NEMA 14-50 or a Dedicated EV Charger

You are ready for Level 2 charging at your home. Should you install a NEMA 14-50 outlet or a dedicated EV charger? Below are some considerations.

TL;DR; In most cases you should wire up for a NEMA 14-50 and install an EVSE with a J1772 plug. If you plan to only drive Teslas for a while, install a Wall Connector.

Fancy people call chargers EVSE – Electric Vehicle Supply Equipment. 220V home chargers are actually not chargers and the charger is in the car. The home charger is just a super fancy plug with a fancy name. Read up on basic terminology and math first, if you are new to this.

As you will see, the technical differences are minor, cost may be the same (after incentives) and it comes mostly down to convenience and how you want to plan for the future.

Flexibility

Either one will charge pretty much any current and future EV. A 14-50 requires a proper adapter. With an EVSE, you should get a SAE J1772 plug, which will plug into most cars, but with some (most notably Tesla) will require a small adapter. If you know you will only charge Teslas, you can buy a Tesla specific EVSE that works directly with the Tesla (e.g. Tesla’s Wall Connector), but requires adapter for everyone else.

You could install an EVSE and plug it into a 14-50 (especially if you already have a 14-50). That will give you the benefits of an EVSE, but it will limit your charging speed to the speed of a 14-50.

Maximum Power / Charging Speed

There is no material difference between the two. A 14-50 will might add 29 miles an hour, but a dedicated charger might add 33 miles. It will take hours to fully charge a car on both, and both solutions will fully charge a car overnight. The latter is holds even if you have time of use electricity and only charge from midnight to 6am or so.

You can install a more powerful EVSE that could add 58 miles an hour, but they are significantly more expensive and many cars cannot charge that fast anyway. Some electrical panel will not be able to handle more powerful EVSE, which will increase cost. And it still takes hours to fully charge.

Power is measured in kW, and the difference is minimal. A 14-50 provides 9.6kW max, and an typical EVSE provides 11kW max, e.g. the Tesla Wall Charger. A powerful EVSE may go up to 19.8kW. Fast Chargers – outside the scope of this article – can charge at up to 350kW. You can see that, 10k vs 20k is immaterial. If you need fast charging, drive to a fast charger.

Cost

Thick copper wire is maybe $1/ft. A short 30ft run – up and down walls and across a garage – is easily $100. Add $1/ft for conduit and a breaker makes another $50 for a total of $150 for the material, 4h labor at $75/h and you get $500 total for a minimal professional install.

This cost goes up as the distance increases. If you want wires inside walls, it will cost (a lot) more. If your panel needs to be upgraded, it may be in the thousands.

While a 14-50 outlet is cheap, an EVSE starts at a few hundred dollars. $500 is a reasonable price for a reasonably powerful (~10kW) and smart (Wifi) EVSE. The powerful ones that can push up to 20kW can easily cost $2000.

Incentives

The US, some states, and sometimes utilities will provide incentives for installing EVSE. Right now you can get 30% off from the US. Sometimes the EVSE needs to be hard wired (i.e. it cannot be plugged into a 14-50), or it will have to be smart, or any other local restrictions.

One incentive is cheaper electricity at night for the EV. That may require a smart EVSE. Some utilities will pay you if they can prevent you from charging at peak time, and that also requires a smart EVSE – one that the utility can control, but also one that can ensure that your car charges anyway if at 20%. Some utilities may subsidize panel upgrades, too.

Overall, after incentives, it may be cheaper to install an EVSE.

Convenience

Most EVSE comes with a cable management solution to get the cable out of the way. Also, the cable stays with the EVSE, so it’s always available. You only have to plug in one side.

If you use a 14-50, you need to use the charging cable that came with the car (or buy another one). If you leave on a road trip, you have to remember to stow the (possibly wet) cable back into the car after unplugging. 14-50 are not designed to be plugged/unplugged often. They were made for appliances that you unplug at most every year when performing maintenance. there is risk that the plug will break early because of the constant unplugging.

If it’s outdoors, you may have a cover lid that needs lifting with one hand while the other hand plugs/unplugs. Unplugging a 14-50 with one hand requires a bit of strength, too. Some people will quickly hate doing this frequently. You may not want to leave your mobile charging cable on the ground outdoors when you are not using it, requiring more regular work.

Cable failure is a real concern, not just for safety, but also for frustration. A broken cable may ruin a road trip, or prevent you from getting to work in time. Consider buying a second charging cable for home use only so you can leave the first on in the car if you install a 14-50

Smarts

An EVSE may provide smarts that the car (and 14-50) won’t provide, including support for charging at off peak hours or charging a batter early morning so it’s warm for departure. This may extend your range and comfort in winter (in addition to being cheaper, as discussed above). You may also be able to get data about your electricity usage that goes beyond what the car gives you.

Breakers and Wiring

Discuss all below recommendations with your qualified, licensed electrician to make sure they are according to local code.

In summary, install all the wiring for a NEMA 14-50, but upsize the wires to #6 whether you install a 14-50 or an EVSE. You will have to install a 50A breaker as long as the NEMA 14-50 is there.

A 14-50 will use a bit less current than an EVSE which means thinner wires, and thus less copper. But an EVSE may use one less wire, which will make up the difference. However, a large part of the installation is the cost of pulling the wire. So it’s worth thinking ahead to the future on this.

Even if your EVSE requires only 2 wires, still put in three, so you can later replace the EVSE with a 14-50, or an EVSE that requires 3 wires. Rewiring later will be expensive.

Similarly, even if you install an 14-50, consider installing thicker wires so that you can later upgrade to a more powerful charger. The 14-50 requires #8 wire, but if you install #6 instead (smaller is thicker), then you can later go to a slightly more powerful EVSE, e.g. a Tesla Wall Connector. #3 will allow you to go to 100A, and run two typical chargers in parallel, or a single most powerful one at 19.8kW. #3 is expensive and hard to handle due to thickness, and your panel may not be able to support another 100A, so the sweet spot is #6.

Note that a 14-50 can handle 50A peak, but EV charging is sustained. We can only charge at 80% of peak, which is 40A. Similarly, a 48A Tesla Wall Charger requires a 60A peak circuit, i.e. #6 wires. A powerful EVSE will sustain 80A and requires a 100A circuit.

NEMA 14-50EVSE (typical)
Max Power40Amp, 9.6kW48Amp, 11kW (up to 19.8kW)
Full Charge example(1)4.2h3.6h
Cost example(1)$500 Material + Labor$500 Material + Labor
$500 EVSE (up to $2000+)
Breaker50 Amp60 Amp (up to 100A)
Cable ManagementNeeds extra solutionInbuilt
OutdoorsRequires coverweatherproof
Failure14-50 and cable may fail
with heavy usage.
If EVSE fails, car supplied
cable still available as backup
SmartsCar onlyCharger may supply functionality
Comparison of NEMA 14-50 and EVSE
(1) Assume 40kWh, i.e. 30%-80% of an 80kWh battery.4

Last Updated on December 6, 2022.