{
  "slug": "solar-savings",
  "title": "Solar Savings Calculator",
  "heading": "Home Solar Savings Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/solar-savings",
  "summary": "System size, annual production, payback, and 25-year savings.",
  "description": "Payback depends on three things: your utility rate, sun hours, and the 30% federal tax credit. In high-rate states the break-even often lands under eight years.",
  "formula": "Production = kW × sun hours × 365 × 0.8 derate; payback = net cost ÷ annual savings.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=solar-savings",
  "inputs": [
    {
      "id": "usage",
      "label": "Monthly electricity use",
      "kind": "number",
      "hint": null,
      "default": 950,
      "unit": "kWh",
      "min": 100,
      "max": null
    },
    {
      "id": "rate",
      "label": "Electricity rate",
      "kind": "number",
      "hint": null,
      "default": 0.19,
      "unit": "$/kWh",
      "min": 0.05,
      "max": 1
    },
    {
      "id": "sunHours",
      "label": "Peak sun hours per day",
      "kind": "number",
      "hint": null,
      "default": 4.8,
      "unit": null,
      "min": 2,
      "max": 7
    },
    {
      "id": "costPerWatt",
      "label": "Installed cost",
      "kind": "number",
      "hint": null,
      "default": 3,
      "unit": "$/W",
      "min": 1,
      "max": 6
    },
    {
      "id": "credit",
      "label": "Tax credit",
      "kind": "number",
      "hint": null,
      "default": 30,
      "unit": "%",
      "min": 0,
      "max": 50
    },
    {
      "id": "offset",
      "label": "Target offset of usage",
      "kind": "number",
      "hint": null,
      "default": 100,
      "unit": "%",
      "min": 20,
      "max": 130
    },
    {
      "id": "escalator",
      "label": "Annual utility rate increase",
      "kind": "number",
      "hint": null,
      "default": 3,
      "unit": "%",
      "min": 0,
      "max": 10
    }
  ],
  "outputs": [
    {
      "id": "kw",
      "label": "System size (kW)",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "net",
      "label": "Net cost after tax credit",
      "format": "currency",
      "hint": null,
      "primary": false
    },
    {
      "id": "payback",
      "label": "Payback period (years)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "year1",
      "label": "First-year savings",
      "format": "currency",
      "hint": null,
      "primary": false
    },
    {
      "id": "lifetime",
      "label": "25-year net savings",
      "format": "currency",
      "hint": null,
      "primary": false
    },
    {
      "id": "panels",
      "label": "Approx. 400 W panels needed",
      "format": "number",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Monthly electricity use: 950 kWh",
      "Electricity rate: 0.19 $/kWh",
      "Peak sun hours per day: 4.8",
      "Installed cost: 3 $/W",
      "Tax credit: 30 %",
      "Target offset of usage: 100 %",
      "Annual utility rate increase: 3 %"
    ],
    "outputs": [
      "System size (kW): 8.13",
      "Net cost after tax credit: $17,080.48",
      "Payback period (years): 7.9",
      "First-year savings: $2,166.00",
      "25-year net savings: $56,761.67",
      "Approx. 400 W panels needed: 21"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter monthly electricity use (kWh).",
      "Enter electricity rate ($/kWh).",
      "Enter peak sun hours per day.",
      "Enter installed cost ($/W).",
      "Enter tax credit (%).",
      "Enter target offset of usage (%).",
      "Enter annual utility rate increase (%).",
      "Read your system size (kw) 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": {
        "usage": 550,
        "rate": 0.19,
        "sunHours": 2.88,
        "costPerWatt": 1.7999999999999998,
        "credit": 18,
        "offset": 60,
        "escalator": 1.7999999999999998
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "usage": 950,
        "rate": 0.19,
        "sunHours": 4.8,
        "costPerWatt": 3,
        "credit": 30,
        "offset": 100,
        "escalator": 3
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "usage": 1500,
        "rate": 0.19,
        "sunHours": 7,
        "costPerWatt": 4.800000000000001,
        "credit": 48,
        "offset": 130,
        "escalator": 4.800000000000001
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "How does the home solar savings calculator work?",
      "a": "Payback depends on three things: your utility rate, sun hours, and the 30% federal tax credit. In high-rate states the break-even often lands under eight years. The underlying maths is: Production = kW × sun hours × 365 × 0.8 derate; payback = net cost ÷ annual savings."
    },
    {
      "q": "What do I need to enter?",
      "a": "7 values: monthly electricity use, electricity rate, peak sun hours per day, installed cost, tax credit, target offset of usage, and annual utility rate increase. Each field starts with a sensible default, so you can change one number at a time and watch the result move."
    },
    {
      "q": "What does the system size (kw) result mean?",
      "a": "It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds."
    },
    {
      "q": "Is this calculator free, and do I need an account?",
      "a": "Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser."
    },
    {
      "q": "How accurate is the result?",
      "a": "It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/electricity-cost",
    "https://www.revenuelab.fyi/toolbox/ev-charging-cost",
    "https://www.revenuelab.fyi/toolbox/hvac-run-cost"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Solar Savings Calculator (https://www.revenuelab.fyi/toolbox/solar-savings)"
}