Modelling and simulation of a molten salt loop of a solar tower power plant in a Modelica environment

Concentrated solar power systems provide a high temperature heat source by concentrating solar radiation for electricity generation. To ensure a stable output, plants with molten salt-based energy storage system have been developed. This study aims to understand the dynamic response of the molten salt loop of a 50MW power plant by modelling and simulation. Such a loop includes a receiver, a hot and a cold storage tanks and a steam generator (heat exchanger). The work was done with the Modelica programming language and Dymola under different working conditions. The simulation results showed that the receiver could reach steady state in 30 s. However, it took~5.5 hours for the storage tank to reach the steady state. The response of the heat exchanger was found to also be very quick with a steady-state reached within~1500 s to reach a completely steady state.