{
  "_doc": "Median installed cost, USD per watt DC, before any incentive. NULL means we have not verified it: the engine falls back to the national figure and flags the result. Never invent a state value here.",
  "_source": "ONE source for every modelled state value: EnergySage Marketplace state pages, read 2026-09-05 (pages dated 2026-08-28). Each record carries its own source and verified_on. Never mix sources inside usd_per_watt: a ranking built on two sources ranks the sources. lbnl_2023 is reference-only and carries its own source.",
  "_verified_on": "2026-09-05",
  "_national_usd_per_watt": 2.6,
  "_national_source": "https://www.energysage.com/local-data/solar-panel-cost/",
  "_national_source_note": "EnergySage Marketplace national average before incentives (12 kW typical system, $31,135); page updated 2026-06-30",
  "_national_verified_on": "2026-09-05",
  "_price_basis": "usd_per_watt is the MODELLED value: 2026 marketplace quote averages from one source for every state. lbnl_2023 is the REFERENCE value: LBNL Tracking the Sun medians for systems installed in 2023 (2023 dollars). The two differ by roughly 60% by methodology: Tracking the Sun records prices as reported in permit and incentive data across all installers and equipment tiers; marketplace quotes are competitive bids. Decision 2026-09-05: model on the marketplace basis and SHOW BOTH everywhere (engine: result.altBasis; pages: two payback lines). Never mix the two inside usd_per_watt; never interpolate a missing reference value.",
  "_basis_labels": {
    "modelled": {
      "label": "competitive quoted prices",
      "short": "EnergySage 2026"
    },
    "reference": {
      "label": "typical reported prices",
      "short": "LBNL 2023"
    }
  },
  "_lbnl_note": "IL and PA have no LBNL state median: the slide shows a state only with at least 20 observations.",
  "states": {
    "CA": {
      "usd_per_watt": 2.48,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/ca/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.2,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "MA": {
      "usd_per_watt": 2.91,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/ma/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 3.9,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "TX": {
      "usd_per_watt": 2.22,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/tx/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.1,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "NY": {
      "usd_per_watt": 2.76,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/ny/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.5,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "CT": {
      "usd_per_watt": 2.72,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/ct/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.6,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "IL": {
      "usd_per_watt": 2.98,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/il/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": null,
        "note": "fewer than 20 observations, so LBNL publishes no median for this state",
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "verified_on": "2026-09-05"
      }
    },
    "NJ": {
      "usd_per_watt": 2.58,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/nj/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.8,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "MD": {
      "usd_per_watt": 2.62,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/md/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.3,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "PA": {
      "usd_per_watt": 2.58,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/pa/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": null,
        "note": "fewer than 20 observations, so LBNL publishes no median for this state",
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "verified_on": "2026-09-05"
      }
    },
    "AZ": {
      "usd_per_watt": 2.21,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/az/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    },
    "FL": {
      "usd_per_watt": 2.12,
      "estimated": false,
      "source": "https://www.energysage.com/local-data/solar-panel-cost/fl/",
      "source_note": "EnergySage Marketplace real-quote average, as of Sep 2026; page updated 2026-08-28",
      "verified_on": "2026-09-05",
      "lbnl_2023": {
        "median_usd_per_watt": 4.5,
        "source": "https://escholarship.org/uc/item/2c50c61d",
        "source_note": "LBNL Tracking the Sun 2024 Edition (OSTI 2438480), slide 37, median installed price, residential systems installed in 2023, 2023$/W DC, read from the chart labels",
        "verified_on": "2026-09-05"
      }
    }
  }
}