Search and download FERC interconnection docket filings programmatically from the FERC eLibrary to track generator interconnection study progress

Verified steps

1. Access the FERC eLibrary General Search at https://elibrary.ferc.gov/eLibrary/search; eLibrary does not expose a documented public REST API — structured data extraction requires either using the web search form with specific parameters or using the FERC eLibrary file list endpoint.
2. Use the eLibrary File List endpoint at https://elibrary.ferc.gov/eLibrary/filelist with query parameters such as docket_number (e.g., 'ER25-1234'), date_range, and document_type to retrieve a structured XML or CSV list of filings for a specific docket.
3. For interconnection queue monitoring, filter by docket_number prefix 'ER' (electric rate filings including interconnection agreements) or 'EL' (electric litigation/complaint dockets for interconnection disputes); new interconnection agreement dockets filed under Order 2023 rules will appear under the transmission provider's docket series.
4. Parse the file list response to extract accession_number, filed_date, description, and document_url for each filing; download individual documents using the constructed URL pattern https://elibrary.ferc.gov/eLibrary/filelist?accession_num={accession_number}.
5. For bulk monitoring of newly filed interconnection documents, set up an eSubscription via FERC's eSubscription service (https://ferconline.ferc.gov/eSubscription.aspx) to receive email notifications when new documents are filed on specific dockets; use these notifications to trigger targeted eLibrary downloads.
6. Respect FERC's system policies: the eLibrary web interface is intended for human access; automated bulk downloads should be throttled to avoid overloading the system — introduce delays between requests and avoid downloading documents that are not needed for your use case.