Publications

During the past 10 years the Korea Atomic Energy Research Institute (KAERI) has performed a study to control hydrogen gas in the containment of the nuclear power plants. Before the Fukushima accident analytical activities for gas distribution analysis in experiments and plants were primarily conducted using a multidimensional code: the GASFLOW. After the Fukushima accident the COM3D code which can simulate a multi-dimensional hydrogen explosion was introduced in 2013 to complete the multidimensional hydrogen analysis system. The code validation efforts of the multidimensional codes of the GASFLOW and the COM3D have continued to increase confidence in the use of codes using several international experimental data. The OpenFOAM has been preliminarily evaluated for APR1400 containment based on experience from coded validation and the analysis of hydrogen distribution and explosion using the multidimensional codes the GASFLOW and the COM3D. Hydrogen safety in nuclear power has become a much more important issue after the Fukushima event in which hydrogen explosions occurred. The KAERI is preparing a large-scale test that can be used to validate the performance of domestic passive autocatalytic recombiners (PARs) and can provide data for the validation of the severe accident code being developed in Korea

Hydrogen and its energy carriers such as liquid hydrogen (LH2) methylcyclohexane (MCH) and ammonia (NH3) are essential components of low-carbon energy systems. To utilize hydrogen energy the complete environmental merits of its supply chain should be evaluated. To understand the expected environmental benefit under the uncertainty of hydrogen technology development we conducted life-cycle inventory analysis and calculated CO2 emissions and their uncertainties attributed to the entire supply chain of hydrogen and NH3 power generation (co-firing and mono-firing) in Japan. Hydrogen was assumed to be produced from overseas renewable energy sources with LH2/MCH as the carrier and NH3 from natural gas or renewable energy sources. The Japanese life-cycle inventory database was used to calculate emissions. Monte Carlo simulations were performed to evaluate emission uncertainty and mitigation factors using hydrogen energy. For LH2 CO2 emission uncertainty during hydrogen liquefaction can be reduced by using low-carbon fuel. For MCH CO2 emissions were not significantly affected by power consumption of overseas processes; however it can be reduced by implementing low-carbon fuel and waste-heat utilization during MCH dehydrogenation. Low-carbon NH3 production processes significantly affected power generation whereas carbon capture and storage during NH3 production showed the greatest reduction in CO2 emission. In conclusion reducing CO2 emissions during the production of hydrogen and NH3 is key to realize low-carbon hydrogen energy systems.

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.

An increased demand for energy in recent decades has caused an increase in the emissions of combustion products among which carbon-dioxide is the most harmful. As carbon-dioxide induces negative environmental effects like global warming and the greenhouse effect a decrease of the carbon-dioxide emission has emerged as one of the most urgent tasks in engineering. In this work the possibility for the application of the polymer-based dense mixed matrix membranes for flue gas treatment was tested. The task was to test a potential decrease in the permeability and selectivity of a mixed-matrix membrane in the presence of moisture and at elevated temperature. Membranes are based on two different poly(ethylene oxide)-based polymers filled with two different zeolite powders (ITR and IWS). An additive of detergent type was added to improve the contact properties between the zeolite and polymer matrix. The measurements were performed at three different temperatures (30 60 and 90 °C) under wet conditions with partial pressure of the water equal to the vapor pressure of the water at the given temperature. The permeability of carbon-dioxide hydrogen nitrogen and oxygen was measured and the selectivity of the carbon-dioxide versus other gases was determined. Obtained results have shown that an increase of temperature and partial pressure of the vapor slightly increase both the selectivity and permeability of the synthesized membranes. It was also shown that the addition of the zeolite powder increases the permeability of carbon-dioxide while maintaining the selectivity compared to hydrogen oxygen and nitrogen.

In the proton exchange membrane fuel cells the required hydrogen must be produced in some way. The power generators in the path of these fuel cells generally include a steam reactor that through other fuels provides the needed energy to produce hydrogen. This study investigates a steam reactor powered by propane fuel consisting of a shell and tube heat exchanger. The shell contains a catalyst that receives the mixture of propane and steam and the tubes embedded inside the reformer contain hot gases that provide a suitable substrate for the reaction. Velocity and temperature fields inside the reformer species concentration control and reaction rate are studied. The conversion of reactants and yield of products are investigated according to the reaction rate. The results show that the hydrogen production yield can vary from 77.5 % to 92.2 %. The reaction rate can be controlled by the velocity and temperatures of the hot gases. However for the T=900 K full propane consumption is achieved at the reformer outlet.

NiCu alloy catalysts with varying composition for electrolysis in alkaline water have been prepared by DC magnetron co-sputtering under Ar gas environment at substrate bias of  60 V. Nanocrystallinity lattice parameters and grain size of the NiCu alloys have been measured by grazing incidence X-ray diffraction (GIXRD). Elemental and microstructural analysis of the NiCu alloy have been done by field emission scanning electron microscopy (FESEM) as well as transmission electron microscopy (TEM). To analyze the NiCu alloys activity towards hydrogen evolution reaction (HER) cyclic voltammetry measurements have been done in a 6 M KOH at room temperature and further HER activities have been correlated with the varying Cu concentration in NiCu alloy catalysts.

To limit the global temperature change to no more than 2 ◦C by reducing global emissions the European Union (EU) set up a goal of a 20% improvement on energy efficiency a 20% cut of greenhouse gas emissions and a 20% share of energy from renewable sources by 2020 (10% share of renewable energy (RE) specifically in the transport sector). By 2030 the goal is a 27% improvement in energy efficiency a 40% cut of greenhouse gas emissions and a 27% share of RE. However the integration of RE in energy system faces multiple challenges. The geographical distribution of energy supply changes significantly the availability of the primary energy source (wind solar water) and is the determining factor rather than where the consumers are. This leads to an increasing demand to match supply and demand for power. Especially intermittent RE like wind and solar power face the issue of energy production unrelated to demand (issue of excess energy production beyond demand and/or grid capacity) and forecast errors leading to an increasing demand for grid services like balancing power. Megawatt electrolyzer units (beyond 3 MW) can provide a technical solution to convert large amounts of excess electricity into hydrogen for industrial applications substitute for natural gas or the decarbonization of the mobility sector. The demonstration of successful MW electrolyzer operation providing grid services under dynamic conditions as request by the grid can broaden the opportunities of new business models that demonstrate the profitability of an electrolyzer in these market conditions. The aim of this work is the demonstration of a technical solution utilizing Pressurized Alkaline Electrolyzer (PAE) technology for providing grid balancing services and harvesting Renewable Energy Sources (RES) under realistic circumstances. In order to identify any differences between local market and grid requirements the work focused on a demonstration site located in Austria deemed as a viable business case for the operation of a largescale electrolyzer. The site is adapted to specific local conditions commonly found throughout Europe. To achieve this this study uses a market-based solution that aims at providing value-adding services and cash inflows stemming from the grid balancing services it provides. Moreover the work assesses the viability of various business cases by analyzing (qualitatively and quantitatively) additional business models (in terms of business opportunities/energy source potential grid service provision and hydrogen demand) and analyzing the value and size of the markets developing recommendations for relevant stakeholder to decrease market barriers.

Electric trains (ET) and hydrogen trains (HT) are considered zero emission at the point of use. True emissions are dependent upon non-tailpipe sources primarily in energy production. We present UK carbon dioxide (CO₂) operating emission model outputs for conventionally fuelled trains (CFT) ETs and HTs between 2017 and 2050 under four National Grid electricity generation scenarios.



Comparing four service categories (urban regional intercity and high speed) to private conventionally fuelled vehicles (CFV) and electric vehicles considering average distance travelled per trip under different passenger capacity levels (125% 100% 75% 50% and 25%).



Results indicate by 2050 at 100% capacity CFTs produce a fifth of the emissions of CFVs per kilometre per person. Under two degree generation scenario by 2050 ETs produced 14 times and HTs produced five times less emissions than CFTs. Policymakers should encourage shifts away from private vehicles to public transport powered by low carbon electricity.

The Just Transition Commission started work in early 2019 with a remit to provide practical and affordable recommendations to Scottish Ministers. This report sets out their view of the key opportunities and challenges for Scotland and recommends practical steps to achieving a just transition<br/><br/>Climate action fairness and opportunity must go together. Taking action to tackle climate change must make Scotland a healthier more prosperous and more equal society whilst restoring its natural environment. We want a Scotland where wellbeing is at the heart of how we measure ourselves and our prosperity. We know that the scars from previous industrial transitions have remained raw for generations. We know that some more recent aspirations for green jobs have not delivered on all the benefits promised for Scottish workers and communities. We need rapid interventions to fully realise the potential (and mitigate the potential injustice) associated with the net-zero transition.

Aiming to elucidate physical property affecting to hydrogen gas permeability of polymer materials used for liner materials of storage tanks or hoses and sealants under high-pressure environment as model materials with different free volume fraction five types of polyethylene were evaluated using two methods. A convenient non-steady state measurement of thermal desorption analysis (TDA) and steady-state high-pressure hydrogen gas permeation test (HPHP) were used both under up to 90 MPa of practical pressure. The limit of TDA method of evaluation for the specimens suffering fracture during decompression process after hydrogen exposure was found. Permeability coefficient decreased with the decrease of diffusion coefficient under higher pressure condition. Specific volume and degree of crystallinity under hydrostatic environment were measured. The results showed that the shrinkage in free volume caused by hydrostatic effects of the applied hydrogen gas pressure decreases diffusion coefficient resulting in the decrease of permeability coefficient with the pressure rise.