1. Description of Work (2011)



The service is entitled “Irradiance forecasts for electricity production”

Involved partners and contacts: the partner in charge of the development of the product and the service is DLR - Marion Schroedter-Homscheidt (marion.schroedter-homscheidt(-at-)dlr.de.

Prime-user: Flagsol GmbH

Expectations of the prime-user: Flagsol GmbH is currently developing a solar energy production forecast for concentrating solar power plants in close collaboration with DLR within the ESA IAP project CSP-FoSyS. ENDORSE aims at improving this service by using GMES core capabilities and by performing the R&D needed for that. Therefore, a service development from scratch is not in the focus of this service line. 


Incoming solar radiation is the most important meteorological factor that influences the power production of a solar energy power plant. For concentrating solar technologies the direct irradiance is requested, while non-concentrating technologies as e.g. standard photovoltaics require a global irradiance forecast. Depending on the use case different forecast horizons e.g. from the upcoming 30 to 180 minutes in a 15 minutes resolution up to the 48 hour forecast in hourly resolution are requested. So far, both global and direct radiation components were not in the focus of numerical weather predictions. Flagsol GmbH is concentrating on this question in its own developments and welcomes ENDORSE outcomes serving these efforts. 

For many years, the electricity grid was operated in a top-down fashion. Large power generation plants produced most of the power, which is then transmitted to consumption centres over long distances and using different high voltage levels. This operating mode is increasingly changing due to increasing renewable energy shares in the electricity grid. Therefore, additional information of upcoming renewable energy production is needed. Regional and national transmission network operators or regional utilities responsible for electricity grid stability and solar energy power plant operators acting as market players request solar electricity production forecasts. These rely first of all on a reliable solar irradiance forecast as input parameter.

For utilities or network operators the accumulated electricity production in a region needs to be forecast. For solar power plant operators three use cases have to be taken into account: (A) the participation on the electricity market, (B) the application for the license for the grid access, and (C) the optimization of the power plant operations with aspects on maintenance, solar field operations, and operations planning. 

Objectives of the service: Providing forecast of direct irradiance with a horizon of up to 48 h.

Area of interest:

Exploited GMES downstream services:

Innovation: Currently, solar energy production forecast is based on numerical weather prediction providing global irradiance in a 3 hour interval only. A temporal interpolation and a statistical separation into direct and diffuse irradiance provide 48 hour forecasts of direct irradiance.