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Item type:Publication, Access status: with files , Unlocking sustainable solutions : harnessing residual biomass from Colombia's non-centrifugal sugar chain for green market deployment(Elsevier, 2024-06-01); ; 19 191 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Life cycle assessment of construction and driving operation of a hydrogen-powered truck built from a used diesel truckOne option to reduce greenhouse gas (GHG) emissions from heavy-duty vehicles is switching to hydrogen as a fuel, which is converted in drive trains powered by fuel cells. In addition to the production of new hydrogen trucks, it is also possible to convert used diesel-powered trucks to hydrogen-powered vehicles. This paper aims to evaluate the environmental impact of a heavy-duty truck converted from diesel propulsion to a hydrogen fuel cell drive regarding life-cycle GHG emissions and mineral resource scarcity (MRS). This life cycle assessment focuses on the construction and end-of-life phases of the vehicle (first part) and on the entire life cycle, including the use phase (second part). The largest share of GHG emissions for the hydrogen-powered truck (first part) originates from the tank system and the chassis, specifically due to the materials reinforced plastics, steel, and aluminum. The fuel cell system is responsible for half of the MRS, mainly due to the used platinum, which, as well as steel, accounts for about one-third of the MRS. The hydrogen supply path is the most crucial factor determining the overall GHG emissions (second part). To reduce GHG emissions compared to a conventional diesel-driven truck, the share of renewable energy within the power mix has to be at least 61 %. The MRS increases with an increasing share of renewable energy within the power mix. To reduce GHG emission of a converted hydrogen-powered truck, the use of reinforced plastics and platinum should be minimized, thus contributing to more efficient use of mineral resources.Publicationtype: Journal Article64 175 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Freshwater Demand and Availability for Green Hydrogen ProductionGreen hydrogen, produced from renewable energy sources (e.g., by electrolysis), is projected to play a pivotal role in the defossilization of a wide range of applications. Water is a fundamental component of this process, as hydrogen (H2) production via electrolysis requires water (H2O) as a raw material to be split into hydrogen and oxygen. However, freshwater is a scarce resource in many regions of the world, and densely populated areas are increasingly experiencing water scarcity. This trend is likely to be exacerbated by ongoing climate change and global population growth. From an economic perspective, sunny and dry regions of the planet seem particularly suitable for hydrogen production due to their abundant solar energy. However, water availability for hydrogen production depends on more than just physical supply; factors such as water quality, the regeneration of water reserves, and local social and environmental impacts of water withdrawal must also be considered. Therefore, this article examines the availability of water for green hydrogen production across various regions of the world.Publicationtype: Book part43 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , A general procedure to identify indicators for evaluation and monitoring of nature-based solution projectsIn the last years, the idea of using natural elements or nature-based solutions (NbS) to mitigate the impacts of cities on climate, biodiversity and citizens' health became more popular in research and practice. Nevertheless, there are currently uncertainties in finding and selecting appropriate criteria and indicators for monitoring and evaluating the impact and performance of NbS and its co-creation processes. This paper proposes an easy-to-use and structured procedure for selecting appropriate criteria and indicators for monitoring and evaluating any kind of NbS project. The user is guided step by step in selecting meaningful metrics. The procedure is tested using a real case study from the Horizon 2020 research project CLEVER Cities as an example. The test shows that by following the indicated procedure, the criteria and indicator selection process is speeded up and reproducible.Publicationtype: Journal ArticleScopus© Citations 7 82 195 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Assessment of critical resource use in aircraft manufacturing(Springer, 2022-03-01); ; ; ; The global aircraft fleet has been expanding worldwide, leading to a high demand for primary resources. Simultaneously, recycling initiatives for decommissioned aircraft are still incipient. Following circular economy principles, the aims of this paper are to identify potentially critical resources used and related environmental impacts, to derive recommendations regarding recycling, and to analyze the influence of increasing utilization of lightweight composite materials in aircraft manufacturing. It was identified that the engine is the structure containing resources with the highest scarcity, with tantalum dominating seven of the eleven analyzed impact categories. Aluminum, titanium, and nickel were shown to lead to the highest environmental impacts. Hotspots in the criticality and environmental assessment often occur due to alloying resources with a low mass share. It was shown that aluminum and steel alloy recycling should be prioritized. A higher lightweight composite material share in the aircraft increases impacts in the categories climate change and fossil resource depletion by 12% and 20%, respectively, whereas the impact of the category acidification, political stability, and demand growth decreases by 16%, 35%, and 60%, respectively.Publicationtype: Journal ArticleScopus© Citations 6 112 304 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Technical and environmental analysis on the power production from residual biomass using hydrogen as energy vector(2021-09); ; ; Decarbonization of energy by using renewable sources is a global need to tackle climate change. Herein, we report on the techno-environmental analysis of the use of sugarcane press-mud, a residual biomass, as feedstock to produce power in a fuel cell by using hydrogen (H2) as energy vector. Technical analysis was performed by using experimental and Aspen plus simulation results whereas environmental analysis was assessed through life cycle assessment. Raw bioethanol was used as H2 source, which was purified by three different technologies, i.e., flash, mash, and rectification columns. Mash column was selected as the suitable process to purify bioethanol for producing H2 and power, mainly ascribed to the reduction of bioethanol impurities that increases H2 yield, reduces energy demand, and mitigates the environmental impact in terms of global warming potential and acidification potential. This technology presented an energy efficiency of 56 %, a renewability factor of 1.24 and a carbon footprint of 1.21 kg CO2 kWh−1. Additionally, the use of residual biomass showed environmental benefits in comparison with the use of first-generation bioethanol from sugarcane molasses. Therefore, using sugarcane press-mud as power source in rural areas can diversify the energy sources to move towards a decarbonized economy.Publicationtype: Journal Article70 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Life cycle assessment of electricity generation from combustion and gasification of biomass in MexicoOne measure to mitigate some of the nowadays environmental problems is the generation of products from renewable resources. In this context, this study's objective is to evaluate the environmental impacts associated with the use of sugarcane and agave bagasse from Mexico as a raw material for the generation of bioenergy, applying a life cycle assessment approach. Four scenarios were compared to determine the optimal feedstock (sugarcane or agave) and processing routes (combustion or gasification) from an environmental perspective. Life cycle assessment is performed according to the cradle-to-gate approach. In the case of the two-feedstocks studied, it was observed that the feedstock processing stage has high impact values in almost all impact categories. In this sense, it was observed that the combustion scenarios have high impact values in terms of ozone depletion potential (4.73 × 10−6 and 7.59 × 10−7 kg CFC11 eq), terrestrial acidification potential (1.41 × 10−2 and 7.82 × 10−3 kg SO2 eq), and fossil fuel potential (9.30 × 10−2 and 0.12 kg oil eq) for sugar extraction and bacanora production, respectively). For the gasification scenarios, the highest impact values were observed for the terrestrial acidification potential (1.27 × 10−2 kg SO2 eq) and fossil fuel potential (8.41 × 10−2 kg oil eq) for sugar production and the ozone depletion potential (6.85 × 10−7 kg CFC11 eq), human toxicity potential - non-cancer (2.05 × 10−2 kg1,4-DCB) and fossil fuel potential (0.11kg oil eq) for bacanora production. Furthermore, it was observed that the sugarcane cultivation stage generates between 2 and 6 times more impact than the agave cultivation stage for almost all impact categories. Regarding the stages related to thermochemical processes, the impact values were relatively low, except for the following categories global warming potential, photochemical oxidation formation potential - humans, photochemical oxidation formation potential - ecosystems, terrestrial acidification potential, and water consumption potential, between 21 % and 88 % for the combustion process and between 32 % and 63 % for the gasification process. The main results of the comparisons between the four scenarios showed that the best scenario from an environmental perspective is agave bagasse combustion, followed by agave bagasse gasification, sugarcane bagasse gasification, and sugarcane bagasse combustion.Publicationtype: Journal Article58 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Life cycle inventory data for power production from sugarcane press-mudThis data article is associated with the research article “Technical and environmental analysis on the power production from residual biomass using hydrogen as energy vector”. This paper shows the procedure to calculate the Life Cycle Inventory (LCI) of the foreground system to perform the Life Cycle Assessment (LCA) of the power production from sugarcane press-mud. Said process encompasses four main stages: i) bioethanol production; ii) bioethanol purification; iii) syngas production and purification; and iv) power production. Additionally, other processes such as biomethane production and manufacturing of catalyst were included. Foreground data related to bioethanol production was gathered from experimental procedures at lab-scale. While foreground data, concerning the other processes such as bioethanol purification, syngas production and purification, power production, and biomethane production, was built by using material and energy flows obtained from Aspen Plus®. Lastly, LCI of the catalyst manufacturing was built based on literature review and the approach stated by Ecoinvent. All the inventories are meaningful to carry out future environmental assessments involving sustainable energy systems based on bioethanol, biomethane, or hydrogen.Publicationtype: Data PaperScopus© Citations 5 133 225 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Life cycle assessment of bioethanol production : a review of feedstock, technology and methodology(Multidisciplinary Digital Publishing Institute (MDPI), 2021-05-02); ; ; So far, a lot of efforts have been put in life cycle assessments (LCA) of bioethanol production. There are many works that have assessed bioethanol production in different points of view to illustrate the environmental impacts. This study reviewed former LCA studies on bioethanol produced from various biomass resources by considering the effect of methodological components, technical pathways and feedstock provision on the result of LCA studies. The review evaluated 48 papers published 2002–2021 with a focus on studies that included a complete set of environmental impact categories. However, due to lack of harmony among studies, comparing the LCA results was challenging but the review indicated that the final results of studies are influenced by LCA methodological components, such as system boundary, functional unit, etc. Around 80% of the reviewed papers show the reduction in global warming potential, while contrary results have been found about increasing acidification, eutrophication and photochemical oxidant formation impact categories because of the feedstock provision. Regarding technical aspects, results from the review revealed that most of the studies considered the pre-treatment as a crucial step in bioconversion processes. Despite several LCA studies of bioethanol production, there is still low attention given to uncertainty analysis in the publications.Publicationtype: Journal ArticleScopus© Citations 31 149 294 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Die HOOU an der TUHH : Erfahrungen und Erfolge 2020In 2020, 16 projects were sponsored and implemented within the Hamburg Open Online University at the University of Technology Hamburg. In this booklet, the lessons learnt within these projects are consolidated.Publicationtype: Text2052 408