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Abstract As the main way for the long-distance transportation of refined products, multi-products pipelines are of vital importance to the regional energy security. The supply reliability evaluation of multi-product pipeline systems can improve the effective response to unexpected disruptions and guarantee the reliable oil supply. Based on reliability theory and pipeline scheduling method, an integrated supply reliability evaluation methodology for multi-product pipeline systems is proposed in this paper and the pumps failure, of which influence is the most complex, is focused on. In the methodology, the discrete-time Markov process is adopted to describe the stochastic failure and the Monte Carlo method is used to simulate the system states transition. With the pipeline flowrate upper limits under various pumps failure scenarios optimized in advance, the maximum supply capacity to the downstream markets in each trial is calculated by the pipeline scheduling model. Three indicators are also developed to analyze the pipeline supply reliability from the holistic and individual perspectives. At last, the methodology application is performed on a real-world multi-product pipeline system in China and the supply reliability is analyzed in detail according to the simulation results. It is proved to provide a practical method for the emergency response decision-making and loss prevention.

This paper offers a complete and verified model of DC trolleybus grids and examines the effect of the common modelling assumptions made in literature by using simulations, as well as bus and substation measurements from the grid of Arnhem, the Netherlands. An equivalent model for the overhead line impedance is offered taking into account the single line impedance, the supply and return lines, and the parallel connections between them. A case study shows that the feeder cables from the substations to the sections can be ignored, but only for certain substation power and feeder-line length ranges. On the other hand, the often-neglected regenerative braking, bus auxiliaries load, bilateral connections, and the exact nominal substation voltage are found to be crucial for the correct modelling of a trolleybus grid. ; Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. ; DC systems, Energy conversion & Storage

The amine-based post combustion carbon capture process is one of the most advanced and preferred technologies to reduce CO 2 emissions from point sources like power plants. The emissions of amine from capture plants is one of the biggest challenges faced by this technology. These emissions typically occur by means of aerosol/mist formation. To develop effective countermeasures, it is crucial to understand the dynamic behavior of aerosols within the column, which is currently not well understood. This manuscript presents the results from a study aiming to understand the mechanism of aerosol growth and its behavior along the absorber column in terms of particles number concentration, particle size distribution, and amine emissions. For that, a series of experiments were performed in TNO's bench scale CO 2 capture plant using 30 wt% monoethnolamine (MEA) as solvent. For a SO 3 and CO 2 concentrations of 5.25 ppm and 12.5 vol.% in the flue gas, MEA emissions at the top exit of the column were recorded as 1051 mg/Nm 3 (with vapour emissions of 381 mg/Nm 3 ). In the absence of SO 3 in the flue gas, inlet particle concentration was 2.71 × 10 7 /cm 3 and resulting MEA emissions reduced by 63.5%–383 mg/Nm 3 . From the bottom of the column until the point of maximum temperature, the MEA content in the vapour phase was consistent with the volatility of the solvent. After this point it drastically increases to 1051 mg/Nm 3 . Both the number of particles and the total particle mass has lowered from the bottom to the top of the column. For the benchmark test, inlet and outlet total particle concentration were found to be 6.24 × 10 7 /cm 3 and 2.3 × 10 7 /cm 3 respectively, while total particle mass is 2.22 mg/m 3 at inlet and 1.32 mg/m 3 at outlet. Particles with a dimeter below 0.006 ?m contribute the most to total particle concentration both at the inlet (50%) and outlet (32%), while particles with diameter of 0.087 ?m contributes the most to the total particle mass at inlet (47%) and outlet (55%). The measured total mass of particles was in the order of magnitude of 1 mg/m 3 . This is much lower than the expected aerosol mass emissions, in the order of magnitude of 1 g/Nm 3 based on FTIR emissions. No particles larger than 0.147 ?m were recorded, which might explain the low total mass recorded. The cause for this is still under investigation, but it suggests that the sampling procedure may induce systematic errors to the measurements. Nonetheless, the observations from this study have given further insight into the aerosol dynamics in the absorber column and corresponding emissions. © 2019 Elsevier Ltd

Communication-based distributed secondary control is deemed necessary to restore the state of islanding AC microgrids to set points. As its limited global information, the microgrids become vulnerable to cyber-attacks, which by falsifying the communicating singles, like the angular frequency, can disturb the power dispatch in the microgrids or even induce blackout by pushing the microgrids beyond the safe operation area and triggering the protection. To make the microgrids more cyber secure, adaptive resilient control for the secondary frequency regulation is proposed. It assumes that each converter is communicating with its adjacent converters. With the proposed control, the weight of the communication channel being attacked is automatically reduced, and the more the communicating signals are falsified, the further the weight of that communication channel is weakened. The proposed approach does not rely on attack detection and thereby is easy to implement; Besides, it still works when challenged by a combination of multi-attack signals; Moreover, it applies to multiple communication lines getting attacked cases. Finally, the effectiveness and feasibility of the proposed resilient control scheme are validated by both simulations and experimental results. ; Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. ; DC systems, Energy conversion & Storage ; Hydraulic Structures and Flood Risk

Recently, the supercritical carbon dioxide (SCO 2 ) power cycle has become a hotspot in the field of energy-efficient utilization. The utilization of additives in the power cycle has been proven to be an effective way to improve the SCO 2 power cycle efficiency. As one of the core components of the system, the influence of CO 2 -based mixtures on turbine performance needs to be further explored. In this study, the preliminary design and three-dimensional numerical simulation of a 500 kW radial-inflow turbine (RIT) for small-scale SCO 2 power systems were carried out. Furthermore, the design and off-design performance of high Reynolds number and small size turbine under the change of the CO 2 -based binary mixture compositions and mixing ratios were studied. Increasing the amount of nitrogen, oxygen, or helium into CO 2 has a negative effect on the RIT performance, and the appropriate amount of xenon or krypton can improve the turbine efficiency. Moreover, mixtures with higher krypton additions adapt to higher heat source conditions. The loss of the turbine stage passage shows that a large amount of helium greatly reduces the working fluid density, and the high amount of xenon has a great influence on the dynamic viscosity, which all makes the RIT operation deviate from the steady state. Therefore, the CFD model simulation fails indicating that RIT designed based on pure CO 2 may not run smoothly and continuously. The losses in the stage with pure CO 2 and CO 2 –Kr mixture were investigated. The results indicate that the losses originated from the stator cannot be ignored and that the improvement of efficiency is mainly owed to the reduction in clearance losses. There is no doubt that the viewpoints proposed in this paper have significant reference value for the practical application of the SCO 2 power cycle using mixtures. ; Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the ...

The ever-increasing organic waste generation in Malaysia is a significant contributor to greenhouse gas (GHG) emissions. However, organic wastes can be utilized to produce biogas by anaerobic digestion, which is a promising option for both energy and material recovery from organic wastes with high moisture content. Therefore, this study was formulated to investigate the feasibility of anaerobic co-digestion of three types of organic wastes generated in significantly huge quantities in Malaysia, namely palm oil mill effluent (POME), food waste (FW), and sewage sludge (SWS). The biomethane potential (BMP) test was used to evaluate the biomethane potential from these organic wastes under mesophilic conditions to establish a stable and balanced microbial community, which may lack in mono-digestion, to improve biogas production. Comparative performance was made at different food to microorganism (F/M) ratios to investigate methane production in three groups of assays, namely A, B, and C. In groups A and B, the effect of F/M ratio variation on methane production was investigated, while in group C, the effect of varying the co-substrate mixture on methane yield was examined. The findings showed that the highest methane yields achieved for mono-digestion of POME and SWS in group A were 164.44 mL-CH4/g-CODadded and 65.34 mL-CH4/g-CODadded, respectively, at an F/M ratio of 0.8 and 197.90 mL-CH4/g-CODadded for FW in group B at an F/M ratio of 0.5. In addition, the highest methane yield achieved from the anaerobic co-digestion was at 151.47 mL-CH4/g-CODadded from the co-digestion of the POME and SWS (50:50) at an F/M ratio of 1.7 in group A. Both AD and AcoD were tested to fit into two kinetic models: the modified Gompertz and the transfer function models. The results showed that the modified Gompertz model had a better fit and was more adjusted to the experimental results for both AD and AcoD. The importance of this research lies in the economics of anaerobically co-digesting these abundance feedstocks and the variations in their characteristics which were found to increase their methane yield and process efficiency in anaerobic co-digestion.

Intelligent electrical power grids, widely referred to as smart grids (SGs), rely on digital technology resources, especially communication and measurement devices, becoming a cyber-physical energy system. Massive data flow between grid elements makes smart grids more vulnerable to cyber-attacks. Power system state estimation (SE) - an essential function of energy management systems - is one of these data integrity attacks' targets. Integrity validation routines can fail when insufficient redundancy levels are reached, and spurious data occur. These levels are associated with critical data, i.e., those whose unavailability makes the grid unobservable. Data redundancy is a metric that gives a precarious indication that SE can run. Alternatively, it is more appropriate to quantify this function strength concerning its results' reliability, which can be achieved by criticality analysis (CA). This paper proposes a novel approach to visualize the results of an extensive CA through representative graphs; they facilitate understanding the usefulness of CA. Critical sets of measurements are generalized, and several metrics are proposed to reveal measuring system vulnerabilities, assisting the design of protection schemes to resist cyber-attacks. Simulations attained on the IEEE-30bus system evince significant improvements in the interpretation/use of CA. ; Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. ; Intelligent Electrical Power Grids

The service performances of asphalt pavement, especially rutting, will be inevitably affected by climate change. However, existing studies have generally focused on the rutting depth and rutting life, and thus became insufficient for comprehensively evaluating the influence of climate change on rutting over the service life. A resilience assessment method for asphalt pavement rutting is developed to solve the above problem. First, the original resilience method is extended to fit the system whose performance level continues to decline. Then, the calculation formulas of rutting resilience are derived by combining the rutting prediction model and the level assessment model. Subsequently, the influence degrees of climate change in representative cities on rutting resilience are studied. The results suggest that neglecting climate change in rutting design of asphalt pavement will lead to insufficient resilience, especially in northern China. Furthermore, the predicted temperature under RCP8.5 should be employed for asphalt pavement design. ; Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. ; Pavement Engineering

Abstract Local initiatives that address environmental issues are determined by the shared territory, history and culture of community members, which can lead to common values and goals. This paper focuses on the role of community-based entrepreneurship in protecting and managing the natural environment that impacts directly life quality of local residents, as social and natural systems manifest and evolve in a dynamic interdependence. We apply a case study methodology to capture the richness of community-based entrepreneurship and evidence the diversity of these initiatives. By presenting and analyzing three case studies on different types of environmentally-driven initiatives – considering the natural environment as an object, context or resource of entrepreneurial activities, we identify the main elements of community entrepreneurship and the factors influencing its manifestations. These elements are integrated into a synthetic model, which maps the relationships between various components and success factors of environmentally-driven community initiatives. Our findings provide a better understanding of community-based entrepreneurship and of the hidden mechanisms of collective initiative and action.

The literature on green mobility and eco-driving in urban areas has burgeoned in recent years, with special attention to using infrastructure to vehicle (I2V) communications to obtain optimal speed trajectory which minimize the economic and environmental costs. This article shares the concept with these studies but turns the spotlight on cyclists. It examines the problem of finding optimal speed trajectory for a cyclist in signalised urban areas. Unlike the available studies on motorised vehicles which predominantly designed for pre-defined, fixed traffic lights timing, this article uses an algorithm based on stochastic dynamic programming to explicitly address uncertainty in traffic light timing. Moreover, through a comprehensive set of simulation experiments, the article examines the impact of the speed advice's starting point as well as the cyclist's willingness for changing his/her speed on enhancing the performance. The proposed approach targets various performance metrics such as minimising the total travel time, energy consumption, or the probability of stopping at a red light. Hence, the resulting speed advice can be tailored according to the personal preferences of each cyclist. In a simulation case study, the results of the proposed approach is also compared with an existing approach in the literature.