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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Tepelné čerpadlo v trivalentním systému vytápění / Heat pump in multivalent heating system

Šedý, Martin January 2008 (has links)
Thesis deals with the usage of energy from recoverable resources. Theoretical part of thesis includes the description of the utilisation of heating pumps, solar radiation and biomass. The real status of the implementation is described in the second part of the thesis. Last part of the thesis contains the energy and economy valuation of real implementation.
42

Studie turbiny s vířivým oběžným kolem / Study of turbine with side channel runner

Jandourek, Pavel January 2012 (has links)
This thesis deals with proposal of constructional solving turbine with side channel. Basis for the design is lossy characteristics of the valve. The intention is to replace hydraulic closures by turbine with side channel runner. Hydraulic losses in the flow restriction in turn replaced by the electricity generation in the comparable characteristics of valve and turbine.
43

Posouzení energetické náročnosti objektu pro vzdělávání / Energy consumption and energy supply of educational building

Šperka, Radim January 2014 (has links)
This thesis deals with the processing of an energy audit of the selected building for daily education. The target of this thesis is an evaluation of the current situation of the building, it means the evaluation of the thermal-technical qualities and energy consuption. For the initial state new measures will be suggested to reduce the energy consuption. One of the measures will be a proposal for an alternative way of supplying of the thermal energy, using the thermal pump. These suggested saving measures will be evaluated, including basic economic analysis.
44

ENERGIBERÄKNINGARS TRÄFFSÄKERHET : EN STUDIE AV SVENSKA MILJÖCERTIFIERADE FLERBOSTADSHUS / THE ACCURACY OF ENERGY CALCULATIONS : A STUDY OF SWEDISH RESIDENTIAL BUILDINGS WITH ENVIRONMENTAL CERTIFICATE

Danielsson, Malin, Gunnarsson, Susanne January 2022 (has links)
Detta examensarbete gjordes i samarbete med Riksbyggen där träffsäkerheten hos energiberäkningar i Miljöbyggnad studerades. Beräkningarna för den kommande energianvändningen jämfördes med mätningarna när byggnaden är i bruk. Vi ställde oss frågan om betygen i Miljöbyggnad påverkades av en avvikande energianvändning.Syftet med studien var att ge en bredare kunskap om miljöcertifierade byggnaders verkliga och förväntade energianvändning. Detta gjordes genom att identifiera och statistiskt säkerställa differenser mellan beräknad och uppmätt uppvärmnings-, varmvattens- och fastighetsenergi. Metoden som användes var en kartläggning av sekundärdata ur dokumentation från certifieringsprocessen för 116 stycken byggnader. Avvikande indikatorbetygs påverkan på områdes- och byggnadsbetyget i Miljöbyggnad undersöktes.Studien visade att det är svårt att beräkna - hälften av objekten hade en differens på mer än 10% och den årliga energianvändningen ökade i genomsnitt med 3,7 kWh/m2. Störst avvikelse hade uppvärmningsenergin med 9,7 kWh/m2, med sänkta indikatorbetyg till följd. En fjärdedel av dessa hade en vanskligt liten marginal till betygsgränsen.38% av flerbostadshusen hade ett förändrat betyg hos indikatorn för energianvändning, varav 4% fick ett bättre betyg medan 34% fick ett sämre betyg. En tredjedel av de med försämrade betyg fick sänkta områdesbetyg för energi, men behöll trots det byggnadsbetyget i Miljöbyggnad. Lagstiftande krav på minskad energianvändning fick delvis önskad effekt, samtidigt som differensen mellan beräkning och mätning ökade. Revideringar av indikatorbetyg tyder på att installationssystemen för ventilation och uppvärmningsenergin inte var korrekt intrimmade och behöver följas upp. I vilken omfattning man avsiktligt eller oavsiktligt frångått de ursprungliga planerna under byggprocessen lämnas till mer djupgående studier att ta reda på. / This thesis was created with collaboration from Riksbyggen where the accuracy of energy calculations in Miljöbyggnad were studied. Calculations for the upcoming energy use was compared with measurements of the energy of the building when in use. We asked ourselves whether the grades in Miljöbyggnad were affected by a deviating energy use.The purpose of this thesis was to provide a wider knowledge of the actual and expected energy use of buildings with an environmental certificate. This was achieved by identifying and statistically ensuring differences between calculated and measured energy of heating, hot water and real estate use. The method used was a survey of secondary data from the documentation of the process of certification of 116 buildings. The impact of a deviating indicator rating on the field and building rating in Miljöbyggnad was investigated.The study showed that it is difficult to calculate – half of the buildings had a difference of more than 10% and the annual energy use increased by an average of 3,7 kWh/m2.The most significant deviation was the energy used for heating with 9,7 kWh/m2, with decreasing indicator ratings as a result. A quarter of these had a precariously small margin to the limit of the rating level.38% of the residential buildings had a changed rating of the indicator of energy use, whereof 4% got a higher rating and 34% got a lower rating. A third of the ones with lower ratings also got decreased ratings in the field of “Energi”, but nevertheless retained their overall building rating in Miljöbyggnad.Legislative requirements for reduced energy use partly had the desired effect, though at the same time, the differences between calculations and measurements increased. Revisions of indicator ratings suggests that installation systems of ventilation and heating were not properly tuned and needs to be adjusted. To which extent they intentionally or unintentionally abandoned the original plan during the construction process is left to more thorough studies to look into.
45

Komise pro kanalisování řek Vltavy a Labe v Čechách 1896 -1931 / The Commission for making the river Vltava and the river Labe in Bohemia navigable 1986 - 1931

Černá, Marcela January 2014 (has links)
The Commission for making the river Vltava and the river Labe in Bohemia navigable was founded in 1896 on the basis of a decree of the ministry of interior as the first water management office to be systematically engaged in making Czech rivers navigable by the canalization method. The Commission was headed by the vice-regent of the Kingdom of Bohemia to whom the members of state's and country's curia were subordinate. The executive section was represented by the central office, composed of the technical and administrative departments. Its activities were financed by two thirds by the Austrian state, one third was paid from the Czech country's treasury. After the establishment of the independent Czechoslovak republic, both curias were dissolved and the Commission was put under the control of the ministry of public works. The president of the country's political administration was appointed as the head of the Commission. The competence of the Commission was step by step extended from the initially entrusted task of making the river Vltava and the river Labe in the division Prague - Ústí nad Labem navigable also to making the river Vltava in Prague navigable as well as to the adaptation of the Holešovice port in Prague to a modern trade port and to drawing up studies on the utilization of water...
46

Critical Transmission Sectors of Energy-Water-GHG Nexus / Critical Transmission Sectors of Energy-Water-GHG Nexus

Wang, Xuechao January 2020 (has links)
Využití vody, spotřeba energie a emise skleníkových plynů (GHG) jsou rozhodujícími ukazateli a do značné míry souvisí s udržováním nebo dosahováním environmentální a sociální udržitelnosti. Tato práce prezentuje vyvinuté metodiky. Představuje také provedené případové studie, které prozkoumaly a identifikovaly Water-Energy-GHG Nexus (WEGN) z pohledu dodavatelského řetězce. Pro analýzu a návrh sítě WEGN jsou navrženy tři metodiky, které jsou založeny na nové aplikaci a integraci modelu vstup-výstup (IO), geografického informačního systému (GIS) a sítě dodavatelského řetězce (SCN), a zároveň řeší výzvy, které dříve neumožňovali praktické implementace. Použitelnost těchto metod je prokázána třemi komplexními případovými studiemi zaměřenými na odvětvovou environmentální účinnost, regionální environmentální účinnost a kritické přenosy WEGN. Mezi mé příspěvky v této oblasti patří: i. Nový nástroj pro hodnocení založený na IO pro identifikaci regionální environmentální účinnosti z hlediska WEGN, zejména pro regiony, které jsou úzce propojenyobchodem. ii. Pokročilá integrace metodik GIS a IO (GIS-IO) za účelem odhalení a mapování sítě WEGN, sledování kritických meziregionálních a sektorových toků WEGN, vyjasnění regionálních, odvětvových a celosvětových vzorců sítě WEGN a určení souvisejících výhod pro různé regiony. iii. Efektivní metoda hodnocení založená na IO a SCN pro kvantifikaci sektorových koeficientů WEGN. Navrhované metodiky, s podporou sady komplexních základních rovnic, transformují komplikované výzvy identifikace a analýzy sítě WEGN do snadno srozumitelného formátu, z čehož vznikají robustní řešení pro zlepšení posuzování environmentální udržitelnosti a zmírnění environmentálních tlaků. Například v jedné z případových studií ukazují výsledky nového přístupu GIS-IO zjevné rozdíly mezi různými zeměmi v rámci EU27, mezi různými sektory a také pokud srovnáme EU27 jako blok zemí, s ostatními státy světa. Analýza ukázala, že země EU27 přispěly o 1.4 Gt nižšími emisemi CO2, o 64.5 Gm3 menší spotřebou vody a 4.9 × 104 PJ nižší spotřebou energie ve srovnání se zbytkem světa, přičemž generovaly ekvivalentní ekonomickou produkci. To má dramatický dopad na globální prostředí. Největší úspěch v CWE mezi zeměmi EU27 měly Německo, Francie a Itálie. Práce doporučuje, aby EU27 poskytovala více technické podpory zemím, které těchto výsledků nedosahují, aby se zvýšila účinnost využívání zdrojů.
47

Využití odpadní vody v EDU pro vytápění / Use of Waste Water in Nuclear Power Dukovany for Heating

Bohůn, Vojtěch January 2010 (has links)
This diploma thesis deals with various ways of energetically advantageous utilization of waste heat produced by industrial technologies. The focus of the diploma thesis is both to provide an overview of different ways and places of origin of waste heat in industrial technologies and of its possible reutilization, to suggest a concrete air heating system using waste heat and to propose a long-distance hot water pipe which supplies hot water pipe system with energy. First, technologies producing waste heat and some ways of regressing of heat in such technologies are theoretically described. Second, the equipment for transferring of heat and for adjustment of thermal energy parameters is described. A special focus is put on water supplies of the Nuclear Power Plant Dukovany and some selected parts of its secondary circuit, which is waste heat collected from. The analysis is supplemented by a calculation of theoretical quantity of waste heat. The aim of the calculation is to determine whether waste heat can be a source of energy for heating. Then, a current system of heating of three selected buildings in the area of the Nuclear Power Plant Dukovany is briefly described. Based on the gained knowledge, a project of air heating with two heat pumps type water – water, a heat receiver preparing warm service water and three recuperative units for preheating of fresh heating air is designed. The selection of main parts of the air heating is amended by a calculation of purchase costs and electric energy consumption. After that, the focus is placed on choice of type of hot water pipe – its trace is stated and an indicative estimation and a thermal-conditions calculation in the hot water pipe are made. The preliminary calculation serves as a source of information for a final project of air heating and calculation of changes of temperatures longwise the hot water pipe. The project contains also a calculation of pressure losses and an analysis of economical questions concerning hot water pipes. In conclusion, the results of project of air heating and hot water pipes are summarized.
48

Posouzení možnosti připojení kogenerační výrobny 138 MW v Prostějově / The assessment of connectivity 138 MW combined heat and power plant in Prostějov

Vacek, Tomáš January 2011 (has links)
The goal of this project is to test the possibility to connect the Cogenerational generation of power 138 MW (still in the development stage) to the control room 110 kV in Prostejov production. This merge would product the electrical energy as well as the heat energy for all local area. In this dissertation we will be considering the solution of the steady state (stationary state) of system with the voltage level of 110kV, as well as the influence of the generation of power on this system, there by the suggesting a connection. The Congenerational production indicates higher effectiveness in the transformation of energy during primary production process due to the production of heat energy as well as the electrical energy from the primary power sources. In our country, as well as around the world, commonly used fuels are fossil fuels- coal, crude oil, and gas. As the demand for energy grows, those supplies are slowly running out. Not to mention that those fuels have a negative environmental impact. They are a source of carbon, which causes damage to the atmosphere and leads to global warming. Power plants which do not produce carbon are much safer for the environment, and much more productive. However, the residue of this energy is challenging to dispose of. Nuclear energy has common attributes with renewing the sources of energies that are extremely friendly to our environment. Nuclear power plants also produce enough energy and with the usage of Fourth generation reactors, they will be able to recycle the nuclear fuels. Today, more importance is put on renewing sources which are more gentle for the environment. In the near future, CEZ Company, the largest producer of electric energy is planning to use water energy. Water energy comes from water plants or dams. Other ecological forms of energy include geothermal and solar energies. These two types of energy are not as applicable for our geographical position. Geothermal energy is commonly used on islands where there is an abundance of natural hot springs. The most discussed source of energy is bioenergy. It uses natural wood sources, recycled wood products, and applies bioenergy as a main source for thermal power plants.
49

Environmental System-of-Systems Engineering for integrated Nexus design - Developing participatory approaches to design decision making processes in complex human-nature-technology systems

Heitmann, Fabian 11 November 2020 (has links)
In this thesis, a conceptual framework and related methodological approaches for complex system design are developed and tested. The approaches are based on insights from the fields of Systems Engineering (SE) and System-of-Systems Engineering (SoSE), as well as Natural Resources Management (NRM). The focus of this thesis is on: 1) the development of the System-of-Systems Design Framework “FRESCO”, 2) the development of a methodological framework for participatory systems design, 3) the application of the framework in two case studies, and 4) the development of an evaluation scheme to qualitatively measure the effectiveness of the methodological framework. The overall objectives of this doctoral dissertation are to highlight synergies between SE and NRM and to develop a methodological framework for designing decision making processes in a human-nature-technology context. The complexity of coupled and complex adaptive systems (CAS) such as the Water-Energy-Food Nexus (WEF-Nexus) and sustainability strategies, influences the design of decision-making processes and strategy building. Integrated process design which is promoted by the developed frameworks can assist in such tasks on an urban, regional, and national level.
50

Water Ties: Towards a Relational Understanding of Water Governance Networks in Tanzania and Ethiopia

Stein, Christian 10 July 2019 (has links)
This interdisciplinary thesis studies the diverse multi-stakeholder networks that are constitutive of contemporary water governance. It examines collaborative governance networks from a relational perspective in two case study watersheds in Tanzania and Ethiopia. Collaborative and networked governance approaches are increasingly promoted to address complex water challenges, but relatively little is known about how the everyday collaborative relationships (i.e. collaboration practices) among the multiple actors involved in the development, management and use of water, shape contemporary water governance processes. In this thesis, I advance, based on intensive fieldwork data collection, a conceptual and methodological framework for studying collaboration networks pertaining to watershed management. I examine local collaborative governance networks in two watersheds, in Ethiopia and Tanzania, from a relational perspective, using complementary qualitative and quantitative social network research methods. The thesis explores the opportunities and limitations of such collaborative governance networks in their concrete functioning, thereby contributing to a more context-sensitive, and nuanced, understanding of the role of governance networks and collaborative governance approaches in the management of water and related resources.

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