Why does only a portion of a home's electricity go out and the rest stay on at regular intervals?
It shuts off then back on by itself??? Its either a faulty power supply to your home (one phase is shutting off somehow), or you have some serious wiring problems that needs looked at. another answer may be a "ripple hookup" from the power company ... these circuits are remotely controlled by the utilty company. the idea is to disconnect "non critical high current" loads via relays at times of peak demand (for example; turn off the electric baseboard heaters and use a propane furnace secondary heat source)... the cost per KWH charged by them is lower during off peak times. usually there is a second off peak meter near the "normal" meter. kind of a long shot but still possible if you are not aware of it.