Long-term Energy Research Articles

Lattice matching strategy in Cu-based oxides for large-scale and long-term thermochemical energy storage

Redox-active metal oxides, particularly Cu-based oxide, are noteworthy for their economic feasibility and potential as a recyclable, zero-carbon energy source. These materials are poised to serve as a sustainable solution for large-scale and long-term thermochemical energy storage (TCES), thereby mitigating the intermittency challenges inherent in renewable energy systems. However, a significant impediment to their performance is the materials sintering at elevated temperatures, which precipitate a decline in cyclic reversibility, often manifesting even within the initial cycle of operation. To counteract this limitation, we proposed an innovative approach that leverages the concept of lattice matching, augmented by the incorporation of cigarette butts in the synthesis process to fabricate a Cu-Ce heterogeneous interface. This matched lattice preserved the integrity of the TCES material's porous architecture. Additionally, the lattice oxygen within this composite exhibits a transferability. Even after a prolonged period of two years under ambient air conditions, the TCES material retains the capacity to discharge a remarkable 99.4 % of its adsorbed energy. Furthermore, over the course of 600 cycles, the system's stability is remarkably preserved at 98–100 %, and reversible loss of pure CuO is ∼40 % within the initial cycle. Given these attributes, this TCES material emerges as a promising candidate for industrial applications.

Combined cycle gas turbine (CCGT) plants utilizing methane-hydrogen blends represent a significant element in Australia’s journey toward achieving net-zero emissions

To deliver 570 TWh of dispatchable electricity to the grid in Australia, it is necessary to build up wind and solar photovoltaic power plants generating capacity of 325 GW, and a long-term hydrogen energy storage system comprising 50–150 GW of electrolyzers, 50 TWh of hydrogen storage, and 165 GW of hydrogen power generation. While the addition of other renewable energy producers and energy storage technologies effective on shorter scales are certainly welcome and positively impact the above demand, the inclusion of inter-annual variability and safety negatively impacts these numbers. Fuel cells are currently less advanced compared to electrolyzers and hydrogen storage in salt caverns. Expanding hydrogen power generation will require exploring additional opportunities. Here we advocate for methane-hydrogen Combined Cycle Gas Turbine (CCGT) plants. Their adaptability to effortlessly integrate methane and green hydrogen mixtures positions them as a key player in the evolution toward net zero. This transition will be complete once a fully established wind and solar photovoltaic generation, coupled with an efficient hydrogen energy storage system, is in place. Notably, these CCGT plants consistently yield the lowest Life Cycle Analysis (LCA) carbon dioxide (CO2) emissions during the grid’s progression toward net zero.

Application of hydrogen storage in polygeneration microgrids: Case study of wind microgrid in India

Renewable energy based stand-alone microgrids are highly promising to supply electricity to isolated communities and remote locations. However, both buffer and long-term energy storage are essential due to the highly intermittent nature of renewable sources. By employing hydrogen energy storage with fuel cell and electrolyser in these microgrids, multiple outputs such as electricity, heat, water, and fuel, can be achieved. Design, development and optimization of efficient energy storage system remain a key challenge for the stand-alone microgrid technology. One must ensure that the microgrid satisfies the required electric load but is not over-designed, which is achieved by limiting the two performance parameters i.e., unmet electrical load fraction and excess electricity fraction. The capacities of wind turbine, electrolyser and hydrogen storage are optimized corresponding to the limiting values of unmet electrical load (fUL) and excess electricity (fEX) below 10 %. For the location of Ladakh which has rich availability of wind resource, the optimum size of microgrid is observed to be smallest as WT-20 kW, El-20 kW, H2-15 kg with fUL and fEX as 6.4 % and 8.9 % respectively. The Levelised Cost of Energy (LCOE) is also minimum as 0.89 $/kWh for the location of Ladakh. The distribution of wind resource has significant impact on the size of hydrogen storage. Uniform wind energy with higher velocity round the year reduces the capacity of hydrogen energy storage. Kanyakumari has non-uniform wind resource across different months of the year corresponding to which the capacity of H2 storage is as high as 370 kg.

Spatial national multi-period long-term energy and carbon planning scenarios in Ecuador’s electric system

The Republic of Ecuador is developing a comprehensive plan to meet the increasing residential, industrial, and commercial energy demands. With a population of 17.08 million in 2018, the country is experiencing an annual average energy growth of approximately 7.13% until 2027. This research aims to model the incorporation of new and proposed power plants strategically planned to cater to the expanding demand needs. Ensuring that our existing energy infrastructure can adequately meet the current and growing needs of the residential, commercial, and industrial sectors should be made possible. In this paper, we present several hypotheses that need to be made to identify the potential demands for residential, industrial, and commercial requirements, making it more accessible to build new facilities that use renewable energy. Traditional and unconventional renewable energy sources, such as hydro-power, wind, and solar power, are being explored to generate electricity. The research employs quantitative methodology, beginning with gathering information and a detailed data analysis. Subsequently, a scenario-based model will examine the impact on energy demand and supply from 2020 to 2035. The results show that the Santiago hydroelectric project is becoming essential for the country’s energy development and that the current national power system will only be able to supply the electricity demand when the industrial city of Posorja is being developed. We suggest that to maintain Ecuador’s electricity trade balance as an electricity exporter, we continue with the energy investment plans currently issued by the Ministry of Energy and Mines. This study is relevant for establishing global financing arrangements involving the public and private sectors. In doing so, we can meet our hypothetical scenarios, ensuring that all energy needs are met by 2035. This will involve developing a robust national grid system with sufficient reserve capacity, meeting residential and projected commercial and industrial demand.

Promoting the Renewable Energy Zones by implementing the photovoltaic panels in an industrial building

Abstract Environmental protection depends on energy production and use, which are responsible for ∼94% of carbon emissions. The lack of sufficient energy resources has led EU countries to alternatives for Green Energy production. Albania’s national response to climate change has been limited to some small changes mainly in the sector of the integrated water and environmental management legislation. However, in terms of changing the energy law, no effort has been made to prioritize green energy production. Doing so it is expected to contribute to the overall goal of reducing greenhouse gas emissions through the integration of clean energy solutions. The paper is referred to a specific case study focused on renewable energy using photovoltaic panels in an industrial building in Saranda, as the city with the most hours of sunshine per year in Albania. To support renewable energy initiatives, it is being emphasized with the help of statistical methods that Saranda has strong potential to invest in energy production through solar panels, which give rise to long-term renewable energy solutions. In summary, there are being identified three main factors that seemed to contribute to the results of national renewable energy solutions: 1) Creating renewable energy zones, 2) Installing solar panels for electricity generation 3) Enforcing regulations. In such conditions when energy of any kind is the most demanded product, green energy is the best way to manage it. It is being used in any country, but especially in Albania, which has a high average of sunny days, compared to other European countries, is an immediate requirement and, as such it should be stripped of it all useless bureaucracies to enable a higher production of it, even with state subsidies. But development will also have to overcome the above issue by adapting to energy production in small units where bureaucratic hurdles are even smaller.

State of the art on solid–gas sorption based long-term thermochemical energy storage

Solid-gas sorption thermochemical heat storage technology is an innovative and promising solution for storing heat over long periods. The review focuses on the construction of composite sorption thermochemical heat storage materials and binary mixed salt materials with porous matrix as the supporting materials, which can further improve the hydration rate and cycle stability of single hydrated salt. Furthermore, the heat storage capabilities of the metal halide/ammonia working pair make it suitable for extreme environments, surpassing the limitations of water-based working pairs in terms of low-temperature adaptability. It is worth noting that common solid–gas reactors and measures to enhance heat and mass transfer are also reviewed. Meanwhile, the efficient open and closed heat storage systems and their optimization schemes are introduced, and the feasibility of the practical operation of the heat storage systems is evaluated comprehensively from the technical and economic perspectives, and the future research challenges are prospected.

Sustainable integration of mineral resources, low carbon transition, and economic resilience in China

Mineral sustainability has become a crucial topic for economists in recent decades. This study provides key insights into China's sustainability challenges, particularly regarding ferrous mineral production, economic resilience, and low-carbon transition goals. Using data from 1980 to 2022 analyzed with the ARDL technique, the research highlights significant negative impacts of ferrous mineral production, economic uncertainty, and carbon emissions on green energy progress. This underscores the need for urgent actions to enhance sustainability in the mineral sector and support green energy initiatives. Economic instability hampers long-term green energy development, making economic resilience essential. Sustainable population management is also crucial due to its effects on green energy advancement. Conversely, ICT advancements offer promise for sustainable development. China should implement a comprehensive policy framework focused on sustainable mineral use, carbon reduction, and economic stability, including measures such as promoting electric vehicles and improving green tax efficiency.

Online Optimization in UAV-Enabled MEC System: Minimizing Long-Term Energy Consumption Under Adapting to Heterogeneous Demands

Online Optimization in UAV-Enabled MEC System: Minimizing Long-Term Energy Consumption Under Adapting to Heterogeneous Demands

Choosing the best locations to establish a nuclear power plant in Iraq with respect to radioactivity in those areas

Abstract Iraq is in a good position to run its nuclear power plant to prepare for long-term energy needs, including electricity demands. The ideal location for the nuclear power plant was identified in this study, as were the standards for choosing that location. Salah al-Din and portions of Anbar were the options. This research takes into account seven criteria: low population density, residential area, river access, topography, and land use. The criteria are represented in GIS layers, a GIS analysis is conducted to provide many proposed sites, and the criteria are categorized based on the weight distance value. To protect the lives of the station employees, the natural radioactivity of the research region was also monitored. The effectiveness of the site suitability map lies in its capacity to evaluate and display the suitability rates for nuclear power plants. The nearest quarter for distance of water sources of the total samples, which is No. (15, 11, 19, 20 and 13), the water sources are (Tigris River, Haditha Dam, Tigris River, Tigris River, and Tharthar Lake). As for the distance from the city centers, the furthest quarter of the samples were chosen from the residential areas, which are each of the samples with No. (14, 13, 10, 6 and 12) respectively. To the city centers (Tikrit City, Tikrit City, Tikrit City, Rawa City, and Kubaisa City) respectively, with distances (51256, 50385, 38308, 30934, and 25392).

7562 Longitudinal Untargeted Proteomics of Leptin Administration in Lean Humans Under Short- And Long-Term Energy Deficiency: Novel Physiological Insights and Pleiotropic Immunomodulatory Effects From Two Randomized, Placebo-Controlled Clinical Trials

7562 Longitudinal Untargeted Proteomics of Leptin Administration in Lean Humans Under Short- And Long-Term Energy Deficiency: Novel Physiological Insights and Pleiotropic Immunomodulatory Effects From Two Randomized, Placebo-Controlled Clinical Trials

Effects of multi-scale turbulent motions on aerodynamic performance of wind turbine under sand-laden conditions

Wind turbine installation in the desert and Gobi regions offers a promising approach for meeting long-term energy demands. However, the effect of multi-scale characteristics in sand-laden atmosphere flows on wind turbine aerodynamic performance has not been evaluated. In this study, wind velocity data collected from the Qingtu Lake Observation Array (QLOA) were employed to address this gap. Results show that up to 58% of the total turbulent kinetic energy (TKE) is accounted for by very large-scale motions (VLSMs), which make up a considerable portion of the TKE. The contributions of the large-scale motions (LSMs) and the small-scale motions (SSMs) to TKE are 36% and 6%, respectively. The contribution of multi-scale turbulent motions to the aerodynamic loads of wind turbine under sand-laden conditions has been quantified for the first time. The comparison demonstrates that while LSMs and SSMs exhibit a rapid drop in their contributions to wind turbine loads with height, VLSMs show a rapid increase. Wavelet analysis revealed a strong correlation between VLSMs and power, thrust, and blade root flapwise moment at periods ranging from 256 to 1024 s. This correlation weakens as the streamwise length scale of the turbulent coherent structure decreases. This study provides essential insights for optimizing wind turbine design and site selection in sand-laden environments.

Sequential decision-making under uncertainty for long-term energy transition planning

Sequential decision-making under uncertainty for long-term energy transition planning

Study on the Pathway of Energy Transition in Inner Mongolia under the "Dual Carbon" Goal

As an important strategic energy base in China, Inner Mongolia's energy exports are dominated by coal and electricity. Under the background of "double carbon" target, the energy transition of Inner Mongolia is of great significance to China’s energy security and carbon emission reduction. Based on the energy policy simulation model (EPS model), this paper explores the path of energy transition in Inner Mongolia by constructing the scenarios of developing renewable energy, developing CCS technology and carbon pricing, and simulating the policy situation based on the reality of Inner Mongolia and the energy transition experience of developed countries and regions. The results show that (1) The energy production and power generation under the development of renewable energy scenario (RE) and carbon pricing scenario (CP) are lower than the "Business as usual" scenario (BAU) for a certain period of time, which affects China's energy security. However, by 2060, power generation and energy production under both scenarios exceed the BAU scenario, and the energy production structure is dominated by renewable energy in both cases. (2) If the Inner Mongolia government focuses on short-term carbon emission reduction, the government should actively promote the establishment of a carbon emission trading market and increase the use of renewable energy through the improvement of the carbon pricing mechanism to promote carbon emission reduction in Inner Mongolia. If the Inner Mongolia government focuses on long-term energy supply stability, it should vigorously develop CCS technology.

Role of green finance and higher education in fostering the sustainability and energy transition practices

This paper offers a qualitative analysis of how higher education and green finance impact the promotion of sustainable energy within the Regional Comprehensive Economic Partnership (RCEP) region from 2000 to 2020. The analysis reveals that higher education has a positive effect on sustainable energy development, with a 1% increase in the higher education population associated with a 0.19% rise in short-term and a 0.29% rise in long-term sustainable energy progress. Green finance also plays a crucial role, significantly accelerating green energy development in the RCEP region—each 1% increase in green finance results in a 0.43% boost in short-term and a 0.38% boost in long-term sustainable energy advancement. In contrast, increased fossil fuel production hampers sustainable energy development. Enhanced internet access further supports green energy progress, contributing to a 0.43% increase in the short-term and a 0.53% increase in the long-term. Policy recommendations include expanding the green finance market, advancing sustainable education initiatives, reducing reliance on fossil fuels, and improving internet access to further sustainable energy development in the RCEP region.

Efficacy of machine learning algorithm in estimating oxyhydrogen gas generation system: Electrolyte concentration and current influence on sustainable energy production

Hydrogen gas has emerged as a promising and ecologically friendly substitute for fossil fuels, providing a long-term energy alternative. This research study applies machine learning regression models for estimating the volume of HHO gas generated using two distinct electrolytes with varying concentrations, namely sodium hydroxide (NaOH) and potassium hydroxide (KOH). The efficiency of the HHO gas production system hinges on various factors, such as the type of electrolyte and electrode, distance between electrodes, applied current and voltage. This investigation employed a comprehensive array of 29 multiple-regression algorithms to predict gas production. Notably, the input data for these algorithms were directly fed from the collected experimental data without any preprocessing. The input variables include the electrolyte concentration, current, and voltage, while the output is the estimated production of HHO gas. The findings of this study revealed that the multilayer perceptron (MLP) regression algorithm yielded the highest correlation coefficients, registering values of 0.9945 for NaOH and 0.9942 for KOH, respectively. Root relative squared error, relative absolute error, root mean squared error, mean fundamental error, and correlation coefficient were the metrics used to determine the model performance in predicting the volume of HHO gas produced. Furthermore, the experimental analysis demonstrated a direct relationship between the concentration of the electrolyte solution and the current with the rate of HHO gas production. Notably, the study identified that operating the cell at 40 A with KOH resulted in the maximum productivity of 0.9 litres per minute (LPM) of HHO gas, representing a 16 % increase compared to NaOH. These findings underscore the potential of machine learning regression models in optimizing hydrogen production and highlight the advantages of KOH as an electrolyte in this context.

Experimental Study on Heat Recovery in a CaO/Ca(OH)2-Based Mechanical Fluidized Bed Thermochemical Energy Storage Reactor

Long-term storage of seasonally available solar energy and its provision to balance heating energy demand can contribute significantly to the sustainable use of energy resources. Thermochemical energy storage is a suitable process for this purpose, offering the possibility of loss-free long-term energy storing and heat supply. In order to develop suitable technical solutions for the use of this technology, novel reactor concepts and scientific questions regarding material and technology development are being investigated. In this publication, the energy storage process of a long-term energy storage system based on a ploughshare reactor is experimentally investigated under various technically relevant operating conditions. One specific aspect of this technology is related to the release of water vapour during the charging process. Therefore, this work focusses, in particular, on the possibility of technically utilizing the latent heat of the released water vapour in the range of 45 °C to 80 °C, which covers the operating requirements of common heating systems in households. The experiments have shown that the dehydration process enables the separation of two heat fluxes: the chemically bound energy for long-term storage and the physically (sensible and latent) stored energy for short-term applications. However, the limitation of gas transport was also identified as the most important influencing parameter for optimising the performance of the process.

Controllable heat release of supercooled Erythritol-based phase change materials for long-term thermal energy storage

Transeasonal heat storage in organic phase change materials (PCMs) present a promising solution to the intermittent nature of renewable energy. However, PCMs are prone to spontaneous crystallization during storage, leading to the loss of stored latent heat in low-temperature environments. In this study, we incorporated tetrasodium ethylenediaminetetraacetic acid (EDTA-4Na) and superabsorbent polymer (SAP) to erythritol (ERY), referred to as EES-PCMs, to overcome these challenges and achieve more controllable and stable thermal energy storage. The incorporation of EDTA-4Na and SAP into ERY significantly improves the supercooling stability and phase change enthalpy. The optimal ratio (EES-PCMs-2) of phase change enthalpy reaches an impressive 286.62 J/g, with stable performance maintained for 120 days at room temperature. The EES-PCMs-2 exhibits exceptional thermal cycling stability, retaining its properties even after 100 cycles. A novel air-triggered crystallization method is demonstrated, enabling a temperature increase from room temperature to 48.21 °C in 320 s after being exposed to air for long-term storage. This innovative approach effectively overcomes the limitations of traditional triggering mechanisms, providing a straightforward and efficient method for thermal management. The high thermal storage capacity, stability, and controlled exothermic properties of EES-PCMs position them as promising candidates for applications in seasonal solar thermal energy storage.

Recent Advances in Carbon-Based Interfacial Photothermal Converters for Seawater Desalination: A Review

Along with the rapid development of society, freshwater shortages have become a global concern. Although existing desalination technologies have alleviated this pressure to some extent, their long-term environmental impact and energy consumption are still questionable. Therefore, it is necessary to find a new effective way for seawater desalination with cleaner energy. Solar-driven interfacial water evaporation technology has the advantages of environmental protection, energy saving, high evaporation efficiency, low cost, and strong sustainability, and is considered one of the most effective technologies to relieve water resource stress. This review summarized the recent advances in carbon-based interfacial photothermal converters focused on the preparation methods of 2D and 3D photothermal absorbers, the potential ways to enhance the efficiency of photothermal conversion. Finally, this paper proposed the challenges and future trends of interfacial photothermal converters.

Modeling energy storage in long-term capacity expansion energy planning: an analysis of the Italian system

This paper presents a framework to represent short-term operational phenomena associated with renewables capacity factors and final service demand distributions in a capacity-expansion and integrated energy system optimization model. The aim is to study the potential role of energy storage technologies coupled with renewable energy sources aiding the decarbonization of the overall energy system. The proposed methodology is implemented in an energy system optimization model named Tools for Energy Model Optimization and Analysis (TEMOA) and then tested in a case study focused on the Italian energy system. We examine a collection of scenarios that includes reference time scale scenarios, time scale sensitivity scenarios, and technology alternative scenarios. This paper's findings indicate that energy storage is crucial for fully decarbonizing the Italian power sector by 2050 in the absence of a low-carbon baseload. Additionally, it suggests that approximately 10 % of Italy's electricity generation in 2050 should be routed through short-term energy storage devices.

The production and characteristics of glycogen synthesized by various strains of the thermoacidophilic red microalgae Galdieria grown heterotrophically

AbstractRed microalgae from the Cyanidiophyceae, particularly Galdieria sulphuraria and Cyanidioschyzon merolae, are primitive photosynthetic thermoacidophiles that thrive in acidic hot springs and geysers. Unlike most Cyanidiophyceae, Galdieria strains are metabolically flexible as they can switch from photoautotrophic growth in the light to heterotrophic growth in complete darkness. Galdieria sulphuraria is especially noteworthy for its accumulation of various commercially valuable, functional compounds such as glycogen and phycocyanin. Glycogen, a branched fractal-like polysaccharide composed of several thousands of anhydroglucopyranose units, can be added to cosmetic products and sports drinks as a moisturizer or slow-digestible carbohydrate. While the production and structural characteristics of the glycogen of G. sulphuraria 108.79, isolated from Yellowstone National Park, have been previously described, our investigation aimed to explore glycogen production and properties across various Galdieria strains from different locations. Our findings reveal that all examined strains produce substantial amounts of highly branched glycogen when grown heterotrophically on glycerol in the dark. Notably, the structural characteristics of Galdieria glycogen distinguish it from both eukaryotic and prokaryotic glycogen, exhibiting a significantly higher degree of branching, substantially shorter side chains, and a considerable extent of indigestibility. These findings support the hypothesis that this highly branched, small glycogen is a long-term energy store, enabling survival during extended periods of complete darkness.