Netherlands grid capacity API
The Dutch capaciteitskaart, by area and by postcode
The Netherlands publishes one national capacity map for TenneT and the regional grid operators. Its areas are defined by postcodes rather than coordinates, so the API answers the question a Dutch project actually starts with: what serves this postcode?
Free plan, 250 requests a month, no card.
Congestion is the answer, not a number
The national map publishes, per supply area and per direction, the existing transport capacity, the capacity already needed by existing contracts, the waitlist in MW and in requests, a congestion colour and the year congestion is expected to be solved. It does not publish headroom, and the operators' own guidance is that the colour, not arithmetic on the other figures, decides whether capacity can be allocated.
So the API serves each figure as its own measure, with the congestion colour as a status and the operators' label beside it, and never subtracts one figure from another to invent a headroom the operators did not publish.
What the national map publishes
- Per supply area and per direction (offtake and injection): existing transport capacity and the capacity required by existing contracts, in MW.
- The waitlist, in MW and in unique requests, and a congestion colour with the expected year it is solved.
- Areas as sets of six-character postcodes; the map publishes no station coordinates.
- A TenneT (high-voltage) layer and a regional-operator (medium-voltage) layer, which can cover the same postcode.
Endpoints
| Method | Path | Returns |
|---|---|---|
| GET | /v1/postcodes/NL/{postcode} | The areas that serve a postcode, with their current records. |
| GET | /v1/capacity/search?country=NL | Every Dutch record, filterable by direction and status. |
| GET | /v1/operators?country=NL | The Dutch operators and the national platform. |
Example
Request
curl "https://api.gridcapacityapi.com/v1/postcodes/NL/7471AA" \ -H "Authorization: Bearer gc_live_..."Six-character postcodes (PC6). A postcode can be served by more than one area — a TenneT area and a regional one — and each is returned with its own records.
Response shapeplaceholder values — not a capacity claim
{
"data": {
"country": "NL",
"postcode": "7471AA",
"areas": [
{
"asset": {
"id": "area_…",
"type": "area",
"name": "…",
"country": "NL",
"operator": {
"slug": "…",
"name": "…",
"type": "DSO"
},
"location": null
},
"source_id": "nl_…",
"capacity": [
{
"direction": "offtake",
"capacity": {
"type": "…",
"value": null,
"unit": "status",
"value_mw": null,
"status": "…",
"status_label": "…"
},
"horizon": {
"type": "snapshot",
"year": null,
"label": null
},
"access": {
"status": "…"
}
}
]
}
]
},
"meta": {
"request_id": "req_…"
}
}What the API holds today
Read from the API as this page renders. A source is listed with its rights status, because a listed source is not always a served one.
What people build with it
Postcode checks
Answer “is there congestion here?” for any Dutch address, for both offtake and injection, in one call.
Waitlist monitoring
Follow the queue and the expected solution year per area as the map is republished.
Portfolio screening
Run a list of postcodes through the lookup and group sites by the areas that serve them.
Questions
Why is there no available-capacity figure?
Can I look up a four-digit postcode?
Are the TenneT figures served?
Start building on grid-capacity data
A key in under a minute, on the Free plan.