DNICast - Direct Normal Irradiance Nowcasting methods for optimized operation of concentrating solar technologies

The objective of the project is to provide operators of power plants using concentrating solar technologies (CST) with reliable forecasts of the direct normal irradiance (DNI).

CST have proven to be very efficient sources of “clean” power for the electrical grid. The efficient operation of concentrating solar technologies requires reliable forecasts of the DNI for two main reasons.

  • First, such forecasts yield a better management of the thermodynamic cycle because it becomes possible to dynamically fine tune some of its parameters such as the flow rate of the working fluid or the defocusing mirrors.
  • Second, the electricity production can be optimally connected to the grid.

Currently, forecasts are made by several techniques, which have their own merits and drawbacks. The uncertainty in the forecast of the DNI is still too large and must be reduced. Therefore, this project propose a concept of portfolio of innovative or improved methods and possibly hardware that can be assembled by company experts to answer the specific needs of a given plant.

To fulfil the objective, the Consortium will follow a strategy based on interactions with potential users, i.e., the plant operators. Requirements expressed by users will be collected and then converted into requirements on optical properties of the clear atmosphere and clouds for the design or improvements of methods. Users’ feedback on the advances will be later collected in the course of the project where intermediate results will be shown. A final workshop will be held for the demonstration of the final version of the methods and their combinations.

Role of SMHI

SMHI will work on improving DNI forecasts using numerical weather prediction (NWP) models. The challenge is to make progress for the shorter time range in order to make DNI nowcasts based on NWP for the 240 minute time horizon.  SMHI intends to use rapid model updates (every hour) and assimilation of high resolution (5 - 15 min in time and 1 - 3 km in space and a time window of about 1 hour) satellite imagery for general sky conditions.

Funding and project partner

This project will be carried out during 2013-2017 and received funding from the European Union's Seventh Programme for research, technological development and demonstration under grant agreement No 608623.

Project partners

Observatoire Méditerranéen de l'Energie, Fundacion Cener-Ciemat, University of Patras, Genossenschaft Meteotest, Association pour la Recherche et le Développement des Méthodes et Processus Industriels, Rheinisches Institut für Umwelt-Forschung an der Universität zu Köln, Sveriges Meteorologiska Och Hydrologiska Institut, Deutsches Zentrum für Luft - und Raumfahrt, Leibniz-Institut für Troposphärenforschung, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas - CIEMAT, Eidgenoessisches Departement des Innern, The Cyprus Institute Limited.