Effect of addition level of Pandanus amaryllifolius Roxb. on Broiler performances at starter period

Pandanus amaryllifolius Roxb. leaves are commonly used as food additives in many countries. Beside to improve taste, it is recognized to contain various compound groups namely alkaloid, saponins, flavonoids and tannins that have a role in antibacterial activity. However, the current research aim was to examine effect of using Pandanus amaryllifolius Roxb. leaves as feed additive in broilers. The method used was experiment, employing 6 treatments included P0: control feed; P0: control feed added with 0.1% zinc bacitracin; P1: control feed added with 0.5% Pandanus amaryllifolius Roxb. leaves powder; P2: control feed added with 1.0% Pandanus amaryllifolius Roxb. leaves powder; P3: control feed added with 1.5% Pandanus amaryllifolius Roxb. leaves powder; P4: control feed added with 2.0% Pandanus amaryllifolius Roxb. leaves powder. The variables measured were feed consumption, body weight gain and feed conversion ratio. The results indicated that in all variables no significant results were reported. Those indicated that addition of Pandanus amaryllifolius Roxb. leaves powder in broiler feed did not affect growth performances of broiler. It is concluded that the use of Pandanus amaryllifolius Roxb. leaves powder as feed additive did not change growth of broiler, probably due partly to its antibacterial effect.

Development of a plug-in fuel cell electric scooter with thermally integrated storage system based on hydrogen in metal hydrides and battery pack

The thermal management of lithium-ion batteries in hybrid electric vehicles is a key issue, since operating temperatures can greatly affect their performance and life. A hybrid energy storage system, composed by the integration of a battery pack with a metal hydride-based hydrogen storage system, might be a promising solution, since it allows to efficiently exploit the endothermic desorption process of hydrogen in metal hydrides to perform the thermal management of the battery pack. In this work, starting from a battery electric scooter, a new fuel cell/battery hybrid powertrain is designed, based on the simulation results of a vehicle dynamic model that evaluates power and energy requirements on a standard driving cycle. Thus, the design of an original hybrid energy storage system for a plug-in fuel cell electric scooter is proposed, and its prototype development is presented. To this aim, the battery pack thermal power profile is retrieved from vehicle simulation, and the integrated metal hydride tank is sized in such a way to ensure a suitable thermal management. The conceived storage solution replaces the conventional battery pack of the vehicle. This leads to a significant enhancement of the on-board gravimetric and volumetric energy densities, with clear advantages on the achievable driving range. The working principle of the novel storage system and its integration within the powertrain of the vehicle are also discussed.

Nanostructured gas diffusion layer to improve direct oxygen reduction reaction in Air-Cathode Single-Chamber Microbial Fuel Cells

The aim of this work is the development of new nanostructured-gas-diffusion-layer (GDL) to improve the overall behaviour of Air-Cathode Single-Chamber-Microbial-Fuel-Cells (SCMFCs). The design of new nanostructured-GDL allowed exploiting all nanofibers ’intrinsic properties, such as high surface ratio to volume, high porosity, achieving thus a good oxygen diffusion into the proximity of catalyst layer, favouring thus the direct oxygen-reduction-reaction (ORR). Nanostructured-GDLs were prepared by electrospinning process, using a layer-by-layer deposition to collect 2 nanofibers’ mats. The first layer was made of cellulose nanofibers able to promote oxygen diffusion into SCMFC. The second layer, placed outwards, was based on polyvinyl-fluoride (PVDF) nanofibers to prevent the electrolyte leakage. This nanostructured-GDL plays a pivotal role to improve the overall performance of Air-Cathode-SCMFCs. A maximum current density of 20 mA m-2 was obtained, which is higher than the one reached with commercial-GDL, used as reference material. All results were analysed in terms of energy recovery parameter, defined as ratio of generated power integral and the internal volume of devices, evaluating the overall SCMFC performance. SCMFCs with a nanostructured-GDL showed an energy recovery equal to 60.83 mJ m-3, which was one order of magnitude higher than the one obtained with commercial-GDL, close to 3.92 mJ m-3.

An algorithm for comparative analysis of power and storage systems for maritime applications

This paper presents an innovative algorithm to compare traditional and innovative energy systems onboard for maritime applications. The solutions are compared adopting a multi-criteria method, considering four parameters (weight, volume, cost, emissions) and their relevance according to the kind of ship and navigation route. The algorithm, which includes a large and updated database of market solutions, leads to the implementation of HELM (Helper for Energy Layouts in Maritime applications) tool. HELM was conceived to support the design of maritime systems: it chooses the best technology comparing traditional marine diesel engines, propulsion systems with alternative fuels (methanol, ammonia, LNG) and innovative low-emission technologies (fuel cell and batteries). Two case studies are investigated: (i) a small passenger ship for short routes (ii) and a large size ro-ro cargo ship. For case (i), fuel cells represent a competitive solution, in particular considering navigation in emission control areas. For case study (ii) Internal Combustion Engines shows are the best solution. The evaluation of alternative fuels is performed, considering a sensitivity analysis on emissions’ importance: methanol, LNG, and ammonia are promising solutions. For case (i), the installation of electrical batteries is also evaluated to analyse potential advantages to reduce the amount of H2 stored onboard.

Social Life Cycle Assessment of a Proton Exchange Membrane Fuel Cell stack

Hydrogen systems are gaining importance in view of a progressive decarbonisation of societies, and becoming more and more cost-competitive alternatives in many sectors (e.g., mobility). However, the sustainability of these technologies must be carefully assessed following a holistic approach which embraces not only environmental but also social aspects. Social Life Cycle Assessment (S-LCA) is an insightful methodology to evaluate potential social impacts of products along their life cycle. In the frame of the project eGHOST, social risks of a proton exchange membrane fuel cell (PEMFC) stack were assessed through an S-LCA. The functional unit was defined as one 48 kW stack (balance of plant excluded), targeted for mobility applications. The supply chain was defined assuming Spain as the manufacturing country and involving from the material/energy production plants to the stack manufacturing. Beyond conventional life cycle inventory data, trade information and additional inventory data were retrieved from the UN Comtrade and PSILCA databases, respectively. Besides, working hours for the manufacturing plants of the stack and its subcomponents were calculated based on literature data. Social life cycle inventories were modelled and evaluated using openLCA and the PSILCA method. Two stakeholder categories, workers and society, were considered through the following social indicators: child labour, contribution to economic development, fair salary, forced labour, gender wage gap, and health expenditure. The choice of these indicators is in line with the eGHOST project purpose. Despite the relatively small amount contained in the product, platinum clearly arose as the main social hotspot under each of the selected indicators. At the level of component plants, the manufacturing of bipolar and end plates was also found to be relevant under some indicators. On the other hand, electricity consumption generally accounted for a minor contribution. Overall, in order to avoid burden shifting from environmental to social issues, a careful design of technologies is needed.

Optimized design and simulation of a hybrid storage system based on hydrogen as an energy carrier

The integration of renewable energy sources into the electricity system can contribute to the development of a low-carbon economy. However, due to the intermittency and non-programmability of these sources, problems related to the management of local electricity grids may occur. A possible solution or limitation to these issues is given by the electrical storage. In addition, in the next future, domestic micro-grids are expected to play a fundamental role in electric power networks, driving both the academic and industrial research interests in developing highly efficient and reliable conversion and storage technologies. In this study, the behavior of a small-scale hybrid energy system for hydrogen production and storage has been predicted, by means of a developed calculation model, and the operational strategy of the system has been optimized with the aim to maximize the hydrogen production. In addition, with the aim to maximize the overall solar-to-hydrogen chain efficiency, the whole system model has been applied to different operating scenarios, to identify the optimal management strategy to control it.

Experimental characterization of a PEM fuel cell for marine power generation

This study is focused on the possible application of hydrogen-fed PEM fuel cells on board ships. For this purpose, a test plant including a 100 kW generator suitable for marine application and a power converter including a supercapacitor-based energy storage system has been designed, built and experimentally characterised. The plant design integrates standard industrial components suitable for marine applications that include the technologies with the highest degree of maturity currently available on the market. Fuel Cell generator and power converter have been specifically designed by manufacturers to fit the specific plant needs. The experimental characterisation of the plant has been focused on the evaluation of the efficiency of the single components and of the overall system. Results shows a PEM fuel cell efficiency of 48% (when all auxiliaries are included) and an overall plant efficiency, including power conditioning, of about 45%. From load variation response tests, the fuel cell response time was maximum 2 seconds without supercapacitors and increased up to 20 seconds with supercapacitors connected, reducing the stress on the fuel cell generator. Experimental results confirm that PEM fuel cells, when supported by a suitably sized energy storage system, represent a viable technical solution for zero-emission power generation on board ships.

On-site solar powered refueling stations for green hydrogen production and distribution: performances and costs

Today, the hydrogen is considered an essential element in speeding up the energy transition and generate important environmental benefits. Not all hydrogen is the same, though. The “green hydrogen”, which is produced using renewable energy and electrolysis to split water, is really and completely sustainable for stationary and mobile applications. This paper is focused on the techno-economic analysis of an on-site hydrogen refueling station (HRS) in which the green hydrogen production is assured by a PV plant that supplies electricity to an alkaline electrolyzer. The hydrogen is stored in low pressure tanks (200 bar) and then is compressed at 900 bar for refueling FCHVs by using the innovative technology of the ionic compressor. From technical point of view, the components of the HRS have been sized for assuring a maximum capacity of 450 kg/day. In particular, the PV plant (installed in the south of Italy) has a size of 8MWp and supplies an alkaline electrolyzer of 2.1 MW. A Li-ion battery system (size 3.5 MWh) is used to store the electricity surplus and the grid-connection of the PV plant allows to export the electricity excess that cannot be stored in the battery system. The economic analysis has been performed by estimating the levelized cost of hydrogen (LCOH) that is an important economic indicator based on the evaluation of investment, operational & maintenance and replacement costs. Results highlighted that the proposed on-site configuration in which the green hydrogen production is assured, is characterized by a LCOH of 10.71 €/kg.

Impedance-based Solid Oxide Fuel Cell testing as scalable and reliable Quality Control tool for cell and batch manufacturing: first findings

Testing is a necessary step in the manufacturing process of Solid Oxide Fuel Cells (SOFC) to assess the performance of the produced cells before on-field deployment. In this work, the implementation of Electrochemical Impedance Spectroscopy (EIS) and subsequent data elaboration via Equivalent Circuit Modelling (ECM) is evaluated as a viable experimental framework for characterization and Quality Control (QC) of cells or cell batches, complemented to standard polarization-based methods. By performing a statistical analysis of the ECM parameters (representative of each physico-chemical process) the cell and batch operational parameters can be determined and compared. The validity of the proposed methodology is assessed using a wide experimental dataset of a significant number of SOFC samples (20 cells from 3 batches – two of which identical and the third with an intentional modification in the manufacturing process in order to validate the proposed methodology) tested in identical conditions. Results show that the impedance-based method provide detailed information in terms of impedance breakdown (anode gas diffusion process resulting the main criticality), as well as confirming the preliminary results obtained from the polarization approach (Batch#2 showing the lowest total performance and highest uniformity). Highly reproducible intra-batch distributions of the ECM parameters encourage the applicability of such methodology for QC purposes, even with few data collected only in Open Circuit Voltage (OCV) conditions. A relevant deviation of charge transfer and diffusion resistances in Batch#3 respect to other batches is observed (not visible from the polarization curves), which is reconducted to the modified anode functional layer, opening potential applications of the proposed methodology to assess the impact of targeted modifications of manufacturing methods on specific cell electrochemical performances.

Digital Twin of Fuel Cell Hybrid Electric Vehicle: a detailed modelling approach of the hydrogen powertrain and the auxiliary systems

The transport sector is today a major source of pollutant and greenhouse gas emissions. Fuel Cell Hybrid Electric Vehicles are a solution to reduce its environmental impact, thanks to the zero pollutant tailpipe emissions and longer driving ranges if compared with full electric vehicles. A Digital Twin of a FCHEV is developed in this study, through the assessment of models of mechanical and thermal systems within the vehicle. The Simulink/Simscape model here presented is able to support both the design choices and the test of control strategies. The results obtained allow characterizing the impact of the auxiliary systems on the driving range, whose relative value ranges from 28% to 40% of the overall energy demand depending on the ambient temperature, and the range is between 430 km and 356 km respectively for mild and cold temperature.