If you store 30% for 3 hours, that's 90% of peak generation. It seems, by law, you could then finish selling that excess power for the next ~1.3 hours at your maximum rate (less storage inefficiencies).
You could figure out what time of day rates are highest, because that would imply you're releasing the most pressure on fossil fuel generators.
You could figure out what time of day rates are highest, because that would imply you're releasing the most pressure on fossil fuel generators.