Ann: Quarterly Shareholder Update, page-36

If the heated material has gone through a phase change...is it in its latent heat stage or sensible heat stage?

Disclaimer 1: I’m not a thermodynamics physicist, just a tradie who works with sensible and latent heat in his job.

Disclaimer2: apologies if this explanation is a bit “Captain Obvious” and you already know this, just trying to answer your question.

1414 Degrees shows a good explanation/diagram of latent heat storage in their prospectus (page 33). According to this diagram a tonne of silicon will absorb 464 KW/h of heat energy from 0C up to its melting point of 1414C (or is it 1413?). This is sensible heat and pretty much works on linear scale i.e. 0.33KW/h per degree C rise.

But 1414 degrees C is where the magic happens. The amount of heat it will absorb/store to “change phase” from solid to liquid is 500KW/h per tonne of silicon. Once it’s melted and gets hotter than 1414C it will continue to store more heat but only at the sensible heat rate.

So, say they heat the silicon to 1420C. and they run it down to say 1400C they deliver the 500 KW/h of latent heat.

But if they only get it to 1350C, as they are at the moment at Glenelg and run the temp down to say 1000C they only get 115 KW/h of sensible heat .

A crude explanation and I doubt the heat exchange into the hot air for the turbine would be efficient at that low temp, but maybe someone who understands high temp heat exchangers and the Brayton cycle could add more.

Fine tuning the melting point of the silicon (I assume they mix it with something else) to below 1350C will then allow it to work as designed.


But as for heating hot water to warm the digesters it would have to be working well.