The largest power plant in Australia, Loy Yang, and a few others, are all located about 190km from Melbourne (pop 4.9 million). The power plants were built there not because they are close to a population center, but because that is where the coal mines are and because it is far enough away from the population centers for pollution to not be a problem. Similarly Gas plants get built near the ports, to minimize transport costs. Compare this with rooftop solar, which has very high uptake across all of Australia, including the regions like Melbourne in the darker southern latitudes. Or the wind farms, which are able to be built all over the place with no need to be stuck near some resource like coal. Turns out that wind is everywhere, and by spreading generation out you get more consistency of generation. You can build wind as close to population centers as the population allows, and people are literally building solar on their own roofs.
Cherry picking one specific plant does little to address the fundamental differences between geographically dependent and independent sources of energy. If you look at a map of gas or nuclear plants you'll see them located right next to population centers more often than not. Centralized energy production matching the centralized energy demand.
By comparison wind has to be built out in windy areas, which are often far away. Wind blows in many places, but it's only economical to build wind turbines where it blows particularly strong. Similarly with solar power [1]. Rooftop solar is a trivial amount of energy. Realistic projections of a mostly solar grid have us transporting huge amounts of energy thousands of miles from sunny arid places to urban centers where that energy is in demand.
> By comparison wind has to be built out in windy areas, which are often far away.
That's not what people mean when they say "decentralised power generation". They are thinking of power generated where it is used. That doesn't mean the nuclear power plant or coal at a safe 50km away you are alluding to. Only one thing can do it - solar, producing power 10 metres from where it is used. Right now solar doesn't work either because you need storage. The only storage that works for domestic solar is batteries and they are too expensive right now.
It's likely batteries will always be too expensive for bulk grid storage. But retail customers pay about 3 times the grid price. If batteries half in price solar + storage become price competitive with grid generation. We don't have decentralised generation now, but if that happens it will pop up like weeds everywhere.
As it happens, I have a house battery. And as it happens, it flooded here last week, cutting mains power. We were the only house in the street for a while with the lights on. Our 5kWh battery and 7kW solar system surprised me. Normal activities were curtailed, obviously. But even when it was pissing down rain in the middle of a downpour causing a once in 50 year flood, with the solar working at 15% capacity it was still enough to drive everything bar heating and aircon. Turns out the bulk of our electricity consumption can but turned off with only minor inconvenience.
We are paying $100/mo for electricity now. If I installed another 10kWh of battery, that would drop close to $0, and I could sell power too. Which made me look up current battery prices. To my surprise, a 10kWh battery only costs $5,000. You do the math - the age or truly decentralised generation isn't too far away.
Mind you, having nuclear as a backup would be nice. Up till now it's been far, far too expensive. No one in their right mind would fund a new conventional nuclear plant, which is why no one has been building them. This is the first proposal I've seen in a while that came in at what might be a workable price. I wish it luck, but they haven't built the first one yet, and history generally isn't kind to the producers of cost estimates for the first off the block large engineering efforts.
