H2 Safety in Human Operations – and Safety guideline

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Novel Heat Integration in a Methane Reformer and High Temperature PEM Fuel Cell-based mCHP System

AbstractA highly integrated and optimized heat recovery system is essential for efficient operation of a HTPEM fuel cell-based mCHP system. The main challenge with such system is to design energy efficient systems with low start-up time. Recent studies have shown that this can be achieved by proper heat integration of the balance of plant (BOP) components. This study proposed a novel scheme that optimally integrated the sub-components of a mCHP system consisting of a 2 kWel HTPEM fuel cell integrated with methane processing units, for recovery and use of the process and waste heat. A steady state system modeling and simulation of the complete mCHP system was implemented in Aspen Plus v7.2. The design of the heat recovery system was achieved with pinch analysis techniques. Heat integration results show that external cooling utility is not required and result in a 5% increase in the overall system efficienc

High-pressure PEM water electrolyser performance up to 180 bar differential pressure

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Simulating offshore hydrogen production via PEM electrolysis using real power production data from a 2.3 MW floating offshore wind turbine

This work presents simulation results from a system where offshore wind power is used to produce hydrogen via electrolysis. Real-world data from a 2.3 MW floating offshore wind turbine and electricity price data from Nord Pool were used as input to a novel electrolyzer model. Data from five 31-day periods were combined with six system designs, and hydrogen production, system efficiency, and production cost were estimated. A comparison of the overall system performance shows that the hydrogen production and cost can vary by up to a factor of three between the cases. This illustrates the uncertainty related to the hydrogen production and profitability of these systems. The highest hydrogen production achieved in a 31-day period was 17 242 kg using a 1.852 MW electrolyzer (i.e., utilization factor of approximately 68%), the lowest hydrogen production cost was 4.53 $/kg H2, and the system efficiency was in the range 56.1–56.9% in all cases.publishedVersio

Multi-Sine EIS for Early Detection of PEMFC Failure Modes

Electrochemical impedance spectroscopy (EIS) is a powerful technique that can be used to detect small changes in electrochemical systems and subsequently identify the source of the change. While promising, analysis is often non-intuitive and time-consuming, where collection times of a single EIS spectrum can reach several minutes. To circumvent the long collection times associated with traditional EIS measurements, a multi-sine EIS technique was proposed in which the simultaneous application of many frequencies can reduce the acquisition time to less than a minute. This shortened acquisition time opens the possibility to use multi-sine EIS as a real-time diagnostic tool for monitoring the state-of-health of commercial fuel cell systems. In this work, a single-cell proton exchange membrane fuel cell (PEMFC) was characterised using multi-sine EIS, by establishing steady-state impedance response under baseline conditions before systematically changing operating conditions and monitoring the dynamic changes of the impedance response. Our initial results demonstrate that full multi-sine EIS spectra, encompassing a frequency range from 50 kHz to 0.5 Hz, can be collected and analysed using simple equivalent circuit models in 50 s. It is shown that this timeframe is sufficiently short to capture the dynamic response of the fuel cell in response to changing operating conditions, thereby validating the use of multi-sine EIS as a diagnostic technique for in-situ monitoring and fault detection during fuel cell operation.publishedVersio

Modelling of fast fueling of pressurized hydrogen tanks for maritime applications

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Hydrogen energy systems : development and application of modelling tools

This paper deals with the modelling and optimisat ion of a series of typical hydrogen systems. The systems models have been developed on the TRNSYS 1 platform. The mathematical models and the methodology used for analysis are de scribed in this paper, as well as the validation of the models. An application on an island in Norway is also presented

Decarbonisation of transport: options and challenges

This EASAC report reviews options for reducing greenhouse gas (GHG) emissions from European transport. It argues for stronger policies to bridge the gap between the GHG emission reductions that will be delivered by current policies and the levels needed to limit global warming to less than 2°C or even 1.5°C (Paris Agreement). The report focusses on road transport because, in the EU, this contributes 72% of transport GHG emissions. EASAC recommends a combination of transitional measures for the next 10-15 years and sustainable measures for the long term, based on a three level policy framework: avoid and contain demand for transport services; shift passengers and freight to transport modes with lower emissions (trains, buses and ships); and improve performance through vehicle design, more efficient powertrains and replacing fossil fuels with sustainable energy carriers including low-carbon electricity, hydrogen and synthetic fuels. Opportunities for the EU to strengthen its industrial competitiveness and create high quality jobs are also discussed

Renewable energy and hydrogen system concepts for remote communities in the West Nordic region - The Nólsoy case study

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The case for high-pressure PEM water electrolysis

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