Disclaimer: Use an certified electrician for all work that requires it by law. Electricity is dangerous and is not forgiving. Do not do what you are not qualified for and do not understand. This is only an overview of how to setup your electric setup. Be safe and be smart.
Although you probably won’t need the 2596 MW power of the Daniel-Johnson Dam in Quebec (pictured above), you will still be consuming sizable amounts of electricity. This is a short guide on how to plan your electric setup.
Most homes have 120v for standard plugs, and that is fine, but having a 220v setup is more efficient. The maximum wattage you can put on a 15A 120v dedicated plug is 1440w. You get this number by taking 80% (continuous load percentage maximum) of Amps multiplied by the voltage. A 20A circuit gives you 1920w. Always stay within the electric code that applies to your region and use the proper gauge wire.
The PSU you will use must be of high quality because it will run 24/7. It is a good practice not to load your PSU at 100%. If you have a 5 card rig with 470s and you consume 700w, you can run two rigs on a 15A socket. This breaker line must not be used by anything else.