Generally, peak energy-using hours in the US (regardless of where you live) are in the morning (6:00 am to 9:00 am when everybody is showering, eating, and getting ready to start the day) and in the afternoon and early evening (1:00 pm to 8:00 pm). In the summertime, the afternoon and early evening peak energy use dramatically increases due to the demand for air conditioning. Unfortunately, most utility companies do not charge you a lower rate for electricity used in off-peak hours, but some companies have begun the practice.

Realtime grid frequency output for Ireland here: http://synergy.chipeservices.com/ Frequency is roughly equivalent to demand and the wholesale price of electricity in Ireland.

I tried googling "us real time grid frequency" but couldn't find an equivalent. Try adding your region or electricity supplier to the search and you might find it.

Peak hours vary. One electric company may show a decrease in price for energy usage between the hours of 9 pm and 4 am. Others may show a decrease of charges on a monthly bill only on the week-ends. You must take into consideration that the peak hours for thw summer are different than in the winter months. Each state has different times. It is best to contact your utility company for information regarding your location.