Part one of a multi-part series discussing the shortcomings of the recent NEVI final rule and what that may mean for EV charging in coming years.
EV charging has a foresight problem. Nowhere is this more apparent than in the much-anticipated National Electric Vehicle Infrastructure Formula Program (NEVI Formula) final rule released by the Federal Highway Administration (FHWA) last month.
NEVI is a big deal. We are talking about $5 billion* in dedicated federal funding that is being allocated to all 50 states, DC and Puerto Rico to build out a national EV public charging network, with stations to be established along every major corridor of the national highway system. It’s among the largest public infrastructure programs in living memory, one that is expected to be key in driving the transition to electric vehicles and putting the US on track to meet its 2030 climate change goals.
Within 90 days of Congress's passage of the legislation creating the NEVI, in February 2022, FHWA released the statutorily mandated program guidance, and last month, after a notice and comment period, FHWA issued a final rule establishing "minimum standards and requirements" for NEVI-funded projects. The problem is that the NEVI final rule will get us the charging infrastructure that we needed back in 2015, not what will get us to 2030 and beyond. While well intentioned, the final rule reflects a number of clear blindspots that will—at best–result in missed opportunities. At worst, it will leave us with expensive eyesores along our highways that will end up costing us much more than necessary to incrementally upgrade and expand to meet the inevitable demand.
This is the single biggest flaw of the NEVI final rule. We are about to undergo a transportation shift of unprecedented speed and scale as we move from gas-powered to electric vehicles. That means even “minimum” requirements for charging infrastructure must be designed to allow for and encourage cost-effective future expansion and innovation. Over the coming weeks, I’ll write up a series of posts focusing on specific language in the final rule that undercuts that critical objective, among other problems.
Before we get to all that, though, I want to start with the simplest possible illustration of NEVI’s fumbles. One of the final rule’s most obvious misses is its required charging speed specifications–or more accurately, the lack thereof. While the NEVI guidelines do specify a minimum of 150kW chargers for corridor charging locations, they fail to specify the amperage of the charging cables attached to those chargers. That matters because it leaves open the possibility that our shiny new infrastructure will charge 95% of EVs on the road today at half that speed.
In fact, it is already common to see chargers on Plugshare where the majority of reviews are complaints about only getting 75kW out of a 150kW charger, each posted by an EV driver who does not realize that the chargers are working fine and that 75kW is the maximum that the chargers can deliver to their car by design. EV drivers—and sometimes even the site hosts and municipalities that are buying chargers from the charger manufacturers—are not always aware of the nuance in how chargers are rated, and the drivers pay the price in slow charge times.
There are three factors in the charging speed equation. Power (P) equals Current (I) times Voltage (V). Cars today typically come with pack voltages between 400V and 800V, and the CCS charging standard supports up to 1000V. The vast majority of EVs on the road operate at 400V, and this lower voltage means a higher current is required to reach a given power level. To safely carry a higher current, cables need to be thicker or water cooled, adding significant expense to the charger. As a result, it is not uncommon for charger manufacturers to communicate the power rating of their chargers at 1000V, only for them to deliver less than half that rated power with 400V cars because that is all the cables can handle.
In the case of the 150kW chargers that NEVI specifies, a charging manufacturer would be totally compliant installing a 150kW charger with a 200A rated cable. This would certainly be capable of charging an 800V Porsche Taycan at 150kW, but would deliver a maximum of 80kW to almost every other EV currently on the road, whether a Tesla, Ford, Nissan, Polestar, Rivian, Mercedes, BMW, Toyota, Subaru or Volvo.
The most frustrating part is that NEVI final rule acknowledged this issue and willfully chose to ignore it. In response to a suggestion made in the open comment period to add amperage ratings to the guidelines, FHWA offers this: “Regardless of the operating voltage of the battery, so that EVs are able to receive at least 150 kW per port, FHWA suggests that DCFC connectors be rated with a current carrying capacity of greater than or equal to 375 Amps.” By making minimum amperage a suggestion instead of a requirement, FHWA not only opened us to investing in inferior hardware, but crucially missed the chance to dispel consumer confusion about how charging works.
While manufacturers will eventually be moving to 800V cars in order to take advantage of larger, faster charging batteries, virtually all EVs on the road today, and the majority of those slated to be built in the next five years, may be unable to reap the true utility of the infrastructure we’re investing in. The shame is that the NEVI final rule is also ill suited for the EV road of the future, for reasons I’ll outline in my coming posts.
*FHWA is expected to separately release guidance later this year for an additional $2.5 billion discretionary grant program targeted at delivering EV charging infrastructure to rural and underserved communities.