Figured I'd share my experience for anyone in Texas comparing electricity plans, especially if you have solar, batteries or EVs.  
I'm currently on Direct Energy's Twelve Hour Power plan. My free period is 9PM-9 AM, and my EFL states that both the energy charge and TDU delivery charges are $0 during those 12 hours.  
We're a family of 5 in a \~3,200 sq. ft. home and definitely aren't energy-conscious. Our total electricity consumption is typically around 3,000-3,900 kWh/month. Almost everything in the house is electric except the stove, and we also charge EVs.

In one recent 32-day period, we used roughly 1,570 kWh during the free 9 PM-9 AM period alone.  
I have a 14.35 kW solar system with 35 Qcell 410W panels and 2 Tesla Powerwall 3s. I shift EV charging and other large loads into the free period, then use solar + the Powerwalls to minimize what I pull from the grid during the expensive daytime period.  
I've been using this strategy for about a year and haven't had an electric bill over $33.

The big caveat is that the daytime rate is expensive, so this plan definitely isn't automatically cheaper for everyone. You have to look at your usage profile and read the EFL. But if you have solar/batteries or can move a substantial amount of consumption into the free window, the economics can be extremely good.

Free nights + solar + Powerwalls has kept my electric bill $33 or less