Solarleistungsvorhersage zur Netzintegration von Solarstrom
German
2009 - PDF 0.12MB
Der steigende Anteil von Strom aus Photovoltaikanlagen lässt Solarleistungsvorhersagen für eine wirtschaftlich und technisch effiziente Einbindung der fluktuierenden Einspeisung immer wichtiger werden.

Weiterentwicklung von Verfahren zur Solarleistungsvorhersage - Prognose von Verbundleistungen und deren Vertrauensbereiche
German
2008 - PDF 0.46MB
Die zeitliche und räumliche Variabilität der Einstrahlung und die daraus resultierenden Fluktuationen der nutzbaren Energie stellen für die Einbindung von Solarenergie in das bestehende Energieversorgungsnetz eine besondere Herausforderung dar. Bei steigender PV-Netzdurchdringung ist zu erwarten, dass - analog zur Entwicklung auf dem Gebiet der Windenergieeinspeisung – eine verlässliche Solarleistungsprognose für das Netz- und Erzeugungsmanagement unabdingbar sein wird.

Weiterentwicklung von Verfahren zur Solarleistungsvorhersage: Prognose von Verbundleistungen und deren Vertrauensbereiche - Poster
German
2008 - PDF 3.14MB
Eine verlässliche Solarleistungsprognose wird mit steigender PV-Netzdurchdringung für das Netz- und Erzeugungsmanagement immer wichtiger. Wir stellen einen verbesserten Ansatz zur Strahlungsvorhersage vor und gehen dabei insbesondere auf die Vorhersagequalität von Verbundleistungen und die Bestimmung von Vetrauensintervallen ein.

Qualified Forecast of Ensemble Power Production by Spatially Dispersed Grid-connected PV Systems
2007 - PDF 0.34MB
The contribution of power production by Photovoltaic (PV) systems to the electricity supply is constantly increasing. An efficient use of the fluctuating solar power production will highly benefit from forecast information on the expected power production. This forecast information is necessary for the management of the electricity grids and for energy trading.

Solarleistungsvorhersage f ¨ur die Netzintegration von verteilten Photovoltaikanlagen
German
2007 - PDF 0.25MB
Die zeitliche und r¨aumliche Variabilit¨at der Einstrahlung und die daraus resultierenden Fluktuationen der nutzbaren Energie stellen f¨ur die Einbindung von Solarenergie in das bestehende Energieversorgungsnetz eine besondere Herausforderung dar. Eine Vorhersage der erwarteten Leistung erm¨oglicht eine an die schwankende Energieproduktion angepasste Steuerung von Systemen mit einem hohen Anteil an Solarenergie und kann so zu einer effizienten und wirtschaftlichen Nutzung von Solarenergie beitragen.

Validierung und Optimierung eines Solarstromprognosesystems unter Berücksichtigung von Ensemble-Effekten
German
2007 - PDF 0.58MB
Photovoltaik liefert im Sommer schon einen nennenswerten, und beständig wachsenden Beitrag zur Stromversorgung. Um diese Einspeisung möglichst effizient zur Netzregelung einsetzten zu können, ist ein Solarstromprognosesystem in Entwicklung.

Advances in Radiation Forecast Based on Regional Weather Models MM5 and WRF
PDF 0.09MB
With growing installations of solar power plants and integration into the electricity grid there is a demand for forecasting the energy production on a short-term basis for the entire electricity Management. Within IEA SHC Task 36, which ran from mid 2005 until mid 2011, METEOTEST made tests in the Alpine region with its operational numerical weather forecast models to forecast hourly global radiation of the next 72 hours or three days. With the regional weather models MM5 and WRF, setups with different horizontal resolutions were tested. Forecast data series were validated at Swiss measurement sites from the national meteorological network for each forecasted day separately. The first tests analyzed only the direct model output while at project end statistical post-processing methods were applied. In order to have comparable datasets only periods of more than 6 months are shown. As a measure for the quality of the forecast the root mean square error (RMSE) was chosen. Improvements in setups and post-processing techniques resulted in lowering the relative RMSE from 55% to 41% on hourly global radiation. With relatively low effort significant enhancements are possible.

Benchmarking of Different Approaches to Forecast Solar Irradiance
PDF 0.33MB
Power generation from photovoltaic systems is highly variable due to its dependence on meteorological conditions. An efficient use of this fluctuating energy source requires reliable forecast information for management and operation strategies. Due to the strong increase of solar power generation the prediction of solar yields becomes more and more important. As a consequence, in the last years various research organisations and companies have developed different methods to forecast irradiance as a basis for respective power forecasts. For the end-users of these forecasts it is important that standardized methodology is used when presenting results on the accuracy of a prediction model in order to get a clear idea on the advantages of a specific approach. In this paper we introduce a benchmarking procedure to asses the accuracy of irradiance forecasts and compare different approaches of forecasting. The evaluation shows a strong dependence of the forecast accuracy on the climatic conditions. For Central European stations the relative rmse ranges from 40 % to 60 %, for Spanish stations relative rmse values are in the range of 20 % to 35 %.

Benchmarking of Different Approaches to Forecast Solar Irradiance - Poster
PDF 0.34MB
Power generation from photovoltaic systems is highly variable due to its dependence on meteorological conditions. An efficient use of this fluctuating energy source requires reliable forecast information for management and operation strategies. Due to the strong increase of solar power generation the prediction of solar yields becomes more and more important. As a consequence, in the last years various research organisations and companies have developed different methods to forecast irradiance as a basis for respective power forecasts. For the end-users of these forecasts it is important that standardized methodology is used when presenting results on the accuracy of a prediction model in order to get a clear idea on the advantages of a specific approach.

Comparison of Solar Radiation Forecasts for the USA
PDF 0.06MB
Global radiation short time forecast of three different models (ECMWF, NDFD and GFS/WRF) have been compared. The comparison was made for a half year period (summer 2007) at three different climates in the USA. ECMWF shows the best results, followed by NDFD and GFS/WRF. Uncertainty varies strongly from place to place. At Desert Rock NV all models have an uncertainty of 18%. The biggest uncertainty is seen with GFS/WRF model at Boulder CO (50%). The breakeven with persistence is reached after 2-3 hours. Distributions of hourly values do differ from measured values, but are quite similar to global radiation data based on satellite data.