Can we store heat in salt?

Is it possible to store heat in a salt?

What a strange question!

Even more strangely, the answer is: Yes.

Sodium nitrate, for example, is used to store heat in what are called concentrated solar thermal applications, in which temperatures can reach above 400 degrees C.

Why is a material like sodium nitrate used for storing heat? Because these fall under the category of “phase change materials” or PCM for short.

PCMs typically absorb or release large amounts of heat with high efficiencies when they change from one phase to another – absorb heat when they change from solid to liquid and release heat during the reverse phenomenon.

PCMs such as sodium nitrate thus are promising materials of choice for energy storage.