• Energy Research

AbstractAutomotive sector is crucial for the economic and social system. Conversely, it also plays an important role in the global emissions balance with strong consequences on the environment. Currently the Research world is engaged in the reduction of the emissions, especially in order to contrast the Climate Change and reduce toxicity on humans and the ecosystem. This study presents a comparative Life Cycle Assessment, Well-to-Wheel, between the most common technology used in the automotive sector, i.e. the traditional petrol Internal Combustion Engine and the full Battery Electric Vehicle. The different configurations have been analysed within 17 different impact categories in terms of climate change, human health, resourced depletion and ecosystems. The Well-to-Wheel approach allows to focus the attention on the use stage of the vehicle, considering the local effects due to the direct emissions in high density urban zones and it mitigates the dependence of usage hypotheses, different scenarios and intrinsic differences between the various models of cars in circulation.

Abstract This study analyses the sustainability of a bioenergy system fed by residual biomass with high moisture content (citrus peel), which is designed in cogeneration mode and integrated with the factory generating the residue. The impacts of electricity production are comprehensively assessed by conducting thermodynamic and environmental analyses with a life cycle approach. Two scenarios were analyzed considering the differences in the process layouts between juice factories. The first scenario with wet feedstock (Scenario W) includes the drying process in the bioenergy plant's boundaries. A second scenario uses dry feedstock (Scenario D), and the drying process is considered outside the boundaries. The thermodynamic performances are assessed by life cycle energy/exergy efficiencies, the cumulative exergy demand of non-renewable resources (CExDnr), and energy/exergy return on investment. Additionally, a new renewability indicator is introduced, hereby named Integrated Renewability (IR), to consider the origin (renewable or non-renewable) of the resources substituted by the side products. The Life Cycle Assessment shows that the scrubbing process, fed with bio-oil, could undermine the system’s sustainability. The overall exergy efficiency was determined to be 0.29 and 0.24 for Scenario D and Scenario W, respectively. Compared to the electricity from the national grid (Italy), the integrated bioenergy system leads to lower life cycle exergy efficiencies in both scenarios (0.24 and 0.20 for Scenario D and Scenario W, respectively, Vs. 0.34 for national grid), higher IR (3.1 and 1.5 Vs. −0.9), lower CExDnr (0.32 and 0.33 vs. 1.9 MWh/MWhe), and lower climate change impacts (−332 and 1.29 vs. 447 kgCO2/MWhe).

Joining is critical in shipbuilding impacting significantly on several aspects, i.e., properties, lightness, aesthetics, assembly/disassembly, maintenance employed workforce, emissions of fumes or gases. Consequently, it requires a significant study on impacts and risks. The aim of this work is to apply the Life Cycle Assessment to a friction stir welding process between aluminium and steel. The results confirmed that this welding is among the most sustainable (i.e., low energy, absence of filler, inert gases, and consumables). Moreover, was introduced a functional unit (i.e., length of weld divided by the thickness squared) that allows to compare different geometries and process parameters.

Abstract To contrast the naval emissions in terms of Sulphur and Nitroxides, recently, the institution of Emission Control Areas has increasingly prompted shipowners to choose new-generation engines capable of using Liquified Natural Gas as a marine fuel. This study presents a comparative Life Cycle Assessment, cradle-to-grave, between two different engines on a cruise ferry. One is a traditional Diesel machinery system and the other is a Liquified Natural Gas one. The two configurations have been analysed within 17 different impact categories in terms of climate change, human health, resourced depletion and ecosystems. The studied phases of the ship's life were the building, operation and dismantling. The results showed and quantified the environmental differences deriving from the use of Liquified Natural Gas in all the phases of the life of the ship. Generally, the LNG propulsion has shown to be more environmentally performing, but, particularly interesting are the results in terms of climate change, influenced by lower CO2 emissions but also by the phenomenon of methane slip that can increase the CO2-equivalent effect. The energy costs of transport and liquefaction of gas also have an impact to consider. Analyses of uncertainty on the data and of sensitivity on fuel consumptions and losing of steel during the shipbuilding were carried out.

Our cultural society has made remarkable advancements in creating digital models that depict the built environment, landscape, and reality. The advent of technologies such as terrestrial laser scanning and drone-based photogrammetry, coupled with sophisticated software capable of processing hundreds of photographs to generate point clouds, has elevated the significance of three-dimensional surveying in documentation and restoration. Point cloud processing and modeling software enable the creation of precise digital replicas of the investigated architecture, which can be scaled down and transformed into physically identical models. Through the export of STL files and the utilization of both subtractive and additive 3D printing technologies, tactile models resembling traditional manually crafted plastics can be obtained. An exemplary study focuses on the Gothic church of Santa Maria Alemanna in Messina, Italy, where laser scanner surveys and 3D prints using various technologies were applied to different parts of the building. The models were produced using a CNC milling machine and a 3D printer for fused deposition modeling. The sustainability of these production technologies was assessed through a Life Cycle Assessment, demonstrating the environmental advantages of additive manufacturing, including the use of materials with high recyclability and lower energy consumption. Additionally, the additive approach helps reduce processing waste.

The naval sector holds paramount importance for the global economy, yet it entails significant environmental impacts throughout the entire life cycle of ships. This review explores the application of life-cycle assessment (LCA) in the naval sector, a methodology for evaluating the environmental impacts associated with all the life stages of a product or service. LCA analysis in the naval context is essential for identifying and mitigating environmental impacts, thus promoting more sustainable development of the sector. This work provides a comprehensive overview of current LCA applications in the naval sector, highlighting major environmental impacts, in particular focusing on greenhouse-gas emissions and climate change. Additionally, this study integrates an analysis of greenhouse-gas emissions using a normalization approach, which has enabled the comparison of various types of fuels and ships, thereby enhancing our understanding of their environmental impacts. Moreover, the limits and challenges to applying LCA in the naval sector are discussed, offering insights for future research and developments in the field. This review aims to raise awareness among policymakers, designers, and operators in the naval sector about the importance of adopting LCA for more sustainable and responsible management of naval activities, thereby contributing to the protection of the marine and global environment.