Have no fear the cheez ninjas here........I have a backround in electrical.....certificates....along with alot of experience wiring houses....basically most electricity is used on heat asppliances....for instance...microwaves, blowdryers, electrical heaters....basically anything that produces heat...light and fans take less electricity....however 400w lights produce major heat and use alot of watts....99% of al home use 120V with 15 and 20amp breakers...ohms law says volt times watts eqaulls amps......v x w=amps ...so if your breaker is 15 amps, you wont have as much leway as a 20amp...once the ampridge passes the amount of the breaker your breaker will turn offf as a safety precaution to protect the wires...from burning....for 15 amp circuits you need at lest 14 gage wire....or you can use 12(thicker than 14).....but for 20 amp breaker you need 12 gage wire....all houses use 20 or 15 gage wire normally...so ya its possible to change the breaker...however you need to make surethe wire is 12 gage....most electicians use 12 for all 15 and 20 amps.....so you might not have to rewire....
