out_ferc1__yearly_transmission_lines_sched422
Annual time series of statistics about transmission lines.
- Most-recent data:
2025
- Processing:
Data has been expanded into a wide/denormalized format, with IDs and codes accompanied by human-readable names and descriptions.
- Source:
FERC Form 1 -- Annual Report of Major Electric Utilities (Schedule 422)
- Primary key:
This table has no primary key. Each record of this table is supposed to represent one stretch of a transmission line, but there are no IDs and many nulls in the fields which would nominally distinguish unique transmission lines.
Usage Warnings
Contains columns which may appear categorical, but are actually free text.
Some columns contain subtotals; use caution when choosing columns to aggregate.
FERC data is notoriously difficult to extract cleanly, and often contains free-form strings, non-labeled total rows and lack of IDs. See Notable Irregularities for details.
Additional Details
Information describing transmission lines, the cost of lines, annual operating and capital expenses, etc. This table includes transmission lines having nominal voltage of 132 kilovolts or greater. Transmission lines below these voltages are required to be reported in group totals only for each voltage.
Columns
Identifier indicating original FERC Form 1 source record. format: {table_name}_{report_year}_{report_prd}_{respondent_id}_{spplmnt_num}_{row_number}. Unique within FERC Form 1 DB tables which are not row-mapped.
Four-digit year in which the data was reported.
PUDL-assigned utility ID, identifying a FERC1 utility. This is an auto-incremented ID and is not expected to be stable from year to year.
FERC-assigned respondent_id from DBF reporting years, identifying the reporting entity. Stable from year to year.
FERC-assigned entity_id from XBRL reporting years, identifying the reporting entity. Stable from year to year.
A manually assigned PUDL utility ID. May not be stable over time.
Name of the responding utility, as it is reported in FERC Form 1. For human readability only.
The starting point of a transmission line.
The end point of a transmission line.
The operating voltage, expressed kilo-volts, for three-phase 60 cycle alternative current transmission lines.
Manufactured (Designed) voltage, expressed in kilo-volts, for three-phase 60 cycle alternative current transmission lines
Supporting structure of the transmission line.
Length (in pole miles or circuit miles (if transmission lines are underground)) for lines that are stand alone structures (whose cost are reported on a stand-alone basis).
Length (in pole miles or circuit miles (if transmission lines are underground)) for lines that are agrregated with other lines / structures (whose cost are aggregated and combined with other structures).
Number of circuits in a transmission line.
Size of transmission conductor and material of the transmission line.
Cost of plant: land and land rights (USD).
Other costs associated with the plant (USD).
Total cost of plant (USD).
Production expenses: operations, supervision, and engineering (USD).
Production expenses: Maintenance (USD).
Production expenses: rents (USD).
Total production expenses, excluding fuel (USD).