An ENTSO-E API alternative that speaks JSON, not zipped XML
The ENTSO-E Transparency Platform is a fantastic free data source — we build on it ourselves, with attribution. But its API returns zipped IEC-62325 XML, paginates at 200 documents, renumbers sequences after market changes, and leaves resolution seams, revisions and gap-filling to you. Voltcast does that plumbing once, correctly, and serves clean, normalized JSON — plus everything the TP does not have: benchmarked forecasts, webhooks, carbon intensity and optimization.
| ENTSO-E Transparency API | Voltcast | |
|---|---|---|
| Format | Zipped IEC-62325 XML documents | Clean JSON, one schema for every zone |
| Price | Free | Free tier; paid from €9/mo — you pay for the plumbing, not the data |
| 15-min MTU seam (Oct 2025) | Sequence renumbering broke most clients | Handled once, flagged per row (resolution_flag) |
| Gaps & curve types | A03 curve-type gaps left to you | Gap-filled and validated, drift-checked daily vs SMARD |
| German imbalance (reBAP) | Not on the platform at all | Included via netztransparenz.de |
| Forecasts | None | P10/P50/P90, accuracy published daily, credit if we lose to baseline |
| Push | None (poll and hope) | Webhooks <60s after auction + SSE stream |
| Rate limits | 400 req/min, hard bans | Predictable per-tier limits with honest headers |
Comparison reflects publicly documented capabilities as of July 2026. Corrections welcome: [email protected].
Three lines to your first price curve
curl -H "Authorization: Bearer YOUR_API_KEY" \ "https://voltcast.com/api/v1/prices/DE-LU?from=2026-07-10&to=2026-07-12"
Frequently asked
Is Voltcast a replacement for the ENTSO-E Transparency Platform?
For most API users, yes: the same underlying day-ahead prices (we record dual-source from ENTSO-E and SMARD with drift validation), normalized to UTC and 15-minute periods, in JSON. Data is served with ENTSO-E attribution. If you need raw XML documents or datasets we do not carry yet, the TP remains the source.
How does Voltcast handle the October 2025 15-minute MTU switch?
Every price row carries an explicit resolution_flag (PT15M or PT60M). History before the seam is hourly, after it 15-minute native, and the API can aggregate to hourly on request — no client-side sequence guessing.
Does Voltcast add anything the ENTSO-E API does not have?
Yes: probabilistic price forecasts with publicly benchmarked accuracy, negative-price risk, webhooks and SSE push, German reBAP imbalance prices (not on the TP), GB data via Elexon, FCR/aFRR/mFRR reserve prices, carbon intensity, optimization endpoints, bulk parquet export, SDKs and an MCP server for AI agents.
Is the ENTSO-E data license respected?
Yes. Data is served under the Transparency Platform terms with attribution on every response, and our data-licensing page documents exactly what is redistributed and under which conditions.
Check our accuracy before you commit.
Every forecast we sell is benchmarked in public, every day, against a free baseline — and if we don't beat it in your zone, that zone is free. That's in the terms.
30 seconds · no credit card · free zone forever