Payment interface integration

[pisoiu]

Hi friends,
I designed as an outsourced project for another company a type2 charging station for EV, just hardware part. Nothing fancy about it, basic functions implemented with ESP32, few relays, a NFC reader for charging activation, a small display, etc.
But I may need to think to extend this into a direction I know nothing about, meaning NFC payment integration. I see that EU wants to implement mandatory payment in all charging stations beginning with 2027 iirc.
What does it mean from a technical point of view to integrate NFC payment, assuming I have in the station a LTE modem and a NFC reader? NFC readers for payment are different than basic NFC readers used just to read a serial # from a card and start charging? What embedded software do I need for that and what CPU is required? Do I need Linux or a freeRTOS with ESP32 will do the job? Will I need a normal CPU or do I need secure CPU? Are some specific certifications required for this, for hardware or software?
If somebody is knowledgeable in this area please give me some hints.
Thank you.

[bateau020]

NFC payment in reality has 2 parts: the actual communication with the NFC enabled payment method (card or phone), and the communication with the financial institutions. All of that is heavily regulated and not really open for DIY. For the hardware I suggest taking a look at ready made payment terminals that are meant for self service (not all terminals are suitable for self service), as that will be far easier. The ones I mostly work with are from Ingenico, but there are others. And don't underestimate the connectivity to the payment processors.

[Jeroen3]

For the manufacturer of the charging station you call up CCV and ask them for a payment terminal.
These are things you don't want to do yourself, they need to be trusted platforms with secure back-end and integration with international payment processors.

Basically it's a tamper proofed device with processor that talks to the payment backend.
10 years ago they ran embedded linux and their platform was c# based. _{They recruited agressively at university.}

[jbb]

I used to work in the industry (not any more, and I don't have any financial interest), and I can say... don't try to do it yourself.  It's a nightmare of complexity and regulation.  Suffice it to say that getting FCC certification for an intentional radiator was a pleasantly easy part of the process.

Thus, plan to buy or rent one.  You'll get a box you bolt onto the front of your charging station.  It will require some specific cutouts on your front panel and maybe special considerations for an anti-removal device.  If you're fitting a PIN pad, that may need even more specific mounting to shield the PIN pad from view.

I recommend finding a payment company which:

• provides the card reader hardware, software and key loading and the payment processing services
• has PCI certified products, preferably includingSecure Reading and Exchange of Data (SRED) and maybe Point To Point Encryption (P2PE) so that you never have to handle unencrypted credit card details (a responsibility you Do Not Want)
• has adequate documentation and support on how to integrate the payment card terminal into your device. Regrettably, you may need to sign an NDA to see the documentation
• operates in all the countries you wish to cover
  Note: in my opinion, this is less important than getting adequate support!

[Bud]

Payments is a regulated industry. It is Not for a DIY project. You need certifications.

[pisoiu]

I never mentioned DIY. The project I made is commercial but I may need to address it into a direction in which I have no experience, hence the request for information. Which is very valuable by the way, thanks to all for sharing the insights.