I had a long chat to a friend the other day, who is high up in strategic planning at AEMO. She had some interesting stuff to say.
First of all, AEMO’s main challenge isn’t having enough generation capacity to meet peak demand, it’s ensuring that demand matches supply.
Building more renewable generation is laudable an necessary, but it’s actually making things harder for AEMO at this point, because the infrastructure is not keeping pace and can’t support both it and increasingly unstable dinosaur coal generators. Renewables have changeable output, and as the above article shows the old coal generators are too junky to rely on in a pinch either (and they’re only going to get worse). That means that AEMOs main headache is having control over the generation capacity that they have, rather than more raw capacity. The current situation is kinda like plonking a F1 racer’s engine on a torana chassis and expecting to steer the resulting contraption with a set of handlebars off a pushbike.
Basically it’s a huge failure of federal energy policy, which has been ‘do nothing and make the states and renewable entrepreneurs put together a patchwork of differing systems and pile on renewable generation capacity if they want to address emissions in any way whatsoever, then don’t fund any method of connecting, managing, or tying them all together.’
The long-term switchover from fossil to renewable generation is going to happen and is already happening. Climate science demands it and now as the old coal plants close up economics will ensure it happens regardless of the desires of politicians or mining corporations or poor ■■■■■■■ coal miners in the Goulburn Valley who’ve been lied to about its viability for a decade plus. This is simple reality, deal with it. The only question is how it is best managed.
The real issue with power generation in the age of renewables is ensuring that supply matches (not exceeds!) demand at any given time. Blackouts happen when demand or supply spike or abruptly drop, triggering all sorts of failures to chain-react across the grid. This is what happened in SA last year - supply dropped abruptly when the wind blew those high-tension towers over and the rest of the system - while it had sufficient raw generation capacity to meet demand - couldn’t compensate fast enough to avoid a cascading failure (especially when there was a stuff up in communication and one of the gas plants that was meant to be on standby for this sort of thing didn’t do its job) The table in your post is true enough, but nobody at AEMO cares if wind farms are only producing at 25-30% max capacity all day - but they DO care if the a coal plant breaks down and goes from 100% to 50% capacity in an instant with no warning.
With renewables, there is a lot more variation on the supply side than there is with a fossil-fuel system in good working order. (In a crumbling relic fossil fuel system like ours this is not necessarily the case, because the supply tends to shit itself at unpredictable moments). A system with higher variability needs better control infrastructure to direct power where it’s needed. That’s what we haven’t currently got.
There’s degrees of variability too. Renewables tend to vary in a moderately predictable and smooth way - sure you have times when the wind doesn’t blow and the sun doesn’t shine across the entire state, but you’re likely to have a bit of warning (you don’t even need a day, an hour is more than plenty) so you can plan ahead for it. Also, the ramping up and trailing off of renewables tend to be gradual rather than immediate. On the other hand, when a rusty 1940s coal plant bursts a boiler and goes offline, you lose a large amount of generation capacity, instantly and with no warning, which is a lot harder to compensate for, and much more likely to cause a cascading failure n the grid.
To illustrate - AEMO is ALREADY planning ahead for I think it’s 2026, when a total eclipse will occur in the southern hemisphere resulting in every solar pv panel in Australia stopping generation abruptly in the middle of the day for a short period of time. You CAN do this sort of planning with renewables because fluctuations tend to be the result of predictable physical processes - Europe handled something very similar a year or so back.
I’m sure I’m getting some stuff wrong here because I don’t remember the entire conversation, but the big takeaway - finding enough sheer amount of generation capacity is not the real problem. Managing the power that has been generated is the real challenge.