Choosing a MID charger: what to look for (and the hidden cost)

For ERE you need a charger with a built-in, certified MID meter. Since the Energy for Transport Regulation 2026, only the certified meter in the supply point itself counts for home charging • an external MID sub-meter is no longer allowed. So far the familiar requirement. Most buying guides stop there.

There is a second question that is less visible, and that can cost you money: who can access your charging data, and at what price?

The obvious requirements

Three things almost everyone agrees on:

• A built-in MID meter. Without a certified meter on board, no ERE. A separate sub-meter no longer counts.
• Works with the registration provider of your choice. Your charger must not lock you into a single party.
• No mandatory subscription to use your own charger or your own data.

You will find those points in every comparison. The fourth almost never makes the list.

The less visible: what does it cost to reach your own data?

After charging, your sessions sit on the manufacturer's platform. To turn them into ERE, your registration provider reads them there • on your authorisation, through that manufacturer's API. That access almost always costs something. The question is not whether, but how.

What API access really costs

At most manufacturers it is a transparent, flat or per-read rate. Two examples of brands we connect with:

• Enphase charges per API plan: free up to 1,000 calls per month, then $249 per month for 50,000 calls, and $0.005 per extra call (source: Enphase developer plans).
• Tesla charges per use through the Fleet API: about $0.0001 per streamed signal and $0.002 per data read, with $10 of free credit per month.

Work it out per customer and it comes to cents per month to read someone's sessions • a normal platform cost the registration provider carries, and a negligible part of what those charging sessions earn. Not something that should appear on your bill per kWh.

The difference: a platform cost, or a toll on your data

This is the dividing line. A flat or per-call rate the provider pays is a cost of a few cents. A commission or a fixed amount per customer to "unlock data at scale" is something else entirely: not a technical cost of cents, but a cut of the value that scales with every customer. And that amount does not disappear • through a higher service fee or a lower payout it ends up with you.

In other words: then you are paying, indirectly, to reach your own data. The ERE accrues to you, the resident. The charging data is about your sessions. A charger that puts a tollgate in between works against that principle.

How to check this before you buy

You do not need to be a techie to test this. Just ask the seller or manufacturer:

• Can a registration provider of my choice retrieve my charging sessions, on my authorisation?
• Are there costs involved that land with me or my provider, and is that a flat or per-call rate, or an amount per customer?
• If not, is there a validated export I can download myself?

A transparent, flat or per-call rate is a fine answer. A per-customer commission on your own data is a red flag.

Where we stand

We connect with most charger brands. With our largest data sources, such as Enphase and Tesla, we have stable agreements at these kinds of transparent rates • so the data flows without a per-customer toll. Where a manufacturer's terms come down to you paying to reach your own data, we say so and look for a route that keeps your data yours.

Because that is the whole idea: your kilowatt-hours, your data, your revenue.

Not sure whether your charger meets this? Check your charger or request a quote.

Sources

1. Enphase • Developer plans (API pricing)
2. Tesla • Fleet API (developer)