Ah Shadow - 'The modelling in in your link is a complete joke?' You have not read it through.

1/ Firstly the capital cost for the 85% scenario is less than $23 billion (Appendix 13) including new transmission infrastructure (Section 5.3), so the figure of $100b you pulled out the the air is only too high by 400%.

2/ The 85% scenario assumes all surplus wind is spilled, ie. it is not used, not sold (Section 4.8.1). It is however costed at the full LCOE of wind and the scenario still stands up economically.If some of the 22% surplus could be sold to opportunistic uses within the SWIS area, the cost would reduce even further from the $128/ MWh.

3/ There are 3 power engineers on our team including men who have worked for Western Power and Horizon Power in both transmission and generation.

4/ The $23b will be paid off by electricity revenue the same as the existing generators are/ were. It will not cost taxpayers anything.

PS. Capex on WA gas project - Chevron Gorgon project was nearly twice as much ($54 billion) as it would cost to convert WA's electricity to wind / PV and cut fuel costs by > 85% forever.

Roses,

Just for starters, the 85% model incl 6000MW of wind generation. Given the 25% yield of wind generation that would require 24000 MW of wind turbines at least $2m per MW installed that would be $48bn, excluding the network requirements, the gas generation backup, or the PV cells so with very little effort we hit $100bn.

Secondly the LCOEs you give base their costs on 30yr investment, the problem with that is that wind turbines useful life is 20yrs, yet Nuclear plants are >40yrs.

Roses, I am interested in your approach. From my standpoint not being
a power generation engineer I think I can see a problem.
You have included storage and its cost in your model.
How many serial days of heavy overcast and very light winds have you modelled ?

My reasoning says that generation & storage has to cater for
N X the number of overcast still days + 1 where N = the generation
capacity and storage needed for one day..
If you cannot reach 100% reliability then all those multistory
office blocks and residential units will have to be abandoned.

I have personally logged 5 heavy overcast windless days in a row.
Some articles I have read suggest that the cost of alternative
electricity rises in a steep curve as you approach 100% reliability.
It looks like an exponential curve but no one has suggested that the
cost approaches infinity dollars, yet !

Hasbeen asked: please give just one good, & real reason why we should get out of coal,

China & the US and I believe Europe are now working on deposits that
are increasingly expensive to mine. Australia is better off but overseas
demand will push our prices up.
We will have to leave oil & coal before oil & coal leave us.

Hi Bazz,

You have raised a few good points:
1/ You are correct - renewable energy (RE) generation systems do have to cover periods of 5 or 6 consecutive cloudy days with light winds in a typical year. Furthermore in some winter months there are only a few sunny windy days between such periods. This is clearly shown in the hourly wind energy and solar radiation data, which we sourced from NASA.

2/ That means it would need huge amounts of storage to get through a full year with wind and solar energy alone and we have modeled this as being prohibitively expensive (LCoE > $500 / MWh). Instead, these periods must be covered by fueled generation. In 100 % RE scenarios this is a combination of OCGT turbines fueled with bio-oil and solar thermal with molten salt storage co-fired with solid biomass.

3/ Yes the cost of RE scenarios does increase steeply from 85% to 100% RE, but it's nowhere near exponential; 100% costs about $160/MWh compared to $128 for 85% RE.

4/ With regards reliability, no cost effective electricity generation can be 100% guaranteed to never fail, but the ones we modeled would be at least as reliable as the current coal/ gas system, as the same auxiliary reserve requirement has been costed in.

Shadow,
You have still not read the report. The 6000 MW of wind and 3000 MW of solar is INSTALLED CAPACITY (expressed in megawatts (MW)) NOT GENERATION (which is energy, measured in megawatt hours (MWh)). We have costed the full capacity required, it does not need to be multiplied by 4 as you blythly claim. Capacity of wind required for any given amount of energy generated is greater than coal because the capacity factor of wind is about .38 compared for about .83 for coal and of course our modelling takes this into account. Annual generation from the 6000 MW of wind is 18.7 million MWh and from the 3000 MW of solar, 6.8 million MWh.

I have a plan to use mice on treadmills to power the world. It's feasible, I calculated it. With genetic engineering of hairless mice with photosynthetic skin allowing them to run while storing fat for night-work, photorodentic cells (PRCs) will allow us to leave fossil-fuels behind!

Seriously, tho': http://www.sciencedirect.com/science/article/pii/S2214993714000050

Roses,

Looking in more detail, I still find the report full of heroic assumptions.

1. That the average generation of wind power is 0.38 of installed capacity, as this goes against the experience of existing installations, especially if while the PV is generating, a large portion of the power has to be spilt. The average generating capacity outside the PV range would optimistically be 3MW not nearly enough to meet peak demand.

2 The total peak demand is on average 3700 MW, and this peak demand occurs between 6:30 pm and 9pm. This would require at least 3400MW of reserve capacity and with gas availability of 80% would require > 4000MW of gas installed capacity.

3. Batteries used for storage degrade over time with constant use. Lithium batteries are significantly degraded over 2 years and need constant replacement. (your mobile phone is a perfect example)

I could go on, but in all the capex costs are hugely optimistic.