Sökning: "ground-source"

Visar resultat 11 - 15 av 27 avhandlingar innehållade ordet ground-source.

1. 11. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes

   Författare :José Acuña; Björn Palm; Jeffrey Spitler; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Borehole heat exchangers; Distributed Thermal Response Test; Ground Source Heat Pumps; Coaxial; U-pipe; Multi-pipe; Pipe-in-pipe; Multi-chamber; Groundwater; Thermosyphon; SRA - Energy; SRA - Energi;

   Sammanfattning : U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs. LÄS MER

3. 12. Building Energy Efficiency - Policy, learning and technology change

   Författare :Bernadett Kiss; Internationella miljöinstitutet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Policy learning; technology change; energy efficiency; building;

   Sammanfattning : Experience shows that energy efficiency improvements are the most cost-effective path to meeting global energy challenges. To promote energy efficiency, various policy instruments have been in place since the 1970s. LÄS MER

4. 13. Frosting and Defrosting of Air-Coils

   Författare :Per Fahlén; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat pump; defrost; air-coil; air-source; control; frost; optimized;

   Sammanfattning : Experience indicates that air-source heat pumps have more operating problems than ground-source heat pumps. One major factor pertains to the effects of frosting and the subsequent need for defrosting. This thesis reviews previous research and practical experience and presents novel experimental facilities to investigate the process of frosting. LÄS MER

5. 14. Restructured district heating price models and their impact on district heating users

   Författare :Jingjing Song; Björn Karlsson; Fredrik Wallin; Hailong Li; Heimo Zinko; Mälardalens högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; district heating; restructured price model; price model survey; pricing strategy; consumption profile; consumption pattern; alternative cost; Energy- and Environmental Engineering; energi- och miljöteknik;

   Sammanfattning : District heating (DH) is considered to be an efficient, environmentally friendly and cost-effective method for providing heat to buildings, since electricity is usually co-generated in biomass fuelled combined heat and power (CHP) plants. This gives it an important role in the mitigation of climate change. LÄS MER

7. 15. Thermally Conductive High-Density Polyethylene Composites for Ground Heat Exchangers

   Författare :Adib Kalantar Mehrjerdi; Högskolan i Borås; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High-density polyethylene; talc; thermal conductivity; thermal diffusivity; thermal stability; melt rheology; oxidation induction time; α relaxation; strain hardening;

   Sammanfattning : Today, the energy used for the heating and cooling of offices, shopping centres, schools, residential areas, andother buildings is as large as 50% of the total energy consumption in the world. The climate change, globalwarming, and environmental issues have forced high requirements for energy efficiency and clean energyproduction in buildings. LÄS MER