Sökning: "Uwe Zimmermann"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden Uwe Zimmermann.

  1. 1. Design, Processing and Characterization of Silicon Carbide Diodes

    Författare :Uwe Zimmermann; KTH; []
    Nyckelord :silicon carbide; diodes; high-voltage; dislocations; electronics;

    Sammanfattning : Electronic power devices made of silicon carbide promisesuperior performance over today's silicon devices due toinherent material properties. As a result of the material'swide band gap of 3. LÄS MER

  3. 2. Potential-Induced Degradation and possibilities for recovery of CuIn1-xGaxSe2 thin film solar cells

    Författare :Viktor Fjällström; Marika Edoff; Uwe Zimmermann; Thomas Walter; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Sammanfattning : The long-term performance of solar modules is of key importance to achieve profitable solar power installations. In this work, the degradation mechanism potential-induced degradation (PID) was investigated for CuIn1-xGaxSe2 (CIGS) thin film solar cells. LÄS MER

  4. 3. Year-round production of forest seedlings under LED lamps : Biological and energetic implications of indoor cultivation

    Författare :Marco Hernandez Velasco; Uwe Zimmermann; Anders Mattsson; Frank Fiedler; Johanna Riikonen; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Picea abies; Pinus sylvestris; year-round cultivation; forest seedlings; LED lamps; light quality; light quantity; daily light integral; adaptive lighting control; greenhouse integrated photovoltaics; agrivoltaics; seedling growth performance; short-day treatments; cold hardiness; light shock stress; Engineering Science; Teknisk fysik;

    Sammanfattning : Year-round cultivation of forest seedlings under light emitting diodes (LED) is a technology receiving increased attention from nurseries in the boreal forest regions. In these areas, the climate is characterized by strong seasonal fluctuations, resulting in short vegetation periods with narrow time windows for seedling transplanting and outdoor growth. LÄS MER

  5. 4. Solar Variability Assessment and Grid Integration : Methodology Development and Case Studies

    Författare :David Lingfors; Joakim Widén; Uwe Zimmermann; Eva Wäckelgård; Tobias Boström; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solar variability; Photovoltaics; Grid integration; GIS; Distributed generation; Engineering Science; Teknisk fysik;

    Sammanfattning : During the 21st century there has been a tremendous increase in grid-connected photovoltaic (PV) capacity globally, due to falling prices and introduction of economic incentives. PV systems are in most cases small-scale, installed on residential dwellings, which means that the power production is widely distributed and close to the end-user of electricity. LÄS MER

  7. 5. ZrN Back-Contact Reflectors and Ga Gradients in Cu(In,Ga)Se2 Solar Cells

    Författare :Sebastian Michael Schleussner; Marika Edoff; Tobias Törndahl; Uwe Zimmermann; Dieter Schmid; Uppsala universitet; []
    Nyckelord :Solar cells; CIGS; ZrN; three-stage process; multi-stage process; grading; SIMS; electrical modelling; NATURAL SCIENCES; NATURVETENSKAP; Teknisk fysik med inriktning mot elektronik; Engineering Science with specialization in Electronics;

    Sammanfattning : Solar cells constitute the most direct way of converting solar energy to electricity, and thin-film solar-cell technologies have lately been growing in importance, allowing the fabrication of less expensive modules that nonetheless have good power-conversion efficiencies. This thesis focuses on solar cells based on Cu(In,Ga)Se2, which is the thin-film technology that has shown the highest conversion efficiency to date, reaching 20. LÄS MER