question about ballasts about power consumption

so i have 4 1000w light's plugged in one timer. say i unplug two lights but leave power too the all 4 ballast am i running 4000w or 2000w?

is the ballast's running with out being plugged in to the light costing money?
thanks in advance

No you will use 2000w, if the bulb is out the circuit isn't complete.