Fast Charger Reliability Study

[seatosummit]

Interesting paper I stumbled upon while doing some research for work.

Highlights the disparity between what charge point operators are reporting for their uptime vs what actual users are experiencing.

18 months old at this point, but I trust a lot of the same issues highlighted are still present.

https://evadoption.com/wp-content/uploads/2022/05/Cool-the-Earth-UCB-study.pdf

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[VSG]

Here is part of the paper's summary, for context:

Overall, 72.5% of the 657 EVSEs were functional. The cable was too short to reach the EV inlet for 4.9% of the EVSEs. Causes of 22.7% of EVSEs that were non-functioning were unresponsive or unavailable screens, payment system failures, charge initiation failures, network failures, or broken connectors.

This level of functionality appears to conflict with the 95 to 98% uptime reported by the EV service providers (EVSPs) who operate the EV charging stations.

I suggest reading the whole thing before jumping to conclusions about any of the numbers.

In my experience, I have seen much less than a 22.7% failure rate because the problems I've encountered have been preventable, avoidable, or correctable. Too short a cable for instance - avoidable (use the right stall) and correctable (move your car). Blank screens are many times screen failures, not charger failures, and if you use the app you will still get a charge. Payment failures / charge initiation failures can be card reader errors or app errors - these are to some extent preventable (don't rely on card swipe - install the app, obtain the RFID card if available) or correctable (customer service representatives can remotely initiate a charge if you call them).

In general, it's not a controversial statement that the uptime is not 95-98%, but in my experience I have gotten an (eventual) 100% success rate at charger sites by taking action like moving to another (working) charger at the same site or by trying some of the alternatives above. I have never failed to charge at a site, but on two occasions over the past 15k miles I have failed to get an acceptable rate of charge at any charger on the site (something not considered in this study) so I decided to move on to another site rather than wait.

My biggest complaint is that is DOES occasionally take a bit of messing around until I eventually get the charging started. MAYBE that happens in 22.7% of the cases - I've never measured because to me the important part is that I do get a charge. But if it always worked first time at the first charger I pulled into it would be much better and greatly appreciated.