System modeling of thermal energy storage
System simulation is a key tool in the development and integration of thermal energy storage systems. It provides crucial information on technical feasibility as early as the design phase:
How do individual components behave in dynamic operation? How do they react to load changes? What interactions occur in the overall system?
In the subsequent iterative optimization phase, the model is used to determine the optimum storage size, efficiency levels and operating strategies. This makes the simulation the basis for subsequent profitability assessments - and thus the prerequisite for well-founded investment decisions.
Example: Integration of a molten salt storage facility into a conventional power plant
In a specific project, the EBSILON®Professional simulation environment was used to investigate the integration of a molten salt storage facility into a model of a conventional coal-fired power plant. The aim was to flexibly link the storage operation to electricity price signals - with storage at low grid load and feed-back at high demand.
Characteristics of the storage system:
- Capacity: 0-834 MW_el
- Storage medium: Solar salt (60 % NaNO₃ / 40 % KNO₃)
- Temperature range: 290 °C - 560 °C
- Operating strategy: Load-flexible use, market-led charging/discharging phases
Simulation results:
- Efficiency of storage operation: 43.4 %
- Optimum storage tank size: Discharge time of 0.5-4 hours
- Savings per charging cycle: Up to €10,000
- Detailed results: Mass flows, pressure losses, heat flows and much more.
- Material requirement: 9.4 tons of solar salt per MWh of storage capacity
This model-based approach allows a precise system design under realistic conditions - and at the same time provides a reliable basis for decision-making for operators, investors and project developers.
More about the study in the PDF download
