The power of Tesla chargers are 7KW, 11KW and 16KW, which correspond to different models and different access power sources as follows,

1. If you install a 220VEV Charger then the charging power supported by all models is 32A/7KW.

2. If you install 380VEV Charger then the maximum supported charging power for Model 3 and Model Y is 16A/11KW, and for Model X and Model S is 24A/16KW.

As for how many KW the power of Tesla's Supercharger is, it mainly depends on the type of Supercharger. The first generation of Tesla Superchargers is 90KW, for the second generation is 147KW, and for the third generation is 250KW.

EV Charger charging efficiency varies by power. For example, a 60kWh Tesla Model Y will take at least about 9 hours to fully charge using a 220V/7KW charger. If a 380V/11KW charger is used, it will only take about 6 hours to be fully charged.

Using the Tesla Supercharger will greatly improve charging efficiency. With the 147KW second generation Supercharger, a 60kWh Tesla Model Y can be fully charged in less than 50 minutes at the earliest.

So if you want to buy an EV Charger, you should choose it according to your model and the power level supported by your house.The high power charger requires access to 380V three-phase power, while the low power charger only requires ordinary 220V household power.