I get 6kWs from my 3 pin plug, 4 hour window for ev charging rate so 24 kWh about 150 kms per night. That is usually adequate.Presumably 8 hours given the max a 3 pin can do is around 1800 w and 1 kw equates to about 7kms.
People tell me that they can only get 3 kWs from a plug. My plug is on an external wall and has its own circuit I.e. it is directly connected to the fuseboard so perhaps a little unusual.
I am not sure where you get 1800 W from, many domestic appliances draw more than that.