ISO 15118 is an un-intuitive name for something that seems unbelievably simple: a set of protocols that allows an electric vehicle to communicate with charging infrastructure (like a charging station) so that all you need to do to charge your vehicle is plug it into a compatible port.
As simple as this sounds, the process to make it work for the wide array of vehicles and charging stations available is incredibly complex. More than that: The ease with which it allows users to hook up to the grid can go a long way toward accelerating the adoption of electric vehicles, and give us a bridge to a future where we can use our EVs to shore up the grid in times of need.
Background on the ISO 15118 Protocols
ISO 15118 — also called “Road Vehicles — Vehicle to Grid Communication Interface” — is a joint project between the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) that began in 2010. The central “Plug and Charge” section was released in 2014, but the standard continues to be updated and improved, with the main page for it on their website being the 2019 version. That said, as of 2020, no vehicles had made use of it. 2021 saw a handful of vehicles, including the Rivian, begin to implement it, but that’s just a start.
How It Works
Communications protocols and standards are one of those tech details that seem simple but are wildly difficult to implement, in large part because they must account for such a wide variety of different machines. Think of it this way: Every charging station, every grid, every vehicle type and every unique vehicle all have their own “language.” Communication protocols and standards need to be capable of understanding each unique language, associating it with that specific type of vehicle or device and that individual vehicle or device, and then translating messages from one to the other.
In the case of ISO 15118, they use a workaround. The EV owner creates a relationship with a provider that issues a “contract certificate” tied to the owner’s account and their specific vehicle. The contract certificate is stored on the vehicle. Then, when they plug into a charging station, the contract certificate is verified and connected to the driver’s identification and billing info. The station verifies that payment will be successful and automatically begins charging the vehicle. The provider of the contract certificate invoices the owner and manages all backend processes.
This sets ISO 15118 apart from other EV standards in two ways: first, it’s focused on the transaction between the vehicle and the charging station, while many of the other popular standards are focused more on other parts of the infrastructure. Second, the effect of this standard is much more apparent to drivers than others might be, as it directly affects their ability to roam about.
As noted by one of the above links, there is some controversy surrounding the issuers of these “contract certificates.” It’s worth reading, but not relevant to our current discussion.
EV Adoption and ISO 15118: Why It’s Important
As mentioned earlier, the adoption of ISO 15118 is slow. But having a standard that allows for “plug and charge” is important to the EV world. In the U.S., the transportation sector is the single biggest emitter of carbon, creating around 27% of emissions. And the U.S. is also the second-biggest carbon emitter in the world. A look at the news on any given day will show a new story of climate disaster, with Texas serving as a canary in the coal mine. We need a transition to electric vehicles to have any hope of reducing the ravages of climate change and stifling our dependence on oil. To do that, using EVs needs to be at least as easy and seamless as using traditional gas vehicles. The “plug and charge” method enabled by ISO 15118 would do exactly that, and help to smooth our transition to electric vehicles.
More than that, the communication protocols enabled by ISO 15118 would also provide a bridge to something called “bi-directional charging.” This is where you use your electric vehicle as a battery, either to power your home or the grid itself. Despite our dependence on electricity, the U.S. electric grid is anything but stable, and the weather extremes brought about by climate change will only serve to make this worse. We’ll see more blackouts and brownouts during bouts of extreme cold or heat. Or worse: We’ll suffer real damage to the grid, as happened in Texas.
On the other hand, with the ability to hook our vehicles up and use them as “batteries,” we can shore up the grid and keep the worst kind of damage at bay. For businesses, the ability to “back-charge” to the grid could result in reduced energy costs or other financial benefits along with simply keeping your local grid intact. For individuals, this can be used to power homes or other devices in times of emergency.
While the nuts and bolts of ISO 15118 are very complex and the standard hasn’t been fully implemented yet, the effects of it are intuitive and necessary for the growing adoption of electric vehicles. Connect with us today to be a part of the growing EV market.
International Organization for Standardization (ISO) – ISO 15118-1:2019 – Road Vehicles — Vehicle to Grid Communication Interface — Part 1: General Information and Use-Case Definition
SAE International – The ISO Standard for Electric-Vehicle “Plug-and-Charge” Faces Security Concerns
Environmental Protection Agency – Carbon Pollution from Transportation
World Population Review – Carbon Footprint by Country 2020