This deal is huge. 60 GWh of storage typically means 20 to 30 GW of power.

It looks like sodium batteries are having their breakthrough moment.

Right now, sodium isn’t really cheaper than LFP, because LFP has massive scale. Sodium needs scale to beat LFP on price, and this is what might enable that scale. So there is still a risk we get stuck in a local optimum where LFP is relatively cheap and sodium never gets the scale to beat it. But this deal significantly reduces that risk.

60GWh means.. 60 hours of 1GW, or 1 hour of 60GW (or various other combos). Where are you getting this "typical" from? Many vendors allow a maximum rate of 50% discharge (at that speed it reduces the lifetime of the batteries, so it shouldn't be frequently done).