Comment by eldaisfish | Hacker News Reader

Comment by eldaisfish | Hacker News Reader

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Your final comparison there is an excellent example of hand-waving away the problem of intermittency. This is something that advocates of renewables regularly want to dismiss because the discussion is a difficult one.

Wind and solar are cheap now because their fuel cost is zero and the cost of grid reliability is borne by us - consumers. In a better world, the cost of balancing the grid at night should be borne by a solar PV generator because it caused the problem.

Even if you match the energy output of a solar and nuclear plant, the component of time is ignored. On a grid powered by solar, where will energy come from at night? How many batteries will you construct? The scale of these batteries is again something that’s dismissed by claims of continental-scale grids but has that been achieved anywhere? All the batteries in the world combined can power à giga watt scale grid for hours. That’s right, hours.

Nuclear is a solution in the here and now. It buys us time to sort through these problems while we work towards a better future.

Nuclear has the same issue of intermittency. You have to either overprovisioning if you use nuclear or use battery storage. Nuclear is much more expensive than wind/solar so if you follow an overprovisioning strategy the best is to build wind/solar capacity, because it buys you more. Moreover, the larger and more integrated grids become (this is happening already for economic reasons in Europe) the less this is an issue.

Also why do you only mention solar and not wind? Maybe because eit would make your argument less convincing? The wind still blows at night, so you do not need battery storage to provide all the demand during the night.

Why are the same simplistic arguments being brought forward again and again. They have all been debunked.

> The wind still blows at night, so you do not need battery storage to provide all the demand during the night.

Is it enough wind to meet all the demand at night? And what happens when it stops blowing as much as expected for a long period of time[0]? You still need baseline power generation for quite some time to come until those questions that, well, keep getting hand waved away are solved.

0: https://fortune.com/2021/09/16/the-u-k-went-all-in-on-wind-p...

There are many studies which showed how much overprovisioning you need to go to 100% renewable with different size grids. None of these are outrageous, but it's also nothing we currently need to think about. We can easily scale up renewable capacity to 70% without significant overprovisioning. So we really just need to build lots more renewables at the moment.

If you don't have renewables for a while, and transmission line availability flags, you import anhydrous ammonia from the tropics. So, you need only minimal over-provisioning and local storage.

But then you presumably need to build these extra power plants that can use that fuel?

We have combined-cycle turbines already. More will be built wherever they will be needed.

A combined cycle powerplant is about 10% of the cost, per unit power output, of a nuclear power plant. So we could completely back up a renewable grid with CC plants and nuclear could still be much more expensive.

And, steam turbines cost more to keep working than CC turbines. But both are very mature, meaning costs won't change.

> The wind still blows at night, so you do not need battery storage to provide all the demand during the night.

The wind doesn't blow as strongly at night. It's much calmer.

Yes and demand is also much lower what is your point? Apart from the fact that your statement is highly dependent on location (it is much less true for sea installations for example).

> You have to either overprovisioning if you use nuclear or use battery storage.

Whereas with solar and wind, you need to do both, because you need the overprovisioned capacity to recharge the batteries.

No with a reasonably large grid you only need to overprovison no need for battery.

But this is really a question of economics, the mix of how much storage you want to include is really a question of cost and the specific grid. One should also say that pretty much every grid already has some level of overprovisioning, because otherwise you run into problems when some exceptional events hit.

In the end why would you pay for more expensive nuclear if you can get more capacity for the same price with wind/solar. So it is cheaper to build the overprovisioning with that. Moreover if the current trends for storage prices continue then things become cheaper still.

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