2016 Guidance Affirmed, page-328

I don't know about this - doesn't seem right to me. Did your friend explain their reasoning in detail?

Simple Cycle Gas Turbine peaker plants (like Oakey and Neerbup) are not baseload operating plants, like the big coal burners or the big combined cycle plants (gas turbine with boiler/steam turbine). So they're usually only started and run, during periods when the market price of electricity is high. High market prices are driven by supply and demand - but the most common peaks in price are due to weather extremes - i.e. when it's hot (as Oakey's in QLD and Neerbup's in WA, it's usually hot, versus cold). So you'd see a peak in electricity demand (price) when everyone's running their A/C's - so lunchtime/early arvo. As it cools down in the evening, people turn off their ACs and the demand (price) drops, so the peaker plants often shut down.

I doubt the weather's going to noticeably cool anytime soon. Most Scientists agree that Global Warming is a reality, so temp. extremes are probably likely to continue. So this shouldn't affect the temp. supply/demand balance.

What could affect it?

People could change their habits (use less power - so don't turn on their A/C's at lunchtime - unlikely IMO). Or the Government could incentivize industry to build more baseline power plants - could happen, but this takes time (and a lot of money and favourable/consistent Gov. policy, so the power Co. knows that after they invest 100's of millions of $ in building a plant, the Gov. won't move the goalposts on them). We know theses plants likely won't be coal - that word's turning into "the devil" in western countries. Same for nuclear and Australia has no nuclear power anyway - so there would be a big learning curve, if it ever did happen. It could well be combined cycle (gas turbine/boiler/steam turbine) plants - they're efficient (~60%), we have the gas (if we don't export it all), they're cheaper to build than coal plants (and less-polluting). Personally I think this's the most likely option for baseload power.

We know that the Gov. plans to shut down the big brown coal plants (brown coal is dirtier than black coal). This's going to reduce supply. The Gov. want to fill this gap with some wind power, solar power and battery banks - may work? The wind power and solar power on their own are proven - but these are very cyclical power sources. There are graphs of peak wind times and peak solar times and you can see the gaps (google it). That's what the battery banks are intended for - smooth out the peaks and keep discharging current, until they can be recharged during the next peak. This has been used on localised areas successfully (like farms) - but rolling it out over a whole multi-state electricity grid? It may work - humans are a resourceful species. But I have no doubt that there will be surprises, that will require troubleshooting, time and money to rectify.

Any period of electricity grid unreliability will cause problems/complaints and no-one wants this. So some means of reliable, peak energy generation is required - I think it probably always will be. At the moment, the most likely source of this are small, simple cycle gas turbine power plants (like Oakey and Neerbup). As technology develops and becomes cheaper, battery banks and other methods may well fill this gap - but in 5-6 years? A handful of battery banks may well be working reliably by that timeframe - but on a scale to cover the whole electricity grid? I doubt it.

As these alternate sources of peak generation build in scale, the most inefficient peaker plants will be shutdown. I'm sure Oakey and Neerbup are newer (and more efficient) than many of the current peaker plants - so it'll take time for these to become uneconomical and hence shutdown.