The smart meter installation roll-out everywhere in recent years now affords the utility the ability to measure usage of each customer for the designated five hour period. In future customers are promised that ability also, in order to monitor their own usage hour by hour, through an online dashboard for their accounts.
Presently penalty electric rates are imposed in the summers for all use above 600 kWh without regard to time of day. Once you hit the threshold, you pay at a higher rate for the electricity. In my case that usually happens by day 20 of the month. This new way eliminates the 600 kWh threshold. Use energy during the five hour window on day one and you pay the penalty rate, period.
Some will be able to game this because they aren't home during the day anyway. For the rest of us, however, it will be a different story, shifting energy use to the mornings before 2pm and the evenings after 7pm, or to weekends, and perhaps turning off the A/C and shifting activities to the basement to beat the heat.