{
  "name": "Solar payback JSON endpoint",
  "description": "Returns upfront cost, generator fuel and maintenance savings, campground-night savings, payback years, break-even nights, horizon net value, and ROI estimate for RV solar ownership math.",
  "publisher": {
    "name": "OffGridRVHub",
    "url": "https://www.offgridrvhub.com"
  },
  "source": {
    "endpoint": "https://www.offgridrvhub.com/tools/api/solar-payback.json",
    "fullCalculator": "https://www.offgridrvhub.com/tools/solar-payback-calculator",
    "assumptions": "https://www.offgridrvhub.com/tools/calculator-assumptions",
    "documentation": "https://www.offgridrvhub.com/tools/calculator-api"
  },
  "caveat": "This is a planning estimate for RV education and comparison. It is not electrical, plumbing, safety, or installation advice.",
  "input": {
    "systemCostDollars": 4200,
    "installLaborDollars": 1200,
    "annualMaintenanceDollars": 80,
    "ownershipYears": 6,
    "annualOffGridNights": 45,
    "paidNightsAvoidedPerYear": 12,
    "campgroundSavingsPerNightDollars": 38,
    "generatorHoursAvoidedPerNight": 1.6,
    "generatorFuelGallonsPerHour": 0.22,
    "fuelPricePerGallonDollars": 4,
    "generatorMaintenanceDollarsPerHour": 0.75,
    "replacementValueAvoidedDollars": 600,
    "resaleValueDollars": 900
  },
  "result": {
    "upfrontCostDollars": 5400,
    "effectiveCostDollars": 4800,
    "annualGeneratorFuelSavingsDollars": 63,
    "annualGeneratorMaintenanceSavingsDollars": 54,
    "annualCampgroundSavingsDollars": 456,
    "annualGrossSavingsDollars": 573,
    "annualNetSavingsDollars": 493,
    "generatorHoursAvoidedPerYear": 72,
    "generatorFuelGallonsAvoidedPerYear": 15.8,
    "savingsPerOffGridNightDollars": 10.96,
    "paybackYears": 9.7,
    "breakEvenOffGridNights": 438,
    "horizonSavingsDollars": 2958,
    "horizonNetValueDollars": -942,
    "roiPercent": -17,
    "verdictTitle": "The value case depends on how often you use it",
    "verdictDetail": "The entered setup costs about $5,400 up front, or $4,800 after avoided replacement value. It saves about $493/year, putting simple payback at roughly 9.7 years.",
    "recommendedNextMove": "Pressure-test the campground-night assumption with the boondocking cost calculator before treating the payback as real savings.",
    "watchOuts": [
      "This only counts costs you actually avoid. If you would have boondocked without solar anyway, do not credit solar for campground nights it did not change.",
      "Generator savings assume solar really replaces those run hours. Shade, winter sun, high loads, and battery limits can move some hours back to the generator.",
      "This is ownership math, not an electrical design. Confirm solar sizing, battery reserve, inverter loads, roof fit, wiring, fusing, and charge-controller limits separately."
    ]
  }
}