RE: Chinese Contract ????8 Apr 2022 12:23
HarChris
It was not intended to be an analysis! I’m still trying to sort out hard details for my peace of mind.
From Invinity’s data sheet - their VS3 -220 battery, basically a shipping container, weighs in at 24,600 kg with a capacity of 220 kWh of energy storage. A lot of that being liquid but a figure of 5.5 kg/kWh seems perfectly reasonable for something of that size i.e. 1,210 kg for the Vanadium.
Your figure of 5.5kg/mWh I interpret as milli-Watt hours, obviously that is not what you intend and it would imply a huge amount of Vanadium is required, even more than I originally suggested. Therefore, I assume you mean Mega-Watt hours. Since this would imply that this 24,600 kg behemoth battery only requires 5.5 x 220/1000 = 1.21 kg of Vanadium, this would seem to be a ludicrously small amount. So I think the figure of 5.5 kg/kWh seems the most likely. Whatever it is it would be nice to know the figure used in the VS3.
The figures involved in static grid storage are awesome. When 100 MWh storage is bandied about that would involve 454 of these shipping container sized batteries.
Hopefully someone can provide some clarity or I’ll keep digging.