Heard about this on the radio this morning. Very interesting idea.
http://www.theleadsouthaustralia.com.au/industries/mining-resources/silicon-energy-storage-technology-scales-up-for-commercial-production/
Interesting.
I note they don’t talk about efficiency though.
The Rev Dodgson said:
Interesting.I note they don’t talk about efficiency though.
They did on the radio. They claim quite high levels of efficiency. But I’m sorry, I can’t recall the numbers
buffy said:
“Better than expected ERD efficiency of 31% electricity and 80% CHP”
The Rev Dodgson said:
Interesting.I note they don’t talk about efficiency though.
They did on the radio. They claim quite high levels of efficiency. But I’m sorry, I can’t recall the numbers
http://1414degrees.com.au/
Michael V said:
buffy said:“Better than expected ERD efficiency of 31% electricity and 80% CHP”
The Rev Dodgson said:
Interesting.I note they don’t talk about efficiency though.
They did on the radio. They claim quite high levels of efficiency. But I’m sorry, I can’t recall the numbers
http://1414degrees.com.au/
So pretty good as a heat store, and pretty poor as an electricity store.
That makes sense.
Something else that might make sense is to do away with the solar panels, and use mirrors to heat this stuff directly. You can then get solar electricity all night as well as when the sun is shining.
The company completed its first trials in September with a small prototype test system using about 300kg of silicon to store about 150kw of energy.
Woaaa…150 kw of energy.
probably not the companies fault…stupid reporter
The Rev Dodgson said:
Something else that might make sense is to do away with the solar panels, and use mirrors to heat this stuff directly. You can then get solar electricity all night as well as when the sun is shining.
People are trialing that style of technology with molten salt.
buffy said:
The Rev Dodgson said:
Interesting.I note they don’t talk about efficiency though.
They did on the radio. They claim quite high levels of efficiency. But I’m sorry, I can’t recall the numbers
Well the graph in the news article is wrong. Flywheel fills the gap between lithium and compressed gas. Flywheel storage is not lower power and energy than lithium.
> The TESS device stores electricity as thermal energy by heating and melting containers full of silicon at a cost estimated to be up to 10 times cheaper than lithium batteries. The high latent heat capacity and melting temperature of silicon – 1414 C – make it ideal for the storage of large amounts of energy.
I’ve never heard 1414 C called an “Ideal” temperature before. It tends to be called “too bloody hot”.
I was working on latent heat energy storage systems for CSIRO. The most commonly used is, of course, the water to ice transition. The unique properties of water mean that this can store large amounts of power, and such systems tend to be used to supplement building air conditioning systems.
The second most common is using paraffins, with halogen groups added to make them fire retardant. These are effective at temperatures typically anywhere between subzero and 200 or so degrees C.
A third type that I was working on was phase changes in salts that dissolve in their own water of crystallization. These can’t store as much energy as water/ice or paraffins. Only water afaik has been used for phase change energy storage in units exceeding the maximum possible with lithium batteries.
> Dr Moriarty said a site had been chosen in South Australia for the first 10MWh system.
I’ll wish him luck. He’ll need it.
I’ll give some thought to these extreme temperatures and to latent heat issues later.
One of the things they seemed to be happy about was the ready availability of silicon and the simplicity.
sibeen said:
People are trialing that style of technology with molten salt.
Yes, for instance https://energy.gov/eere/sunshot/project-profile-heat-transfer-and-latent-heat-storage-inorganic-molten-salts-csp-plants
Let’s compare some properties of phase change materials
Water 0 degrees C, latent heat 334 kJ/kg
Paraffins with 14 to 34 carbon atoms have melting points ranging from 5 to 76 degrees C and latent heats from 228 to 269 kJ/kg
Molten lithium 180 degrees C, 432 kJ/kg
Molten aluminium, copper, iron at 660, 1085, 1538 degrees and latent heats 397, 209, 247 kJ/kg
Molten salt Sodium/Potassium/Magnesium chloride at 390 degrees and 410 kJ/kg
Compare with molten silicon 1414 degrees C, latent heat 1790 kJ/kg.
Wow, silicon has an absolutely enormous latent heat of fusion. Excellent, the higher the latent heat is the better. Apart from the extreme temperature, this is starting to look like a good idea.
That’s such an enormous latent heat of fusion that I’m going to check it against another source of information. This time in kJ/mol.
H2O 6.01
Mg 8.48
Al 10.71
Si 50.21
Silicon really does have an enormous latent head of fusion. Though not the highest latent heat of fusion. In this table, that belongs to:
Fe3O4, 1597 degrees C, 138 kJ/mol
Magnetite is much easier to get and a lot cheaper than silicon metal, too.
I’m not sure of the best way to hold materials that hot. There could be erosion issues. But perhaps not, only way to tell would be to try it out.
Alumina would be the obvious high temperature container to try first, with a melting point of 2072 degrees C.
buffy said:
One of the things they seemed to be happy about was the ready availability of silicon and the simplicity.
Silicon is, I suppose, available but it is not inexpensive.
The Rev Dodgson said:
So pretty good as a heat store, and pretty poor as an electricity store.
That makes sense.
Something else that might make sense is to do away with the solar panels, and use mirrors to heat this stuff directly. You can then get solar electricity all night as well as when the sun is shining.
Quite, quite.
This is a very annoying article. The diagram seems skewiff and wrongly labelled, and the units are used wrongly. I’ll try not to let that poison me for the technology.