In addition it was proven in Ref that

In addition, it was proven in Ref. [16] that a radiation intensity of 25 kW/m2 implies that the HTF can heat up to 400 °C with a good performance if the adequate selective coating is used. Therefore, the calpain inhibitor 1 impinging onto the whole receiver at any instant will only be taken into account in the efficiency if the radiation intensity is above 25 kW/m2 at the central part of the receiver. This would imply all radiation included in Fig. 10, which is a simulation during a summer day, but not around winter after simulations shown in Ref. [17