COALition on coal

Originally posted by mjp2 ↑

I doubt Snowy II is the best solution. But that's your government's choice.

"Guaranteed power", as you want to describe it, has never been available from individual coal and gas fired plants. They can't deliver that.

They all have faults that take them out of service unexpectedly. They are all are out for long periods for necessary planned maintenance. Coal cannot deliver power cost effectively ramping up into peaks. And gas is expensive but needed for the peaks that coal struggles with. The coal and gas system relies on expensive, excess, otherwise redundant capacity that runs only for peaks of demand. They rely on scheduled excess capacity plant to cover for loss of generation due to faults. They rely on excess or redundant plant to cover all the maintenance shutdowns. And they need interconnection of all that redundant, peaking and excess capacity reserves plant.

In the same way that wind and solar now draw on gas and coal for back up, and also draw on other diversified wind and solar that is running when they are not, coal now calls on gas to peak and other coal and gas plant to cover their shutdowns and faults.

One of the contributing reasons renewables grids can be cheaper is because renewables and storage allows you to flatten the demand curve - by generating into your storage at low demand periods and drawing from storage at high demand periods, you avoid the need for peakers. Batteries are ALREADY replacing gas peakers in competitive bids globally.

And while you need plenty of excess and diversified renewables and storage to provide back-up, and reliability, it's cheap to build. And operates at ZERO cost. As well as not needing peakers in the same way.

I don't expect to convince you guys, but you're going to realise at some stage that you need to think again about this.

So your example of one wind farm and one large fossil fuel plant to back it up isn't realistic. You have a large geographically diversified interconnected grid. There is no one-to-one back-up arrangement. You have fifty, or a hundred and fifty wind geographically diversified farms. And you have hundreds of massively distributed small and large solar generators as well. These also have time zone diversity to the extent possible. Which is why submarine interconnection to Indonesia can look attractive. (And WA to East coast connection). So they largely back each other up due to that diversity. For the occasions where a significant part of that interconnected capacity isn't available, you have sufficient redundancy in different locations that can deliver. And you have future battery capacity and hydro to assist in overnight generation and those periods when areas of your renewables generation are producing minimal output.

Industry analysts are already showing that that sort of diversified renewables grid with storage and sufficient diversified capacity will compete economically with coal and gas grids - that require large amounts of redundancy in peakers and the necessary redundant capacity to allow for their maintenance and faults. And which fossil fuel grids have significant coal and gas operating costs to run every day. Versus virtually ZERO wind and solar operating costs

That does rely on battery storage cost coming down, but on large diversified grids these studies show that surprisingly little battery capacity is required to deliver reliability. Their use is often more to just reduce effective costs by flattening the load curve.

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Big difference between solar & wind "guaranteed power" & coal guaranteed power.