{
  "slug": "truck-idle-time-cost",
  "title": "Truck Idle Time Fuel Cost Calculator",
  "heading": "Truck Idle Fuel Cost Calculator",
  "category": "financial",
  "url": "https://www.revenuelab.fyi/toolbox/truck-idle-time-cost",
  "summary": "What idling for climate control and rest actually costs per year.",
  "description": "A long-haul truck idling overnight for climate control and hotel load burns roughly 0.8-1.0 gallons per hour depending on engine size and ambient temperature, and drivers who idle 8-10 hours a night can burn through 1,500+ gallons a year just sitting still. This calculator multiplies your average idle hours per day by idle fuel burn rate and diesel price to show annual idle fuel cost, and compares it against the cost of an APU (auxiliary power unit) or bunk heater investment to show the payback period — often under two years for drivers who idle heavily.",
  "formula": "Annual idle cost = idle hours/day × 365 × gal/hr × price/gal.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=truck-idle-time-cost",
  "inputs": [
    {
      "id": "idleHoursPerDay",
      "label": "Average idle hours per day",
      "kind": "number",
      "hint": null,
      "default": 8,
      "unit": "hr/day",
      "min": 0,
      "max": null
    },
    {
      "id": "idleGph",
      "label": "Idle fuel burn rate",
      "kind": "number",
      "hint": null,
      "default": 0.85,
      "unit": "gal/hr",
      "min": 0.1,
      "max": null
    },
    {
      "id": "dieselPrice",
      "label": "Diesel price",
      "kind": "number",
      "hint": null,
      "default": 3.95,
      "unit": "$/gal",
      "min": 0,
      "max": null
    },
    {
      "id": "apuCost",
      "label": "APU/bunk heater investment",
      "kind": "number",
      "hint": null,
      "default": 8500,
      "unit": "$",
      "min": 0,
      "max": null
    },
    {
      "id": "apuFuelSavingsPct",
      "label": "Idle fuel reduction with APU",
      "kind": "number",
      "hint": null,
      "default": 80,
      "unit": "%",
      "min": 0,
      "max": 100
    }
  ],
  "outputs": [
    {
      "id": "annualCost",
      "label": "Annual idle fuel cost",
      "format": "currency",
      "hint": null,
      "primary": true
    },
    {
      "id": "annualSavings",
      "label": "Annual savings with APU/heater",
      "format": "currency",
      "hint": null,
      "primary": false
    },
    {
      "id": "paybackYears",
      "label": "APU payback period",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "annualGallons",
      "label": "Annual idle gallons burned",
      "format": "number",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Average idle hours per day: 8 hr/day",
      "Idle fuel burn rate: 0.85 gal/hr",
      "Diesel price: 3.95 $/gal",
      "APU/bunk heater investment: 8500 $",
      "Idle fuel reduction with APU: 80 %"
    ],
    "outputs": [
      "Annual idle fuel cost: $9,804",
      "Annual savings with APU/heater: $7,843",
      "APU payback period: 1.08",
      "Annual idle gallons burned: 2,482"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter average idle hours per day (hr/day).",
      "Enter idle fuel burn rate (gal/hr).",
      "Enter diesel price ($/gal).",
      "Enter apu/bunk heater investment ($).",
      "Enter idle fuel reduction with apu (%).",
      "Read your annual idle fuel cost on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "idleHoursPerDay": 4.8,
        "idleGph": 0.51,
        "dieselPrice": 2.37,
        "apuCost": 5100,
        "apuFuelSavingsPct": 50
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "idleHoursPerDay": 8,
        "idleGph": 0.85,
        "dieselPrice": 3.95,
        "apuCost": 8500,
        "apuFuelSavingsPct": 80
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "idleHoursPerDay": 12.8,
        "idleGph": 1.36,
        "dieselPrice": 6.32,
        "apuCost": 13600,
        "apuFuelSavingsPct": 100
      }
    }
  ],
  "limitations": [
    "Results are estimates before tax, fees, and inflation unless an input explicitly covers them.",
    "Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.",
    "This is educational maths, not financial advice. Check anything contractual with the lender or your accountant."
  ],
  "faq": [
    {
      "q": "How much fuel does idling really burn?",
      "a": "A typical Class 8 sleeper idles at 0.6-1.0 gallons per hour depending on engine size, block heater use, and accessory load. Over a year of nightly idling that adds up to 1,000-1,800+ gallons — often 5-8% of a long-haul truck's total annual fuel spend."
    },
    {
      "q": "Are there rules against idling?",
      "a": "Many states and some municipalities have idle-limit laws (commonly 5 minutes) with exceptions for extreme temperatures or mandatory rest periods, and truck stops increasingly meter idle time or offer paid shore-power/HVAC hookups as an alternative."
    },
    {
      "q": "Is an APU worth it for every driver?",
      "a": "It pencils out fastest for drivers who idle 6+ hours nightly in variable climates. Drivers who mostly run in mild climates or use truck stop electrification services may find the payback period too long to justify the upfront cost and added maintenance."
    },
    {
      "q": "What other options reduce idle cost besides an APU?",
      "a": "Bunk heaters (diesel-fired, cheaper than a full APU) handle heat but not AC; battery-electric APUs handle both but cost more upfront; truck stop shore power costs a nightly fee but requires no capital investment and no added maintenance."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/fuel-surcharge-recovery",
    "https://www.revenuelab.fyi/toolbox/owner-operator-cost-per-mile",
    "https://www.revenuelab.fyi/toolbox/empty-mile-fuel-cost"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Truck Idle Time Fuel Cost Calculator (https://www.revenuelab.fyi/toolbox/truck-idle-time-cost)"
}