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Das Passivhaus Institut hat eine große Anzahl genutzter Passivhäuser in Europa messtechnisch ausgewertet und konnte nachweisen, dass der Heizwärmebedarf neu gebauter Passivhäuser im Bereich von 15 kWh/m2a liegt, was nur 10-20% des Heizwärmebedarfs des Green Building oder anderer Energiesparstandards für Gebäude in China entspricht. Mit dem Passivhaus können den Heizwärmebedarf und die CO2-Emissionen in China erheblich gesenkt werden, was für die chinesische Regierung und Gesellschaft von großer Bedeutung ist. Folglich hat China im Zeitraum 2016-2020 mehr als 10 Millionen Quadratmeter Niedrigstenergiegebäude (Passivhäuser) gebaut und wird bis 2025 weitere 50 Millionen Quadratmeter errichten. Daher ist die Hauptmotivation dieser Arbeit, den Energieverbrauch von Passivhäusern in China zu untersuchen. Ziel ist, die Anwendbarkeit der Passivhausstandards unter Berücksichtigung der chinesischen Nutzergewohnheiten und klimatischen Besonderheiten zu validieren und ergänzende Vorschläge für die Anwendung zu unterbreiten. Für diese Arbeit wurden ein Passivhaus-Wohngebäude, ein Passivhaus-Bürogebäude und ein Green Building im Deutsch-Chinesischen Ökopark Qingdao, Nordchina, als Gegenstand der Untersuchung ausgewählt. Die angewandte Forschungsmethode gliedert sich im Wesentlichen in vier Schritte: a) Einrichtung eines Energieverbrauchsüberwachungssystems, um Energieverbrauchsdaten zu erhalten. b) Passivhaus-Planungspaket (PHPP), Therm und IBE sind Simulationswerkzeuge, die in dieser Arbeit zur Bewertung des Gebäudeenergieverbrauchs und der Wärmebrücken verwendet werden. c) Vergleich der Energieverbrauchsdaten des Passivhausgebäudes mit den simulierten oder entworfenen Energieverbrauchsdaten und schließlich d) Ermittlung der Unterschiede zwischen den beiden Datensätzen durch Analyse der Ursachen, um die Energieeffizienz des Gebäudes zu optimieren und aufzuwerten. Für die Studie wurden zunächst 3-jährige Betriebsdaten des 2016 errichteten Passivhauses-Bürogebäude ausgewertet. Das Gebäudesystem wurde gemäß den Daten des hohen Energieverbrauchs im Jahr 2017 in Betrieb genommen. Danach waren die Energieverbrauchsdaten in den folgenden zwei Jahren deutlich niedriger. Dies zeigt, wie wichtig die Inbetriebnahme der HVAC-Anlage für große öffentliche Passivhausgebäude ist. Die Analyse der Energieverbrauchsdaten und der innere Komfort-Parameter für die folgenden zwei Jahre ergab, dass der Heizwärmebedarf größer war als der simulierte Wert und der Kühlbedarf gut mit dem simulierten Wert übereinstimmte. Der innere Komfort des Gebäudes wurde das ganze Jahr über innerhalb des festgelegten Komfortbereichs gehalten. Zweitens wurde ein Passivhaus-Wohngebäude mit 36 Wohneinheiten, das im Jahr 2020 fertiggestellt wurde, messtechnisch begleitet. Erstmalig wurde ein Passivhaus-Wohngebäude in China messtechnisch ausgewertet. Während des Überwachungszeitraums ergab ein umfassender Vergleich der Entwurfs- und Konstruktionstechniken zwischen dem Passivhaus-Wohngebäude und einem benachbarten als Green Building gebauten Wohngebäude, dass im Passivhaus-Wohngebäude der Heizwärmebedarf im Vergleich zu dem Green Building Wohngebäude erheblich reduziert wurde, und es wurde vorgeschlagen, dass eine groß angelegte Förderung von Passivhäusern ein vorteilhafter Weg wäre, um Chinas Dual-Carbon-Ziele zu erreichen. Nach Abschluss der Überwachung zeigte die Analyse, dass der tatsächliche Heizwärmebedarf höher war als der vorhergesagte Wert, und dass der Primärenergieverbrauch und der innere Komfort den Passivhausstandards entsprachen. Die Gründe für den höheren Heizwärmebedarf sind 1) die Belegungsrate von nur 47% (17/36) im ersten Bezugsjahr und 2) Baufeuchte und Nutzerverhalten. Die Anwendbarkeit des Passivhausstandards in der kalten Klimazone und in der Küstenregion Nordchinas wurde an den beiden ausgewählten Passivhausgebäuden nachgewiesen. Die beobachteten Ergebnisse entsprechen im Wesentlichen den Passivhausstandards. Aufgrund des Nutzerverhaltens und der Belegungsrate entspricht ein Teil der Indikatoren nicht den Erwartungen, jedoch zeigt das Passivhausgebäude herausragende Vorteile in Bezug auf Energieeinsparung und Innenraumkomfort, verglichen mit den aktuellen Green Building oder anderen Gebäudeenergieeinsparungsstandards in China. German Passive House Institute has monitored many operating passive houses in Europe to prove that the heating demand of newly built passive houses is in the range of 15 kWh/m2a, which is only 10-20% of the heating demand of Green Building Standards or other building energy-saving standards in China. The passive house can significantly decrease heating demand and reduce CO2 emissions in China, these issues are of great concern to the Chinese government and society. Consequently, China built more than 10 million square meters of ultra-low energy buildings (passive houses) in 2016-2020 and will build another 50 million square meters by 2025. Hence, to do monitoring research on the energy consumption of passive houses in China is the main motivation of this thesis. The goal is to validate and supplement the applicability of the Passive House Standards considering the Chinese user habits and local climate characteristics. One passive house residential building, one passive house office building and one Green Building in Sino-German Ecopark Qingdao in northern China are selected for this thesis. The research method used is mainly divided into four steps: a) establishing an energy consumption monitoring system to obtain energy consumption data. b) Passive House Planning Package (PHPP), Therm, and IBE are simulation tools used in this thesis to evaluate building energy consumption and thermal bridges. c) comparing the energy consumption data of the passive house building in operation with the simulated or designed energy consumption data, and then d) finding out the differences between the two sets of data, through analyzing the reasons to achieve the purpose of improving and upgrading the energy efficiency of the building. Firstly, 3 years of operational data of the passive house public building built in 2016 were analyzed. The building system was commissioned through the data of high energy consumption in 2017. Then, the energy consumption data for the subsequent 2 years were significantly lower. It showed the importance of HVAC commissioning for large passive house public buildings. The analysis of the energy consumption data and indoor environment parameters for the subsequent 2 years revealed that the space heating demand was larger than the simulated value and the cooling demand matched the simulated value well. The building’s indoor environment was maintained within the set comfort range year-round. Secondly, a passive house residential building containing 36 apartments, which was completed in 2020, was selected for monitoring. This is the first time that a passive house residential building was monitored in China. During the monitoring period, a comprehensive comparison of the design and construction techniques between the passive house residential building and a neighbouring Green Building residential building revealed that the passive house residential building would significantly reduce space heating demand, and it was suggested that large-scale promotion of passive houses would be a beneficial way to achieve China's dual carbon goals. After the monitoring was completed, the analysis showed that the actual heating demand was higher than the predicted heating demand, and the primary energy consumption and indoor comfort met the passive house standards well. The reasons for the higher heating demand are 1) the occupancy rate of only 47% (17/36) in the first moving-in year and 2) initial wall moisture and user behavior. The applicability of Passive House standards in the cold climate zone and coastal region of northern China was proven in the selected two passive house buildings. The monitored results meet basically the passive house standards. Because of the user behavior and occupation rate, part of the indicators doesn’t meet expectations, however, the passive house building shows outstanding advantages in terms of energy-saving and indoor comfort, compared with other current Green Building Standards or other building energy-saving standards in China.

The International Atomic Energy Agency (IAEA), jointly with the World Health Organization (WHO), has operated a postal dosimetry audit program for radiotherapy centers worldwide since 1969. In 2017 the IAEA introduced a new methodology based on radiophotoluminescent dosimetry (RPLD) for these audits. The detection system consists of a phosphate glass dosimeter inserted in a plastic capsule that is kept in measuring position with a PMMA holder during irradiation. Correction factors for this holder were obtained using experimental methods. In this work these methods are described and the resulting factors are verified by means of Monte Carlo simulation with the general-purpose code PENELOPE for a range of photon beam qualities relevant in radiotherapy. The study relies on a detailed geometrical representation of the experimental setup. Various photon beams were obtained from faithful modeling of the corresponding linacs. Monte Carlo simulation transport parameters are selected to ensure subpercent accuracy. The simulated correction factors fall in the interval 1.005-1.008 (±0.2%), with deviations with respect to experimental values not larger than 0.2(2)%. This study corroborates the validity of the holder correction factors currently used for the IAEA audits.

A double-null configuration is being considered for the EU-DEMO, due to its potential benefits for power exhaust arising from the use of two active divertors and magnetically disconnected low- and high-field sides. Using systematic parameter scans in fluid simulations, we have investigated the divertor power exhaust in the EU-DEMO in a connected double-null configuration, and compared the edge plasma properties to those obtained in a single-null configuration under detached conditions anticipated for reactor operation. Neglecting drift effects and kinetic behaviour of the neutrals, no clear benefits of the double-null configuration could yet be identified for the radiation pattern and power mitigation on open field lines. Future work should address the aforementioned physics as well as the effect of the additional X-point on core radiation.

AbstractFundamental axes of variation in plant traits result from trade-offs between costs and benefits of resource-use strategies at the leaf scale. However, it is unclear whether similar trade-offs propagate to the ecosystem level. Here, we test whether trait correlation patterns predicted by three well-known leaf- and plant-level coordination theories – the leaf economics spectrum, the global spectrum of plant form and function, and the least-cost hypothesis – are also observed between community mean traits and ecosystem processes. We combined ecosystem functional properties from FLUXNET sites, vegetation properties, and community mean plant traits into three corresponding principal component analyses. We find that the leaf economics spectrum (90 sites), the global spectrum of plant form and function (89 sites), and the least-cost hypothesis (82 sites) all propagate at the ecosystem level. However, we also find evidence of additional scale-emergent properties. Evaluating the coordination of ecosystem functional properties may aid the development of more realistic global dynamic vegetation models with critical empirical data, reducing the uncertainty of climate change projections.

The production of synthetic methane using CO from flue gases and green hydrogen appears to be a promising way to combine the concepts of renewable energy, chemical storage, and utilization of CO. Recently, a new reactor configuration for catalytic methanation has been proposed, integrating sorption-enhanced methanation and chemical looping in interconnected fluidized bed systems. This configuration would ensure high methane yields while keeping good temperature control and low operating pressure. In this work, such novel system layout for the catalytic production of methane was combined with a calcium looping unit for CO capture from flue gases of a coal-fired power plant, and with a water electrolyzer sustained by renewable energy. The integrated layout offers a series of advantages deriving from the integration of different mass and energy flows of the different sections of the plant. The performance of this latter was assessed in terms of construction and production costs, as well as from an environmental point of view: a life cycle assessment was carried out to quantify the environmental impact of all process units. Results of the techno-economic analysis indicated that the production cost of methane is higher than that of natural gas (0.66 vs 0.17 EUR/Nm), but lower than that of biomethane (1 EUR/Nm). The largest impact on such costs comes from the PEM electrolyzer. The LCA analysis showed that the environmental performance is better in some categories and worse in others with respect to traditional scenarios. Again, the PEM electrolyzer appears to account for most of the environmental impacts of the process.