[ncmncm]

Almost all countries have "external energy dependency" today, US conspicuously among them. Why would they all, suddenly, need independence, just because they use renewables?

You miss the point about the tropics, again. Places with reliable insolation will be exporters of synthetic fuel. None will have monopoly power, because the sun shines on them all equally. Northern countries may buy as much as they can use from them, so will not need more storage than for the time until the next shipment.

The US keeps a "strategic petroleum reserve" specifically because it has been subject to embargo by a limited group of producers. There can be no such embargo of synthetics from renewables, so no value in any such "strategic reserve".

[ephbit]

> You miss the point about the tropics, again. Places with reliable insolation will be exporters of synthetic fuel. None will have monopoly power, because the sun shines on them all equally. Northern countries may buy as much as they can use from them, so will not need more storage than for the time until the next shipment.

Imagine some non tropic country were to gradually increase its renewable electricity generation capacity. Solar on more and more roofs. The country now reaches a capacity that matches its peak electrical power consumption when the sun shines at noon and the wind blows everywhere.

Now there are two possibilities.

A. They stop increasing generation capacity. When generation is _below_ peak (because evening and no wind) this country has to rely on storage or imports.

B. The country continues increasing renewable generation capacity, so when the sun shines and the wind blows, they have excess electricity. Which they can store in batteries or as hydrogen or derivatives.

Why should any country choose A over B?

And why should they not continue to increase capacity (until all reasonable surfaces are covered) in scenario B until they maybe even are independent?

I'd say the only reason not to do that would be if imported energy were cheaper.

[ncmncm]

Even in extreme B, they may still sometimes need to import power. Or, they cannot be sure they won't ever need to. If they ever do, they will anyway know well ahead of time.

Clearly B is better, but they get to A on the way there. On the way to B, they may find they import power infrequently enough that they prefer to stop building out. That is a legitimate choice for most.

Cost is all-important, in energy policy.