Prediction of solar radiation in the receiver of a central tower thermosolar plant (PRESOL)

CIESOL responsiva

Ministerio de Economía y Competitividad.






  • Grupo de Inv. “Recursos Energético Solares y Climatología”. Universidad de Almería (TEP-165)

  • University of Huelva (Spain)



The prediction of direct solar irradiance (DNI) is a research topic of growing interest in fields such as agriculture or the production of solar power. The production of electricity from Central Receiver Solar Power Plants (CRC), for which the DNI is a critical entry, is experiencing a vertiginous growth worldwide. This technology will be one of the ones that contributes most significantly to the future puzzle of renewable energies. The biggest challenge posed by these large solar installations is their integration into the power distribution networks. To do this, the knowledge of accurate predictions of DNI levels in the receiver is crucial, influencing not only the operation of the plant, but the price market itself

Cloudiness is the main source of variability of the DNI in the field of heliostats. In the event that solar radiation is not intercepted by clouds, aerosols are the atmospheric constituent that increases variability in the DNI. The CRCs are usually in arid or semi-arid zones, with a high percentage of clear skies and higher frequency of episodes of high turbidity. The need for its prediction is thus vital. However, none of the prediction techniques, in the short or medium term, explicitly provide the DNI on the surface. On the other hand, the aerosols of the lower layers of the atmosphere can reduce up to 40% the solar power that reaches the receiver, reflected by the heliostats. Although the actual attenuation is a currently unknown field, it is highly demanded. The design codes of the CRCs (HLFCAL or SolTRACE) can not reproduce such effects.


  • Predict in the short term PREDICT THE SHORT-TERM ID that reaches the receiver of a CRC. For this, it is proposed to predict the ID that reaches the surface, and develop techniques to determine and predict the attenuation of solar radiation reflected by the heliostat field on its way to the receiver.