development and performance analysis of biowaste based microbial fuel cells fabricated employing additive manufacturing technologies

Abstract In this work two different configurations of MFCs are tested, evaluating the importance of the operative conditions on power production. All the MFCs were fabricated employing 3D printing technologies and, by using biocompatible materials as for the body as for the electrodes, are analyzed the point of strength and development needed at the state of the art for this particular application. Power productions and stability in terms of energy production are deepen investigated for both the systems in order to quantify how much power can be extracted from the bacteria when a load is fixed for long time

structural health monitoring algorithm application to a powerboat model impacting on water surface

Abstract In naval field, live monitoring of local strains and displacements in the hull is the basis for dynamic studies such as checking the design limits, sea-keeping tests in smooth and rough seas, fatigue life estimation and damage detection. Vessels sailing on water are subject to impulsive loadings and local deformations; in these conditions the damage detection in real time becomes crucial. In this paper, a numerical methodology is proposed to measure the deformation of the whole structure of a powerboat entering the water free surface starting from local strain measurements, obtained numerically in a FE simulation. A modal decomposition approach has been used to reconstruct the structural response of the whole boat body. The reconstruction algorithm is calibrated for this study by means of the normalized modal strains matrix obtained through a FEA. A transient FE analysis is implemented to generate local strain signals from virtual sensors. In this analysis hydrodynamic loading resulting from well-known models are applied. The positioning and number of the virtual reference and control sensors are investigated. Virtual control sensors are utilized to compare strains with respect to the reconstructed quantities. Subsequently, the structural health monitoring algorithm has been applied to the powerboat model with a localized damage on the structure. The results reported in the paper reveal the capability of the method to detect the damage in real time

live reconstruction of global loads on a powerboat using local strain fbg measurements

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Preliminary design of a fuel cell/battery hybrid powertrain for a heavy-duty yard truck for port logistics

Abstract The maritime transport and the port-logistic industry are key drivers of economic growth, although, they represent major contributors to climate change. In particular, maritime port facilities are typically located near cities or residential areas, thus having a significant direct environmental impact, in terms of air and water quality, as well as noise. The majority of the pollutant emissions in ports comes from cargo ships, and from all the related ports activities carried out by road vehicles. Therefore, a progressive reduction of the use of fossil fuels as a primary energy source for these vehicles and the promotion of cleaner powertrain alternatives is in order. The present study deals with the design of a new propulsion system for a heavy-duty vehicle for port applications. Specifically, this work aims at laying the foundations for the development of a benchmark industrial cargo–handling hydrogen-fueled vehicle to be used in real port operations. To this purpose, an on-field measurement campaign has been conducted to analyze the duty cycle of a commercial Diesel-engine yard truck currently used for terminal ports operations. The vehicle dynamics has been numerically modeled and validated against the acquired data, and the energy and power requirements for a plug-in fuel cell/battery hybrid powertrain replacing the Diesel powertrain on the same vehicle have been evaluated. Finally, a preliminary design of the new powertrain and a rule-based energy management strategy have been proposed, and the electric energy and hydrogen consumptions required to achieve the target driving range for roll-on and roll-off operations have been estimated. The results are promising, showing that the hybrid electric vehicle is capable of achieving excellent energy performances, by means of an efficient use of the fuel cell. An overall amount of roughly 12 kg of hydrogen is estimated to be required to accomplish the most demanding port operation, and meet the target of 6 h of continuous operation. Also, the vehicle powertrain ensures an adequate all-electric range, which is between approximately 1 and 2 h depending on the specific port operation. Potentially, the hydrogen-fueled yard truck is expected to lead to several benefits, such as local zero emissions, powertrain noise elimination, reduction of the vehicle maintenance costs, improving of the energy management, and increasing of operational efficiency

performance of two different types of cathodes in microbial fuel cells for power generation from renewable sources

Abstract Microbial fuel cells (MFCs) technology represents a new approach to the sustainable electric power production, thanks to the advantages of its green features. The performance and the cost efficiency of a MFC are affected by several factors, such as the reactor architecture, the microbial microflora and the "costs per power" ratio of the electrodes. For example, cathodes powered by platinum as catalyzer are really efficient, but also expensive. In this study, two materials for cathode were examined: i) an economical biochar-based material (BC), ii) an activated carbon (AC) cathode with a nickel mesh current collector and a polytetrafluoroethylene (PTFE) binder to limit oxygen diffusion to the anodic compartment. The performances were evaluated in terms of power density and current density

Coupling of Biomass Gasification and SOFC – Gas Turbine Hybrid System for Small Scale Cogeneration Applications☆

Abstract In this study the performances of small cogeneration power plants fed by biomass and based on conventional and advanced technologies are presented. Three system configurations have been considered and analyzed. They are characterized by: a) a biomass gasification (G) unit, based on down-draft technology; b) a power unit, based on the SOFC technology or on the micro gas turbine (MGT) technology or on a hybrid configuration SOFC-MGT; c) a thermal recovery unit. The energy analysis of the proposed power plants has been conducted by using thermochemical/thermodynamic models able to study the integrated systems and each unit in terms of operating and performance parameters

Power to gas plant for the production of bio-methane: Technoeconomic optimization

In this work, a power to bio-methane plant in which the biogas is produced from an anaerobic digester plant and the hydrogen is generated by using an electrolysis unit powered by a renewable plant (photovoltaic or wind-based), is designed and sized. The plant sizing is carried out by applying a techno-economic multi-objective black box optimization approach. A numerical code, built by using the Matlab software package, is used to evaluate components sizes and to assess plant costs. This code is implemented in an optimization workflow developed in the modeFRONTIER environment. This approach allows to identify the optimal size of the plants components with the aim of maximizing the annual bio-methane producibility and minimizing its levelized cost. The results show that for a low-price electricity scenario (45 €/MWh) the minimum levelized cost of bio-methane (LCOBM), equal to 84.6 €/MWh, is obtained adopting the PV-based configuration. On the contrary, considering an high-price scenario (135 €/MWh), the minimum LCOBM is obtained for the Wind-based plant and is equal to 34.9 €/MWh

On the Emergy accounting for the evaluation of road transport systems: an Italian case study

Road transportation is one of the most polluting as well as energy-intensive sectors, and requires planning policies capable to address at the same time several different environmental, social, and economic issues. Cost-benefit analyses are generally carried out with a major focus on fuelling and driving efficiency, whereas a systemic approach appears to be needed for a more comprehensive evaluation of the alternatives that may become available to address any issue, be it intended for either short-term or long-term spans. For instance, building up a new infrastructure might allow for savings in time or fuel per km, but this may require an equivalent or even higher socio-environmental investment. In this work, a short review is presented of some systemic studies on transportation that use the emergy synthesis methodology. A case study is also addressed, concerning recent important expansion works on the Apennine Mountains section of the Italian major highway A1. In particular, the analysis points out the role of time saving, since for a new or renewed transport infrastructure (and when comparing for example road to rail transport) saved time is likely to become crucial in justifying civil enterprises. Nevertheless, the present emergy synthesis and the teaching of H.T. Odum (Odum & Odum, 2001) warn us that such “luxury” highly depends on the abundance of available energy, which is less and less given for granted, whereas a systemic analysis approach may indicate different levels of criticality when oriented towards environmental and well-being issues