High-Temperature Heat Pump for Wellness Applications Using CO2 as a Refrigerant

Building technology recently has been affected by great innovations to reduce energy demand and to enable self-sufficient operation. To test innovations and prove practicality, EMPA has built a research building called NEST, where different demonstration projects from the building industry can be integrated and scientifically monitored. Furthermore, the sector of wellness applications shows significant potential for improving energy efficiency. Usually, spa facilities such as saunas and steam baths are based on direct electric or fossil heating which is extremely energy intensive and results in high operating costs. In order to establish a more energy efficient technology to provide heat to wellness areas, the present work proposes the usage of a high temperature heat pump with CO2 as a refrigerant. Carbon dioxide is currently favored by many heat pump applications due to the demand for low-GWP refrigerants with non-toxic and non-flammable properties. High-temperature heat pumps with CO2 as a refrigerant are already available on the market and reach supply temperatures typically up to 100 °C. Wellness applications require temperatures up to 130 °C on the supplier side, which requires new system design. On the consumption side, the heat will be used on a wide variety of temperature levels considering different saunas, showers and space heating. In this context, a stratified storage system ensures the heat output on the desired temperature level. Therefore, the heat exchanger unit as well as the operating range of the heat pump are the major challenges. In Coorporation with Scheco AG, a new CO2 refrigerant system has been designed and set up as a part of EMPA research building by means of a pilot installation including different saunas, steam bath and showers. Measurements will be performed as soon as possible to start the optimization process of the system

Simulation of a VRF system applied in elcectric buses in Taiwan

Based on test data from an electric bus manufacturer, HVAC systems will consume nearly 30% of the available energy in fully electrically operated public transport buses, which heavily decreases the bus mileage. Therefore, improvements for the bus HVAC system structure are needed. In contrast to conventional electric bus HVAC systems, a VRV (variable-refrigerant-volume) system will be simulated as HVAC system. The compressors provide adequate power depending on the requirements from the different heat exchanger units inside the bus cabin. This system will provide either cooling or heating capacity depending on the needs of the target space. Therefore, the energy consumption of the compressors will be reduced This paper will present a dynamic EES simulation model of a VRV system applied in an electric public transportation bus. Goal of this simulation is, to simulate and design the specifications of the VRV HVAC system with given system performance requirements. The bus model and the simulation results will be described in detail in this publication. This project has been developed in collaboration between the Automotive Research and Testing Center of Taiwan (ARTC) and the University of Applied Sciences in Buchs (NTB)

Prävalenz der Eisenmangelanämie in einer populationsbasierten Kohorte bei Patienten mit chronisch-entzündlichen Darmerkrankungen

Hintergrund: Obwohl die allgemeine Datenlage für die Prävalenz der Anämie, aber auch für die der Eisenmangelanämie bei CED-Patienten gut ist, sind populationsbasierte Daten zu diesem Thema immer noch rar. Kulnigg et al. [7] wiesen schon 2006 auf die Notwendigkeit populationsbasierter Studien hin, um die Prävalenz der Anämie exakter bestimmen zu können. Da die letzten Prävalenzdaten für die Anämie bei CED-Patienten in Deutschland sechs Jahre alt sind und populationsbasierte Studien zur Prävalenz der Eisenmangelanämie bei CED-Patienten in Deutschland bislang nicht veröffentlicht sind, war das Ziel dieser Arbeit, aktuelle Prävalenzdaten in einer prospektiven populationsbasierten Kohorte zu ermitteln. Methoden: Alle CED-Patienten aus der Region Oberpfalz, bei denen vom 1. Januar 2004 bis einschließlich 21. Januar 2009 eine Anämie zum Zeitpunkt der Erstdiagnose oder spätestens ein Jahr danach diagnostiziert wurde, wurden in diese Studie aufgenommen. Von den Patienten wurden demographische Daten wie Alter und Geschlecht sowie klinische Daten, wie kleines Blutbild und Eisenstatus zum Zeitpunkt der Erstdiagnose, ein Jahr später und zum letzten Beobachtungszeitpunkt erhoben. In einem Telefoninterview wurden zusätzlich Daten bezüglich einer abgeschlossenen Eisensubstitutionstherapie sowie Dauer und Verträglichkeit der Therapie erfragt. Ergebnisse: Von 279 CED-Patienten mit verfügbarem Hb-Wert bei Erstdiagnose konnte bei 90 Patienten (60 MC, 26 CU, 4 CI) eine Anämie gesichert werden. Davon hatten 68 Patienten eine Anämie bei Erstdiagnose, die restlichen 22 Patienten entwickelten eine Anämie erst ein Jahr später. Die Prävalenz der Anämie bei Erstdiagnose war 24 % (68/279), ein Jahr später 16 % (44/279) und zum letzten Beobachtungszeitpunkt 7 % (19/279). Die Prävalenz der Eisenmangelanämie war 9 % (26/279) bei Erstdiagnose, 10 % (28/279) ein Jahr später und 6 % (18/279) zuletzt. Festzuhalten ist, dass nur bei 46 % der Patienten mit gesicherter Anämie bei Erstdiagnose ein Eisenstatus erhoben wurde. Von allen identifizierten Patienten mit Eisenmangelanämie wurden 44 % mit Eisen behandelt, davon 37 % mit einem oralen und 7 % mit einem intravenösen Präparat. 43 % aller Eisenmangelanämiepatienten setzten die orale Therapie maximal drei Monate fort. 27 % brachen die Therapie nach vier Wochen ab. 70 % aller Eisenmangelanämiepatienten gaben eine gute Verträglichkeit für das orale Eisenpräparat an, 30 % eine mittelmäßige bis schlechte Verträglichkeit. In 22 % der Fälle waren die Beschwerden gastrointestinaler Art. Bei der Hälfte der Patienten besserten sich die Anämiesymptome Abgeschlagenheit und chronische Müdigkeit nach Eisenapplikation. Im Verlauf bewirkte bei 31 % der Patienten die Eisentherapie (oral oder i. v.) einen Hb-Anstieg, bei 47 % stieg der Hb-Wert trotz Therapie (oral oder i. v.) nicht an. Schlussfolgerung: Die Prävalenzrate für die Anämie bei CED scheint seit den 70er Jahren tendenziell rückläufig zu sein, verglichen mit den aktuell veröffentlichten Daten. Für die Eisenmangelanämie trifft diese Entwicklung seit den 90er Jahren überwiegend ebenfalls zu. Festzuhalten bleibt dennoch, dass die Erfassung des Eisenstatus heutzutage nicht konsequent verfolgt wird und dies letztendlich in einer insuffizienten Eisenversorgung der Patienten resultiert. Ebenso scheinen intravenös verabreichte Eisenpräparate trotz ihres guten Sicherheitsprofils sehr zurückhaltend appliziert zu werden. Orale Eisenpräparate sind derzeit trotz ihres problematischen Sicherheitsprofils, ihrer Verträglichkeit und der fraglichen Compliance der Patienten weiterhin die erste Wahl bei CED-assoziierter Anämie

Fluiglass - Façade Elements for Active Solar Control for High-Rise Buildings

A new facade type, called fluidglass, is under development for new buildings as well as to retrofit existing buildings. This new facade allows increasing the energy efficiency of the building as well as the comfort of people inside. The system works as a shading device, as a solar collector for supporting the hot water production and as cooling or heating device. Core of the system is a fluidized glass facade that controls the heat flux as well as the solar radiation through the facade. One or two fluid-filled layers are set into the glass facade. These fluid layers regulate the energy flows within the facade by being adjustable in transmittance. The outer layer is mostly for absorbing the solar radiation and the inner layer is for controlling the inner room temperature. Both layers are thermally separated by an insulation glass. The energy transmission as well as the lighting of the rooms can be regulated by pigmenting the fluid. For cooling and heating purposes the complete facade is available for heat exchange. So, only small temperature differences between room and supply temperature are required leading to high efficiency of A/C and heat pumping equipment. This paper will present the schematic and idea of fluidglass and the theoretical background. Furthermore, some simulation results about the fluid temperatures and the possible energy savings in buildings will be shown

High Prevalence but Insufficient Treatment of Iron-Deficiency Anemia in Patients with Inflammatory Bowel Disease: Results of a Population-Based Cohort

Background. Iron-deficiency anemia is described to be a common problem in patients with inflammatory bowel disease (IBD), which is frequently associated with a reduced quality of life. Therefore, the aim of this study is to assess the prevalence of iron deficiency anemia in a population-based cohort at time of first diagnosis and during the early course of the disease. Methods. As far as available, lab values of patients registered in the population-based “Oberpfalz cohort” were screened. In anemic patients, we further investigated all laboratory results to differentiate between iron deficiency and other reasons for anemia. All patients with any kind of anemia were interviewed separately according to symptoms of iron-deficiency anemia and administration of iron. Results. In total, we evaluated hemoglobin values of 279 patients (183 Crohn's disease, 90 ulcerative colitis, and 6 indeterminate colitis). Lab data which allowed further differentiation of the type of anemia were available in 70% of anemic patients, in 34.4% values of iron, ferritin and transferrin saturation had been measured. At time of first diagnosis, an iron-deficiency anemia was diagnosed in 26 of 68 patients with anemia (38.2%, 20 CD, 4 UC, and 2 IC patients), but only 9 patients (34.6%) received subsequent iron therapy. After one year, 27 patients were identified to have an iron-deficiency anemia (19 CD, 8 UC), 20 of them were treated with iron (71.4%). Of 9 patients with proven iron-deficiency anemia at time of first diagnosis and subsequent administration of iron, 5 (55.5%) had iron-deficiency anemia despite permanent treatment after one year. In total, 38 patients (54.3%) did not receive any iron substitution at all despite of proven iron-deficiency anemia, and only 13 patients of 74 patients were treated with intravenous iron (17.6%). Conclusion. We found a high prevalence of iron-deficiency anemia at different points during the early course of disease in this population-based cohort of IBD patients. Surprisingly, only in one-third of patients with proven anemia, further diagnostic approach was undertaken. Even patients with diagnosed iron-deficiency anemia were infrequently and inconsequently treated with iron preparations, despite the high impact on quality of life