core_ferc1__yearly_hydroelectric_plants_sched406
Return to SearchAnnual time series of plant statistics for large hydroelectric generating plants.
- Most-recent data:
2025
- Processing:
Data has been cleaned and organized into well-modeled tables that serve as building blocks for downstream wide tables and analyses.
- Source:
FERC Form 1 -- Annual Report of Major Electric Utilities (Schedule 406)
- Primary key:
This table has no primary key. The best approximation for primary keys for this table would be: report_year, utility_id_ferc1, plant_name_ferc1. FERC does not publish plant IDs. The main identifying column is plant_name_ferc1 but that is a free-form string field and there are duplicate records.
Usage Warnings
The plant_type and construction_type are standardized into categorical values from free-form strings.
FERC does not restrict respondents to report unique and non-duplicative plant records. There are sporadic instances of respondents reporting portions of plants and then the total plant (ex: unit 1, unit 2 and total). Use caution when aggregating.
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
Large plants have an installed nameplate capacity of more than 10 MW.
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.
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.
Four-digit year in which the data was reported.
Name of the plant, as reported to FERC. This is a freeform string, not guaranteed to be consistent across references to the same plant.
FERC Licensed Project Number.
Type of plant.
Type of plant construction ('outdoor', 'semioutdoor', or 'conventional'). Categorized by PUDL based on our best guess of intended value in FERC1 freeform strings.
Year the plant's oldest still operational unit was built.
Year the plant's most recently built unit was installed.
Total installed (nameplate) capacity, in megawatts.
Net peak demand for 60 minutes. Note: in some cases peak demand for other time periods may have been reported instead, if hourly peak demand was unavailable.
Hours the plant was connected to load while generating in the report year.
Net plant capability under the most favorable operating conditions, in megawatts.
Net plant capability under the least favorable operating conditions, in megawatts.
The average number of employees assigned to each plant.
Net electricity generation for the specified period in megawatt-hours (MWh).
Cost of plant: land and land rights (USD).
Cost of plant: structures and improvements (USD).
Cost of plant: reservoirs, dams, and waterways (USD).
Cost of plant: equipment (USD).
Cost of plant: roads, railroads, and bridges (USD).
Asset retirement cost (USD).
Total cost of plant (USD).
Cost of plant per megawatt of installed (nameplate) capacity. Nominal USD.
Production expenses: operations, supervision, and engineering (USD).
Production expenses: water for power (USD).
Production expenses: hydraulic expenses (USD).
Production expenses: electric expenses (USD).
Production expenses: miscellaneous power generation expenses (USD).
Production expenses: rents (USD).
Production expenses: maintenance, supervision, and engineering (USD).
Production expenses: maintenance of structures (USD).
Production expenses: maintenance of reservoirs, dams, and waterways (USD).
Production expenses: maintenance of electric plant (USD).
Production expenses: maintenance of miscellaneous hydraulic plant (USD).
Total production expenses, excluding fuel (USD).
Total production expenses (USD per MWh generated).