California Now Has More Than 150,000 Solar Roofs

[FBaggins]

5. That wasn't where the error was.

Label capacity simply isn't comparable across generation sources that are so different.

Let me use a different example. In a future world where solar/wind make up half of our electricity generation, there will be a need for quite a bit more gas peaker plant capacity... but those plants won't need to run very often. Their value to the grid is neither their label capacity nor the actual amount of electricity that they generate per year - it's in their availability on short notice (their ability to stabilize the grid). They'll literally get paid to just sit there - hoping that they don't get used very often. How much of that capacity would be "equivalent" to 100 MWs of solar? How much annual producing would be? Neither comparison is really appropriate because they aren't comparable by either metric.

In this case, you could compare the total amount of electricity that the solar panels could be expected to generate in an average year - to the annual generation expected from those coal plants. But the only reason that would be fair is because we're talking about SoCal (Where there's a pretty good change that almost all of the solar PV generation could directly offset the need for "baseload" generation). In most parts of the country, even that comparison would suffer from the relative value of power supplied when you want it vs. the value of power supplied when it happens to be available.