<keep in mind the figure is in addition to the renewable power already installed which is making baseload power uneconomic>

That might have more to do with the way power is supplied. Are there 24hr supply contracts? Renewable supply will make the market unworkable. For starters you will need six to eight times the generating capacity to guarantee supply, meaning that over 80% of the power generated will go to waste. Renewable energy has its uses, but it is a moronic way to power the grid.

Aiden, I am well aware that my little battery would not produce 700Mw
in practise. I was just making the point about quoting battery size
without mentioning time.
The "they" is anyone who sounds off about batteries especially when
talking about their use in power systems.
Great for when clouds pass over on sunnt still days, frequency
stability etc, but not for backup.

The 6 Gw is to replace the closed station. The existing renewables
maybe under cloud on a still day so the 6Gw will need to be well away from the area.
And hopefully in a windy place.
The blackout problem cannot be blamed on coal fired stations.
They had enough backup installed anyway. So station going off line
was always taken up by the others.
It is only now with renewables on the scene that it has become a worry.
You said:Whether we have a reliable electricity supply doesn't have any bearing on the physics of global warming.
Of course it does ! We would not be playing with renewables if it
wasn't for AGW activists !

We will never be able to afford enough distributed renewables all
connected by the $1Trillion grid including WA.
As i have said previously there is a need for many wx stations to
be installed all around Australia fed into a computer that can measure
wind and solar and see if there is in fact enough wind & sun for 100% x 100% electricity.
If not install nuclear.

It is not just me Aiden;
http://tinyurl.com/3er4jdjv
The industry is also worried about it.

Bazz: "So the correct description of the battery would be 1400 Mwatt/hrs"

Not quite, the correct description would be "1400 MWh", eg: 1400 megawatts of power supplied for 1 hour, or equivalently 700 megawatts supplied for 2 hours.

The SI unit of energy is the Joule [J]. The units of power are Watts [W], which is a derived unit of Joules per second [J/s]. (Joules are themselves a derived unit of [kg.m^2/s^2]). And energy is equivalent to the integration of the power with respect to time. So when describing energy in terms of power supply over a set time the units work out as: W.s = J/s * s = J.

The units [MW/h] (or as you idiosyncratically wrote [Mwatt/hrs]) would be used to describe the rate of change of the power.
eg1: if a power station was starting up then these units could be used to state the rate of power increase, at any given instant, while it was firing up to normal operation.
eg2: you could use it to describe the overall average rate of increase over the whole time it took to start up: such as if a power station took 24 hrs to fire up to achieve 96 MW of constant power supply then its average rate of increase would be 4MW/h during the start-up.

This link exposes the lie of renewable energy in Europe. Solar and wind combined have over eight times the generating capacity of nuclear, yet the power provided to the grid is about the same.

https://www.energymonitor.ai/sectors/power/live-eu-electricity-generation-map

Australia should change the electricity supply market to support 24/7 power generators if it wants to maintain the economy via a reliable grid supplying low cost power. If a low carbon option is needed we need to go nuclear. The longer Australia pursues the renewable fantasy the more disastrous it will be.

Think-a-bit; No, I was just talking about the size of the battery.
Trying to put into something the average Joe Blow would understand.
If we need to explain, if the network needed to rely on the battery
it could run the show for two hours. That gives Joe a good idea of the
battery's size.
Of course what no one explains where will you get that level of power
to recharge the battery after the system overcomes the cause of the
failure, as the system is obviously running on empty, before it
happens again for the same reason.
We are heading for a worse situation than the UK's predicament.
We do not have any nuclear and no access to France.