Tesla Opens Up Its Charging Connectors To All, But The World Probably Won’t Listen

May 21, 2023

Tesla's comparison of the size of their connector with the standard CCS charging connector

Tesla today declared it was opening up the Tesla charging connector for use by anybody, and renaming it the "North American Charging Standard" (NACS.) They invite all makers of charging stations and cars to use their connector, instead of the J1772, CCS and CHAdeMO connectors currently used on non-Tesla cars.

Even though the Tesla connector is superior in pretty much every way to the other connectors, and even though it is the connector used on 2/3rds of all electric cars in the USA, and also used in more fast charging stations than all other connectors combined, they will have a hard fight to get this change made. Let's consider why.

The reason Tesla connectors are the most common in the USA is simply because Tesla is the giant of the EV industry. For a while, 80% of EVs sold were Teslas, though it's now down to just over 60%. Tesla was the first company to build a fast charging network — based on the same small connector — and that network is still the biggest. Other, much smaller players developed "standard" connectors, namely J1772 for slow charging and two competing fast charging connectors which battled it out until the CCS connector, which combines a J1772 with two high-current pins in a bulky double-plug, won out.

These connectors are a "standard" in that multiple industry players share them, and all could use them equally. The Tesla connector was proprietary. Tesla declared it would let anybody use its patents and make them freely, but the offer wasn't as free of strings as they claimed, so only one (not yet shipping) carmaker took them up on it. Now, it appears that Tesla has declared there will be no strings, though Tesla does not maintain a press office to confirm that.

It's an interesting question about what it means to have a "standard" which is used by only a minority of users, and which is also inferior. We’ve seen similar battles with Apple, but Apple has kept a tight hold on their proprietary connectors, so there has never been a question of the market using them even if they are superior.

Charging plug connector types for electric cars. Type 2/CCS 2/GB/T are used outside North America ... [+] only.

J1772 is the non-Tesla plug for slow charging using AC up to around 22kW, but more commonly at 1.4kW to 7kW in households. This is more closely a standard, in that almost all public slow charging stations do use this. Tesla had a big program which installed Tesla connector slow chargers at many hotels and similar locations, but since then other stations go the other way. One reason is obvious — all Teslas come with a small adapter that lets them use J1772 stations in their Tesla cars. This adapter is simple and costs only $50. As such, a J1772 station can charge all cars, including Teslas, while a Tesla station only charges the 2/3rds of cars that are Teslas. If you are putting in a station, you don't want to support just one car, even the most popular one, so J1772 is the easy choice. A more expensive adapter that lets a non-Tesla J1772 car charge at a Tesla station is available in the aftermarket, but it's not very common.

Because this adapter is simple and cheap, it's not expensive to adapt the J1772 stations to support Tesla, or for cars to carry an adapter during a transition. For most EV drivers, use of public charging stations is actually fairly rare, except at office parking lots. Even so, this need for adapters is one flaw in Tesla's proposal, but not a huge one.

The interesting game, and big difference, comes from fast charging. The hard truth is that Tesla did it better, even though they did it first. (It is in fact baffling how the "standards," deployed after Tesla showed how to do it, did it so badly.) Tesla used the same small connector as they use for slow charging, because they designed that connector to have high capacity pins for the main charging current. J1772 did not and needed extra pins. CHAdeMO (the failed Japanese fast charging plug) just used a completely different, and even larger, connector!)

Tesla also put communications into the connector from the start to do billing and authentication. As such, a Tesla charging session consists of plugging in and walking away. Such an ability was put into CCS recently, but it's overly complex and only implemented on a few cars and stations. For most users, a CCS session involves using an app or credit card and other complex UI, and problems with billing that cause failure to charge even on otherwise working stations are frequent and a source of major frustration.

Tesla stations don't even have any other way to pay. This actually is a barrier for this change. Even if new cars come with Tesla connectors, they will only be able to charge if the customer, or their carmaker, has a billing relationship with Tesla and it's set up in the car. Tesla could put alternate payment methods in, but if people want a UI at the station, that would require a major station retrofit to install screens, keyboards and credit card readers. While the "plug and play" interface is preferred by all, competing carmakers would not want to need a billing relationship with their biggest competitor to be necessary to get a good experience. Tesla doesn't say this but to make this work they might need to spin off their charging network into an independent company.

That's not an easy thing to do because today, selling charging is not a business. Tesla built their network so that customers could know they could take road trips in their cars, something that wasn't possible with EVs before Tesla built that network. The network is there to sell cars, not electricity, and a transition will take time.

Switching the non-Tesla networks to offer the Tesla connector won't be hard, and in fact will probably happen with no standardization. Teslas are 2/3rds of the EVs. If you have any hope of running a charging station as a business (good luck!) you want to be able to charge Teslas, and do it easily. You want that even if Teslas drop in market share to no longer dominate. Of course, one way to do that is that Tesla now sells a CCS adapter that lets most Teslas use other stations for $250. An aftermarket version is available for just $128. It's a bit bulky but does the job, and so stations may just expect people to have this, or even have some available to borrow at their stations.

It gets more complex for the CCS cars being made today to charge at Tesla stations. They just don't need a way to pay (the Tesla app could work) they would also need an adapter from Tesla stall to CCS car, which does not yet exist but could. The problem is all current Tesla charging stalls have very short cords which can barely reach the corner of a car — the Tesla charge port is always on the back left corner, but most CCS cars do not have it in that location. Adapters would need long extension cords, and that's no simple thing when doing 200kW — Tesla's latest cords are liquid cooled to avoid being super fat and heavy, as well as very short.

A switch to an "NACS" had to figure out what to do with all the cars made before the switch. For the Teslas it's not a big problem, obviously. The buyers of other cars will feel cheated, because they are counting on the CCS networks expanding to serve them, and that expansion will stop. To make this work, all new NACS stations, made by Tesla or other companies, would need to support both Tesla and CCS (and even CHAdeMO) for quite some time to meet the promise made to those buyers not to leave them so far behind. Possibly those buyers would have to trundle around a very heavy and expensive Tesla charger to CCS plug extension cord, but they are not going to like that at all. The makers of those cars will not want to screw over their customers, either.

One option would be a retrofit for those cars. Because the Tesla socket is so small, it could easily replace the CCS socket on those cars, but the cable length would still be a problem at old Tesla stations. New Tesla stations would presumably have longer charging cables, as non-Tesla stations already do.

Right now only Tesla cars use this connector, though Aptera has said they will use it if and when they ship. It's unclear if this is true today, but once just 1 or 2 cars going into production with "NACS" as they now call it, there is a good claim that it is a competing standard — and in fact the most commonly found competing standard on cars to boot.

As such, the many laws providing subsidies for charging stations which require the station to support a standard charging plug should now apply to all Tesla stations, which is a big win for Tesla. They would have to be written to pick the CCS or J1772 "standard" which seems a strange thing to do when most cars use "NACS." It's also a wise choice for any new car model if it can now offer access to the Tesla Supercharging network, in addition to the CCS networks via an adapter. What car maker or car buyer would not like that?

Should Tesla pull this off, then after the transition is completed, most users would be happier. They would have a very capable plug which is sleek and light, and all newer cars would be able to charge at all stations, and older non-Tesla cars would be able to charge at more stations than they can now, but not all stations without a major effort.

The problem is, Tesla has made enemies, in some cases just by being the dominant competitor. Most non-Tesla charging stations were funded with government subsidies, and these subsidies had rules that demanded "standards." Indeed, such rules in Europe made Tesla give up their superior connector and switch to the European version of CCS. The same rules had Tesla bid to make stations which added a CCS and CHAdeMO cable. (The requirements for CHAdeMO, which is really only used by Nissan Leafs and a few minor cars, will probably fade.)

In some cases, rules requiring standard connectors in order to get subsidies may now permit the Tesla connector now that Tesla has opened it up and offered it as a standard. Aptera will use it though is not in production. So this could be a way just for Tesla to take advantage of certain rules.

Tesla does it big — this is a 72 stall charger in Shanghai. With so many stalls, waiting is rare ... [+] and short, and power sharing takes advantage of the way cars only take top power when empty. In addition, if some stalls are broken, it's no major problem for drivers.

Recent federal bills designed to put fast charging at every 50 miles on the highways seem to be written to leave out Tesla. Aside from requiring CCS, the rules also require things like credit card readers for old-world payment, rather than the superior plug and charge approaches. Rules also require that stations be able to provide 150kW to each charging stall (usually 4 of them) at the same time. Tesla's approach, again superior, is to make larger stations with 8 to 32 stalls, with each stall able to do 250kW, but with some power sharing, so they can't always do 150kW to each one. While they usually can do this (because some fraction of the cars at a big station are more than half full and no longer can handle even 100kW) they can't always and don't meet the requirement. That's sad, because as a driver, if going to a station which has 600kw provisioned, you would much, much rather have an 8 stall station sharing the 600kW than a 4-stall station where each car is assured 150kW. If you’re the 5th car at such a station, and (unlikely as it is) all the cars are empty, you can still get 125kW for each car. At the other station, you’re sitting waiting for somebody to leave. If you’re the 8th car at the 4-stall station you’re 4th in line and going to wait for hours, instead of charging at 100kW while the other cars who have been there for a while are charging at 50kW because that's all they can take by that point.

Mandating an inferior design is why we shouldn't let government regulators design how charging stations work.

For Tesla's superior system to take hold, the regulators will need to get out of that mindset too.