RE "... dunkelflaute is a couple days to weeks per year..."
My guess is its VERY expensive to build the needed storage so the supply reliability matches the current reliability 99.99%? ? ( in my area there has never been any unintended power outages for several years ) Which is why its never been done?
Then again maybe people will be more tolerant of the situation. I've always though smart meters could always have a "mode" to reduce everyone's max demand to a small amount ...like a few hundred watts ...too help handle extended periods of dunkelflaute
Open cycle gas turbines are the perfect low CAPEX high OPEX backup. They are what we currently use to manage the once a year winter storm.
Force them to run on decarbonized fuels like ammonia, hydrogen, synfuels or biofuels (with decarbonized inputs) when even the backup needs to be decarbonized.
