The USA uses 120V for outlets and lighting, but most buildings have what we call "split phase" where 240V is available between two opposing sine waves. A neutral down the middle gives you 120 from either of these phases. Large appliances run on 240V dedicated circuits, the rest are 120.

And 4600 KW is only a couple tons. You'll need more than that for a 5-ton central HVAC to cool an average house in a hot or humid area.