One of the biggest points of confusion and apprehension for new and prospective electric vehicle owners is charging. In the US, we have electricity available almost everywhere, but unlike gasoline where most pumps look about the same and take about the same amount of time, electrical connections can vary widely in form and speed. Once you know the lingo, it’s really not so bad, so let’s break it down.

First, a couple definitions:

kWh – A unit of energy that means how much total range you’ve gotten. It varies with how many kW you’re getting and for how long you charged.

kW – A unit of power that means how much range you’re getting per hour. It varies with the electrical voltage and current available from the connector.

Mi/hr – Tesla also likes to specify charging rates in miles of range per hour or mi/hr. This sounds more intuitive than the technical term of kilowatts or kW, but it can also be confusing since it has nothing to do with speed in miles per hour or MPH. It can also be confusing because it’s different for every vehicle. For example, charging a Model 3 at 11.5kW it will show 44 mi/hr on the display, but the same 11.5 kW on a Model X will show 30 mi/hr. The smaller, more efficient Model 3 simply goes farther on the same amount of energy.

As we go through the options, also remember that these are maximum possible charge specifications and actual charging rates can vary. As your battery fills up or if it’s excessively hot or cold, the car will slow charging to protect itself, or if other vehicles are plugged into the same source it can also slow charging.

Keep in mind that these figures and chargers primarily apply to the US; many other countries use different plugs, voltages, and charging infrastructure.

LEVEL 1: 120V AC

Mobile Connector Version 3 with 120 V wall plug

This is included with your vehicle, and uses the standard 3-prong plug used for most electronics in most of the US. This option is only realistic if you’re primarily leaving your vehicle plugged in and charging every night, and only driving short distances to work and shopping, and using the Supercharger network for longer drives. This method is so slow that it’s known as “trickle charging.”

• 2 mi/hr
• Up to 16A @ 120V
• 1.9 kW

LEVEL 2: 240V AC

NEMA 14-50 plug for Mobile Charger

The Mobile Charger is included with your Tesla vehicle, but the NEMA 14-50 adapter is sold separately. This option is good for starters; for most people, we recommend leaving the mobile charger in your trunk for when you might need it and getting a Wall Connector to leave in your garage. The plug can supply 40A, but Mobile Connector is limited to 32A.

• up to 30 mi/hr
• 32A @ 240V
• 7.7 kW

Wall Connector connected to your house via NEMA 14-50

This is a very popular option for at-home charging. NEMA 14-50 is limited to 40A.

• Up to 37 mi/hr
• 40A @ 240V
• 11.5 kW

Wall Connector Gen. 2 directly wired into your home’s electrical panel

This is the fastest option for at-home charging, though the newest cars are limited to 48A.

• Up to 58 mi/hr on older dual-charger Model S
• Up to 80A @ 240 V (older dual-charger S and X at 80A, newer cars are limited to 48A or 32A)
• Up to 19.2 kW

Wall Connector Gen. 3 directly wired into your home’s electrical panel

The specs vary slightly between Gen. 2 and Gen. 3.

• Up to 44 mi/hr
• Up to 48A @ 240 V (Standard range Model 3 is limited to 32A)
• Up to 11.5 kW

Tesla Destination Charger

These are often located at places like hotels, wineries, and shopping centers are intended to be used while traveling when a vehicle can be left to charge over multiple hours while the occupants are enjoying their destination (hence the name). They are identical to Wall Connectors wired to a home’s electrical panel though the voltage can vary from up to 277V (really rare) to as low at 208V (pretty common). As part of Tesla’s destination charging network, these connectors can show on the Tesla navigation screen if you tap the icon to enable them.

• Up to 58 mi/hr
• Up to 80A @ 277 V (older dual-charger S and X at 80A, newer cars are limited to 48A or 32A)
• Up to 22 kW

J1772 adapter

Allows you to connect SAE J1772 charging cables to your Tesla vehicle. This is useful for a variety of situations when Supercharging, home charging, or destination charging are not available or are inconvenient, but there is ready access to other charging infrastructure such as EVgo, ChargePoint, or VW’s Electrify America network. Plugshare is a great resource for locating them.

Don’t forget to remove your J1772 adapter from the end of the charging cable when you’re done!

• Up to 58 mi/hr
• Up to 80A @ 208V (though 32A is most common)
• Up to 19.2 kW

LEVEL 3: DC Fast Charging

Tesla Supercharger

Superchargers bypass the onboard charger and directly charge the battery with DC power. This is the fastest possible charging method, and Tesla is constantly pushing the envelope on how fast their batteries can charge. Often, vehicles can be brought up to full charge within an hour, making them the only realistic charging option for long road trips that can’t be made on one charge alone.

• Up to 1000 mi/hr
• Up to 520A @ 480V
• Up to 250 kW (some older Superchargers are limited to 150 kW and neighborhood Superchargers are limited to 72 kW)

Combined Charging System – CCS

CCS is the Level 3 DC fast-charging standard other automakers have adopted. The CCS plugs resemble a J1772 plug with two large extra prongs that can carry up to 350 kW of power directly to the battery. Tesla announced a CCS adapter to utilize Level 3 charging at some third-party locations, however its release in North America hasn’t been announced yet. There are some expensive third-party CCS adapters on the market, but there are mixed reviews, so buyer beware.

SUMMARY

Who doesn’t love a nice spreadsheet? Here are the numbers above, presented side-by-side for easy comparison:

LEVEL 1: 120V AC	Charge Rate	Current	Power
Mobile Connector Version 3	2 mi/hr	16 A	1.9 kW
LEVEL 2: 240V AC	Charge Rate	Current	Power
Mobile Connector with NEMA 14-50	30 mi/hr	32 A	7.7 kW
Wall Connector with NEMA 14-50	37 mi/hr	40 A	11.5 kW
Wall Connector Gen. 2 wired directly to electrical panel	58 mi/hr*	80 A*	19.2 kW
Wall Connector Gen. 3 wired directly to electrical panel	44 mi/hr	48 A	11.5 kW
Tesla Destination Charger	58 mi/hr*	80 A*	19.2 kW
J1772 Adapter	58 mi/hr*	80 A*	19.2 kW
LEVEL 3: DC	Charge Rate	Current	Power
Tesla Supercharger	1000 mi/hr*	520 A*	250 kW*

VIDEO

In this video, Matthew explains and connects the different chargers and gives many of the charging numbers available above.