It’s on one of the slides in his presentation. In fact, I think it’s been in multiple presentations. May not be the easiest thing to find because I remember it being skipped over and in small print somewhere but he does speak to it.

It's likely being guaranteed because he knows the cost of installing solar and battery banks and he (and his customers) doesn't have to buy directly from local power companies.

You may be thinking of residential rates which are many times higher

I just checked in the commercial rates are slightly over 7 cents today