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Energy Extraction (energy + extraction)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Geothermal energy systems for major projects , design and construction / . Geothermieanlagen bei Großprojekten , Planung und Umsetzung

GEOMECHANICS AND TUNNELLING, Issue 5 2010
Dipl.-Ing.
Geothermal energy - Geothermie Abstract The application of geothermal energy has increased in the last couple of years in order to provide the heating or cooling demands of major projects. Open systems using groundwater directly can be used for geothermal energy extraction as well as closed systems with absorber pipes installed in underground structures. An accurate design, which considers the requirements of the energy consumer in particular but also the subsoiland groundwater conditions, the foundation concept and the building structure, as well as project-specific technical, legal and economic conditions, is required for economically efficient application. Diligent supervision is necessary during the construction stage to avoid any damage to absorber pipes, which could result in loss of performance. Zur Deckung des Heiz- oder Kühlbedarfs bei Großprojekten wird in den letzten Jahren vermehrt auf eine Erdwärmenutzung gesetzt. Dabei kommen sowohl offene Systeme wie eine direkte Grundwassernutzung als auch geschlossene Systeme mit Absorberleitungen in erdberührten Bauteilen zur Anwendung. Für eine wirtschaftliche Umsetzung bedarf es zunächst einer sorgfältigen Planung, wobei insbesondere die Anforderungen des Nutzers, die Untergrund- und Grundwasserverhältnisse, das Gründungskonzept einschließlich der Gebäudestruktur sowie projektspezifische technische, rechtliche und wirtschaftliche Randbedingungen zu berücksichtigen sind. In der Bauphase ist für eine plangemäße Umsetzung mit besonderer Sorgfalt vorzugehen, um Beschädigungen der Absorberleitungen und somit Leistungsminderungen zu vermeiden. [source]

Integrating electrical and aerodynamic characteristics for DFIG wind energy extraction and control study

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 12 2010
Shuhui Li
Abstract A doubly fed induction generator (DFIG) wind turbine depends on the control of the system at both generator and turbine levels, and the operation of the turbine is affected by the electrical characteristics of the generator and the aerodynamic characteristics of the turbine blades. This paper presents a DFIG energy extraction and control study by combining the two characteristics together in one integrative environment to examine various factors that are critical for an optimal DFIG system design. The generator characteristics are examined for different d-q control conditions, and the extracted power characteristics of the turbine blades versus generator slip are presented. Then, the two characteristics are analyzed in a joint environment. An integrative study is conducted to examine a variety of parametric data simultaneously for DFIG maximum wind power extraction evaluation. A close-loop transient simulation using SimPowerSystem is developed to validate the effectiveness of steady-state results and to further investigate the wind energy extraction and speed control in a feedback control environment. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Analysis of a small horizontal axis wind turbine performance

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2001
Ahmet Z. Sahin
Abstract A small-scale horizontal axis wind turbine capable of producing 100 W of rated power has been designed and tested using a low-speed wind tunnel. Power output from the wind turbine was calculated through measurements of the electrical current from a 12 V DC generator. Annual energy extraction from this wind turbine shows that a number of potential applications are possible especially in the remote areas where extension of power grid is not feasible. Copyright © 2001 John Wiley & Sons, Ltd. [source]