{
 "title": "Where heat pumps pay off",
 "built": "2026-11-05",
 "weather_window": [
  "2025-10-28",
  "2026-10-28"
 ],
 "weather_latest_day": "2026-10-28",
 "stations_swept": 2296,
 "stations": 1983,
 "dropped": {
  "not in a US state": 79,
  "under 8,000 hours of weather in the year": 227,
  "no weather in the last 60 days": 7
 },
 "zip_codes": 40942,
 "states_covered": 50,
 "lifetime_years": 10,
 "products": 772,
 "engine": "https://www.heatpushers.com/ (home model; static/perf.js), run headless on the production page by scripts/payoff/sweep.js",
 "house": {
  "sqft": 1800,
  "stories": 2,
  "shape": "average",
  "era": "1970-89",
  "bedrooms": 3,
  "thermostat_f": 70,
  "insulation": {
   "wallR": 14,
   "ceilingR": 16,
   "floorR": 6,
   "windowU": 0.55,
   "wwrPct": 15,
   "numDoors": 2,
   "ach": 0.5,
   "ceilingHeight": 9
  },
  "covers": "whole house",
  "cooling": "not counted (heating only)",
  "ducts": "furnaces: inside the heated space, reused as they are; boilers and baseboard: none, so ductless heat pumps only",
  "when_cold": "existing heat stays and takes over in the hours it is cheaper (page default)"
 },
 "fuels": {
  "gas": {
   "page_key": "gas_80",
   "label": "Gas furnace",
   "efficiency_pct": 80
  },
  "oil": {
   "page_key": "oil_boiler",
   "label": "Oil boiler",
   "efficiency_pct": 85
  },
  "propane": {
   "page_key": "propane_92",
   "label": "Propane furnace",
   "efficiency_pct": 92
  },
  "electric": {
   "page_key": "electric",
   "label": "Electric baseboard",
   "efficiency_pct": 100
  }
 },
 "install": {
  "pro_per_indoor_unit": 2500,
  "diy_tools_once": 350,
  "diy_materials_per_indoor_unit": 300,
  "diy_lineset_credit": 150
 },
 "prices": "EIA state average residential prices as served by heatpushers.com /api/degdays on the build date",
 "attribution": "HeatPushers, \"Where heat pumps pay off\", https://www.heatpushers.com/where-heat-pumps-pay-off",
 "license": "CC BY 4.0"
}