> If it takes about a decade to build a nuclear plant then building enough nuclear plants should take... about a decade?

Only if the world had unlimited access to appropriately skilled engineers and trades people, and the mountain of resources required to construct a nuclear power station.

Training people for something as specialised as building nuclear power stations is very time consuming in its own right.

It's not that simple. If you want to build more nuclear plants at the same time you also need more workers, more specialized factories and a proven design that has been field tested so that you don't end up with a fleet of defective plants after you have built 100 of them.

>It's not as if you build one, wait until it's completely finished

If you assign a worker to Hinkley C then he is going to work at Hinkley C until it is finished. You can't just send him to a different plant. That would delay Hinkley C.

> If you want to build more nuclear plants at the same time you also need more workers

So hire more workers. Most "nuclear plant construction work" isn't some foreign species of construction work. It's pouring concrete and laying pipe. The main part that isn't is the reactor vessel itself, but that's the part that can be made on an assembly line and shipped in.

> more specialized factories

Building a factory takes what, a year? Then it's mass production.

> a proven design

This is literally the main reason construction takes as long as it does already. If it isn't accomplishing that then throw that process away and build them all in three years with plenty of time left over to correct any issues before bringing them online.

> If you assign a worker to Hinkley C then he is going to work at Hinkley C until it is finished. You can't just send him to a different plant. That would delay Hinkley C.

Fortunately there is not only a single worker in the entire country, and arbitrarily many can be trained on a scale not measured in decades.

If it was that simple why does literally every nuclear power plant run way behind schedule and way over budget?

First, because there are regulatory problems (e.g. regulators changing the rules after the part of the plant they apply to has already been built). Second, because they're not being built at scale.

Building and tearing down nuclear power plants tends to cost vastly more money (billions!) than estimated at the time of their planning, especially with the more recent ones. They require massive subsidies.

"Especially the more recent ones" is strong evidence that the problem could be solved, e.g. by building modern plants using a regulatory environment similar to the one that created the U.S. plants that have been running safely for decades.

And how much is climate change estimated to cost?

I was aleays intrigued by constant arguments around cost.

Maybe energy is too cheap! An average pair of jeans is travels the world 3 times at various stages of manufacture and distribution. That shouldnt be happening

Billions with a "b"? We're talking about climate change here. How many trillions is it worth not to get to 2 degree? 3 degrees?

what's our supply of people and equipment capable of building safe nuclear power plants? I'm going to take a wild stab and proclaim that supply is relatively inelastic and possibly extremely so in the short term...

So i'm guessing it probably is pretty close to impossible to build too many in one go simultaneously, like other relative mega-structures or infrastructure, you are generally limited to a handful in generalized localities at any one time.

You're talking about a problem that applies to projects that take on the scale of months, because you can't train new people that fast.

You can go from the existing stock of people with degrees in things like physics and chemistry to a graduate degree in nuclear engineering in less than three years, much less doing that for construction work.