Voltstack Data API

Data API v1

A read-only REST API over the same feed layer the product runs on. Key every request: the data API key goes in the X-API-Key header, and you can request one at research@voltstack.energy. As at 8 August 2026 the /v1 surface is key-gated in full, and a request carrying no key is refused on every path below, current feeds and history alike. Build every integration keyed: a keyed call keeps working whatever happens to anonymous access. Responses are JSON with a live flag and a data-age timestamp, so you can tell exactly what you are looking at, the same honesty rule as /status.

Base URL

https://api.voltstack.energy/v1

Try it (bring a key)

curl -H "X-API-Key: YOUR_KEY" \
  https://api.voltstack.energy/v1/power/day-ahead

History, with its required window

curl -H "X-API-Key: YOUR_KEY" \
  "https://api.voltstack.energy/v1/history/day-ahead?zone=DE_LU&from=2026-01-01&to=2026-07-01"

Without a key, as at 8 August 2026, on every path

HTTP 401
{"error":"api-key-required","detail":"This endpoint requires a data API key in the X-API-Key header. Request one at research@voltstack.energy."}

API KEYAs at 8 August 2026 this applies to every endpoint listed below, current feeds included: there is no open subset to start from, and an unkeyed request is refused on all of them. The badges on individual rows flag the other things a call needs, not the key.

Power

GET/v1/power/day-aheadLIVE
Day-ahead auction prices across 30+ European zones (EPEX, Nord Pool, OMIE, GME via ENTSO-E).
GET/v1/power/flowsLIVE
Cross-border physical flows on the major interconnectors.
GET/v1/power/generation?country=DE&range=1WLIVE
Generation mix by fuel type. GB is served from Elexon; other zones from ENTSO-E.
GET/v1/power/merit-order?country=DELIVE
Merit-order curve snapshot for a zone.
GET/v1/power/imbalanceLIVE
Imbalance prices (ENTSO-E, dual-price zones included).
GET/v1/power/imbalance-deLIVE
German AEP imbalance price estimator (netztransparenz.de).
GET/v1/power/grid-stressLIVE
German redispatch volumes and costs (netztransparenz.de).
GET/v1/power/balancing-stressLIVE
German balancing-energy stress indicator.
GET/v1/power/constraintsLIVE
JAO flow-based market coupling constraints.
GET/v1/power/ummLIVE
REMIT urgent market messages (outages and capacity events).
GET/v1/power/fr-nuclearLIVE
French nuclear fleet availability.
GET/v1/power/nordic-hydroLIVE
Nordic hydro reservoir levels.
GET/v1/power/gb-balancingLIVE
GB balancing mechanism: accepted offers/bids vs MID (Elexon BOD/BOALF).

Gas

GET/v1/gas/storageLIVE
EU gas storage levels and flows (GIE AGSI+).
GET/v1/gas/lngLIVE
LNG terminal inventories and sendout (GIE ALSI+).
GET/v1/gas/pipeline-flowsLIVE
Cross-border pipeline flows (ENTSOG).
GET/v1/gas/gb-systemLIVE
GB gas system: demand, supply mix, linepack (National Gas).

Weather

GET/v1/weather?regions=EU_DE,EU_FR&days=10LIVE
10-day temperature and wind forecasts by market region (Open-Meteo).
GET/v1/weather/forecast-riskLIVE
Forecast-error risk: run-to-run drift on wind and demand.

History

GET/v1/history/day-ahead?zone=DE_LU&from=2026-01-01&to=2026-07-01FROM/TO REQUIRED
Historical day-ahead prices by zone.
GET/v1/history/n2ex-dayahead?from=…&to=…FROM/TO REQUIRED
GB N2EX day-ahead auction history (GBP/MWh, hourly).
GET/v1/history/realized-vol?zone=DE_LU&from=…&to=…FROM/TO REQUIRED
Realized volatility computed from settled prices.
GET/v1/history/gas-storage?from=…&to=…FROM/TO REQUIRED
Historical EU storage levels.
GET/v1/history/lng-terminals?from=…&to=…FROM/TO REQUIRED
Historical LNG terminal data.
GET/v1/history/commodities?from=…&to=…FROM/TO REQUIRED
Commodity reference series (FRED).

Benchmarks

GET/v1/benchmarks/de-bessLIVE
DE battery storage revenue benchmark (reference configuration).
GET/v1/benchmarks/de-bess/customAUTH
Benchmark for your own storage configuration.

Health

GET/v1/health/cross-checksLIVE
Nightly cross-validation of our series against independent sources, with per-series pass/fail.

Documentation

API specification — full request/response shapes for every endpoint.
Data dictionary — every field, unit, and zone code.
Methodology guide — where each series comes from and how derived values are computed.

Provenance

Every series is fetched from its primary source (ENTSO-E, GIE, ENTSOG, Elexon, National Gas, JAO, netztransparenz.de, Open-Meteo, FRED) by a background worker and cross-validated nightly against independent references. The current result is served at /v1/health/cross-checks: key that request like any other. Feed-level freshness and completeness are on /status.