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With an increasing share of regenerative wind and solar energy in electricity supply, the aspect of load flexibility will gain importance, i.e. there is an increasing need for buffer capacities and / or power plants must be able to react more flexibly to changes of the demand. As an alternative or in addition to the new construction of peak­load power plants (pump storage systems, gas power plants), load-flexible dust burner technologies can be used in existing incinerators to increase the load flexibility and the fuel flexibility when using especially local regenerative fuel sources. Flexibility of the burner concept means an increase in changing fuel composition and non-stationary operation, which may cause changes of the combustion behavior and, hence, of the emission behavior. Flexibility in fuel sources changes the combustion and emission behavior, too, especially with regard to low rank fuels with high ash contents containing chlorine and alkali species. To control these non-stationary processes in the burner and downstream boiler area for an efficient operation, contact-free optical measurement methods are applied in addition to the measurement systems existing in the furnace chamber and furthermore control methods based on computational intelligence. Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 1334-1337

This contribution presents a user-friendly data reduction routine for Pitot probes based on widely available software with a fluid properties interface. The data reduction process rests on the general balance equations and the fluid database and calculation program REFPROP by NIST. In the corresponding calculation sheet, the user can easily select the fluid and manually or automatically insert the probe data and stagnation conditions of the measurement. A robust algorithm directly calculates the freestream Mach number and other flow and thermodynamic quantities. The new Pitot probe data reduction routine's accuracy is assessed through several test cases, including the subsonic and supersonic flow of dry air, Novec 649, and siloxane MM in the dilute and dense gas regime. For compressible non-ideal gas flows, it is found the classical Rayleigh-Pitot equation is systematically in error even in the dilute gas regime where relative deviations of more than 10 % were noticed. In the dense gas regime, the Rayleigh-Pitot equation fails dramatically in calculating the freestream Mach number, and errors larger than 60 % were observed.

The paper presents the Danish case of development of wave energy devices and outlines the established best practice. A brief overview of international standardization efforts is given and the Danish involvement in this described.The developed Danish best practice, which is being carried over to the work on the international standardization efforts, involves a development divided in four phases (up to demonstration level). The methodology followed in the individual phases (with focus on the first two) is described. The main idea is that each of the phases should provide valuable information for the developers and investors, before the project is taken to the next phase. The paper presents the Danish case of development of wave energy devices and outlines the established best practice. A brief overview of international standardization efforts is given and the Danish involvement in this described.The developed Danish best practice, which is being carried over to the work on the international standardization efforts, involves a development divided in four phases (up to demonstration level). The methodology followed in the individual phases (with focus on the first two) is described. The main idea is that each of the phases should provide valuable information for the developers and investors, before the project is taken to the next phase.

A promising way to store alternating electricity from renewable sources like wind and sun is to produce pure hydrogen via electrolysis and to use this hydrogen to synthesize liquid transportation fuels and chemicals. As presented in 2015, the Winddiesel project, carried out at Güssing, Austria, is a potential strategy to use surplus wind energy to produce hydrocarbon-based fuels, chemicals, and bio-waxes via water electrolysis and Fischer-Tropsch synthesis (FTS). By using Fischer-Tropsch (FT) diesel as a blending component with fossil diesel, a massive reduction of CO2 emissions within the transport sector can be achieved. The FT laboratory-scale plant at Güssing uses slurry reactor technology to produce hydrocarbons from biomass-derived syngas. A commercial biomass gasification plant using the dual fluidized bed technology produces the biomass-based syngas. To simulate the fluctuating hydrogen production from renewable energy sources, the load of the FT plant is varied from 70 to 150% of the standard base-load conditions. To gain comprehensive data concerning the plant performance under load-change conditions, experiments lasting 500 hours are performed with two different catalyst charges. First, a 500-hour experiment with base-load settings is carried out to obtain reference data. In the second experiment, load changes are performed using an equivalent catalyst charge. It was observed that, depending on the catalyst, almost equal results for product distribution and composition could be reached for base-load and load-change settings. Furthermore, catalytic attrition to fine particles (< 5 µm) was investigated. The amount of catalyst fines ranges from well below 20 up to 60 mg/kg of dry product wax. This means that 0.5 to 2wt.% of catalyst undergoes attrition to fines in one year. Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 960-966

In this study, an optimum design in which pole arc offset has changed for a salient pole generator which able to give the best sinusoidal voltages have been made. Once electromagnetic analysis of the studied generator is being made, performance over producing better sinusoidal voltages rather than the shape without salient pole arc offset have been seen. Static magnetic and analytic designing of the dealt with salient pole generator have been made, and pole arc offset's effect to the induced voltages has been commented. If the offset raises by such analysis like changing pole arc offset of the generator at full load state, the obtained generator voltages approach to more accurate sinusoidal wave form with eliminating the harmonics.