The household voltage in China is generally 220v.
1.5mm2 line current = = 10A (ampere); Current-carrying power = current 10a * 220v = 2200w.
Minimum line current of 2.5 mm2 = = 16A (ampere); Carrying power = current 16a * 220v = 3520w.
Line current of 4 mm2 = =25A (ampere); Carrying power = current 25 a * 220 v = 5500 watts
6 mm2 line current = = 32a (a); Current-carrying power = current 32 a * 220 v = 7064 w.
Ordinary sockets are 2.5 square meters, switches and lamps 1.5 square meters. Air conditioning is 4 square meters. If there are many appliances in the kitchen and bathroom, you need to use 4 square meters.
So the total area of the power line can be 6- 10 square meter.