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Comment by reportingsjr | Hacker News Reader

Keep in mind you need to multiply those power numbers by capacity factor. Solar in California is at ~29% capacity factor (much higher than I expected honestly), while nuclear is generally around 92%.

That is, Diablo Canyon actually puts out 2,070MW of power from it's nameplate 2,250MW. While 4,779MW of PV in California will generate 1,385MW of power.

So, they really only added half of a Diablo Canyons worth of capacity last year. (Still an impressive amount of power, but not as much as it seems).

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It seems that people do not understand that capacity factor is the #1 criteria when building an electricity grid.

Electricity grids do not have the luxury of being able to shut down, they must meet the demand every day of the year, every minute of the year

Technologies with an higher capacity factor are inherently more valuable than the ones who don't and technologies with an unpredictable capacity factor are worth even less than those two.

There are lots of gas generators with super low capacity factors, but the capacity factor is not the key part of the generator, it's dispatachability, the ability to generate when asked to by the grid.

Neither nuclear nor coal are very dispatchable, as they can not respond to changes in demand in cost effective ways. Gas turbines can easily, as can batteries. While the sun is shining, solar can be dispatchable, because it's easy to shut off on demand or turn on demand. But for 60%-75% of the day, solar is not dispatchable.

In the modern grid, dispatchability is a far more useful attribute than capacity factor. Capacity factor is just an incidental.

In today's world ran by fossil fuels, there's not a need to turn off the non fossil fuel production, there's always more parts of the economy willing to get cheap electricity.

What matters then is the reliability and this is why the capacity factor and especially its variation are critical. See what happened in the EU when the russian gas turned off.

Batteries are a low scale solution at best at the moment anyways and aren't working at the scale of a grid.

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