{
    "name": "Biogas Output Calculator",
    "url": "https://calculators.geekmidst.com/calculators/biogas-output-calculator",
    "markdown": "https://calculators.geekmidst.com/calculators/biogas-output-calculator.md",
    "category": "Energy & environment",
    "description": "Estimate daily biogas, methane, energy and electricity from an anaerobic digester’s feedstock, solids content and specific biogas yield per kg of volatile solids.",
    "summary": "Biogas comes from the volatile solids (the organic part) of the feedstock. Volatile solids × specific yield gives biogas; its methane share sets the energy content.",
    "also_called": [
        "Biogas yield calculator",
        "Anaerobic digestion calculator"
    ],
    "applies_to": "Worldwide",
    "last_updated": "2026-10-29",
    "computation": "Results are computed in the visitor’s browser on the HTML page. This API describes the calculator; it does not compute results.",
    "inputs": [
        {
            "name": "feed",
            "label": "Fresh feedstock per day",
            "type": "number",
            "default": "10",
            "unit": "t"
        },
        {
            "name": "ts",
            "label": "Total solids",
            "type": "number",
            "default": "10",
            "unit": "% of fresh mass"
        },
        {
            "name": "vs",
            "label": "Volatile solids",
            "type": "number",
            "default": "80",
            "unit": "% of total solids"
        },
        {
            "name": "yield",
            "label": "Specific biogas yield",
            "type": "number",
            "default": "0.4",
            "unit": "m³ per kg VS"
        },
        {
            "name": "ch4",
            "label": "Methane content of the biogas",
            "type": "number",
            "default": "60",
            "unit": "%"
        },
        {
            "name": "chp_eff",
            "label": "Electrical efficiency of the engine (CHP)",
            "type": "number",
            "default": "35",
            "unit": "%"
        },
        {
            "name": "days",
            "label": "Operating days per year",
            "type": "number",
            "default": "365"
        }
    ],
    "outputs": [
        {
            "key": "biogas_m3",
            "label": "Biogas per day",
            "format": "number"
        },
        {
            "key": "vs_kg",
            "label": "Volatile solids fed per day",
            "format": "number"
        },
        {
            "key": "methane_m3",
            "label": "Methane per day",
            "format": "number"
        },
        {
            "key": "energy_kwh",
            "label": "Fuel energy per day",
            "format": "number"
        },
        {
            "key": "electricity_kwh",
            "label": "Electricity per day",
            "format": "number"
        },
        {
            "key": "annual_mwh",
            "label": "Electricity per year",
            "format": "number"
        }
    ],
    "formula": {
        "text": "VS (kg) = Feed (t) × 1000 × TS% × VS%;  Biogas = VS × Yield;  CH₄ = Biogas × CH₄%;  Energy (kWh) = CH₄ × 35.8 ÷ 3.6;  Electricity = Energy × Efficiency",
        "variables": {
            "TS": "dry matter share of the fresh feedstock",
            "VS": "organic (combustible) share of the dry matter",
            "Yield": "m³ of biogas per kg VS added",
            "35.8 MJ/m³": "approximate lower heating value of methane at 0 °C and 1 atm"
        }
    },
    "worked_example": {
        "inputs": {
            "feed": "10",
            "ts": "10",
            "vs": "80",
            "yield": "0.4",
            "ch4": "60",
            "chp_eff": "35",
            "days": "365"
        },
        "steps": [
            "Volatile solids: 10 t × 1000 × 10% × 80% = 800 kg a day.",
            "Biogas: 800 × 0.4 = 320 m³; methane 320 × 60% = 192 m³.",
            "Energy: 192 × 35.8 ÷ 3.6 = 1,909.3 kWh; electricity at 35% = 668.3 kWh a day."
        ],
        "result": "10 t a day of this feedstock yields about 320 m³ of biogas, enough for roughly 670 kWh of electricity a day."
    },
    "interpretation": "The specific yield dominates the answer and depends on feedstock, temperature and retention time. Use measured or laboratory biochemical methane potential (BMP) data before sizing equipment.",
    "assumptions": [
        "Steady feeding and stable digestion.",
        "Gas volumes at normal conditions (0 °C, 1 atm)."
    ],
    "limitations": [
        "Parasitic load of the plant, flaring and heat use are not deducted."
    ],
    "rules": null,
    "faqs": [
        {
            "question": "How much energy is in a cubic metre of biogas?",
            "answer": "About 35.8 MJ (≈ 9.9 kWh) per m³ of methane, so biogas at 60% methane holds roughly 6 kWh per m³."
        },
        {
            "question": "What are total and volatile solids?",
            "answer": "Total solids is the dry matter left after drying; volatile solids is the part of it that burns off at high temperature, roughly the organic matter microbes can digest."
        }
    ],
    "sources": [],
    "related": [
        {
            "name": "Electricity Emissions Intensity Calculator",
            "url": "https://calculators.geekmidst.com/calculators/electricity-emissions-intensity-calculator"
        },
        {
            "name": "Waste Diversion Rate Calculator",
            "url": "https://calculators.geekmidst.com/calculators/waste-diversion-rate-calculator"
        },
        {
            "name": "Percentage Calculator",
            "url": "https://calculators.geekmidst.com/calculators/percentage-calculator"
        }
    ],
    "disclaimer": null,
    "publisher": "GM¹X CalcVerse"
}