Daily Electrical Usage: Data Collection Pick a convenient time of day to take readings from your electric meter. You’ll need readings roughly a day apart, but if they differ by only an hour or two, that should be fine. Pick a consistent time you’ll remember, though, such as after getting home for the day. You need to start by doing an initial meter reading, then follow up with a reading every day for the next 7 days. You’ll do 8 readings in all. Record your readings in the tables below. In addition to the data fields described above, there is a lot of room for usage notes. Record anything that might have substantially affected the electrical usage since your previous reading. This might include the amount of time people were around and awake at home, use of specific devices such as an air conditioner, clothes dryer, TV, or lighting.