Renewable energies have the advantage of a lower impact on the environment compared to other energy sources; however, their performance is conditioned by variations in weather and climate.

Over the next few years, an increasing dependence on energy supply from renewable sources is expected.

Thus, the Renewable Energy Plan 2005-2010 (PER) aims to increase primary energy coverage from renewable sources to 12% by 2010.

Of this increase, an important part corresponds to electricity generation with solar, thermal and photovoltaic energy, totaling 1000 MW new installed in the period 2005-2010.

To reach these goals and achieve greater penetration of solar electricity generation, especially in a context of strong growth in the penetration of other renewable sources such as wind, it is necessary to promote the integration of solar production within the current energy supply structures.

It is in this context that detailed knowledge of the available solar resource in advance, as it is an intermittent energy source, is of strategic importance.

The future success of renewable energies such as solar energy will be determined, to a large extent, by an adequate assessment of available resources and a correct forecast of their variability.

The importance of solar resource assessment and forecasting becomes clear when one considers that the International Energy Agency (IEA), within its Solar Heating and Cooling (SHC) program, has recently created a working group on solar resource knowledge and management, one of whose three main activities, under the supervision of Dr. Richard Meyer, is focused on improving techniques related to solar resource forecasting, on hourly to daily scales, and also on seasonal scales (http://re.jrc.cec.eu.int/iea-shc-task36/).

In the present project we intend to develop a methodology specifically designed for the estimation and prediction of the solar resource available in southern Spain, where a considerable amount of solar electric power is expected to be installed over the next few years.

For this purpose, it is proposed to use two methodologies, with the purpose that an adequate integration of the results provided by each one of them can offer better results than separately. In particular, it is intended to integrate the information obtained by:

1. The use of meteorological models for numerical forecasting (subproject 1: UJAEN)
2. The use of statistical techniques (subproject 2: UALM) The objectives of the project are to obtain:
   1. An evaluation of the potential of mesoscale meteorological models, in particular the MM5 model, for the assessment of solar resources with a resolution of a few kilometers.
   2. An evaluation of the use of artificial intelligence-based techniques, such as neural networks, for, through their application to satellite imagery and radiometric field data, obtaining estimates and predictions of surface solar radiation.
   3. An evaluation of the use of artificial intelligence-based techniques, such as neural networks, for, through their application to satellite imagery and radiometric field data, obtaining estimates and predictions of surface solar radiation.
   4. A prediction with the MM5 model and artificial intelligence techniques of the value of the radiation and temperature components over the next 48 hours in a deterministic way and with hourly resolution. And the subsequent evaluation of its usefulness.
   5. A probabilistic prediction with the MM5 model of global radiation and temperature with daily resolution at a medium term, from 3 to 10 days. And the subsequent evaluation of its usefulness.
   7. A probabilistic prediction with the MM5 model of global radiation and temperature at monthly and seasonal scales. And the subsequent evaluation of its usefulness.
   
   
   The results will be contrasted at the various sites where the research groups involved in the project have radiometric stations, and with data from the University of Granada, CIEMAT and INM.
   
   Also, the participation of the EPOs will be fundamental in order to evaluate the usefulness of the predictions. To make the results more useful, in the last year of the project, a deterministic operational prediction, as described in the third point, will be carried out for the southern half of Spain using NCEP operational analyses.
   
   The results will be disseminated through a web page. The final objective is to contribute to the future integration of solar installations, both photovoltaic and solar thermal, in the electricity production system and thus contribute to the dissemination, maturation and success of this type of energy sources.