I would think that the times of peak demand (and price) would also correspond with when you would be using the most of your own production and putting very little back on the line.


You're also assuming that your retail rate is cheaper than their wholesale rate.   Which it may be at times for brief periods of time but it can't be that way very often for very long or the utility company wouldn't be solvent for very long.

It would be interesting to know how much power actually gets bought and sold at or near "peak" rates.   I'm guessing that it is a very very very small %.