Roses, we all know that the current system is not 100% but for all
practical purposes it is so close to 100% that it does not matter for
the purpose of discussion.
Regarding your storage, the input to output ratio can be pretty
dismal but how many days storage are you working on ?
The longer the number of days the higher the internal losses.

Your figures though seem to assume current electrical consumption.
With the decline in petrol & diesel use the electricity consumption
could be close to double.

Australia's high risk to petrol & diesel could mean a massive shift
to electricity for transport.

Bazz,
The economic amount of storage is about 30,000 MWh for CST/molten slat or 50,000 MWh for pumped hydro. That is enough for 24- 48 hours of demand. Battery is more expensive than either of these technologies and in my view always will be, so the economic limit would probably be 5 - 10 hours.
We assumed efficiency of 70% for pumped hydro (it will likely be better than this) and 90% for molten salt.
We scaled the 2014 load profile up by 126% for 2030. You could well be right (I hope you are) that the load will be higher than this due to widespread adoption of EV's. Electricity demand does not affect LCoE, you simply install more wind, PV, CST and OCGT's to meet the demand.

Shadow,
Glad to see you've read some more of the report, but you're still not making sense. Something about average 3 MW generating capacity outside the PV range??. Go to: http://www.sen.asn.au/modelling_findings#Attachments and study Attachment 1 (pink tab labeled 85%....).
OCGT requirement in that scenario is 3500 MW; leave one turbine in reserve and that would be 3600 MW. Even if you did need to have 4000 MW as you erroneously suggest, so what? It would still be economic because these units are cheap to install as I explained before.
We assumed an economic life of 10 years for Li batteries and this is well proven in EV's.
Our assumptions, which you allege are 'heroic', are in fact deliberately conservative.

Luciferase
Sorry I can't share your and Barry Brooks' enthusiasm for the safety of nuclear and I've already explained the prohibitive cost. I think the people of Fukushima would be the best ones to judge nuclear safety. Problem is the Fukushima disaster scenario is now (post 9/11) possible at any location; reactors have to be built to withstand the impact of a 200 tonne A380 loaded with fuel and that's why their cost has escalated in recent years. In contrast, kamikaze attacks by aircraft are hardly a problem with wind turbines....

Roses1,

You bring a cost case against nuclear when French households (nuclear) pay around half Germany's (RE), while for industry it is two thirds. (Domestic users subsidize industrial users in Germany, hence the difference in the fractions.)

What of methane escape (Section 8 of the link I provided)? If the point is to mitigate AGW, why blow that off?

Fukushima always seems to me to be a bad example of the danger of
nuclear power. If it had been built on the west coast instead there
would have not been a tsunami.

It seems to me that distributing the generating centres to take
advantage of geographical weather differences will mean each centre
will have to be many times the size of its local needs.
It may well have to support several other centres.
All this will mean a significant upgrade to the eastern market grid.
For hydro are there available sites and would it be more useful to
use them for fresh water storage.

Bazz,

Yes there will be significant new 330 kV AC transmission needed in the renewable energy scenarios. This would cost about $2.5 billion (see section 5.3 of the study, which can be downloaded from http://www.sen.asn.au/modelling_findings). This will add about $6-7/ MWh (< 1c / kWh) to LCOE, some of which could be offset by selling the surplus renewable energy. As you say very little of that energy would be used locally; in most cases all of it would be transmitted 100 - 500 km to the load centres (mainly Perth Metro region) Transmission losses of at most 3 % have been accounted for.

Luciferase

The main reason France's energy is cheap is that the nuclear power stations are old and the capital cost has been paid off. Germany has a lot of new RE plant that is being paid off. If the nuclear capacity in France were replaced by new plant the electricity price would increase greatly. But they plan to phase it out from 75% of generation to about 55% by 2025 while they are at the same time increasing wind and solar generation http://www.scientificamerican.com/article/france-loses-enthusiasm-for-nuclear-power/

Roses,

I was in a rush and mixed up my GW and MW.

As for the back up power, even your statistics show that there frequent large deficits in power generation. As the cost of a power deficit with insufficient back up would be forced outages or network collapse, there would have to be far more back up, given the availability of standby gas gens could be as low 80%, so installed capacity needs to be in the order of 4.3 GW.

Secondly, the highly optimistic $28bn spent giving WA an unstable power supply would involve shelving existing infrastructure that would be perfectly capable of providing cheap power for several decades, and ramping up electricity prices for decades, with otherwise no economic benefit.