Understanding Plug & Charge: Simplifying The EV Charging Experience

What is Plug & Charge?

If you’re involved at all with electric vehicles or EV charging, chances are that you have heard of Plug & Charge quite a few times recently. It seems to be one of the hottest topics in the industry at the moment, alongside EV infrastructure reliability and V2G technology.

This is no coincidence: with some EV charging infrastructure companies reaching a new stage of maturity, user research has suggested that drivers want more convenience and reliability, and Plug & Charge is the ultimate charging experience for many, rivaling and surpassing the simplicity of the gas station experience. But before diving into this, let us define Plug & Charge a little better.

Plug & Charge experience vs. ISO 15118

Depending on who you ask, “Plug & Charge” could mean the specific ISO 15118 protocol defined by the International Standards Organization, which, in addition to Plug & Charge, includes other components like V2G communication, energy management and smart charging. This technology is already in use by some companies in North America like Ford and Porsche on the automotive OEM side, and Electrify America on the CPO (Charge Point Operator) side.

On the other hand, it could mean any experience that mimics the same process, in which a vehicle is authenticated upon connecting to an EVSE, and charging and billing are authorized and done automatically, without the driver having to use an app, website or an RFID card. This category includes the Tesla Supercharger charging experience with Tesla cars, or what EVgo and GM are doing with Autocharge.

This plug-and-charge experience recreates the simplicity of the home charging experience, and it is understandable that many actors see it as a natural step forward for the EV charging experience. It might be argued that despite its advantages, other activation methods, especially apps, will still have their use in the user experience, but that is a topic for another day. Both Plug & Charge and Plug & Charge-like experiences are bound to have a role to play in the coming years, but this article focuses on the former, as defined by ISO 15118.

Benefits of Plug & Charge

As mentioned above, the technology comes with one main benefit for drivers: convenience. Naturally, reducing the steps required to start a charge makes for a more simple experience, as well as a more standardized one across charging networks and EV models. This is key in accelerating the EV transition, as the current fragmentation of the ecosystem is often cited as a reason for drivers’ hesitancy to switch to EVs.

Naturally, reducing the steps required to start a charge makes for a more simple experience, as well as a more standardized one across charging networks and EV models.

On top of this major advantage for drivers, the ISO 15118 version of Plug & Charge has a few benefits for the industry side as well. One of the most talked about points in its favor is the robustness of the technology for security considerations. Compared with other similar implementations, Plug & Charge uses Public Key Infrastructures (PKI) to authenticate the vehicle to the charger, making cyberattacks practically impossible. Another benefit of ISO 15118 is that it offers other perks on top of a more convenient charging experience, and those are getting more collateral attention as a result. The one you’re most likely to have heard about is Vehicle-to-Grid (V2G) communication, which will help with grid management and stabilization, but it also includes other ones like energy management and smart charging.

In spite of the aforementioned advantages, Plug & Charge has a long way to go before becoming a ubiquitous solution, and it faces some considerable challenges.

No more wrestling with faulty card readers. Just plug in and charge. Image from Freepik.

Challenges and Barriers to Adoption

Despite its popularity in the popular discourse, Plug & Charge is still a relatively limited activation method when compared to the two other main charging activation methods, RFID cards/fobs and remote starts. There are only a handful of EV models, charging station models and CPOs currently supporting it, whereas virtually every station supports app starts, whether through the network’s own app or a third party one.

This can be explained by Plug & Charge being at the intersection of a number of key EV industry segments (EV OEMs, EMSPs, CPOs, charger OEMs and roaming hubs), and therefore requires a lot more collaboration when compared with remote start (the most popular activation method). There are hardware requirements on top of the usual software ones, and many companies are still forming the necessary partnerships to try out the solution.

As mentioned earlier, ISO 15118 is a very robust standard, but this comes with the cost of it being a fairly cumbersome and complicated technology to implement. The PKI required can only be issued by a certified entity, and the certification represents a major financial investment, prohibiting many potentially interested actors to get involved directly.

Another barrier to mass adoption of Plug & Charge is that it is deeply linked to eRoaming, which itself is not yet ubiquitous. While the electric vehicle is used as the authentication method, the EMSP it uses can still only activate the charge points it has access to, and if the EMSP in question has limited eRoaming capacities, its drivers will either have to rely on another activation and payment method for non-roamable stations, or greatly restrict their available charging options. It is therefore key that companies interested in Plug & Charge also carefully consider how they approach eRoaming. A hub approach is often the most convenient and scalable solution.

If the EMSP [...] has limited eRoaming capacities, its drivers will [...] have to rely on another activation and payment method for non-roamable stations.

Future Prospects of Plug & Charge

As Plug & Charge continues to evolve, addressing challenges related to eRoaming, interoperability, and collaboration will be paramount. The concept of Plug & Charge will coexist with other charging methods, catering to the diverse needs of the EV market. Additionally, it will be interesting to see the role played by legislative bodies in the shaping of the trajectory of Plug & Charge technology.

In conclusion, Plug & Charge holds immense promise for revolutionizing the EV charging landscape, offering a glimpse into a future where seamless and efficient charging experiences become the norm. Embracing collaboration, standardization, and innovation will be key to unlocking the full potential of Plug & Charge and driving the electrification of transportation forward.