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How would paying for an EV charge work like this? Would you select an amount of credit in currency (presumably via buttons on the charger?) then tap-to-pay for

by g_p 3y ago

How would paying for an EV charge work like this? Would you select an amount of credit in currency (presumably via buttons on the charger?) then tap-to-pay for that amount? (I believe there are some limitations on tap-to-pay transactions to prevent a merchant presenting the transaction with a different value after actually tapping the card.) I think a lot of "pay at pump" fuel stations require a full insertion of the card to pre-authorize a large amount, then release it as a partial refund once the amount of fuel dispensed is known. Would this be a barrier to EV charging, if you need a way to communicate this upfront, or have to effectively replicate out EMV infrastructure on totally unmonitored terminals with PIN readers (and likely the next card skimming scandal brewing)? Also, how would contactless-only work for cards that get soft locked to be inserted for a PIN check? Would there be a way for EV chargers to be exempted from this? Or would people end up stuck and unable to charge as there's no available place with a PIN reader they can use to unlock their contactless payments?

baloki 3y ago
They generally pre-auth for either £20 or £40 and then update the amount post-transaction. In terms of PIN check, the card is just declined with an appropriate error message because you can’t insert it and the next time you use a contactless machine it asks for the card to be inserted and a PIN entered. For petrol (gas) pumps in the UK it generally auths either £1 or £99.
- g_p 3y ago
  Makes sense and matched my understanding of the pay at pump preauth for a fixed amount. I guess the issue then becomes relying on contactless (only) without the hardware for full EMV with PIN, as then someone whose card has been used contactless one too many times can't charge, and potentially ends up stuck there. It does feel like contactless is a good convenience measure, but probably isn't ideal as the only mechanism on a reader for charging infrastructure. Unrelated to this, but not being able to initiate charging without internet access (for online auth of cards, and the ones that can only be used online) also is likely to become an issue in rural areas, as well as give quite a few resilience issues if cloud infrastructure isn't available, or internet backhaul from the area is disrupted. Even once power is restored after a storm, if comms are down (like with Storm Arwen), this doesn't sound ideal for EV charging...
- aaronmdjones 3y ago
  I only have experience with Shell, Morrisons, and Tesco pay-at-pump stations. In all of those, you have to physically insert your card and type in your PIN; contactless does not exist.
tharkun__ 3y ago
What's a large amount? I haven't inserted my card at Costco for a very long time now. Just tap. If the pump pre-authorizes an amount (many non-Costco gas stations I go to make you choose an amount to authorize) it simply never captures more than was actually used. Now why would any of this be fundamentally different for EVs? You have a rough gauge for how much "fuel" i.e. "juice" you need, pre-authorize enough money but only capture what actually got used. Done. Why do EVs need to be special?
sitharus 3y ago
Pay-at-pump is ubiquitous here in New Zealand, I don't think I've seen a station without it for years. This may be because around 90% of all retail transactions are done with payment cards here. It's easy. You select the max amount (up to NZ$200), tap your card, and it's done. Pick up the right fuel nozzle, refuel, and go. Exactly the same can be done on EV chargers. The process card-side is not a charge-and-refund as refunds have fees to the merchant. Rather it's a pre-authentication and finalisation. Pre-auth holds the funds for a set time (determined by the merchant agreement with the bank) and the vendor can finalise the charge up to the pre-authentication amount. Most hotels and car rental places do this for security deposits as well, if they don't charge or explicitly cancel your bank will release the fund hold at the end of the holding period.
Symbiote 3y ago
Public transport transactions (where the reader is directly on the ticket gate) are exempted from the soft lock, so maybe EV chargers could be too. At least for small amounts.
- g_p 3y ago
  That makes good sense to exempt those kinds of readers from the soft lock. And given that's possible, it would likely make sense for some similar kind of leeway on EV charging. Not that there's likely to be any real repercussions in many places given a lack of criminal enforcement around theft/fraud, but EV charging requires the user of the stolen card to stick around in a given area to charge the car, so it's likely lower risk than other places where a stolen card can be used for a large transaction in a short period of time. I imagine you'd eventually get some people going around offering people "cheap" EV charges for free (for cash), and then tapping a stolen card on the reader, but there's always going to be someone trying to exploit stolen cards in innovative ways.
Ajedi32 3y ago
I'm not sure how it works at the protocol level, but I've been using contactless payments at gas stations here in the US for years now. You just tap to pay before you start pumping, then after you're finished you get charged for the amount of fuel dispensed.

by g_p 3y ago

baloki 3y ago

They generally pre-auth for either £20 or £40 and then update the amount post-transaction. In terms of PIN check, the card is just declined with an appropriate error message because you can’t insert it and the next time you use a contactless machine it asks for the card to be inserted and a PIN entered. For petrol (gas) pumps in the UK it generally auths either £1 or £99.

g_p 3y ago
Makes sense and matched my understanding of the pay at pump preauth for a fixed amount. I guess the issue then becomes relying on contactless (only) without the hardware for full EMV with PIN, as then someone whose card has been used contactless one too many times can't charge, and potentially ends up stuck there. It does feel like contactless is a good convenience measure, but probably isn't ideal as the only mechanism on a reader for charging infrastructure. Unrelated to this, but not being able to initiate charging without internet access (for online auth of cards, and the ones that can only be used online) also is likely to become an issue in rural areas, as well as give quite a few resilience issues if cloud infrastructure isn't available, or internet backhaul from the area is disrupted. Even once power is restored after a storm, if comms are down (like with Storm Arwen), this doesn't sound ideal for EV charging...
aaronmdjones 3y ago
I only have experience with Shell, Morrisons, and Tesco pay-at-pump stations. In all of those, you have to physically insert your card and type in your PIN; contactless does not exist.

tharkun__ 3y ago

What's a large amount? I haven't inserted my card at Costco for a very long time now. Just tap. If the pump pre-authorizes an amount (many non-Costco gas stations I go to make you choose an amount to authorize) it simply never captures more than was actually used. Now why would any of this be fundamentally different for EVs? You have a rough gauge for how much "fuel" i.e. "juice" you need, pre-authorize enough money but only capture what actually got used. Done. Why do EVs need to be special?

sitharus 3y ago

Pay-at-pump is ubiquitous here in New Zealand, I don't think I've seen a station without it for years. This may be because around 90% of all retail transactions are done with payment cards here. It's easy. You select the max amount (up to NZ$200), tap your card, and it's done. Pick up the right fuel nozzle, refuel, and go. Exactly the same can be done on EV chargers. The process card-side is not a charge-and-refund as refunds have fees to the merchant. Rather it's a pre-authentication and finalisation. Pre-auth holds the funds for a set time (determined by the merchant agreement with the bank) and the vendor can finalise the charge up to the pre-authentication amount. Most hotels and car rental places do this for security deposits as well, if they don't charge or explicitly cancel your bank will release the fund hold at the end of the holding period.

Symbiote 3y ago

Public transport transactions (where the reader is directly on the ticket gate) are exempted from the soft lock, so maybe EV chargers could be too. At least for small amounts.

g_p 3y ago
That makes good sense to exempt those kinds of readers from the soft lock. And given that's possible, it would likely make sense for some similar kind of leeway on EV charging. Not that there's likely to be any real repercussions in many places given a lack of criminal enforcement around theft/fraud, but EV charging requires the user of the stolen card to stick around in a given area to charge the car, so it's likely lower risk than other places where a stolen card can be used for a large transaction in a short period of time. I imagine you'd eventually get some people going around offering people "cheap" EV charges for free (for cash), and then tapping a stolen card on the reader, but there's always going to be someone trying to exploit stolen cards in innovative ways.

Ajedi32 3y ago

I'm not sure how it works at the protocol level, but I've been using contactless payments at gas stations here in the US for years now. You just tap to pay before you start pumping, then after you're finished you get charged for the amount of fuel dispensed.