[cyberax]

> As we pointed out, PV is still trouncing nuclear in China. So if the difference is smaller there, it's still in favor of solar.

Sure. Solar is easy to scale when you don't care about reliability, nobody is arguing with that. But it's another issue entirely when you need a stable grid.

I'm not aware of any countries (even tropical ones) that managed anything close to 100% renewables with solar. E.g. Hawaii has to pay for extremely expensive diesel generation even though they have plenty of solar potential.

[pfdietz]

And nuclear is scalable if you force other sources off the grid in favor of nuclear (and force customers to not use renewables "behind the meter").

In a fair grid, solar and wind get built out, and the residual demand has no baseload component. Unless nuclear is given the right to force other sources off the grid it becomes inappropriate.

In Texas now there is no chance of new nuclear construction. ERCOT is a competitive market and new nuclear simply doesn't make sense.

[cyberax]

> And nuclear is scalable if you force other sources off the grid in favor of nuclear (and force customers to not use renewables "behind the meter").

Not really? Nuclear is not any different from coal. And plenty of countries have coal generation in the mix. France also is majority-nuclear.

And so far, nuclear is the second known technology (after hydro) that actually demonstrated close to 100% fossil-free grid.

So far, there is nothing similar for solar. Even though it's supposed to be oh-so-cheap.

> In Texas now there is no chance of new nuclear construction. ERCOT is a competitive market and new nuclear simply doesn't make sense.

Well, yeah. Because they can just allow the grid to die during the next Arctic air blast.

[pfdietz]

Nuclear is quite different from coal.

First, coal has a much larger share of its cost as variable cost which is avoided if you don't run the plant. 40% for coal, only 10% for nuclear. This makes integrated a coal fired plant into a renewable grid easier than a nuclear plant. China is increasingly doing this with its coal plants.

Second, coal is much more forgiving of maintenance sloppiness, and even in the event of catastrophic malfunction the plant remains repairable.

Nuclear has been available in its current (and no longer competitive) state longer than solar/wind have been in their current economic state, so if you look at historical data you might conclude nuclear is better. But that's backward looking and says little about what's better in the future.

You are aware that a nuclear plant tripping offline was part of the cause of ERCOT's last winter cold problem?

[cyberax]

The nuclear power plant wear-and-tear is roughly proportional to the number of hours it runs at full power. By not running the plant, you can extend its service life (probably to more than 100 years, with periodic annealing). The main limiting factor is the reactor vessel, its steel walls can only tolerate so much neutron bombardment before becoming too brittle for service.

Nuclear power plants have similar behavior to coal plants in another regard, they take approximately the same time to ramp up/down.

> You are aware that a nuclear plant tripping offline was part of the cause of ERCOT's last winter cold problem?

They just need to build more of them. Problem solved.

Anyway, nuclear power plants went from 0% to 70% generation in France within 20 years in 70-s. We don't see anything like this happening with solar, even in smaller island countries. Solar is successful only when it's backed by fossil fuels and government subsidies to keep that fossil fuel generation running.

[pfdietz]

Sure, you can save some maintenance cost by operating at low capacity factor. But this is a minor part of the cost of nuclear energy, so you don't save much. Nuclear simply isn't constituted to be useful as a dispatchable source.

The technical ability to ramp up/down is beside the point; it's the financial ability to do so that matters.

What nuclear did in France half a century ago is irrelevant. What matters is if nuclear makes sense today. It doesn't, even if it could be done.

[cyberax]

Nuclear can be made flexible, that's my point. It works best as a constant baseload, but it's mostly because the current plants were not designed for dispatchable use (except for some plants in France).

Nuclear plants do not degrade at a constant rate, regardless of their power. By idling the plant, you extend its service life, essentially amortizing the capital cost over a longer period of time. And the capital cost is the main driver in the cost of the nuclear power, as you're pointing out yourself.

[pfdietz]

Oh, and even in the US, a coal power plant might cost $1400/kW; nuclear is at least a factor of 5 higher.