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Dynamic pressure measurements are introduced as a powerful tool to detected filter failures at early stage. Filter failures such as leakages and blockages can be detected during back pressure recleaning pulses. High frequency sensors enable the recording of the recleaning pressure pulse. Patchy cleaning and depth filtration can be detected much faster with dynamic pressure measurements than with differential pressure measurements. Parameters derived from dynamic pressure data can be observed over time and compared with reference data. The method complements conventional pressure difference measurements and is applied at a hot gas filter that implements coupled pressure pulse (CPP) technology. Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 837-843

With an increasing share of regenerative wind and solar energy in electricity supply, the aspect of load flexibility will gain importance, i.e. there is an increasing need for buffer capacities and / or power plants must be able to react more flexibly to changes of the demand. As an alternative or in addition to the new construction of peak­load power plants (pump storage systems, gas power plants), load-flexible dust burner technologies can be used in existing incinerators to increase the load flexibility and the fuel flexibility when using especially local regenerative fuel sources. Flexibility of the burner concept means an increase in changing fuel composition and non-stationary operation, which may cause changes of the combustion behavior and, hence, of the emission behavior. Flexibility in fuel sources changes the combustion and emission behavior, too, especially with regard to low rank fuels with high ash contents containing chlorine and alkali species. To control these non-stationary processes in the burner and downstream boiler area for an efficient operation, contact-free optical measurement methods are applied in addition to the measurement systems existing in the furnace chamber and furthermore control methods based on computational intelligence. Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 1334-1337

Wireless Sensor Networks (WSN) are a key component of the Internet of Things (IoT) revolution. WSN nodes are in general battery-powered, thereby and efficient usage of their energy budget is of paramount importance to avoid performance degradation in IoT applications. To this end, this chapter proposes techniques to manage the WSN nodes’ power consumption. The aim of the first technique is to minimize the transmitted power for a given quality of service requirement at the receiver side. To this end, a power control is considered at each WSN node as well as the use of multiple distributed access points at the receiver side. The second technique to reduce the WSN energy consumption is energy harvesting (EH). Namely, the use of artificial light EH is considered to extend the WSN lifetime. Thus, an experimental setup based on a photovoltaic cell, a boost converter and a commercial WSN node is presented. It is shown that under certain settings it is possible to extend the WSN node’s lifetime without bound, when the transmission time period is above a certain threshold.

Agentenbasierte Strommarktmodelle werden vielfach eingesetzt, um die Entwicklung des Strommarkts und Energiesystems explorativ zu untersuchen. Häufig werden hierbei auf Basis von Eingangszeitreihen die Investitions- und Dispatch-Entscheidungen von konventionellen Kraftwerken, wie Gas- oder Kohlekraftwerke, und Speichertechnologien nachgebildet . Modelle wie PowerACE und AMIRIS nutzen Brennstoffpreisreihe, Last, Erneuerbaren-Energien (EE)-Erzeugung und Investitionsoptionen sowie den bestehenden Kraftwerkspark als Eingangsdaten. Die zu Grunde gelegte Last und EE-Erzeugung sind hierbei stark vom jeweiligen Wetterjahr, auf denen sie basieren, abhängig. Zum einen ist das Wind- und Strahlungsdargebot als auch der Wärme- und Kältebedarf, welche einen starken Einfluss auf den Strombedarf haben, jedes Jahr unterschiedlich, gleichzeitig führen technologische Entwicklungen dazu, dass eine reine Skalierung historischer Erzeugung zukünftige EE-Erzeugung systematisch unterschätzt. Es soll untersucht werden, ob die Verwendung von nur einem Wetterjahr dazu führt, dass, insbesondere bei Betrachtungszeiträumen von mehreren Jahrzehnten, es beim Vergleich zwischen verschiedenen Wetterjahren zu erheblichen Unterschieden in den Simulationsergebnissen , sowohl bei den Investitionen als auch bei den Marktpreisen, kommt. Ziel ist es die Unsicherheiten in Bezug auf EE-Erzeugung und Stromnachfrage im Agentenverhalten abzubilden. In Rahmen dieser Arbeit soll diese Unsicherheit in den Ergebnissen agentenbasierter Modelle, am Beispiel PowerACE, quantifiziert werden und dargelegt werden, ob die Verwendung von mehreren Wetterjahren oder die Nutzung synthetische Wetterjahren, also eine Kombination verschiedener Wetterjahre auf Erzeugungs- und Nachfrageseite, hier einen Vorteil bieten .

Increasing the rate of renovation for the existing building stock is a crucial challenge for EU’s energy policy. The Smart City Block (SCB) project proposes an innovative answer to this challenge. The underlying hypothesis is that introducing a collective dimension to renovation could result in increasing rates of renovation while also impacting positively the efficiency of the renovation and the social ties within urban areas. The collective dimension considered is the city block in Brussels.The first part of this paper describes the theoretical part of the project that was necessary to develop an adapted methodology. It describes the SCB offering, Brussels segmentation and some results of surveys.The SCB offering shows that many different options can be proposed to the city block dwellers, ranging from a collective insulation, efficient heating systems and shared photovoltaics to collective kitchen garden in the inner space of the block, shared vehicles or shared spaces. This is especially relevant for Brussels where city blocks often have an inner space that could be used. Besides, the segmentation of Brussels based on city block characteristics offers a typology that can be further used to target specific environmental or social deficit.However, the collective dimension introduced in the project is challenging for western individualistic minds. In order to evaluate the acceptance of households, a survey was conducted on 4 city blocks in Brussels, representing over 450 households. It shows a clear willingness to investigate the concept further but only if concrete proposals with estimations of energy and financial savings are provided. Sharing space, equipment and activities was more positively accepted than what we initially expected. Although the attitude-behaviour gap must not be underestimated, this opening can be viewed as an evolution of lifestyles in some segments of the population. Governance and institutional arrangements are expected to play a critical role in supporting this evolution.The second ...

This contribution presents a user-friendly data reduction routine for Pitot probes based on widely available software with a fluid properties interface. The data reduction process rests on the general balance equations and the fluid database and calculation program REFPROP by NIST. In the corresponding calculation sheet, the user can easily select the fluid and manually or automatically insert the probe data and stagnation conditions of the measurement. A robust algorithm directly calculates the freestream Mach number and other flow and thermodynamic quantities. The new Pitot probe data reduction routine's accuracy is assessed through several test cases, including the subsonic and supersonic flow of dry air, Novec 649, and siloxane MM in the dilute and dense gas regime. For compressible non-ideal gas flows, it is found the classical Rayleigh-Pitot equation is systematically in error even in the dilute gas regime where relative deviations of more than 10 % were noticed. In the dense gas regime, the Rayleigh-Pitot equation fails dramatically in calculating the freestream Mach number, and errors larger than 60 % were observed.

Electricity distribution networks are commonly subject to supply interruptions and outages caused by faults. This dissertation focuses on medium voltage distribution networks, which typically consist of primary substations having multiple feeders along which secondary substations are located. When a permanent fault occurs on a segment (the part linking two consecutive secondary substations) of a distribution feeder, the faulted segment needs to be identified and isolated. Identifying the faulted segment can be realized through fault passage indicators. This is a straightforward task when the fault type is a short circuit, as these types of faults involve large currents. However, faulted segment identification for earth faults in non-effectively grounded medium voltage distribution networks has remained a challenge as the earth fault current in those networks is typically relatively small. Therefore, the main objective of this dissertation was to develop novel methods for locating single-phase earth faults in medium voltage distribution networks and validating them through simulations and real system measurements. After comprehensive review of state-of-the-art approaches presented in the literature, the dissertation proposes innovative methods for earth fault passage indication aimed at non-effectively grounded urban or rural distribution networks with radial feeders. The proposed methods are underpinned by a theoretical analysis based on the symmetrical components of the currents on a distribution feeder under an earth fault condition. The comparison of the sequence currents collected from various measuring points on the network forms the backbone of the methods. For practical implementation, current measurements need to be transferred to a central location for processing and decision making, but this can be done without accurate time synchronization. The proposed methods were developed and verified through simulations and empirical data. This work is a product of close collaboration between academia and ...

Upgrading of bio-oils for using them as transport fuel or as source for chemicals is a challenging task that has recently attracted a lot of attention. One of the most studied approaches in literature is hydrodeoxygenation, which is also the topic of this work. The light phase of a pyrolysis oil, produced in the bioliq® pilot plant in Karlsruhe, was treated with hydrogen (80 bar, pressure at room temperature) under mild hydrotreating conditions (250°C) in the presence of a catalyst. Different nickel-based catalysts were employed and were compared to Ru/C as benchmark. Nickel on different high surface area supports showed similar catalytic performance with inferior hydrogenation performance compared to Ru/C. Extensive quantitative 1H-NMR analysis was used for observing variations in the concentration of specific molecular functional groups in the products, while the distribution of the main elements (C, H, O) in the different phases was determined by elemental analysis and Karl Fischer titration. 1H-NMR and elemental analysis showed that the produced oil has less oxygen content respect to the original bio-oil. This is not only due to the hydrotreating reaction but also to the repartition of apolar compounds in the oil phase and of more polar ones in the aqueous phase. Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1164-1170