Molten Salt Thermal Storage Discharge Calculator

Molten Salt Energy Storage Basics

Concentrated solar power plants frequently employ molten salt storage to dispatch energy when the sun is not shining. A mixture of sodium and potassium nitrates remains liquid between roughly 290 °C and 565 °C, storing heat that can later drive steam turbines. Determining how long a tank can supply power depends on its volume, temperature differential, the heat capacity and density of the salt, and the plant’s power draw.

This calculator estimates stored thermal energy using the sensible heat equation:

_p\DeltaT

The result in kilojoules is converted to kilowatt-hours by dividing by 3600. Dividing by plant power (converted to kilowatts) gives discharge duration. A logistic risk function gauges the likelihood of failing to provide six hours of output, a common benchmark for grid reliability contracts.

Design Considerations

Parameter	Influence
Volume	Directly proportional to stored energy
Temperature Difference	Higher ΔT increases capacity but raises material stress
Specific Heat	Varies with salt composition; higher values store more energy
Density	Affects mass and thus total heat

Engineers must also consider heat losses through insulation, stratification within the tank, and pump efficiency. Although not explicitly modeled here, these factors reduce usable energy over time. By adjusting the inputs, users can explore how system design impacts discharge duration and risk of shortfall.

Molten salt storage offers a pathway to dispatchable renewable energy. Understanding discharge characteristics aids in sizing tanks, planning maintenance, and evaluating economic feasibility. This detailed explanation, incorporating MathML and a scenario table, enriches comprehension beyond the raw calculations.