Charging software and OCPP

• What it runs
• OCPP
• Hardware and payments
• What it costs
• Free or premium
• Getting found
• Support

The backend runs the station

It goes by many names: backend, back office, charge management software, CSMS, "the network." They all mean the same thing, a server somewhere that every one of your chargers reports to. The charger moves the electrons. The backend does everything else.

• Authorization. Every card tap, app start and RFID badge is a question the charger asks the backend. The backend says yes or no.
• Pricing and billing. Your price per kWh, session fees, idle fees and time-of-day rates live here, and so does the math that turns a meter reading into a charge on someone's card.
• Management. Live status, fault alerts, remote resets, firmware updates and power limits. This is how you fix a charger without driving to it.
• Reporting. Sessions, energy, revenue and uptime. Your lender, your grant program and your own curiosity will all ask for these.
• Visibility. Whether drivers can find your chargers in the apps and maps they already use.

So when you choose a backend you're choosing who holds the keys to your site. Know what you're signing, how it works with your hardware, and how it works with the way you want to take payment. Those three, in that order.

OCPP: what it is

OCPP, the Open Charge Point Protocol, is the language a charger and a backend speak to each other. It's an open standard run by an industry group, the Open Charge Alliance, and nearly every charger you can buy for a commercial site speaks it. The charger opens a connection to a web address stored in its settings, and the two trade short messages: I'm awake, someone wants to charge, here's the meter, I've stopped.

The promise is simple. If the charger and the software both speak OCPP, you can swap either one without replacing the other. Hardware from one company, software from another, and the freedom to fire either.

The versions, briefly

What it isn't

• It isn't a payment system. OCPP carries "is this driver allowed" and "here's the meter." The card reader, the processor and the bank are a separate chain, bolted on by whoever integrated your setup.
• It isn't roaming. Letting another network's app start your charger is a different protocol, OCPI, running between backends.
• It isn't the car. The car and the charger talk over the cable in their own languages. OCPP never hears that conversation.
• It isn't a guarantee. "OCPP compliant" on a brochure means somewhere between "certified and tested with your backend" and "an intern once saw it connect." Vendors also add their own extensions, and the features you care about most may live in those.
• It isn't a business model. The protocol is free. Nothing in it says what the software costs, who gets paid first, or who picks up the phone.

Open only counts if you hold the keys

OCPP gives you the right to leave. Whether you actually can comes down to a few dull details, and you want them in writing before you buy anything.

• You, the owner, can change the backend address on the charger yourself, without a fee and without asking permission.
• The charger connects straight to your backend, not through the manufacturer's cloud with your backend hanging off the end of it.
• This charger model, on this firmware, has been run with this backend at real sites. Ask for one you can call.
• Your session data is yours and exports in bulk.

How it fits the charger and the card reader

Three boxes have to agree before anyone gets a kWh: the charger, the backend and the payment terminal. Each is usually made by a different company, and the place where they meet is the place sessions go to die.

There are two common ways to wire it. In one, the card terminal reports to the backend, and the backend tells the charger to start. In the other, the terminal talks to the charger directly and the backend only hears about it afterwards. Both work. What matters is that somebody has done it before with your exact combination, and that you know the answers to a short list.

• Which card terminals does this backend work with, on this charger, today? Not on the roadmap. Today.
• Whose name is on the driver's card statement, and who handles a refund?
• Who holds the money between the tap and your bank account, and how many days does it sit there?
• Can drivers pay by card without downloading anything? Federal funding rules and a growing number of states now expect it. Drivers always did.
• If you bring your own processor, does the backend still charge its transaction fee?

The card tap itself has more handoffs than you'd guess. How charging works steps through them.

What it costs, and who pays

Backend pricing comes in a handful of shapes, usually stacked on top of each other. Get every one of them on a single page before you compare two quotes.

• A fee per port. Monthly or yearly, per connector, owed whether it sold one session or a thousand.
• A fee per session. A flat amount each time someone charges.
• A share of revenue. A percentage of every dollar, on top of card processing.
• Setup and activation. One-time charges per charger or per site.
• Add-ons. Load management, roaming, a branded app, fleet billing and API access are often priced separately. So is the SIM card.
• The term. Multi-year contracts with automatic renewal and an annual increase are common. Read the exit clause before the feature list.

Then there's the question of who pays. Some backends bill you. Others cost you nothing and add a service fee to the driver's session instead. That second kind is free on your statement, but the driver sees one number at the plug, and it's higher than the price you set.

Pricing flexibility belongs in the same conversation. You want to be able to charge by the kWh, add a session fee or an idle fee, run a cheaper overnight rate, and give your own fleet or tenants a different price than the public. If any of those is an upgrade, you want to know now.

Whatever the number is, it's an operating cost. It comes out before you do, every month, and it belongs in the pro forma next to the electric bill. For a small site it's also one of the few costs you can choose not to have.

Free, plain and premium

Strip the logos off and there are three kinds of backend.

• The one that comes with the card reader. Several payment terminal companies include charger management with the terminal. It usually costs the operator nothing, because the driver pays a service fee on each session. It takes cards, sets a price, shows you what's online and sends you the money. For an independent with a few public ports, that's the whole job.
• The plain subscription. A flat fee per port and not much else. You get proper remote tools, pricing rules, exports and usually a choice of payment hardware. No revenue share, no app with your logo on it.
• The full platform. Branded driver app, roaming agreements, fleet accounts and invoicing, load management across sites, energy and battery controls, an API for everything. Built for companies running networks, and priced like it.

The premium platforms are good at what they do. The question is whether you do any of it. Most independent operators with one or two sites will pay for a great many features to use four of them. A few things do push you up the ladder: grant money with reporting rules, fleets that need badges and invoices, more chargers than the building's power can run at once, or a real plan to have your own brand in drivers' pockets.

And free has its own fine print. The driver's fee makes your price look higher than the one you set, you're tied to that terminal, and the feature list ends where it ends. Go in knowing that, and it's a perfectly sensible place to start. You can move up later, provided you kept the keys.

Getting found

A charger nobody can find sells nothing. Drivers look in three places: the map on their phone, a charging app, and the navigation screen in the car. Getting into all three is partly the backend's job and partly yours.

• The listing. Your site's address, connector types, power and price. You can add this yourself, for free, to PlugShare, to Google and Apple maps through a business listing, and to the Department of Energy's station locator, which a lot of other apps copy from.
• The live feed. Whether each plug is free, busy or broken right now. This only comes from the backend. Some publish it to the big maps and to carmakers' navigation as standard, some charge for it, and some don't do it at all.
• Roaming. Whether a driver can start your charger from an app they already have. Useful on a highway. Rarely essential at a site where everyone pays by card.

Ask each backend exactly where your live status will appear, and ask to see a site of theirs showing up there. A green dot on the driver's map is the cheapest advertising you'll ever get. A stale listing that says "available" over a dead charger is the most expensive.

Support is your job

Every backend has a support line. It's there to support you, the operator, when the software misbehaves. It is not there for the driver standing at your charger at 9pm with 6% battery, whatever the sales deck says. That driver doesn't know or care whose software it is. They know whose parking lot it is.

So set it up as if nobody is coming, because nobody is.

• Put a phone number on the charger that reaches a person who can do something. Yours, or someone you pay.
• Make sure that person has a login that can restart a charger, start a session remotely and issue a refund.
• Turn on alerts for faults and offline chargers, and send them to a phone that gets looked at.
• Know the backend's response time for you, and get it in the contract.

When you're ready to sit across the table from a vendor, Buying has the questions to ask and what a good answer sounds like.