Institution of Gas Engineers & Managers

This paper presents a simulation tool for marine hybrid power-plants equipped with polymer exchange membrane fuel cells and batteries. The virtual model through the combination of operational data and dynamically modelled subsystems can simulate power-plants of different sizes and configurations in order to analyze the response of different energy management strategies. The model aims to replicate the realistic behavior of the components included in the vessel's grid to asses if the hardware selected by the user is capable of delivering the power set-point requested by the energy management system. The model can then be used to optimize key factors such as hydrogen consumption. The case study presented in the paper demonstrates how the model can be used for the evaluation of a retrofitting operation replacing a diesel electric power-plant with fuel cells and batteries. The vessel taken into consideration is a domestic ferry operating car and passenger transport in Denmark. The vessel is outfitted with a diesel electric plant and an alternative hybrid power-plant is proposed. The hybrid configuration is tested using the model in a discrete time-domain.

Palladium (Pd) membranes are a promising enabling technology for power generation and hydrogen production with CO2 capture. SINTEF has developed and patented a flexible technology to produce Pd-alloy membranes that significantly improves flux and thereby reduces material costs. Reinertsen AS and SINTEF aim to demonstrate the Pd membrane technology for H2 separation on a side stream of the Statoil Methanol Plant at Tjeldbergodden Norway. In the present article we present the upscaling of the membrane manufacturing process together with the membrane module and skid design and construction.

The cost of storing and transporting hydrogen have been one of the main challenges for the realization of the hydrogen economy. Liquid organic hydrogen carriers (LOHC) are a promising novel solution to tackle these challenges. In this paper we compare the LOHC concept to compressed gas truck delivery and on-site production of hydrogen via water electrolysis. As a case study we consider transportation of by-product hydrogen from chlor-alkali and chlorate plants to a single industrial customer which was considered to have the greatest potential for the LOHC technology to enter the markets. The results show that the LOHC delivery chain could significantly improve the economics of long distance road transport. For economic feasibility the most critical parameters identified are the heat supply method for releasing hydrogen at the end-user site and the investment costs for LOHC reactors.

Presently the fulfilment of world’s energy demand highly relies on the fossil fuel i.e. coal oil and natural gas. Fossil fuels pose threat to environment and biological systems on the earth. Usage of these fuels leads to an increase in the CO2 content in the atmosphere that causes global warming and undesirable climatic changes. Additionally these are limited sources of energy those will eventually dwindle. There is huge urge of identifying and utilizing the renewable energy resources to replace these fossil fuels in the near future as it is expected to have no impact on environment and thus would enable one to provide energy security. Hydrogen is one of the most desirable fuel capable of replacing vanishing hydrocarbons. In this review we present the status of energy demands recent advances in renewable energy and the prospects of hydrogen as a future fuel are highlighted. It gives a broad overview of different energy systems and mainly focuses on different technologies and their reliability for the production of hydrogen in present and future.

ISSUES MONITOR 2020: DECODING NEW SIGNALS OF CHANGE

The annual World Energy Issues Monitor provides unique insight into what energy policymakers CEOs and leading experts identify as Critical Uncertainties and Action Priorities. New this year the Issues Monitor also provides readers with the views of the individual customer detailing their perceptions of their role in the overall energy system. The Issues Monitor report includes a global issues map 58 country maps and six regional maps as well as perspectives from Future Energy Leaders (FEL) and energy innovators.

GLOBAL PERSPECTIVES

The 2020 global map incorporates all survey responses representing the views of over 3000 energy leaders from 104 countries. In this era of transition defined by decentralisation digitalisation and decarbonisation energy leaders must pay attention to many different signals of change and distinguish key issues from the noise. The Issues Monitor identifies shifting patterns of connected issues shaping energy transitions.

A NEW PULSE

The focus for the 2010s was about trying to automate and upgrade the energy system and set targets to move the energy transition forward. Digitalisation accelerated the transition of all sectors towards a more customer-centric environment. New policies and regulations were introduced to facilitate this transition and empower consumers. As a result the 2020s may very well be about realising those targets through a transition from activism to action.

TREND TRACKING: CCS

In comparing response from the Oil & Gas sector in 2015 with 2019 we found that almost half of respondents identified Carbon Capture & Storage (CCS) as a high impact issue in 2019 up from about a third in 2015. CCS is increasingly being viewed as an essential option for continued hydrocarbon use although governmental support is needed to enable scalability and cost effectiveness.

A DIFFERENCE IN OPINION: NUCLEAR

Opinions remain polarised but in many European countries nuclear power is increasingly recognised as a carbon-free energy source and potentially an integral part of the future energy mix. In December 2019 the European Commission set a target of net-zero carbon emissions by 2050. There is qualified support among energy leaders to include nuclear energy to help create a carbon neutral continent and enable a just energy transition.

In this paper a novel process is developed to cogenerate 4741 kg/h of methanol 297.7 kW of electricity and 35.73 ton/h of hot water including a hydrogen purification system an absorption– compression refrigeration cycle (ACRC) a regenerative Organic Rankine Cycle (ORC) and parabolic solar troughs. The heat produced in the methanol reactor is recovered in the ORC and ACRC. Parabolic solar troughs provide thermal power to the methanol distillation tower. Thermal efficiencies of the integrated structure and the liquid methanol production cycle are 78.14% and 60.91% respectively. The process’s total exergy efficiency and irreversibility are 89.45% and 16.89 MW. The solar thermal collectors take the largest share of exergy destruction (34%) followed by heat exchangers (30%) and mixers (19%). Based on the sensitivity analysis D17 (mixture of H2 and low-pressure fuel gas before separation) was the most influential stream affecting the performance of the process. With the temperature decline of stream D17 from −139 to −149 °C the methanol production rate and the total thermal efficiency rose to 4741.2 kg/h and 61.02% respectively. Moreover the growth in the hydrogen content from 55% to 80% molar of the feed gas the flow rate of liquid methanol and the total exergy efficiency declined to 4487 kg/h and 86.05%.

With the growth of aviation traffic and the demand for emission reduction alternative fuels like the so-called electrofuels could comprise a sustainable solution. Electrofuels are understood as those that use renewable energy for fuel synthesis and that are carbon-neutral with respect to greenhouse gas emission. In this study five potential electrofuels are discussed with respect to the potential application as aviation fuels being n-octane methanol methane hydrogen and ammonia and compared to conventional Jet A-1 fuel. Three important aspects are illuminated. Firstly the synthesis process of the electrofuel is described with its technological paths its energy efficiency and the maturity or research need of the production. Secondly the physico-chemical properties are compared with respect to specific energy energy density as well as those properties relevant to the combustion of the fuels i.e. autoignition delay time adiabatic flame temperature laminar flame speed and extinction strain rate. Results show that the physical and combustion properties significantly differ from jet fuel except for n-octane. The results describe how the different electrofuels perform with respect to important aspects such as fuel and air mass flow rates. In addition the results help determine mixture properties of the exhaust gas for each electrofuel. Thirdly a turbine configuration is investigated at a constant operating point to further analyze the drop-in potential of electrofuels in aircraft engines. It is found that electrofuels can generally substitute conventional kerosene-based fuels but have some downsides in the form of higher structural loads and potentially lower efficiencies. Finally a preliminary comparative evaluation matrix is developed. It contains specifically those fields for the different proposed electrofuels where special challenges and problematic points are seen that need more research for potential application. Synthetically-produced n-octane is seen as a potential candidate for a future electrofuel where even a drop-in capability is given. For the other fuels more issues need further research to allow the application as electrofuels in aviation. Specifically interesting could be the combination of hydrogen with ammonia in the far future; however the research is just at the beginning stage.

The presence of a conductive layers of hot-formed oxide on the surface of bars for pre or post-compressing structures can promote localized attacks as a function of pH. The aggressive local environment in the occluded cells inside localized attacks has as consequence the possibility of initiation of stress corrosion cracking. In this paper the stress corrosion cracking behavior of high strength steels proposed for tendons was studied by means of Constant Load (CL) tests and Slow Strain Rate (SSR) tests. Critical ranges of pH for cracking were verified. The promoting role of localized attack was confirmed. Further electrochemical tests were performed on bars in as received surface conditions in order to evaluate pitting initiation. The adverse effect of mill scale was recognized.

This paper describes a 1-D numerical model for the prediction of heat and mass transfer through an intumescent paint that is applied to an on-board high-pressure GH2 storage tank. The intumescent paint is treated as a composite system consisting of three general components decomposing in accordance with independent finite reaction rates. A moving mesh that is employed for a better prediction of the expansion process of the intumescent paint is based on the local changes of heat and mass. The numerical model is validated against experiments by Cagliostro et al. (1975). The overall model results are used to estimate effect of intumescent paint on fire resistance of carbon-fibre reinforced GH2 storage.

Fast response and high durability hydrogen sensor is required in the safety management of hydrogen station and fuel cell vehicle. We had developed the catalytic combustion type hydrogen sensor in the shape of the miniature beads. It is using the optimized Pd-Pt/Al2O3 catalyst and the Pt micro-heater coil. Both warm-up time and response time of this sensor achieved less than 1 second by downsizing the element to 200μm diameter. Furthermore we improved the resistance of sensor poisoning to silicone vapor and confirmed long term stability within +/-10% of output error up to 8 years. Therefore we assume that our sensor technology contribute to hydrogen safety.