Search Results (184)

Promoting the clean energy transition is crucial for environmental sustainability and public health. Utilizing data from the China Health and Nutrition Survey (CHNS) spanning 2006–2015, this study employs a Difference-in-Differences (DID) model, treating China’s West–East Gas Pipeline Project (WEGT) as a quasi-natural experiment to evaluate the causal impact of natural gas infrastructure expansion on residents’ health. The empirical results indicate that the WEGT significantly improved public health, reducing the probability of self-reported recent illness by approximately 8.2 percentage points. Heterogeneity analysis shows more pronounced effects among urban residents and the elderly. Mechanism analysis reveals that the infrastructure improves health primarily by optimizing household energy structures and reducing industrial pollution emissions. Furthermore, the “Coal-to-Gas” policy synergistically enhances these health benefits. Economic co-benefits analysis estimates that the project reduced individual annual medical expenditures by approximately 540 RMB and increased the probability of employment by 6.9%. These findings provide empirical evidence for deepening supply-side structural reforms in energy and support the realization of the United Nations Sustainable Development Goals (SDGs), specifically by demonstrating how resilient infrastructure (SDG 9) enables affordable clean energy (SDG 7), which in turn delivers good health and well-being (SDG 3). Full article

The present study investigates the potential of poplar (Populus spp.) biomass from phytoremediation plantations as a feedstock for downdraft fixed bed gasification. The biomass was characterized in terms of moisture, ash content, elemental composition (C, H, N, O), and calorific values (HHV and LHV), confirming its suitability for thermochemical conversion. Gasification tests yielded a volumetric syngas production of 1.79 Nm³ kg⁻¹ biomass with an average composition of H₂ 14.58 vol%, CO 16.68 vol%, and CH₄ 4.74 vol%, demonstrating energy content appropriate for both thermal and chemical applications. Alkali and alkaline earth metals (AAEM), particularly Ca (273 mg kg⁻¹) and Mg (731 mg kg⁻¹), naturally present enhanced tar reforming and promoted reactive gas formation, whereas heavy metals such as Cd (0.27 mg kg⁻¹), Pb (0.02 mg kg⁻¹), and Bi (0.01 mg kg⁻¹) were detected only in trace amounts, posing minimal environmental risk. The results indicate that poplar pruning residues from phytoremediation sites can be a renewable and sustainable energy resource, transforming a waste stream into a process input. In this perspective, the integration of soil remediation with syngas production constitutes a tangible model of circular economy, based on the efficient use of resources through the synergy between environmental remediation and the valorization and sustainable management of marginal biomass—i.e., pruning residues—generating environmental, energetic, and economic benefits along the entire value chain. Full article

Cyprus launched its Competitive Electricity Market on 1 October 2025, marking a historic transition from monopolistic to liberalized electricity trading. This paper presents a comprehensive analysis of the market’s first month of operation, evaluating technical performance, price dynamics, market structure, and identifying critical barriers to achieving competitive benefits. Analysis reveals technically successful operation of clearing mechanisms and settlement processes, but economically constrained performance driven by persistent structural limitations. The market exhibits extreme price volatility characteristic of isolated systems, ranging from zero to 500 EUR/MWh, with pronounced diurnal patterns reflecting solar generation dynamics. The monthly wholesale price averaged at 167.78 EUR/MWh. The market remains highly concentrated with only 17 participants, shallow liquidity, and heavy reliance on conventional generation (86%) despite installed renewable capacity exceeding 1000 MW. Critical infrastructure deficits including absent natural gas infrastructure, lack of utility-scale storage, electrical isolation, and incomplete smart metering deployment represent fundamental barriers to achieving EU Target Model objectives. Based on infrastructure deployment scenarios and international benchmarking, we suggest potential reductions in the wholesale price of 12.5% (base scenario) to 15% (optimistic scenario) by the end of 2027, dependent on timely natural gas commissioning, storage deployment, and regulatory reform. Policy recommendations address immediate regulatory actions, medium-term market development priorities, and critical infrastructure investments essential for transitioning from technically operational to economically beneficial market operation. This analysis contributes to understanding the challenges that small, isolated electricity markets face when implementing EU liberalization frameworks while highlighting policy interventions required for successful market maturation. Full article

This study investigates the evolution of China’s greenhouse gas (GHG) emissions from 1969 to 2022 by combining Bai–Perron structural break analysis with Environmental Kuznets Curve (EKC) estimation. Prior research often assumes that economic growth naturally leads to emissions stabilization; however, our results show that China’s emissions trajectory did not decline automatically with rising income. Instead, major turning points coincide with targeted policy interventions, particularly after 2012 under the Ecological Civilization framework. While some EKC models suggest an inverted-U shape, the predicted turning points exceed observed income levels, indicating that growth alone cannot account for the recent deceleration in emissions. Evidence points to strengthened regulatory enforcement, centralized environmental governance, and large-scale renewable energy deployment as factors associated with these changes. These findings challenge the notion of a self-driven environmental transition and underscore the pivotal role of state-led institutional reforms in China’s decarbonization process. Full article

This paper examines the impact of natural resource rents on the economic growth of Tunisia between 1990 and 2023, emphasizing the aspect of resource diversification. The annual time-series data extracted from the World Bank’s World Development Indicators were analyzed using the Autoregressive Distributed Lag model to outline both the short- and long-run dynamics. The results confirm the existence of a long-term relationship between economic growth and oil, natural gas, mineral, and forest rents. Among them, oil and forest rents have strong positive long-term impacts, whereas natural gas and mineral rents contribute relatively moderately due to the structural inefficiencies and absence of value-added activities in these sectors. It was also found that the labor force participation has been affecting growth adversely with continuous impacts, which are driven by skill mismatches, low productivity, and high unemployment, hence indicating structural labor market imbalance that weakens the growth effect of labor. On the other hand, capital formation is still one of the key drivers of long-term growth. The findings highlight the rationale for diversification of the economy, governance reforms, and sustainable management of resources. However, the study suffers from some limitations due to data availability and excluded institutional variables, apart from being narrowed to a single-country case study, which might affect the generalizability of the results. Future works could consider incorporating the indicators of governance, examining nonlinear effects, or expanding the analysis into a multi-country framework. Full article

Blue hydrogen technology, generated from natural gas through carbon capture and storage (CCS) technology, is a promising solution to mitigate greenhouse gas emissions and meet the growing demand for clean energy. To improve the sustainability of blue hydrogen, it is crucial to explore alternative feedstocks, production methods, and improve the efficiency and economics of carbon capture, storage, and utilization strategies. Two established technologies for hydrogen synthesis are Steam Methane Reforming (SMR) and Autothermal Reforming (ATR). The choice between SMR and ATR depends on project specifics, including the infrastructure, energy availability, environmental goals, and economic considerations. ATR-based facilities typically generate hydrogen at a lower cost than SMR-based facilities, except in cases where electricity prices are elevated or the facility has reduced capacity. Both SMR and ATR are methods used for hydrogen production from methane, but ATR offers an advantage in minimizing CO₂ emissions per unit of hydrogen generated due to its enhanced energy efficiency and unique process characteristics. ATR provides enhanced utility and flexibility regarding energy sources due to its autothermal characteristics, potentially facilitating integration with renewable energy sources. However, SMR is easier to run but may lack flexibility compared to ATR, necessitating meticulous management. Capital expenditures for SMR and ATR hydrogen reactors are similar at the lower end of the capacity spectrum, but when plant capacity exceeds this threshold, the capital costs of SMR-based hydrogen production surpass those of ATR-based facilities. The less profitably scaled-up SMR relative to the ATR reactor contributes to the cost disparity. Additionally, individual train capacity constraints for SMR, CO₂ removal units, and PSA units increase the expenses of the SMR-based hydrogen facility significantly. Full article

A transition from fossil fuels to renewable energy is underway to achieve net-zero emissions. The institutional arrangements in Indonesia’s energy transportation sector are crucial for various stakeholders involved in the energy transition. This study combines historical institutionalism with a multi-level perspective to analyze how policy formulation, critical junctures, and path dependence shape institutional changes toward sustainable mobility. The evolution of institutional arrangements can be categorized into three phases: the establishment of fuel-oil-based infrastructure and dependency (1970–2003); the diversification of cleaner fuels through compressed natural gas and biofuels (2004–2014); and the development of affordable and clean energy, focusing on biofuels and electrification (2015 to present). In parallel, a quantitative total cost of ownership analysis of vehicles using different fuel types demonstrates how institutional reforms, fiscal incentives, and regulatory support reshape the economic feasibility of low-carbon technologies. Landscape pressures—such as global decarbonization, fuel import dependence, and energy security challenges—interact with niche innovations, including biofuels, electric vehicles, and hybrid systems, to drive systemic transformation. The findings indicate that institutional changes, supported by quantitative economic evidence and technology diffusion, play a pivotal role in realigning Indonesia’s transport energy regime toward a more resilient, inclusive, and sustainable transition. Full article

The transition to low-carbon energy systems demands robust strategies that leverage existing fossil resources while integrating renewable technologies. In this work, a single-cycle Gaussian-based producibility model is developed to forecast natural gas production profiles, domestic consumption, export potential, hydrogen production and revenues, adaptive for untapped natural gas discoveries. Annual natural gas production is represented by a bell curve defined by peak year and maximum capacity, allowing flexible adaptation to different reserve sizes. The model integrates renewable energy adoption and steam–methane reforming to produce hydrogen, while tracking revenue streams from domestic sales, exports and hydrogen markets alongside carbon taxation. Applicability is demonstrated through a case study of Eastern Mediterranean gas discoveries, where combined reserves of 2399 bcm generate a production peak of 100 bcm/year in 2035 and deliver 40.71 billion kg of hydrogen by 2050, leaving 411.87 bcm of reserves. A focused Cyprus scenario with 411 bcm of reserves peaks at 10 bcm/year, produces 4.07 billion kg of hydrogen and retains 212.29 bcm of reserves. Cumulative revenues span from USD 84.37 billion under low hydrogen pricing to USD 247.29 billion regionally, while the Cyprus-focused case yields USD 1.79 billion to USD 18.08 billion. These results validate the model’s versatility for energy transition planning, enabling strategic insights into infrastructure deployment, market dynamics and resource management in gas-rich regions. Full article

Hydrogen-based technologies, prominently fuel cells, are emerging as strategic solutions for decarbonization. They offer an efficient and clean alternative to fossil fuels for electricity generation, making a tangible contribution to the European Green Deal climate objectives. The primary issue is the production and transportation of hydrogen. An on-site hydrogen production system that includes CO₂ capture could be a viable solution. The proposed power system integrates an internal combustion engine (ICE) with a steam methane reformer (SMR) equipped with a CO₂ capture and energy storage system to produce “blue hydrogen”. The hydrogen fuels a high-temperature polymer electrolyte membrane (HT-PEM) fuel cell. A battery pack, incorporated into the system, manages rapid fluctuations in electrical load, ensuring stability and continuity of supply and enabling the fuel cell to operate at a fixed point under nominal conditions. This hybrid system utilizes natural gas as its primary source, reducing climate-altering emissions and representing an efficient and sustainable solution. The simulation was conducted in two distinct environments: Thermoflex code for the integration of the engine, reformer, and CO₂ capture system; and Matlab/Simulink for fuel cell and battery pack sizing and dynamic system behavior analysis in response to user-demanded load variations, with particular attention to energy flow management within the simulated electrical grid. The main results show an overall efficiency of the power system of 39.9% with a 33.5% reduction in CO₂ emissions compared to traditional systems based solely on internal combustion engines. Full article

The integration of renewable energy into industrial processes is crucial for reducing the carbon footprint of conventional hydrogen production. This work presents detailed design, optical–thermal simulation, and performance analysis of a solar parabolic dish (SPD) system for supplying high-temperature steam to a Steam Methane Reforming (SMR) plant. A 5 m diameter dish with a focal length of 3 m was designed and optimized using COMSOL Multiphysics (version 6.2) and MATLAB (version R2023a). Optical ray tracing confirmed a geometric concentration ratio of 896×, effectively focusing solar irradiation onto a helical cavity receiver. Thermal–fluid simulations demonstrated the system’s capability to superheat steam to 551 °C at a mass flow rate of 0.0051 kg/s, effectively meeting the stringent thermal requirements for SMR. The optimized SPD system, with a 5 m dish diameter and 3 m focal length, was designed to supply 10% of the total process heat (≈180 GJ/day). This contribution reduces natural gas consumption and leads to annual fuel savings of approximately 141,000 SAR (Saudi Riyal), along with a substantial reduction in CO₂ emissions. These quantitative results confirm the SPD as both a technically reliable and economically attractive solution for sustainable blue hydrogen production. Full article

Second-, third-, and fourth-generation biofuels represent an important response to the challenges of clean energy supply and climate change. In this context, the Horizon 2020 “TO-SYN-FUEL” project aimed to produce advanced biofuels together with phosphorus from municipal wastewater sludge through a combination of technologies including a Thermo-Catalytic Reforming system, Pressure Swing Adsorption for hydrogen separation, Hydrodeoxygenation, and biochar gasification for phosphorous recovery. This article presents the environmental performance results of the demonstrator installed in Hohenberg (Germany), with a capacity of 500 kg per hour of dried sewage sludge. In addition, four alternative scenarios are assessed, differing in the source of additional thermal energy used for sludge drying: natural gas, biogas, heat pump, and a hybrid solar greenhouse. The environmental performance of these scenarios is then compared with that of conventional fuel. The comparative study of these scenarios demonstrates that the biofuel obtained through wood gasification complies with the Renewable Energy Directive, while natural gas remains the least sustainable option. Heat pumps, biogas, and greenhouse drying emerge as promising alternatives to align biofuel production with EU sustainability targets. Phosphorus recovery from sewage sludge ash proves essential for compliance, offering clear environmental benefits. Although sewage sludge is challenging due to its high water content, it represents a valuable feedstock whose sustainable management can enhance both energy recovery and nutrient recycling. Full article

Hydrogen, as a clean energy source, has enormous potential in addressing global climate change and energy security challenges. This paper discusses different hydrogen production methodologies (steam methane reforming and water electrolysis), focusing on the electrolysis process as the most promising method for industrial-scale hydrogen generation. The review delved into three main electrolysis methods, including alkaline water electrolysis, proton exchange membrane electrolysis, and anion exchange membrane electrolysis cells. Also, the production of hydrogen as a by-product by means of membrane cells and mercury cells. The process of reforming natural gas (mainly methane) using steam is currently the predominant technique, comprising approximately 96% of the world’s hydrogen synthesis. However, it is carbon intensive and therefore not sustainable over time. Water, as a renewable resource, carbon-free and rich in hydrogen (11.11%), offers one of the best solutions to replace hydrogen production from fossil fuels by decomposing water. This article highlights the fundamental principles of electrolysis, recent membrane studies, and operating parameters for hydrogen production. The study also shows the amount of pollutant emissions (g of CO₂/g of H₂) associated with a hydrogen color attribute. The integration of water electrolysis with renewable energy sources constitutes an efficient and sustainable strategy in the production of green hydrogen, minimizing environmental impact and optimizing the use of clean energy resources. Full article

Natural gas (NG) engine catalysts face unique challenges in emission control due to their distinct raw emission characteristics. This study investigates the exhaust conversion and by-product generation of a Palladium-based catalyst of an NG engine through small-sample catalyst experiments, mainly focusing on the effect of feed gas composition on the conversion efficiency and N₂O/NH₃ emissions. Results show that N₂O is generated via NO reduction by H₂ (80~275 °C) and CO (275~400 °C) in the temperature range of 80~400 °C. NH₃ generation occurs at 175~550 °C, mainly via NO reduction by H₂ (supplied from the water–gas shift (WGS) reaction) and CO below 425 °C and exclusively by H₂ (supplied from the steam reforming (SR) reaction) above 425 °C. An increase (0.9705~1.0176) in lambda enhances CO and CH₄ conversion while reducing N₂O and NH₃ emissions, but it inhibits NO conversion and promotes NO₂ formation. A lambda of 0.9941 achieves high conversion efficiency (≥90%) for CO, CH₄, and NO, with reduced N₂O and zero NH₃ emissions. An increase in H₂O (8~16%) accelerates the WGS and SR reactions, improving pollutant conversion. However, it aggravates N₂O and NH₃ emissions, with peak levels rising by 54% and 31%, respectively. Increased H₂ (500~1500 ppm) preferentially consumes NO and reversely shifts the equilibrium of the WGS and SR reactions, reducing CO and CH₄ conversion while improving NO conversion. And it promotes N₂O selectivity at high temperature and NH₃ selectivity at low temperature and peak emissions, with peak concentrations increasing by 58% and 15%, respectively. These findings reveal the by-product formation mechanism in the catalyst, providing valuable insights for the emission control of NG-fueled engines. Full article

An advanced gasification module (AGM) for green hydrogen production involves a small-scale biomass gasification process owing to the low energy density of biomass. Therefore, significant heat loss and the endothermic nature of gasification system require additional fossil fuel heat, increasing CO₂ emissions. This study focuses on bioenergy conversion with carbon capture and utilization (BECCU), where carbon-neutral CO₂ from biomass gasification is captured and reused as a gasifying agent to reduce the greenhouse gas intensity of green hydrogen. BECCU is expected to achieve negative emissions and enhance gasification efficiency by promoting conversion of char and tar through CO₂ gasification. To evaluate the effectiveness of BECCU in the AGM, we conducted a sensitivity analysis of the reformer temperature and S/C ratio using process simulation combined with life cycle assessment. In both sensitivity analyses, the GWP for CO₂ capture was lower compared with conventional conditions, considering recovered CO₂ from purification and the additional steam generated through heat recovery. This suggests improved hydrogen yields from enhanced char and tar conversion. Consequently, the GWP was reduced by more than 50%, demonstrating BECCU’s effectiveness in the AGM. This represents a step toward operating biomass gasification systems with lower environmental impact and contributing to sustainable energy production. Full article

Biomass gasification represents a pivotal technology for sustainable energy and chemical production, yet its efficiency and product quality are critically dependent on catalyst performance. This comprehensive review systematically synthesizes recent advancements in catalyst design, mechanistic insights, and process integration in biomass gasification. Firstly, it details the development and performance of catalysts in diverse categories, including metal-based catalysts, Ca-based catalysts, natural mineral catalysts, composite/supported catalysts, and emerging waste-derived catalysts. Secondly, this review delves into the fundamental catalytic reaction mechanisms governing key processes such as tar cracking/reforming, water–gas shift, and methane reforming. It further explores sophisticated strategies for catalyst structure optimization, focusing on pore structure/surface area control, strong metal–support interactions (SMSIs), alloying effects, nanodispersion, and crystal phase design. The critical challenges of catalyst deactivation mechanisms and the corresponding activation, regeneration strategies, and post-regeneration performance evaluation are thoroughly discussed. Thirdly, this review addresses the crucial integration of zero CO₂ emission concepts, covering in situ CO₂ adsorption/conversion, carbon capture and storage (CCS) integration, catalytic CO₂ reduction/valorization, multi-energy system synergy, and environmental impact/life cycle analysis (LCA). By synthesizing cutting-edge research, this review identifies key knowledge gaps and outlines future research directions towards designing robust, cost-effective, and environmentally benign catalysts for next-generation, carbon-neutral biomass gasification systems. Full article