> Storage is cheap.

And yet it's solar being built all over the world, not storage.

Storage is also being built.

But storage will lag in volume until intermittent sources like solar produces enough in any given region that there are significant periods of excess that aren't better to deal with by bringing other plants offline.

Right, it would be stupid to spend big on storage that cannot be charged up from renewables that exist. First you build enough renewables, to displace fossil fuel (and opex), then build storage when you cannot displace much fossil fuel, any more.

All this is easy for an operator to figure out, daily: add solar, fuel cost falls in exact proportion. When you have to turn off enough banks of panels enough of the time, you start building stuff to absorb that energy for later. But not until building more panels cuts your fuel cost less than building storage cuts your night-time fuel cost. (Wind input makes this calculation less deterministic.)

Exactly. There is some benefit to building some storage before then to reduce the need for peaker plants, and that is largely what happens today when storage gets built. E.g. Tesla's battery project in Australia a few years back for example.

Plus, if this catalysis system works, then excess electricity can power the process to convert methane into methanol as a chemical battery store.

That, combined with the ability to extract CO2 from the atmosphere and convert that into Methane would result in carbon neutral (or even negative, if any of the converted CO2 carbon breaks away from the O2 in the burning process as soot) any time power delivery.

Yes, you would be burning the methanol in an engine to turn a turbine but if the carbon for that process came from the atmosphere to begin with then who would be upset by that?

You could be using the excess power to actually sequester the carbon you extracted, and help fend off looming climate catastrophe.

But selling it let you pocket a few bucks, so the choice was obvious.

They should tax half the carbon you extract as if it were mined, unless you sequester it instead.

Burning hydrocarbons extracted from the atmosphere is carbon neutral assuming the electricity required for the conversion is solar/wind supplied.