RectifHydPlus: Forty Year Hydropower Generation Reanalysis for Conterminous United States, Version 1.1

Overview

This dataset contains monthly hydropower net-generation totals for 590 plants (each >10 MW) across the conterminous United States (CONUS) from 1980 to 2019. RectifHydPlus v1.1 includes one harmonized table of historical monthly generation—backfilled with observed monthly values where available—and two companion tables: (i) an estimates-only version with no backfill and (ii) a hydrological-control version that removes the effects of capacity and operational change. Each table comprises 23,600 records (590 plants × 40 years). The dataset was developed to address temporal gaps and inconsistencies in publicly available hydropower generation data as available through EIA-923 survey reports. Each record includes a quality label denoting the underlying proxy—from best (direct reservoir releases) to weakest (pattern copied from similar years). By combining the agency-reported survey records with observed and simulated hydrologic releases, RectifHydPlus offers complete, quality-labeled monthly estimates suitable for trend analysis and generation of hydropower generation inputs for energy-water modeling.

The files included in RectifHydPlus version 1.1 are as follows:

RectifHydPlus_NetGen_MWh_v1.1.csv: the main RectifHydPlus dataset, containing monthly generating totals for 590 plants (> 10MW) over the forty-year period 1980 – 2019. It includes estimated historical monthly generation, backfilled with EIA observed monthly generation and—new in version 1.1—California Energy Commission data, where available.

RectifHydPlus_v1.1_field_descriptions.csv: Describes and defines the fields present in RectifHydPlus_NetGen_MWh_v1.1.csv, RectifHydPlus_NetGen_MWh_v1.1_NoObservations.csv, and RectifHydPlus_NetGen_MWh_v1.1_NoObservations.csv.

RectifHydPlus_supplemental.zip: supplemental RectifHydPlus tables. Two versions are offered:

1. Estimated historical monthly generation with no backfill from EIA-923 or California Energy Commission observations. This file is named RectifHydPlus_NetGen_MWh_v1.1_NoObservations.csv.

2. Computed monthly generation based on a hydrological control, removing effects of capacity and operational change over the reanalysis period. This file is named RectifHydPlus_NetGen_MWh_v1.1_HydrologicalControl.

RectifHydPlus_misc.zip: contains miscellaneous data supporting RectifHydPlus. This includes a reference table that maps RectifHydPlus ID to other common identifiers, including EIA ID, EHA, and COMPLXID. It also includes a daily, spill adjusted water release time series created for each dam. Users may adopt these time series to create generation totals to any desired aggregation (e.g., weekly total generation). RectifHydPlus does not provide generation totals at finer than monthly temporal resolution as these estimates are difficult to validate given lack of observed hydropower generation data with sub-monthly resolution.

RectifHydPlus_code.zip: contains the code used to generate RectifHydPlus. This is specific release of the code held at the following GitLab repository: https://code.ornl.gov/turnersw/rectifhydplus

RectifHydPlus_inputs.zip: contains all input datasets used to create RectifHydPlus.

Methodology

For each of the 590 CONUS hydropower plants (>10 MW), a daily powered water release time series was constructed using a prioritized proxy stack: (A1) observed reservoir releases (ResOpsUS), (A1) observed river discharge  within ~10 km downstream of the dam, (B1) simulated discharge at the dam (Dayflow v2), targeting run-of-river plants only, (B2) simulated reservoir release from ISTARF driven by DayflowV2, and (C) HUC4 outlet discharge. When no proxy was available, monthly fractions were inferred from hydrologically similar years (D1) or from nearby hydropower plants (D2). A plant-specific spill-quantile cap was calibrated to limit unrealistically high releases prior to aggregation. Daily releases were aggregated to months and normalized within each year to obtain monthly fractions. Generation estimates were derived by downscaling annual EIA observations using the resulting monthly powered-release fractions. The main RectifHydPlus version 1.1 data table   replaces estimated hydropower with observed monthly generation where available (EIA-923 monthly; CEC QFER). For the hydrological-control table, annual generation was computed with an energy-limited capacity-factor model (ELCFC) using contemporary capacity and calibrated parameters, then apportioned to months using the same fractions. Each record includes a quality_label (A1, A2, B1, B2, C, D1, D2) identifying the proxy class and whether the value is observed or downscaled, consistent with the prioritized workflow. Please see Turner et al. (2025) for additional details.