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by sudosysgen 619 days ago
10-16 hours is not enough at all. On a cloudy day, solar output will only be 15-20%. On top of that, your panels really only generate for 8 hours on a very good day - the sun is a lot dimmer in the early morning and late evening. Really, you need 2x storage for a good day, if you want to deal with two cloudy days you'd want 50-60 hours of storage.
2 comments

Could you possibly read the article you're replying to again?

Even skimming through it discusses the coverage of wind and a not 50/50 system particularly to cover winter & night time. There is also discussion of a ~2% from "other" and how much storage capacity is required.

The article even goes into using wind & solar data for the simulation and reducing further the output to be conservative.

I obviously understand it's not a 100% solar system. If it was you would need to be able to deal with at least 2 weeks of bad weather, not two days, and you would have to take into account winter (dropping to about 5 hours instead of 8).

Additionally, mixing solar and wind is not as easy as it seems, because the two are correlated. If you have a major storm that makes wind energy impossible due to wind speeds above ~100km/h, you will also have clouds making solar energy unworkable. I'm not aware of any simulations modelling a 95+% solar/wind grid for storage needs, taking into account extreme weather patterns, grid topology, and equipment damage, but if you do then please link it.

I don't see any article linked in the comment I replied to. Perhaps you're mixing up two comment chains.

It's likely enough battery capacity if you combine batteries with e-fuels for longer term storage.

Assuming batteries are used for all storage use cases is one of the classic errors of energy system analysis.