Where our numbers come from

Every rebate estimate, utility rate plan, climate figure, and solar projection you see on the site traces back to one or more of the public and partner sources listed below. This page is the complete list; the short "Data Sources" footer on individual pages is a condensed view of the same information.

Independent platform. WattGap is an independent informational platform and is not endorsed by or affiliated with any data provider listed on this page. Each source has its own terms of use and privacy practices; follow the linked pages for definitive information.

  • Rewiring America

    Rebate data from Rewiring America

  • U.S. Census Bureau

    This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau

  • OpenEI

    CC BY 4.0

    Utility rate data from the NREL Utility Rate Database

  • NASA POWER

    Climate data from NASA POWER (Prediction of Worldwide Energy Resources)

    The data was obtained from National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division.

  • U.S. Energy Information Administration

    Source: U.S. Energy Information Administration

  • NREL PVWatts

    Solar estimates powered by NREL PVWatts, developed by the National Renewable Energy Laboratory for the U.S. Department of Energy. NREL does not endorse WattGap.

  • NREL Utility Companies by ZIP Code

    CC BY 4.0

    Utility attribution derived from NREL's U.S. Electric Utility Companies and Rates: Look-up by Zip Code dataset, compiled from EIA Form 861. NREL does not endorse WattGap.

  • DSIRE

    CC BY-SA 4.0

    Incentive data from DSIRE, NC Clean Energy Technology Center, NC State University

  • Google Solar API

    Rooftop solar analysis powered by Google Solar API

Deeper dives

  • Methodology -- how we combine these sources into your WattGap Score and rebate estimates.
  • Privacy Policy -- what data we collect, what we share with each provider, and your rights under CCPA, CPA, VCDPA, CTDPA, OCPA, UCPA, and GDPR.

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