How to add UPI payment to your existing EV charger

Short answer: if your charger speaks OCPP 1.6 or later and is connected to the internet, it can take UPI payments without any new hardware. The charger is connected to software that runs a payment page, and a QR code goes on each gun. A driver scans it, pays from any UPI app already on their phone, and charges. Only what the session used is taken. If the charger is locked to its maker's own software, it has to be opened up or replaced first.

What your charger needs

• OCPP 1.6 or later. OCPP is the open language chargers use to talk to charging software. It is usually on the spec sheet as "OCPP 1.6J" or "OCPP 2.0.1". Our guide to what OCPP is explains why it matters.
• A way to change the server address. The charger has to be pointed at the new software. On most chargers this is a setting in the charger's own setup page or app; on some only the maker can change it. Ask your current supplier before anything else.
• A working internet connection. 4G, Wi-Fi or a cable. The payment page and the charger meet in the software, so a charger that is often offline cannot take app-less payments reliably.
• Remote start. The software has to be able to start a session on the charger once the driver has paid. Almost every OCPP charger does this, but a few skip the standard start messages. This is what a test charger checks.

A UPI sticker is not the same as UPI charging

The cheapest way to "add UPI" is a printed UPI QR on the charger that pays the owner's account. It works for collecting money, but the charger does not know who paid or how much. Someone has to start the session by hand, nothing stops the charge at the amount paid, and if the driver uses less, getting the difference back is a manual refund.

UPI charging uses a QR that opens a payment page for that one gun. The page knows which charger it belongs to, starts the session once the payment is approved, stops it when the money runs out, and settles only what was used. The charger and the payment are one transaction, so there is nothing to reconcile by hand.

How a session works

1. The driver scans the QR on the gun. A web page opens on their phone. There is no app to download and no account to create.
2. They pick an amount and approve it in any UPI app: Google Pay, PhonePe, Paytm, BHIM and others. The bank holds that amount; nothing is taken yet. This is called a UPI hold.
3. Charging starts. The driver can watch it on the same page.
4. When the session ends, only the cost of the units used is taken. The bank releases the rest, so there is no refund to wait for.

The full walk-through, with a worked example in rupees, is in how UPI charging works.

What changes for you

• Your tariff. You set the price per unit, and can set different prices for the public, your staff or members.
• Every driver can charge. Not only the people who have installed one network's app.
• One dashboard. Sessions, revenue and faults for old and new chargers in one place.
• Your money. You are paid into your bank account. Ask any provider exactly when, and in whose name drivers' payments are collected.

Our side of this is on the UPI charging page and the software page, which lists the four steps to move existing chargers across.

What to ask before you move your chargers

• Which of my charger models have you already connected, and will you test one of mine first?
• Does the driver pay by a hold that settles only what was used, or by a prepayment that needs a refund?
• When am I paid, and is the money collected in my name or yours?
• What is the software fee per charger and the fee per payment, and is there a setup charge?
• If I leave later, can I point the chargers at another provider? With OCPP you should be able to.

More questions worth asking are in questions to ask a charging company before you sign.