Sökning: "electric heating"

Visar resultat 1 - 5 av 130 avhandlingar innehållade orden electric heating.

1. 1. Comparative Assessment of Fuel-Based Systems for Space Heating

   Författare :Åsa Karlsson; Miljö- och energisystem; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Energiforskning; Energy research; cogeneration; district heating; electric heating; external cost; carbon dioxide mitigation; detached houses; fossil fuels; Energy systems; bioenergy;

   Sammanfattning : Replacing fossil fuels by biofuels and increasing energy efficiency are often considered to be options for reducing the net emission of greenhouse gases. This thesis presents the results of analyses of energy efficiency, emission and cost of whole energy system chains, from the natural resource to the end user when heating detached houses in a Swedish context. LÄS MER

3. 2. Effektivisering av pump- och fläktdrifter i byggnader. Elanvändning och systemlösningar

   Författare :Caroline S Markusson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; damper; efficiency; electric energy; authority; demand; control; variable speed; valve; heating; cooling; fans; electric motors; ventilation; pumps;

   Sammanfattning : In this licentiate work the energy savings potential by more efficient pump and fan operation in buildings has been examined. The national savings potential in Sweden has been estimated based on available statistics and on information gained in a limited inventory. The estimated energy use for pump operation in residential and commercial (i.e. LÄS MER

4. 3. Process Control and Simulation of Ferromagnetic Strip in the Power Transformers and Electrical Machines Applications : Electric power systems

   Författare :Kourosh Mousavi Takami; Jafar Mahmoudi; Örjan Danielsson; Mihai Nicolescu; Mälardalens högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strip; electrical machines; transformer; cold rolling mills; process; automation; control; Band; elektriska maskiner; transformatorer; kallvalsningsverk; processautomation; reglerteknik; Electric power engineering; Elkraftteknik; Energy- and Environmental Engineering; energi- och miljöteknik;

   Sammanfattning : This thesis investigates optimization of the control of electrical and thermal equipment by using FEM and CFD modeling in combination with dynamic simulation models. The thesis focuses on the production of electrical strips and the control system with the aim of reducing losses and improving magnetic properties. LÄS MER

5. 4. Low-temperature District Heating : Various Aspects of Fourth-generation Systems

   Författare :Helge Averfalk; Sven Werner; Brian Elmegaard; Högskolan i Halmstad; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; District heating; low temperature; three-pipe systems; 4GDH-3P; District heating; low temperature; three-pipe systems; 4GDH-3P;

   Sammanfattning : With decreasing heat demand and less availability of high-temperature heat supply in future energy systems, the current district heating systems may experience increased competition on the heat market. A viable option to mitigate increasing competition is to operate systems with lower temperature levels, and the most conceivable way to achieve lower temperature levels is to decrease return temperatures. LÄS MER

7. 5. Auroral Electric Fields From Satellite Observations and Numerical Modelling

   Författare :Tomas Karlsson; KTH; []
   Nyckelord :Satellite measurements; electric fields; ionosphere; magnetosphere; diverging electric fields; downward current region; black aurora; westward travelling surge; auroral bulge; subauroral ion drifts SAID ; subauroral electric fields SAEF ; mid-latit; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : This thesis is about electrodynamics of thehigh-latitude/auroral region of near-Earth space. The work ismainly based on electric field measurements made by the doubleprobe instrument on the Freja satellite at altitudes ofapproximately 800-1700 km, together with measurements fromother instruments on the same satellite, and ground-basedinstrumentation. LÄS MER