Energy nexus最新文献

The interdependence between water and energy (water-energy nexus) has been identified as one of the major challenges at European level, with roadmaps calling for the development of integrated approaches in this sector. The increase in river temperature is at the heart of this nexus, with anthropogenic thermal pollution adding to the effect of global warming. River Water Heat Pumps can play a major role by decarbonising district heating network (DHN) while actively cooling the aquatic resource. Hence, the objective of this short communication is to identify the scientific challenges to be met and the progress to be achieved considering the current state of the art. To illustrate the point, a rapid evaluation of the potential is performed for the city of Lyon in France resulting in an achievable cooling of ∼1.5 K which is above the minimum threshold to see an effect on aquatic ecosystem while the CO₂ savings are significant for the DHN (∼ divided by a factor of 10). Because of its holistic nature, the impact assessment of such a system implies considering a wide diversity of indicators: energy, environmental, economics and sociological that need to be appropriately defined and quantified. In each field, progress beyond the state of the art to be performed has been identified, e.g. 4E analysis, cold water plume dispersion, integration of biodiversity in LCA.

The present work presents a literature review of solar-driven adsorption desalination systems (ADS) from the perspective of hybrid systems, adsorption materials, and system configurations. The evaluation criteria were based on the daily water production rate (SDWP), gain output ratio, coefficient of performance (COP), and the specific cooling power (SCP) of the dual-cooling and desalination systems. Recommendations for effective systems that require further research and development to increase water productivity and enhance system performance are also mentioned. First, concerning hybrid systems, adding an ejector to the adsorption desalination cycle showed a significant improvement in SDWP, reaching 40 m³/ton per day (TPD). In comparison, using two ejectors in the ADS integrated with HDH reached 83.1 m³/TPD at a cost estimated at 1.49 $/m³. Secondly, concerning system configurations, a wire wound finned tube heat exchanger of ADS achieved high performance. The SDWP, SCP, and COP were 23.5 m³/TPD, 682 W/kg, and 0.32, respectively. Thirdly, concerning adsorption materials, the results showed promising adsorbent materials in the range of solar energy temperatures, and on top of them was sodium polyacrylate (SP)/CaCl₂, where SDWP and COP were about 45 m³/TPD and 0.67, respectively, while the cost was estimated at 3.8 $/m³. Finally, it was recommended to introduce 2D adsorbents to improve the adsorption properties and heat exchangers with 3D structures to improve the overall heat transfer coefficient of ADS.

The relationships within the Energy-Water nexus are inherently complex, necessitating sophisticated methods to optimize and manage these interactions effectively. Metamodeling emerges as a crucial technique in abstracting these complex relationships into a manageable analytical form. This study adopts a systematic approach to construct Life Cycle Assessment (LCA) metamodels, aimed at examining the interactions within the water-energy nexus of various desalination technologies. A critical aspect of the developed methodology is the selection of sampling points that align with LCA scenarios through a tailored designed experiment (DoE) model. These scenarios, which include Reverse Osmosis (RO), Electrodialysis (ED), and Multi-Effect Distillation (MED), are evaluated using a set of indicators the Energy-Water nexus, across tradeoff nexus policies. The results signify the impact of considering the Energy-Water Nexus on optimizing desalination processes, compared to evaluating energy and water metrics independently. In policies where nexus considerations were not integrated—focusing solely on cumulative energy or exclusively on water footprint—the RO with Wind Turbine (RO[WT]) scenario emerged as the optimal solution. This configuration consumed 7.540 MJ and 1.654 m³ of water and a carbon footprint of 0.719 kg CO₂eq per cubic meter of desalinated water. Conversely, policies that incorporate a nexus approach favor the adoption of MED with Thermal Solar (MED[TS]) scenario. Characterized by its moderate energy consumption of 2.226 MJ, and a water footprint of 2.226 m³, per cubic meter. These findings illustrate the critical role of employing Energy-Water Nexus frameworks through metamodeling in minimizing the environmental impacts associated with desalination processes.

Biodiesel is generally obtained by transesterification and esterification of appropriate feedstocks facilitated by a catalyst. It has emerged to be one of the most potential alternatives for the conventional fuels gaining worldwide attention. Heterogeneous catalysts are usually preferred than homogeneous for biodiesel synthesis due to facile separation and insignificant soap formation. However, the separation still possesses difficulty leading to mass transfer hindrance. Therefore, these catalysts can be further modified using magnetic separation techniques to develop magnetically separable catalysts. The magnetic nanoparticles (MNPs) are notable appealing catalysts due to huge surface area, high activity, amicable functional groups and structures, adaptable properties, conformity in pore size, and facile separation have made them desirable catalyst carriers for biodiesel synthesis. The MNPs are modified via functionalization to construct magnetically recoverable heterogeneous nanocatalysts. Magnetic catalysts can be utilized as a befitting option for biodiesel synthesis as these are environmentally benign, highly reusable and economically viable. The current review article discusses different magnetic solid catalysts such as magnetic base, acid, biocatalysts and bifunctional of acid base catalysts for efficient biodiesel synthesis. The prime focus of this paper rest on the catalytic performances of various magnetically recoverable catalysts, mechanisms and recyclability for biodiesel production processes. The synthesis methods of magnetic heterogeneous base and acid nanocatalysts, magnetic properties, functionalization and their reciprocity on the catalytic activity are reviewed in this article.

In the face of urgent global environmental challenges, the pursuit of sustainable technologies has become of utmost importance. Thermoacoustic technology has emerged as a promising energy conversion method with potential applications in various domains such as power generation, waste heat recovery, refrigeration, and air conditioning. This technology harnesses the thermodynamic properties of sound waves to convert heat into work or create cooling effects, offering simplicity, reliability, and environmental friendliness. Thermoacoustic devices, including refrigerators and engines, offer a low-carbon alternative to conventional power and refrigeration systems. With minimal mechanical components and no moving parts, they boast durability, easy maintenance, and reduced susceptibility to breakdowns. Despite the advantages, thermoacoustic technology currently faces challenges such as lower efficiency compared to traditional technologies. To achieve efficient performance, these devices depend on a comprehensive understanding of complex flow physics, which encompasses the transient nature of phenomena and the conversion of thermal and acoustic energies. This work provides a comprehensive overview of recent advancements in thermoacoustic technology, specifically emphasizing prime movers and refrigerators. We present insights into the working mechanisms and performance-affecting parameters of these devices, while discussing future research prospects and obstacles to commercial implementation. This review highlights the need for a deeper understanding of thermoacoustic system mechanisms, with a focus on addressing efficiency and scalability challenges. To make thermoacoustic systems more practical, research endeavors should concentrate on unraveling nonlinear phenomena, developing nonlinear thermoacoustics, and advancing transduction systems, system design, and component optimization. Innovative design strategies, beyond traditional multi-stage and phase-change approaches, along with exploration of alternative energy sources, hold the key to significantly improving overall thermoacoustic system performance, ensuring the continual evolution and prosperity of the field in the decades ahead.

Conventional agriculture and the need to satisfy the demand for food, cause different types of pesticides to be used indiscriminately, causing them to be dispersed into ecosystems by wind and water currents, representing a serious environmental problem. For this reason, it is important to apply effective technologies for the elimination of pesticides from water bodies. In the present research, heterogeneous photocatalysis using ZnO as a photocatalyst was applied to evaluate the degradation of methamidophos in contaminated water prepared in ultrapure water and river water. Considering the working parameters of 3 g/L of zinc oxide, a concentration of 50 mg/L of methamidophos, with constant agitation of 300 rpm, temperature 25 ± 2 °C and a natural pH, methamidophos degradation percentages of 86.66 % and 57.96 % were achieved in ultrapure water and river water, respectively. The chloride, sulfates, nitrates, and nitrites anions present in the river water could be responsible for the decrease in the effectiveness of the photocatalytic process. The mathematical models that best describe the degradation process were the pseudo-second order model and the Elovich model.

The fishery-photovoltaic complementary industry is an emerging industrial model in China that integrates aquaculture with the solar industry. This innovative model involves conducting aquaculture activities while installing photovoltaic modules on the water surface to harness solar energy for electricity generation. However, despite its rapid growth in China, this model lacks substantial scientific data support across various domains. Therefore, based on an analysis of relevant research literature, this study reviews the current development status, environmental and economic effects, as well as challenges faced by the fishery-photovoltaic complementary industry in China. The aim is to provide scientific references for promoting sustainable development within this sector. The findings reveal that existing fishery-photovoltaic complementary industry projects are primarily concentrated in the middle and lower reaches of the Yangtze River and Pearl River Basin. The geographical distribution of these projects is predominantly influenced by local aquaculture areas and available solar energy resources, with a greater impact observed from the former rather than the latter. During summer months when water is shaded by photovoltaic panels, a slight decrease in the average water quality parameters across cases was observed, such as a decrease of 0.2 units in pH, a decrease of 1.06 °C in water temperature, a decrease in dissolved oxygen levels of 0.8 mg/L, inorganic nitrogen content and total phosphorus concentration dropped by 0.08 mg/L and 0.02 mg/L respectively. Conversely, there is a moderate increase noted in total nitrogen and ammonia nitrogen levels. The conclusion of the effect on phytoplankton biomass is not uniform, but it will certainly reduce zooplankton biomass. The impact on the species diversity of the zooplankton community was minimal, and its direction, whether positive or negative, varied depending on the specific aquatic ecosystem. A certain degree of shade is advantageous for the cultivation of shade-loving fish. Through the strategic deployment of photovoltaic panels and the implementation of scientific stocking practices, it is possible to achieve sustained levels of fisheries production. This model also can reduce an average of 978.6 tons of CO₂ emissions per megawatt per year through energy production, thus achieving the combined goals of energy conservation and emissions reduction, and ensuring the profitability of power generation. Additionally, compared with the land utilization area of 3.66 hm² per megawatt of traditional ground-mounted photovoltaics, fishery-photovoltaic complementary only requires 1.64 hm², which can significantly save land resources by utilizing water surfaces, which mitigates the conflict between land use for agriculture and renewable energy installations. At the same time, research also pointed out that the existence of fishery-photovoltaic complementary will inevitabl