by Guest » Sun Dec 02, 2007 8:23 pm
1 kWh is 1 kW drawn for 1 hour.
But your sampling every two hours may not be sufficient given loads in your house that switch on and off automatically -- furnace, refrigerator, freezer, sump pumps, etc. You would have to get a statistically valid sample over 24 hours.
How are you measuring "whole house" power? Electric meters read energy (kWh). You could read at two different days/times, look at difference in readings and divide by the elapsed time. If you are using one of those "kill-a-watt" things, there are probably loads you are failing to measure.