Materials Design and Assessment of Redox-Mediated Flow Cell Systems for Enhanced Energy Storage and Conversion.

The pressing climate change issues have intensified the need for a rapid transition towards a bio-based circular carbon economy. Harnessing acetogenic bacteria as biocatalysts to convert C1 compounds such as CO2, CO, formate, or methanol into value-added multicarbon chemicals is a promising solution for both carbon capture and utilization, enabling sustainable and green chemical production. Recent advances in the metabolic engineering of acetogens have expanded the range of commodity chemicals and biofuels produced from C1 compounds. However, producing energy-demanding high-value chemicals on an industrial scale from C1 substrates remains challenging because of the inherent energetic limitations of acetogenic bacteria. Therefore, overcoming this hurdle is necessary to scale up the acetogenic C1 conversion process and realize a circular carbon economy. This review overviews the acetogenic bacteria and their potential as sustainable and green chemical production platforms. Recent efforts to address these challenges have focused on enhancing the ATP and redox availability of acetogens to improve their energetics and conversion performances. Furthermore, promising technologies that leverage low-cost, sustainable energy sources such as electricity and light are discussed to improve the sustainability of the overall process. Finally, we review emerging technologies that accelerate the development of high-performance acetogenic bacteria suitable for industrial-scale production and address the economic sustainability of acetogenic C1 conversion. Overall, harnessing acetogenic bacteria for C1 valorization offers a promising route toward sustainable and green chemical production, aligning with the circular economy concept.

Hybrid pumped hydro and battery storage for renewable energy based power supply system

Heterogeneous electrode materials possess abundant heterointerfaces with a localized "space charge effect", which enhances capacity output and accelerates mass/charge transfer dynamics in energy storage devices (ESDs). These promising features open new possibilities for demanding applications such as electric vehicles, grid energy storage, and portable electronics. However, the fundamental principles and working mechanisms that govern heterointerfaces are not yet fully understood, impeding the rational design of electrode materials. In this study, the heterointerface evolution during charging and discharging process as well as the intricate interaction between heterointerfaces and charge/mass transport phenomena, is systematically discussed. Guidelines along with feasible strategies for engineering structural heterointerfaces to address specific challenges encountered in various application scenarios, are also provided. This review offers innovative solutions for the development of heterogeneous electrode materials, enabling more efficient energy storage beyond conventional electrochemistry. Furthermore, it provides fresh insights into the advancement of clean energy conversion and storage technologies. This review contributes to the knowledge and understanding of heterointerfaces, paving the way for the design and optimization of next-generation energy storage materials for a sustainable future.

Over the last few decades several innovative ideas have been explored in the energy storage areas, ranging in size, capacity, design complexity, and targeted applications. Some of them are designed for large scale power system applications, others for smallor medium-scale renewable energy or hybrid power systems, while the others are designed to perform short-term energy storage ride through for critical infrastructure (communication systems, hospitals, military facilities, etc.). Energy storage has become an enabling technology for renewable energy applications, grid integration and enhancing power quality and stability in the power transmission and distribution, having a great potential to improve power grid quality and stability and to provide an alternative to fossil fuel-based energy generation. The major constraints for renewable energy penetration are the availability, intermittency, and variability, which can be addressed through energy storage. The energy storage choice depends on specific usage requirements, often incorporating several energy storage systems in order to increase system reliability, capacity, and supply security. In the electric power system, the renewable energy promise lies in its potential to increase grid efficiency, reliability, or in optimizing power flows and supporting variable power supplies. The parameters used in comparisons of various energy storage technologies include efficiency, energy capacity and density, run time, costs, system's response time, lifetime in years and cycles, self-discharge, and maturity of each energy storage technology. The most common energy storage technologies include compressed air, pumped hydro, batteries, fuel cells, flywheels, and super-capacitors. The last four are suitable for the medium scale applications. The chapter discussed energy storage technologies and gives an up to date comparative summary of their performances. After completing this chapter, the readers are able to understand the role, importance, configurations and topologies of energy storage systems, operation principles, characteristics, performances, and operation of major energy storage systems used in power systems, buildings, and industrial facilities. Another benefit is that readers are able to understand the critical role and necessity of energy storage systems in power and renewable energy systems, the differences between large-, mediumand small-scale energy storage systems, and how a system is selected on specific applications based on system characteristics and performances. Major energy storage technologies discussed in this chapter are compressed air energy storage, pumped hydropower storage systems, batteries, flywheels, hydrogen energy storage, fuel cells, supercapacitors, and superconducting energy storage systems. Thermal energy storage systems are covered in detail in the next chapter. This chapter provides comprehensive reviews of the energy storage technologies and gives an up to date comparative summary of their performances, characteristics, and applications.

Over the last few decades several innovative ideas have been explored in the energy storage areas, ranging in size, capacity, design complexity, and targeted applications. Some of them are designed for large scale power system applications, others for smallor medium-scale renewable energy or hybrid power systems, while the others are designed to perform short-term energy storage ride through for critical infrastructure (communication systems, hospitals, military facilities, etc.). Energy storage has become an enabling technology for renewable energy applications, grid integration and enhancing power quality and stability in the power transmission and distribution, having a great potential to improve power grid quality and stability and to provide an alternative to fossil fuel-based energy generation. The major constraints for renewable energy penetration are the availability, intermittency, and variability, which can be addressed through energy storage. The energy storage choice depends on specific usage requirements, often incorporating several energy storage systems in order to increase system reliability, capacity, and supply security. In the electric power system, the renewable energy promise lies in its potential to increase grid efficiency, reliability, or in optimizing power flows and supporting variable power supplies. The parameters used in comparisons of various energy storage technologies include efficiency, energy capacity and density, run time, costs, system's response time, lifetime in years and cycles, self-discharge, and maturity of each energy storage technology. The most common energy storage technologies include compressed air, pumped hydro, batteries, fuel cells, flywheels, and super-capacitors. The last four are suitable for the medium scale applications. The chapter discussed energy storage technologies and gives an up to date comparative summary of their performances. After completing this chapter, the readers are able to understand the role, importance, configurations and topologies of energy storage systems, operation principles, characteristics, performances, and operation of major energy storage systems used in power systems, buildings, and industrial facilities. Another benefit is that readers are able to understand the critical role and necessity of energy storage systems in power and renewable energy systems, the differences between large-, mediumand small-scale energy storage systems, and how a system is selected on specific applications based on system characteristics and performances. Major energy storage technologies discussed in this chapter are compressed air energy storage, pumped hydropower storage systems, batteries, flywheels, hydrogen energy storage, fuel cells, supercapacitors, and superconducting energy storage systems. Thermal energy storage systems are covered in detail in the next chapter. This chapter provides comprehensive reviews of the energy storage technologies and gives an up to date comparative summary of their performances, characteristics, and applications.

Peering into Batteries: Electrochemical Insight Through In Situ and Operando Methods over Multiple Length Scales

Toward a circular economy for plastics

Plastic waste pollution is a growing environmental and economic challenge in Africa, driven by rapid urbanization, increased plastic consumption, and inadequate waste management infrastructure. Traditional linear waste management models, characterized by “take, make, and dispose” practices, have led to significant environmental degradation and public health risks. A circular economy (CE) approach offers a sustainable alternative by promoting plastic waste reduction, reuse, and recycling, transforming waste into valuable resources. This review explores circular economy principles and their application in plastic waste management across African urban centers. Key opportunities include job creation, resource efficiency, private sector investment, and policy-driven waste management reforms. However, challenges such as weak regulatory frameworks, limited infrastructure, informal sector integration, and low public awareness hinder full adoption. The study emphasizes the need for multi-stakeholder collaboration, technological innovation, and policy alignment to achieve a sustainable circular plastic economy in Africa. Keywords: Circular economy, plastic waste, waste management, sustainability, Africa, recycling, policy, innovation

ABSTRACTIn recent years, the circular economy (CE) has emerged as a critical strategy for sustainable development, addressing environmental challenges, resource efficiency, and waste reduction. Although the advantages of CE over traditional linear economic models are well‐documented, less attention has been given to understanding how CE is perceived and discussed in public forums such as social media. This paper aims to fill that gap by analyzing Twitter conversations related to CE from 2012 to 2022, using advanced Natural Language Processing (NLP) techniques. A total of 389,575 tweets were collected and processed to uncover the main themes, trends, and influential entities in the global CE discourse. The analysis shows that waste management, recycling, and resource efficiency are the most prevalent topics, reflecting the public's concern for practical CE applications. Additionally, technological advancements such as blockchain and IoT are emerging as significant drivers of CE innovation. Countries like the United Kingdom, China, and India, along with key organizations like the European Commission and the Ellen MacArthur Foundation, are central to the global CE narrative. These findings provide critical insights for policymakers, corporations, and researchers, highlighting areas of public interest and potential collaboration to advance CE initiatives. By aligning strategies with social media discourse, stakeholders can promote more effective, widespread adoption of CE principles.

The fast development of electrochemical energy storage devices necessitates rational design of the high-performance electrode materials and systematic and deep understanding of the intrinsic energy storage processes. Herein, the preintercalation general strategy of alkali ions (A = Li+ , Na+ , K+ ) into titanium dioxide (A-TO, LTO, NTO, KTO) is proposed to improve the structural stability of anode materials for sodium and lithium storage. The different optimization effects of preintercalated alkali ions on electrochemical properties are studied systematically. Impressively, the three electrode materials manifest totally different capacities and capacity retention. The efficiency of the energy storage process is affected not only by the distinctive structure but also by the suitable interlayer spacing of Ti-O, as well as by the interaction effect between the host Ti-O layer and alien cations with proper size, demonstrating the pivotal role of the sodium ions. The greatly enhanced electrochemical performance confirms the importance of rational engineering and synthesis of advanced electrode materials with the preintercalation of proper alkali cations.

Novel Mo-doped nickel sulfide thin sheets decorated with Ni–Co layered double hydroxide sheets as an advanced electrode for aqueous asymmetric super-capacitor battery

Purpose This study aims to address the research gaps in the application of circular economy (CE) principles within the construction demolition industry (CDI) by providing an updated overview of key themes, trends and challenges. Using a bibliometric approach, it seeks to highlight the transformative potential of CE adoption in CDI, focusing on strategies for waste reduction, resource efficiency and supply chain optimization to support sustainable development. Design/methodology/approach Bibliometric analysis using the Scopus database was employed to systematically review the literature on CE principles in the CDI from 2014 to 2023. The analysis involved a four-step assessment, including qualitative reviews and quantitative evaluations, to identify key themes, trends, challenges and opportunities in CE research within the CDI. The intricate relationship between CE principles with a specific emphasis on CDI, building practices and supply chain management was explored. Findings The findings underscore a significant emphasis on circularity principles, interdisciplinary collaboration and the integration of emerging technologies for efficient waste management. Experiencing a remarkable annual growth rate of 60.58%, particularly evident over the past five years, the escalating volume of relevant publications reflects an expanding interest in the CE within the CDI and related supply chain subjects. This underscores academia’s pivotal role in advancing the transition toward a circular construction economy. Originality/value The study recommends refining CE strategies by exploring the circular design paradigms, optimizing supply chains, integrating digital technologies, establishing standardized metrics and scrutinizing CE’s impact within the CDI.

Circular Urban Metabolism Framework

Integrating circular economy (CE) principles into battery design is critical for enhancing sustainability in energy storage, as lithium‐ion batteries grow essential for renewable energy and electric mobility. However, raw material depletion, hazardous waste, and inefficient end‐of‐life (EoL) practices threaten long‐term resource and environmental sustainability. This study reviews 94 sources, synthesizing material flow analyses, design innovations, recycling technologies, and policy frameworks to assess CE applications across the battery lifecycle. Fourthemes emerge: 1) recovery of critical materials like lithium, cobalt, and nickel via emerging recycling methods that reduce energy consumption and environmental impact; 2) design innovations such as modularity and disassembly‐oriented approaches that enable reuse and efficient resource recovery; 3) second‐life battery use in stationary renewable energy systems to extend lifespan and lower costs; and 4) regulatory mechanisms, including extended producer responsibility and digital product passports to support circular practices. Key barriers include limited recycling infrastructure, complex chemistries hindering disassembly, lack of data transparency, and fragmented regulations reducing producer accountability. Promising solutions involve low‐impact recycling, standardized modular designs, blockchain‐based material traceability, and harmonized policies enforcing EoL responsibility. The study proposes a forward‐looking framework combining technological innovation and policy reform driven by interdisciplinary collaboration to transform batteries into regenerative assets aligned with CE goals.

Highlights The case study farm produces 66% of its biogas from off-farm food waste sources, highlighting the potential to increase the circularity of food and agricultural systems when farms capture and recycle external waste sources. The farm can meet 78% of its crop nitrogen needs from waste products recycled in digestion, assuming a 37% nitrogen use efficiency (NUE). However, phosphorus in the imported food waste creates an excess relative to crop needs. The farm creates an excess of energy that is returned to the electric grid, providing broader off-farm benefits through a circular economy approach. Widespread commercial implementation of circular economy principles in the U.S. dairy sector requires more measured data about how farms successfully implement circularity within the constraints of market incentives and farm operations. Abstract. Coupling agricultural production with sustainable bioenergy systems may help us improve the circular economy of the food system and work within planetary boundaries for climate stabilization. However, leading sustainable dairies often do not have data to support that claim. As a result, practical case studies of circular economies with measured data from commercially operating farms are lacking in the literature, which is instead dominated by hypothetical and theoretical analyses. To grow and scale commercial implementation of circular economy and sustainability principles, it is important to understand how commercial farms implement these principles within the constraints of market incentives and actual farm operations. We conducted a case study of a commercial dairy farm in Pennsylvania, where a well-managed anaerobic digester system serves as the basis for a circular farm economy and allows the next generation to grow the farm business and expand the portfolio of revenue streams. The farm recycles food and agricultural waste into heat, renewable electricity, and fertilizer to heat and power the farm, amend the soil, and reduce farm costs. We also highlight the potential to scale the case study farm's circular economy approach in Pennsylvania using the state's projected 2030 manure, corn stover, winter double crops, switchgrass, and food waste resources to produce energy via biogas or renewable natural gas (RNG). We estimate the state could generate 40 million MJ annually from such integrated anaerobic digestion systems, meeting 3% of its electricity consumption. Circular economies like this case study can be designed in food and agricultural systems to operate within the constraints of an operating farm and recycle waste, produce nitrogen- and phosphorus-rich soil amendments and reduce imports of synthetic fertilizers, reduce and offset fossil energy consumption and greenhouse gas emissions associated with crop and livestock production, regenerate natural ecosystems, help ensure agricultural resilience and sustainability, and provide economic benefits. Keywords: Anaerobic digestion, Biogas, Circular economy, Digestate, Food waste.