50 years of FORAN in continuous reinvention - December 2014 - No. 48 /Up-to-Date

SENSOL software: Gemasolar correlation and lessons learned

Gemasolar solar thermal plant, developed by SENER and owned by Torresol Energy.

Gemasolar solar thermal plant, developed by SENER and owned by Torresol Energy.

SENSOL is the tool that SENER uses for the design, calculation and technical-economic optimization of solar thermal projects. Created in 2003, it is in a continuous process of improvement and inclusion of new features.

SENSOL has been used for plant design in all the solar projects in which SENER has been involved to date, 25 in total, both with central tower and heliostat field and trough configuration, with 1,510 MWe installed (see table). Furthermore, SENSOL has been used as performance model or guarantee benchmark in most of them.

One of the most remarkable features of SENSOL is a performance simulation model fine-tuned with real plants in commercial operation. This is especially important in the case of Gemasolar, the only operational molten salt central tower system in the world.

The aiming strategy

In central tower plants, the heliostat field aiming strategy controls in every moment the actuation of each heliostat, guaranteeing that the reflected radiation onto receiver surface is below its limits, maximizing at the same time the absorbed energy. This is a key aspect both for plant operation and receiver integrity, as pointing all the heliostats to the centre of the receiver would exceed its limits, thus producing a permanent damage.

Heliostat field aiming strategy simulated in SENSOL has been applied in Gemasolar and checked during plant operation. This way, SENSOL can very accurately calculate the annual performance of any given molten salt central tower plant. In fact, not considering the actual field aiming strategy in the performance simulation will lead to overestimations in the range of 11% w.r.t. what can be obtained in real life, during plant operation.

Summarised table with SENER experience in CSP


Thermographic images of the Gemasolar receiver.  Thermographic images of the Gemasolar receiver.

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