New methodology based on simplifications of the short-term models of CSP for long-term tuning: a case study in Spain

Abstract

Incorporating Thermal Energy Storage (TES) to a general Concentrating Solar Power plant (CSP), gives the chance of dispatching the supplied energy to the grid and optimizing its sales. Running these plants beyond sunset supposes a complex set of decisions to be made by the plant operator at each moment, which must be previously incorporated into the corresponding plant model. In this sense, it is interesting that these models are relatively easy and reliable, reproducing acceptably the instantaneous behaviour of the plant, maintaining also cumulate results for a long time. In this work, several simplifications have been applied to a general model of a CSP with a parabolic-through collector solar field. For this purpose, certain effective factors have been included into the model, assuming incomplete information about the plant behaviour. A case study to a three-plant set in the Southern region of Spain has been carried out, being tuned to provide accurate results to the real operation of the plant, in both short-term and long-term behaviour during several years. As a result, cumulative yearly energy provided to grid agrees with those values published by Government (overall supplied energy to grid from 400 to 500 GWh/year, with a cumulative error below 1%, and less than 3% deviation among plants), since qualitatively accuracy has been observed for short-term profiles of several energy flows. It will allow to evaluate future dispatch improvements associated with this kind of plants with a lower computational charge.

Keywords

• Concentrating solar power
• Thermal energy storage
• Solar collector
• Modeling processes
• Numerical validation