Mark - you note at the end of your article:
"The problem is that it will be a nominal 20 per cent - the power stations will still be operating at almost the same capacity, as they would be if the renewables were not there at all, and the network would be overall less efficient."

The 20% target is a target in terms of MWh instead of MW, so it will mean (if the target is met) that this will indeed be a real 20%, not a nominal 20%.

I think you meant to say that the shadow capacity will still be there, in almost the same installed capacity - but it would only run (fully) when the wind did not blow. Fully agree that the network will be less efficient.

If the 20% was to be filled entirely by wind (or solar, for that matter, which suffers similar issues in terms of max possible capacity factors) then it will mean we have a huge amount of installed capacity of wind (MW):

Total electricity consumption = 230,000GWh in 2006-07 approx
20% of this is 46,000,000MWh
= 5,300MW of capacity running at 100% capacity factor - or
= 18,000MW of wind farms running at 30% average capacity factor
= $54b capital cost installed (at about $3M/MW)

Hence, its widely acknowledged in the industry (witness investments by Origin, AGL and TRU in alternative energy technologies) that wind won't be able to supply it all (though we did count about 10,000MW of wind capacity in planning a couple of years ago).

Undidly - in the future you propose (routine load shedding to maintain frequency), you would see all electricity consumers in an area the size of Sydney (say 5,000MW in average load) automatically and routinely turned off every time the wind drops. Prepare for the riots!

ClarkKent

"Undidly - in the future you propose (routine load shedding to maintain frequency), you would see all electricity consumers in an area the size of Sydney (say 5,000MW in average load) automatically and routinely turned off every time the wind drops. Prepare for the riots!"

Load shedding of heaters only to start then if needed air conditioners.Everything else would still work.
As is now everything goes off in one area if there is not enough to go around.

My air conditioner and water heater can shut off your electricity now.
Auto load shedding would prevent that.

I've just been reading WWF Australia's report on achieving low carbon energy by 2050
http://www.wwf.org.au/publications/cr-industrial-constraints-schedule-1-v3/
Some interesting ideas about integrating wind power without burning gas but heroic assumptions about ocean power, geothermal and carbon capture. The crazy thing is while the solutions seem far fetched the problems aren't. Our current major sources of energy will be in dire straits by 2050 but we will have a much bigger population. Basically I believe it comes down to an energy storage breakthrough or assembly line nukes.

I think Clark Kent’s summery of Energy consumption is telling – if you equate available commodities to demand – I guess it is time to open a candle stick factory ; - Barristers are not permitted to tender.
After all, it was barristers who worded the Wind generator proposal – they operate on linguistic level 1-2 points above bureaucrats, and that be the reason why hundreds of millions of tax dollars have been disposed of by building big propeller Stautions called wind generators, when if you would measure the current generated on a multi meter, the 9 volt battery that operates the multi-meter is the most consistent contributor.

If you live in Sydney , take a multi-meter and measure the current generated by the 85 million dollar “Crookwell”; wind generators , the biological system of your own anatomy generates more electricity than these do.

Clark Kent - quite right on the use of MWh but I don't believe it was necessary to go into the measure. However, I will make it clearer that I'm talking about output at the time in forthcoming articles.. anyway, we can agree there is a problem with this form of energy, and its a big one.

Like I said, the debate is still all about mega whatsits per thingies. You are missing the point and the big picture. Why can't you stop getting down and dirty in "I know more than you and I know a better website?"

Just look at the post from Protagoras, an otherwise serious ecologiacal debate is turned into a comedy by quoting a "Greenpeace Advisor" on the Swedish Governments decision to chose nuclear as a means of meeting its green house gas emissions targets. A Greenpeace Advisor for pities sake? Is Protagoras serious? are we proposing putting Iran's "HaveYourDinnerDad" in charge of the Jewish Kindergarten?

Protagoras, you missed the point entirely, which was, even the most renewable concious, biggest emission reduction nation on the planet is considering going nuclear. Now focus on reality, not Greenpeace "dreamtime". The Green lobby is selling us short and it's about time it shaped up.