Data sources — energy — Energy

Every source the energy work uses, what it covers, and what its licence actually permits.

Fraunhofer ISE — Energy-Charts

https://api.energy-charts.info

Declared per response in a license field, and stored in every provenance sidecar rather than assumed once. For Portugal and Spain this is a re-serve of ENTSO-E, not an independent national-TSO pull.

Three endpoints are used, and they are not interchangeable:

• /v2/public_power — public net electricity production, in MW
• /v2/cbet — cross-border scheduled commercial exchanges, in GW
• /v2/cbpf — cross-border physical flows, in GW

cbet is a day-ahead nomination and cbpf is a meter reading. They differ by up to 900 MW in a single hour. Which one a figure uses is stated on the figure.

/v2/total_power — which would include industrial self-supply — exists only for Germany.

France, Germany and Italy carry /v2/public_power only. The cross-border series are not archived for them: the comparison reads shares of load and prices, and Germany's quarter-hourly exchanges alone would double the archive for a series nothing plots.

Bundesnetzagentur — SMARD.de, via Energy-Charts

https://www.smard.de

The same /v2/price endpoint that serves Iberian prices for private use only serves these three zones under CC BY 4.0, because the upstream is different: Energy-Charts relays SMARD, the German regulator's open-data platform, and the licence field of the response says so. The archive asserts that field on every fetch and refuses to store a response that does not begin CC BY 4.0, so a quiet change of terms fails the job rather than the reuse.

One zone stands for each country. Germany and Luxembourg are one zone. Italy has six and no national price on this source; IT-North is the largest by demand and is what "Italy" means on the comparison.

OMIE

https://www.omie.es

The legal notice states that public, free-of-charge information "can be used freely, provided that its original content is fully respected" and that "you must cite the source". No commercial restriction. OMIE is the rights-holder for MIBEL day-ahead prices, which is why this is the source rather than a republisher.

Two traps: the filename's .1 suffix is a version counter, and on re-run days the earlier version is deleted — so the filename is resolved from OMIE's own index, never constructed. And both price columns are timestamped in Spanish peninsular time, including the Portuguese one.

Sources deliberately not used, and why

Energy-Charts /v2/price — serves the Iberian day-ahead price, but the response declares "The data provided herein is for private and internal use only." Usable for analysis, not republishable. It is used here only as an independent cross-check against OMIE, never as a published series. The Portuguese and Spanish prices on the country comparison are OMIE's; only the French, German and Italian ones come through this endpoint, and those carry SMARD's CC BY.

ENTSO-E Transparency Platform — publishes a subset of its data under CC BY 4.0 via an explicit list. Article 12.1.d, day-ahead prices, is not on that list, and anything off it falls under a clause requiring the prior agreement of the copyright holder. Free access is not an open licence.

Ember — carries Iberian hourly prices back to 2015 under a blanket CC BY 4.0, and cross-checks against OMIE exactly. But its stated upstream is ENTSO-E, which is precisely the data ENTSO-E does not place under CC BY, and Ember publishes no carve-out explaining that. Used as a validation series, never as a source of record.

ESIOS, REData, REN, OMIP — each is either non-commercial only, prohibited by default, or silent on reuse. Checked and rejected.

Attribution

Electricity system data by Fraunhofer ISE / Energy-Charts (energy-charts.info), CC BY 4.0. Iberian day-ahead price data by OMIE (omie.es). French, German and Italian day-ahead price data by Bundesnetzagentur | SMARD.de (smard.de), CC BY 4.0, via Energy-Charts.