considered a biowaste material obtained from eggs, which are among the most widely consumed foods both domestically and industrially. Many countries legally require the effective treatment of ESM before disposal to prevent environmental contamination. Therefore, we propose upcycling ESM as an electrocatalytic support, forming transition metal-based active sites through chemical and thermal treatment, followed by doping highly reactive Fe sites electrochemically. ESM’s nanofibrous morphology and porous structure confer catalytic advantages. X-ray photoelectron spectroscopy analysis reveals that certain chemical functional groups in the ESM are involved in the spontaneous electrochemical charge transfer and the adsorption of metal ions, contributing to the formation of metal nanoparticles. Furthermore, various anionic chemical elements such as P, O, N, and S, which originate from intrinsic ESM, can participate in electrocatalysis. The Fe sites electrochemically induced on the Ni and Co nanoparticle surfaces in the ESMs demonstrate excellent electrocatalytic activity and durability toward the oxygen and hydrogen evolution reactions, respectively. This study provides a strategy to utilize ESM as an electrocatalytic material for the development of commercially viable electrocatalysts to produce GH2 by transforming biowaste into value-added materials. Moreover, it promotes the investigation of the (electro)chemical functionalities of biomaterials and the correlation between their functions and electrocatalytic activities.

Amide‐derived Norbornadienes: Towards Efficient Molecular Solar Thermal Systems in Polar Solvents

Solar energy harvesting is a promising alternative to the escalating energy demand. Among emerging technologies, MOlecular Solar Thermal (MOST) systems offer exciting avenues for solar fuel generation. However, their widespread application is partially hindered by the use of environmentally problematic and potentially hazardous organic non‐polar solvents, such as toluene. Addressing this challenge, we here developed a series of four norbornadienes (NBDs) featuring symmetric amide substituents via functionalization of the readily available diacid substituted NBD. These compounds exhibit enhanced solubility in greener solvents like ethanol, a significant advancement over non‐polar NBDs. Moreover, the reversible switching was demonstrated for three new NBDs through photoisomerization via UV‐light absorption and to form QC and reversible catalysis via a commercial heterogeneous gold‐based catalyst. By expanding the repertoire of environmentally benign solar fuel materials, this research contributes to the broader objective of sustainable energy generation and storage.

Sustainability considerations in bio-hydrogen from bio-algae with the aid of bio-algae cultivation and harvesting: Critical review

Abstract Microalgae present an enticing alternative to conventional fossil fuel-dependent technologies for producing hydrogen, offering an intriguing and sustainable energy source. Numerous strains of microalgae are under investigation for their capacity to generate hydrogen, alongside various techniques and breakthroughs being developed to optimize the process. However, significant hurdles must be addressed for commercial viability, including the high manufacturing costs and the necessity for efficient harvesting and sorting methods. This paper delves into several aspects concerning hydrogen synthesis in algae, encompassing microalgae anatomy and physiology, hydrogen synthesis via photosynthesis and dark fermentation, and the integration of microalgal hydrogen synthesis with other renewable energy sources. The potential for microalgal hydrogen generation is considered pivotal in transitioning toward a future reliant on more renewable and sustainable energy sources. This review aims to serve as a valuable resource for researchers, decision-makers, and anyone interested in the advancement of environmentally conscious energy technology. The primary objective of this research paper is to scrutinize the challenges, opportunities, and potential outcomes associated with eco-friendly bio-hydrogen production through algae. It evaluates the current technological hurdles facing bio-hydrogen synthesis from algae. Graphical abstract Highlights Interest in developing renewable fuels, such as hydrogen from biomass, has surged due to escalating energy demands and the imperative to curtail greenhouse gas emissions. Overview of bio-hydrogen production pathway, reactor designs, and configurations for bio-hydrogen production from bio-algae were explored. Environmental, social sustainability and economic feasibility have been reviewed. Discussion Will bio-hydrogen from bio-algae be a future renewable energy? Which is the best pathway to produce bio-hydrogen from bio-algae? Regarding greenhouse gas emissions, how does the generation of bio-hydrogen from bio-algae compare to conventional hydrogen production techniques? What difficulties lie in increasing the amount of bio-hydrogen produced by bio-algae to satisfy major energy demands?

TRNSYS Simulation of a Bi-Functional Solar-Thermal-Energy-Storage-Assisted Heat Pump System

The escalating energy demands in buildings, particularly for heating and cooling demands met by heat pumps, have placed a growing stress on energy resources. The bi-functional thermal diode tank (BTDT) is proposed as thermal energy storage to improve the heating and cooling performances of heat pumps in both summer and winter. The BTDT is an insulated water tank with a gravity heat pipe (GHP), which can harvest and store heat passively from sun radiation and the external environment during the daytime. In summer, it harvests and stores cold energy from the air and night sky during the daytime. The performance of the BTDT-assisted heat pump (BTDT-HP) system in Adelaide, Australia, during the 2021–2022 summer and winter seasons was evaluated by conducting a TRNSYS simulation. This study revealed that the BTDT-HP system outperformed the reference ASHP system, where up to 8% energy in heating and 39.75% energy in cooling could be saved. An overall reduction in the energy consumption of 18.89% was achieved. Increasing the BTDT volume and GHP panel area enabled the tank to store more thermal and cold energy across the winter and summer seasons, thereby improving the system’s performance. The maximum ESPs were found to be 31.6% and 41.2% for heating and cooling for the study case under optimal conditions. When the GHP panel area was fixed at 15 m2, the BTDT volume should be at least 28 m3 for the BTDT-HP system, boasting cooling and heating capacities of 40 kW and 43.2 kW, to achieve positive energy savings.

A Novel Sustainable and Self-Sufficient Biotechnological Strategy for Directly Transforming Sewage Sludge into High-Value Liquid Biochemicals.

Sewage sludge, as a carbon-rich byproduct of wastewater treatment, holds significant untapped potential as a renewable resource. Upcycling this troublesome waste stream represents great promise in addressing global escalating energy demands through its wide practice of biochemical recovery concurrently. Here, we propose a biotechnological concept to gain value-added liquid bioproducts from sewage sludge in a self-sufficient manner by directly transforming sludge into medium-chain fatty acids (MCFAs). Our findings suggest that yeast, a cheap and readily available commercial powder, would involve ethanol-type fermentation in chain elongation to achieve abundant MCFA production from sewage sludge using electron donors (i.e., ethanol) and acceptors (i.e., short-chain fatty acids) produced in situ. The enhanced abundance and transcriptional activity of genes related to key enzymes, such as butyryl-CoA dehydrogenase and alcohol dehydrogenase, affirm the robust capacity for the self-sustained production of MCFAs. This is indicative of an effective metabolic network established between yeast and anaerobic microorganisms within this innovative sludge fermentation framework. Furthermore, life cycle assessment and techno-economic analysis evidence the sustainability and economic competitiveness of this biotechnological strategy. Overall, this work provides insights into sewage sludge upgrading independent of additional carbon input, which can be applied in existing anaerobic sludge fermentation infrastructure as well as to develop new applications in a diverse range of industries.

Decentralized Smart Energy Management in Hybrid Microgrids: An Evaluation of Operational Modes, Resource Optimization, and Environmental Impacts in Nigeria

Escalating energy demands and climate change challenges necessitate the adaptation of renewable-based microgrid systems in the energy sector. The proposed work employs a robust Multi Agent System (MAS) technique to achieve efficient and automated control of the hybrid microgrid operation. The hybrid microgrid system incorporates Renewable Energy Sources (RES), a diesel generator, and a battery storage system. The operation of the hybrid microgrid consists of three distinct modes: islanded, transition to grid, and grid-oriented mode. The system’s performance is optimized by considering factors like climatic patterns, energy costs, connected source characteristics, and load demand. Different climatic scenarios are assessed for each mode of operation, where the best, extreme sunny, extreme cloudy, and worst climate conditions are considered for islanded mode; sunny and cloudy scenarios are considered for transition to grid mode as well as grid-feed and grid-tied modes are considered for grid-oriented operation of the microgrid. The simulation studies are performed using the MATLAB/Simulink R2021a environment. Furthermore, Particle Swarm Optimization (PSO) is implemented to optimize power allocation within the microgrid and enhance its cost-effectiveness. The optimization results demonstrate efficient utilization of available energy sources along with effective energy management facilitated by the MAS control system. The results emphasize the importance of adopting a MAS approach for achieving smart energy management through comprehensive analysis and integrating decentralized energy management techniques for optimal accommodation of distributed energy resources in hybrid microgrids

The crucial role of renewable energy in achieving the sustainable development goals for cleaner energy

The modern world is rapidly transforming into an interconnected global community, driven by escalating energy demands. Despite this evolution, Earth's resources remain finite. The growing need for energy, coupled with the imperative to address human development, well-being, and health, necessitates a robust response to climate change. A decisive shift towards renewable energy sources is crucial and must be sustainable to meet future energy demands. This study explores opportunities presented by renewable energy sources, focusing on solar, wind, geothermal, and hydrogen energy, alongside net-zero sustainability through carbon and methane capture. These sources enhance energy security, improve energy access, promote social and economic development, mitigate climate change, and reduce environmental and health impacts. However, challenges hinder the sustainable adoption of renewable energy, including market failures, limited access to information, the need for essential raw materials, and rising carbon emissions. To address these, the paper proposes measures and policy recommendations aimed at advancing the renewable energy agenda, reducing emissions, mitigating climate change, and ensuring a clean environment and sustainable energy for future generations.