What you are referring to is "time-of-the-day" pricing for energy. Today, many EV owners are subscribing to this type of pricing from their utilities. Such pricing, as the name suggests follows a fixed pricing schedule that is tied to the time of the day.
Going forward however, utilities will be offering what is called as "Residential Real Time Pricing" (RRTP). This means that your energy rates will change in real time, typically in response to the wholesale energy rates. If you can intelligently adjust your electricity usage in response, you will be able to save on your electricity bill. ConnectMyEV’s advanced charge management adjust the EV charging rate in response to real time pricing, to deliver these savings to you.