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Stockholm, Sweden

Vattenfall is a Swedish power company, wholly owned by the Swedish government. Beyond Sweden, the company generates power in Denmark, Finland, Germany, the Netherlands, Poland, and the United Kingdom.The company's name is Swedish for "waterfall", and is an abbreviation of its original name, Royal Waterfall Board . Wikipedia.

The MTO-E method for event investigation is described in the light of almost 20 years of usage in the Swedish nuclear industry. Various problems are addressed in the context of the method, e.g. accident models, causality, the use of the barrier concept, the meaning of safety culture, and the process of going from problem identification to problem solving. It is argued that future applications of in-depth investigations should focus more on (innovative) methods when suggesting remedial actions as a consequence of information derived from event investigations. © 2009 Elsevier Ltd. Source

Lidenholm J.,Vattenfall | Lundin U.,Uppsala University
IEEE Transactions on Energy Conversion | Year: 2010

Four standard test proceduresthe three phase short-circuit test , the field decrement test, the slip test, and the applied voltage testfor estimation of synchronous generator parameters have been implemented in a time-stepping finite-element software. In this paper, the main features of the implementation and the postprocessing of data are described. The validity of the application is demonstrated by comparison with test results from the commissioning of a large hydropower generator. The method is shown to be effective in estimating most parameters. Better representation of the exciter and the interpole connections of the damper circuit is believed to enhance the compliance even further. © 2006 IEEE. Source

Hirth L.,Vattenfall | Hirth L.,Potsdam Institute for Climate Impact Research
Energy Economics | Year: 2013

This paper provides a comprehensive discussion of the market value of variable renewable energy (VRE). The inherent variability of wind speeds and solar radiation affects the price that VRE generators receive on the market (market value). During windy and sunny times the additional electricity supply reduces the prices. Because the drop is larger with more installed capacity, the market value of VRE falls with higher penetration rate. This study aims to develop a better understanding on how the market value with penetration, and how policies and prices affect the market value. Quantitative evidence is derived from a review of published studies, regression analysis of market data, and the calibrated model of the European electricity market EMMA. We find the value of wind power to fall from 110% of the average power price to 50-80% as wind penetration increases from zero to 30% of total electricity consumption. For solar power, similarly low value levels are reached already at 15% penetration. Hence, competitive large-scale renewable deployment will be more difficult to accomplish than as many anticipate. © 2013 Elsevier B.V. Source

Amand L.-E.,Chalmers University of Technology | Kassman H.,Vattenfall
Waste Management | Year: 2013

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700°C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12MWth circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel. © 2013 Elsevier Ltd. Source

The present invention relates to a method for determining at least one gas condition at a location in a combustion chamber of a power plant or a combined heat and power plant by means of a laser pulse. The method comprises emitting (S

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