To save money don't only avoid the peak rate times, avoid the heat as well. You'll pay to cool your house more if lights are running till noon. I watch temps closely all day and night, outside, inside, and all over my 2 grow rooms. 9pm to 9am is IMO the coolest time of day. For the veg room, lights are on the full 18 non-peak hours.
When outside temp dips below 85 I turn off AC, and turn on 3 window fans. Pisses me off to think I'm paying to cool hot air and right outside is air the temperature I want for free. Still though, it seems I need even more air movement. Maybe it's because I have an apartment under me, also surely due to how these boxes radiate heat for hours after the sun goes down, but I find it's hard to get the temp in my place below 83 with just the fans, even if its 70 outside like it was last night. I hate letting the AC run all night. I just bought a gable fan for my attic space. 14" 1400CFM. I put a temp probe up in my attic space last week. It hit 136F the other day. So a few inches away from where I'm paying to keep 85 degree air its 130+ degree most everyday of summer.
I'll be fixing that soon as it arrives.
EDIT:
I'm hoping to get 9-12 flowering ladies under my new light setup. Perpetual grow so prob quadrants of 3or4 under each light all on different stages. Been looking into Tropf Blumat's too.