Sustainable Energy Research Articles

A hybrid piezoelectric-electromagnetic body energy harvester: Design and experiment validation

Abstract The rapid advancement of electronic devices and wireless sensors has heightened the demand for energy sustainability and portable power solutions. This paper proposes a hybrid piezoelectric-electromagnetic energy harvesting (HP-EEH) structure designed to enhance the efficiency of kinetic energy conversion within the human body. Firstly, the structure and principle of the energy capture device are introduced, and the electromechanical coupling model of the energy harvester is derived using Hamilton's principle. Furthermore, the system is numerically simulated, and the voltage output characteristics of the piezoelectric unit and the electromagnetic unit are analyzed by using the finite element analysis software. Finally, the experimental setup of the (HP-EEH) is constructed, and the voltage output characteristics are tested for different swinging angles and positions. The results show that two parts of energy can be captured simultaneously under ultra-low-frequency motion conditions. At a swing angle of 50 degrees, the piezoelectric and electromagnetic units achieved maximum output power values of 14.96 µW at 0.8 Hz and 10.4 µW at 1.2 Hz, respectively. Incorporating the output power of the electromagnetic unit aims to address the power consumption requirements of low-power devices better.

IoT-enabled smart cities towards green energy systems: a review

<span>Integration of internet of things (IoT) in smart city management to improve various functions and living standards due to increasing population growth has dramatically evolved ubiquitous and essential services at various stages of urbanization. Hence, smart cities need to be eco-friendly by improving various sectors like education, health, and transport to provide an urban and sustainable quality of life through solving complicated green energy networks, controlling toxic pollution risks, and public safety. Linking optimized green energy systems with the production and automation of advanced applications is crucial to compose implementation strategies for smart city services. This paper aims to conduct a review on eco-friendly plans and infrastructure of IoT-enabled smart cities by exploiting green energy approaches. This study performs critical observations, ideas, and analyses of recent research in the context of our mentioned research theme. This paper points out the technical and functional challenges of an optimal performance-based green IoT-enabled smart city infrastructure. In this sense, this study organizes observations of relevant initiatives, technologies, and experiences in IoT-enabled smart cities, as well as how to embed it with green energy. Moreover, it can provide significant directions to intellectuals and authorities to develop IoT-enabled smart city applications for prospective research.</span>

Energy Poverty Alleviation in the Era of Energy Transition—Case Study of Poland and Sweden

The energy transition, aimed at significantly reducing greenhouse gas emissions to combat climate change, presents both opportunities and challenges in addressing energy poverty. This article explores the differing approaches of Poland and Sweden in energy poverty alleviation within the context of this transition. Poland, with its historical dependence on coal, faces considerable obstacles as it seeks to shift towards cleaner energy sources while minimizing the impact on vulnerable populations. Conversely, Sweden, supported by its advanced energy infrastructure and strong welfare systems, has implemented effective strategies that have largely mitigated energy poverty, though challenges persist for low-income households, especially in rural areas. The article delves into the definitions, drivers, and alleviation strategies of energy poverty in both countries. Through a comprehensive literature review and the analysis of key initiatives such as Poland’s Clean Air Program and Sweden’s Warm Rent scheme, the study underscores the potential for policy interventions to address energy poverty. It concludes with recommendations on how both countries can further reduce energy poverty, highlighting the critical role of energy efficiency, social support systems, and the integration of renewable energy in achieving a fair and equitable energy transition.

A new carbon-negative hydrogen production cycle for better sustainability

Carbon dioxide removal is considered by many as an essential piece to achieve global net zero targets which was also mentioned by the third working group of Intergovernmental Panel on Climate Change. On top of this, green hydrogen is badly needed to achive carbon-free society long-term sustainability. This study proposes a new five-step sodium hydroxide thermochemical cycle for simultaneous hydrogen production and carbon dioxide removal, which is driven by the heat at least 400 °C. The proposed integrated cycle can be driven by clean energy sources that can be utilized to generate heat at required temperatures. The proposed system is designed and analyzed by using energy and exergy approaches of thermodynamics. A case study is also developed in order to understand the effects of changing parameters on system performance. A thermochemical hydrogen production cycle is designed with an unequilibrium reaction where the respective heat capacity calculation models are employed. According to the calculations, more than half of the energy content of process heat can be converted into hydrogen, where maximum energy and exergy efficiencies of the thermochemical cycle are found as 50.05% and 76.61% when the separation reaction is carried out at 400 °C. According to the case study results, a parabolic trough collector type concentrated solar energy system with 295 kW of heat sink capacity, can generate 5216.65 kg of hydrogen and capture 19,991.97 kg of carbon dioxide in a location where 1500.11 kWh of solar energy is reached per m2 of area in a typical year.

Article: Redefining Global Trade: The Interplay of Geopolitics, Economic Resilience, and Sustainability?

This paper explores the shifting dynamics of global trade amid rising geopolitical tensions between the United States, the European Union, and China. It traces the evolution from post-World War II American-led globalization to hyperglobalization, where China emerged as a global manufacturing powerhouse. While hyperglobalization spurred economic growth and lowered consumer prices, it also led to job losses, income inequality, and environmental degradation in developed economies.The COVID-19 pandemic and the ongoing US-China trade conflict have accelerated a shift towards economic resilience and national security. The US has responded by decoupling from China, particularly in critical sectors like technology and clean energy, viewing economic policy as integral to national security. Meanwhile, the EU, though aligned with the US in geopolitical concerns, remains economically dependent on China and has adopted a more regulatory approach. The EU seeks to balance its economic ties with China by leveraging trade regulations, such as the Carbon Border Adjustment Mechanism (CBAM) and the Corporate Sustainability Reporting Directive (CSRD), to encourage Chinese investment while promoting higher environmental and social standards.The paper also examines the increasing influence of environmental policies on trade, noting how both the US and EU are integrating sustainability into their trade frameworks. However, this trend raises concerns about the potential for environmental regulations to become trade barriers, further complicating international relations.

The contribution of green technological innovation, clean energy, and oil rents in improving the load capacity factor and achieving SDG13 in Saudi Arabia

This research aims to assess the effects of green technological innovation, renewable energy sources, and oil rents on the load capacity factor in Saudi Arabia from 1988 to 2021. The primary conclusions can be outlined as follows. The combined cointegration and Saikkonen-Lütkepohl cointegration tests reveal long-run relationships between the load capacity factor and the explanatory variables at the 1% significance level. In comparison, the Phillips-Ouliaris test shows evidence of cointegration only at 10%. Moreover, the quantile regression indicates that oil rents adversely impact environmental quality; however, they remain contingent upon environmental conditions. A 1% increase in oil rents results in a decline in environmental quality by 0.025% under poor conditions, 0.036% under moderate/normal conditions, and 0.108% under good conditions. On the contrary, renewable energy consumption and green technological innovation improve environmental quality, irrespective of the prevailing environmental conditions. However, the environmental impacts of renewable energy consumption exceed those of green technological innovation. Results show that a 1% increase in renewable energy consumption leads to a 0.052-0.253% improvement in environmental quality, whereas a 1% increase in green technological innovation results only in a 0.017-0.047% improvement. Finally, population and GDP per capita exert negative and positive implications on the load capacity factor, respectively, while energy intensity has no significant environmental effects. The research findings provide significant insights and suggest policy recommendations to address climate change and meet the targets set out in SDG13.

Article: Green Regionalism: US Strategies to Ensure Secure and Reliable Supplies of Critical Minerals

Critical Minerals are essential constituents for numerous modern technologies from computers, and modern cars to household appliances. Most critical minerals are also key inputs in technologies that are crucial for clean energy transitions such as batteries, electric vehicles (EV), wind turbines, solar panels etc. Global trends indicate that the race for ensuring a secure and reliable supply of critical minerals is being furthered through industrial policy, domestic regulations as well as international economic law instruments. More recently these three aspects have been characterized by increasing securitization as seen through attempts to friendshore and reshore supply chains and capacities. This paper peruses the recent Critical Material Transparency and Reporting of Advanced Clean Energy (Critical Material TRACE) Bill which focuses on implementing a digital identifier system for advanced energy systems including batteries and battery components. The paper looks at the bill in connection with other initiatives aimed at creating United State (US) led critical mineral value chains. These include industrial policy measures including the Inflation Reduction Act (IRA) as well as international initiatives such as the Mineral Security Partnership (MSP) and the Indo-Pacific Economic Framework (IPEF) inter alia. In our examination, the focus is on analysing the progress made under the US-led MSP and the potential coverage and implication of the Critical Material TRACE Bill. We also examine if such steps by the US further promote green regionalism or are necessary to break the dominance of a few countries (mainly China) in leading the critical minerals supply chain.

New Trends in Green Projects Aimed at Clean Energy: An Analysis of the Scientific Literature

New Trends in Green Projects Aimed at Clean Energy: An Analysis of the Scientific Literature

Renewable Energy in Nepal: Current State and Future Outlook

Nepal’s energy mix is predominantly based on traditional and inefficient biomass and fossil fuels. As a result, there is a notable prevalence of energy scarcity in the country. Within the literature, there exists a lack of a comprehensive review of the potential of renewable energy in the country while the relatively less contribution of renewable energy resources, making the country more vulnerable to adopt a more carbon-intensive energy policy. Consequently, in this study, we conduct a thorough review of existing literature to provide a comprehensive assessment of the current status of renewable energy and the energy mix in Nepal. We also discussed the potential for the country to transition to a sustainable energy system. This review analysis exclusively focused on scholarly articles and research reports that specifically addressed the topic of renewable energy in Nepal. Despite the rapid decline in the cost of solar photovoltaics, Nepal’s renewable energy share currently stands at only 3.2%. This paper argues that Nepal needs proactive and favorable strategies and policies to effectively implement clean energy, based on the given premises and the country’s aspirations for sustainable energy. This involves a substantial amount of solar power production combined with battery storage, supplemented by storage methods such as off-river pumping hydropower technology. The study emphasizes the significance of renewable energy in achieving the United Nations’ Sustainable Development Goals (SDGs). This review also emphasizes the obstacles in the advancement of Nepal’s renewable energy industry and offers suitable policy suggestions to address these obstacles, hence facilitating a sustainable shift in energy.

Renewable energy in sustainable cities: Challenges and opportunities by the case study of Nusantara Capital City (IKN)

Indonesia's future IKN capital might be sustainable, low-carbon, and climate-resilient. The Low Emissions Analysis Platform (LEAP) simulates energy efficiency in various demand sectors, renewable energy, and sustainable transportation solutions. Sustainable cars, such as renewable-energy-powered electric and green hydrogen-powered vehicles, can reduce energy consumption by 43% in 2045 and 33% in 2060, respectively, compared to BAU. GHG emissions per capita will drop 70% in 2045 and 63% in 2060. In the net-zero emission (NZE) scenario, IKN can reach 100% green energy by 2045 with a 4.4 GW solar power plant, a 0.92 GWh BESS, and a full load hour capability of 4 hours. We will use 1.1 GW of hydropower and 143 MW of wind power by 2045. In 2060, hydropower will be 2.8 GW, wind power will be 184 MW, and solar power will be 8 GW with 1.6 GWh of BESS. Lack of legislation, technical expertise, high prices, inadequate grid infrastructure, and insufficient renewable electricity restrict BESS use in Indonesia. Solar energy installation requirements, subsidies, and off-grid project incentives can all help ease BESS use. Forecasts predict 0.53 GW of rooftop solar PV capacity by 2045 and 3.35 GW by 2060. Net metering and solar tariffs boost rooftop solar system profitability. One ton of green hydrogen production requires 55.7 MWh from a solar power plant. Solar power plant capacity will rise to 0.49 GW by 2045, producing 19,359 tons of green hydrogen, and almost quintuple to 89,594 tons by 2060. Hydrogen generation, storage, transit, and distribution require specific infrastructure due to high capital costs and a lack of networks, yet interest in them is growing.

Strategic Influence in Focus: Assessing the Roles of Defense Expenditures, Foreign Capital, Political Stability, and Energy Sustainability in Geopolitical Dynamics

Strategic Influence in Focus: Assessing the Roles of Defense Expenditures, Foreign Capital, Political Stability, and Energy Sustainability in Geopolitical Dynamics

SUBSTITUTION BETWEEN CLEAN AND DIRTY ENERGY WITH BIASED TECHNICAL CHANGE

AbstractThe elasticity of substitution between clean and dirty energy lies at the center of leading economic analyses of climate policy. Despite the importance, empirical assessments of this key parameter remain scarce. This article estimates the clean‐dirty elasticity of substitution using data on French manufacturing firms. Using the elasticity estimates, I then measure the bias in technical change at the firm level and find that technical change was largely biased toward dirty energy, despite a recent shift toward clean technologies. Finally, I recover the aggregate elasticity that combines substitution within firms and reallocation across firms from the micro elasticity estimates.

Investigations of the Impact of Geothermal Water Reinjection on Water-Rock Interaction through Laboratory Experiments and Numerical Simulations

In the quest for sustainable geothermal energy production, the adoption of geothermal reinjection technology has become a crucial element in the development of geothermal resources. However, the processes of injection and extraction can lead to interactions between water and rock within the geothermal reservoir, resulting in pore blockage. This study focuses on the Kaifeng Zhenyu Garden geothermal field as a case study to examine the water-rock interactions that occur during geothermal reinjection, as well as the subsequent changes in mineral composition and porosity within the reservoir. The findings reveal that the primary minerals undergoing dissolution are dolomite and feldspar, with the precipitation of calcite and clay minerals following suit. Additionally, results from field simulations corroborate that dolomite and feldspar are the main minerals dissolving, accompanied by the precipitation of calcite and illite. Notably, significant changes in mineral dissolution and precipitation near the geothermal well have led to a slight reduction in the reservoir's porosity. This investigation provides valuable insights into the water-rock interactions involved in geothermal reinjection processes across various geothermal fields.

Novel Two-dimensional Tellurophosphates: Visible Light Photocatalysts for Water Splitting and Carbon Dioxide Reduction

Exploring efficient two-dimensional (2D) photocatalysts for solar-driven water splitting into hydrogen and oxygen is crucial for sustainable hydrogen energy production. In this study, we investigated the suitability of novel 2D tellurophosphates M2P2Te6 (M=Mg, Ca, Sr, Ba, Ra) for photocatalytic overall water splitting using density functional theory (DFT) approach. The stability of tellurophosphates was assessed based on formation energies, phonon dispersions, ab initio molecular dynamics, and elastic modulus results. These monolayers have desirable direct bandgaps (∼1.6 – 2.2 eV) for efficient light absorption, and their valence and conduction bands ideally straddle both the oxidation and reduction potential of water along with the ability to reduce CO2 to hydrocarbons or carbonaceous products. Moreover, Gibbs free energies of Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) of tellurophosphate monolayers are also computed and display that these monolayers are viable photocatalysts under the influence of applied external potential. The tellurophosphates monolayers show strong optical absorption, with an absorption coefficient reaching up to 105 cm-1, across both the visible and UV regions of the solar spectrum, accompanied by high carrier mobility (order of 103 cm2 V-1s-1). The predicted solar-to-hydrogen efficiency of all monolayers exceeds 12%, fulfilling the criteria for commercial and economic viability in solar hydrogen production. The theoretical findings of current study imply that novel 2D tellurophosphate monolayers are promising candidates for optoelectronics, especially as photocatalysts for overall water splitting and CO2 reduction.

Core-shell Cu7S4@PDA nanoboxes as a novel cathode for aluminum batteries

Battery energy storage technology is key to unlocking green renewable power's full potential. Cathode material is a key factor affecting the performance of aluminum batteries (ABs). In this paper, a novel core-shell Cu7S4@PDA nanobox cathode material for ABs was designed and prepared by a reasonable method. At 0.2 A/g, the Cu7S4@PDA nanoboxes can provide a reversible capacity of 142 mAh/g after 100 cycles, and the coulombic efficiency (CE) of almost all cycles is maintained around 100 %. Even at 3 A/g, Cu7S4@PDA can deliver a capacity of 68 mAh/g. The results show that PDA coating reduces the irreversible dissolution of S in Cu7S4, prevents the pulverization and agglomeration of Cu7S4, and improves its structural stability and conductivity.

Role of Institutional Quality and Financial Developments in Realizing Clean Energy Legislation in Indonesia

Role of Institutional Quality and Financial Developments in Realizing Clean Energy Legislation in Indonesia

Cooperative S-S coupling and H2 production from photocatalytic dehydrogenation of thiols over ReSe2/ZnIn2S4 heterostructure

Photocatalytic anaerobic dehydrogenation provides a new avenue to cooperatively produce clean fuels and fine chemicals, while minimizing waste discharge and reducing environmental impact. Here, we demonstrate an efficient co-production of disulfides and H2 via photocatalytic S-S dehydrogenation of thiols using a two-dimensional (2D) heterostructure of ultrathin ZnIn2S4 (ZIS) nanosheets decorated with dispersed (1T phase) ReSe2 nanoparticles. Experimental characterizations and DFT calculations reveal that integrating ReSe2 with ZIS leads to the formation of a robust internal electric field (IEF) within the ReSe2/ZIS heterostructure. The distorted 1T phase ReSe2 with abundant active Se sites and a high Fermi level induces downward band bending of ZIS at the interface, which promotes charge separation and expedites H2 evolution. Moreover, the introduction of ReSe2 provides more adsorptive sites, increasing the concentration of reactants on the catalyst surface. This enhancement fosters surface interactions between the catalyst and p-toluenethiol (PTT), ultimately accelerating the reaction rate. The optimal H2 and S-S coupling p-tolyl disulfide (PTD) production rates of the 5 wt% ReSe2/ZIS composite reach 2275 and 2303 µmol g−1h−1, respectively, approximately 5 times greater than those of blank ZIS. Importantly, the selectivity of PTD reaches 98.4 %. This visible-light-driven dehydrogenation process aligns with the principles and objectives of green chemistry, realizing high atom economy without generating byproducts. It is anticipated to open new possibilities for sustainable and environmentally friendly routes for synthesizing high-value chemicals and producing clean energy.

Assessing the Role of Sharia-Compliant Investments in Promoting Clean Energy and Sustainable Economic Development: A Study of Asia’s Financial and Renewable Energy Sectors

Assessing the Role of Sharia-Compliant Investments in Promoting Clean Energy and Sustainable Economic Development: A Study of Asia’s Financial and Renewable Energy Sectors

Corporate Tax Planning: Making Sense of Canada's Clean Energy Investment Tax Credits

Corporate Tax Planning: Making Sense of Canada's Clean Energy Investment Tax Credits

Enhancing Bulb Turbine Performance Assessing Air Injection for Vibration Mitigation and Hydrofoil Cavitation

Small hydro technology is playing a crucial role in advancing sustainable, clean energy policies as part of the global hydro development strategy. Its contribution to social and economic development is becoming more prominent, particularly in ensuring electricity access for rural communities and supporting industrial expansion. The main causes of bulb turbine failures under high operating conditions are frequently attributed to variations in pressure in the draft tubes, which are aggravated when a spinning vortex rope is formed under load operation. Different fluid injection techniques, namely compressed air and water jet injection, address these issues and reduce the negative results of cavitation. The investigation covers the flow visualization on the suction side of a single hydrofoil utilizing a cavitation tunnel and a bulb turbine. This study assesses the effectiveness of compressed air injection in reducing vibration generated by cavitation in bulb turbines. Positive results of the experimental studies suggest a decrease in noise and vibration by air injection that prevents oscillations of the vortex rope. This research also considers how the hydrofoil design of bulb runner blades influences flow characteristics. Hence, it provides knowledge on cavitation structures in diverse cavitation numbers. Different studies that compare the original and modified hydrofoil designs reveal remarkable improvements that may be due to changes in the key parameters of the hydrofoil, such as later cavitation initiation and reduced intensity. To obtain the optimal output of a bulb turbine by considering air injection for vibration reduction and hydrofoil design changes to limit the negative effect of cavitation, the Reynolds number and cavitation number are to be defined. This multidisciplinary approach possesses enormous potential to increase the reliability and efficiency of bulb turbines in challenging operating conditions.