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The utilization of geological formations, distinguished by natural porosity and permeability and protected by low-permeability caprock, has emerged as an effective strategy for carbon dioxide (CO2) storage. This method significantly contributes to mitigating anthropogenic greenhouse gas emissions and addressing the challenges of climate change. Recent research has unveiled the potential of CO2 to enhance geothermal heat energy extraction in geothermal reservoirs by acting as a subsurface heat exchange fluid. This review paper explores the viability of CO2 in augmenting geothermal heat energy extraction, comparing it to conventional water-based geothermal systems. Special emphasis is placed on CO2 plume geothermal (CPG) systems, characterized by rapid deployment and long-term utilization of geothermal energy resources. With the overarching objective of establishing net-zero energy communities, the analysis of such systems offers a comprehensive understanding of their features, providing a fresh perspective on extracted energy within the context of energy supply in integrated, sustainable energy in built systems. Notably, these systems demonstrate efficacy in meeting the power requirements of an energy community, spanning both distinct heating and electricity needs. However, the key challenge lies in selecting suitable locations. This scientific review aims to comprehend the characteristics of CPG under specific temperature and pressure conditions while optimizing subsurface permeability. This insight is pivotal for identifying future locations for CPG operations with the intent of powering small energy communities. [ABSTRACT FROM AUTHOR]

Nowadays, global climate change is likely the most compelling problem mankind is facing. In this scenario, decarbonisation of the chemical industry is one of the global challenges that the scientific community needs to address in the immediate future. Catalysis and catalytic processes are called to play a decisive role in the transition to a more sustainable and low-carbon future. This critical review analyses the unique advantages of structured reactors (isothermicity, a wide range of residence times availability, complex geometries) with the multifunctional design of efficient catalysts to synthesise chemicals using CO2 and renewable H2 in a Power-to-X (PTX) strategy. Fine-chemistry synthetic methods and advanced in situ/operando techniques are essential to elucidate the changes of the catalysts during the studied reaction, thus gathering fundamental information about the active species and reaction mechanisms. Such information becomes crucial to refine the catalyst's formulation and boost the reaction's performance. On the other hand, reactors architecture allows flow pattern and temperature control, the management of strong thermal effects and the incorporation of specifically designed materials as catalytically active phases are expected to significantly contribute to the advance in the valorisation of CO2 in the form of high added-value products. From a general perspective, this paper aims to update the state of the art in Carbon Capture and Utilisation (CCU) and PTX concepts with emphasis on processes involving the transformation of CO2 into targeted fuels and platform chemicals, combining innovation from the point of view of both structured reactor design and multifunctional catalysts development. [ABSTRACT FROM AUTHOR]

This paper estimates the efficiency of the power generation sector in the USA by using Window Data Envelopment Analysis (W-DEA). We integrate radial and non-radial efficiency measurements in DEA using the hybrid measure while we extend the proposed model by considering good and undesirable outputs as separable and non separable. Then in the second stage, we perform parametric and non-parametric econometric techniques in order to model the relationship between the calculated environmental efficiencies and economic growth in attaining sustainability. Our empirical findings indicate a stable N-shape relationship between environmental efficiency and regional economic growth in the case of global and total pollutants but an inverted N-shape in the case of local pollutants. This implies that attention is required when considering local and global pollutants and the extracted environmental efficiency scores. A clear message to policy makers and government officials is that climate change which calls for economic, environmental and social concern should be analyzed according to its dispersion and regional dimension. [ABSTRACT FROM AUTHOR]

Estimation of emissions of greenhouse gases (GHG) is becoming an established part of assessing sustainability within environmental impact assessment (EIA). However, a comparative study of 25 environmental impact statements (EISs) to analyse the practice of accounting for emissions during the EIA process suggests that consideration of the effects of development on emissions of GHG is poorly understood. The extent to which assessment is actually carried out is also inconsistent and sporadically implemented. A key indicator appears to be the varying and sometimes contradictory use of technical terminology, particularly of the term ‘carbon’ and its similar phraseology. This paper provides a critical evaluation of the differing terminology that is applied to GHG assessments undertaken as part of EIA process and explores the effect that misuse of these terms could have on an impact EIS. [ABSTRACT FROM PUBLISHER]