{
  "lastUpdated": "2026-10-20",
  "nextReviewDue": "2026-12-31",
  "notes": "Edit this file each quarter (Ofgem cap changes 1 Jan, 1 Apr, 1 Jul, 1 Oct). Values marked estimate:true are editorial assumptions, not published figures.",
  "priceCap": {
    "period": "1 October to 31 December 2026",
    "electricityUnitP": 26.32,
    "electricityStandingP": 54.83,
    "gasUnitP": 7.97,
    "gasStandingP": 29.68,
    "vatNote": "Gas includes 5% VAT. No VAT on electricity 1 Oct 2026 to 31 Mar 2027.",
    "source": "https://www.ofgem.gov.uk/information-consumers/energy-advice-households/energy-price-cap-unit-rates-and-standing-charges"
  },
  "tariffs": [
    {
      "id": "cap",
      "name": "Standard variable (price cap average)",
      "peakP": 26.32,
      "offPeakP": 26.32,
      "offPeakHours": 0,
      "standingP": 54.83,
      "source": "https://www.ofgem.gov.uk/information-consumers/energy-advice-households/energy-price-cap-unit-rates-and-standing-charges"
    },
    {
      "id": "e7",
      "name": "Economy 7 (typical, estimate)",
      "peakP": 32.0,
      "offPeakP": 15.0,
      "offPeakHours": 7,
      "standingP": 54.83,
      "estimate": true,
      "source": "https://www.ofgem.gov.uk/your-energy-supply/your-energy-bill/energy-price-cap-unit-rates-and-standing-charges"
    },
    {
      "id": "go",
      "name": "Octopus Go (EV, 4h off-peak; day rate estimate)",
      "peakP": 26.5,
      "offPeakP": 8.21,
      "offPeakHours": 4,
      "standingP": 54.83,
      "estimate": true,
      "source": "https://www.energy-review.co.uk/tariffs/octopus/price-changes"
    },
    {
      "id": "cosy",
      "name": "Cosy Octopus (heat pump, blended estimate)",
      "peakP": 40.03,
      "offPeakP": 14.0,
      "offPeakHours": 8,
      "standingP": 54.83,
      "estimate": true,
      "source": "https://www.energy-review.co.uk/tariffs/octopus/price-changes"
    }
  ],
  "exportTariffs": [
    {
      "name": "Statutory-minimum style SEG (e.g. British Gas Export SEG)",
      "p": 3.0,
      "source": "https://solarbatterygrants.co.uk/seg-rates-compared/"
    },
    {
      "name": "Octopus SEG (fixed)",
      "p": 4.1,
      "source": "https://octopus.energy/smart/smart-export-guarantee/"
    },
    {
      "name": "Outgoing Octopus (variable, Octopus import needed)",
      "p": 12.0,
      "source": "https://octopus.energy/smart/outgoing/"
    },
    {
      "name": "EDF Export Exclusive 12m (fixed)",
      "p": 18.0,
      "source": "https://solarbatterygrants.co.uk/seg-rates-compared/"
    }
  ],
  "solarYieldKwhPerKwp": {
    "_note": "Approximate annual yield for a south-facing ~35 degree roof, rounded from PVGIS and MCS irradiance zone data. Estimate.",
    "estimate": true,
    "source": "https://re.jrc.ec.europa.eu/pvg_tools/en/",
    "regions": {
      "South West England": 1000,
      "South East & London": 960,
      "East of England": 940,
      "Wales": 920,
      "Midlands": 900,
      "North West England": 860,
      "North East & Yorkshire": 850,
      "Northern Ireland": 830,
      "Scotland (south)": 820,
      "Scotland (north)": 760
    }
  },
  "orientationFactor": {
    "South": 1.0,
    "South-east / South-west": 0.95,
    "East / West": 0.82,
    "North-east / North-west": 0.65
  },
  "costs": {
    "_note": "Typical installed prices, editorial estimates. Check quotes. 0% VAT on domestic solar, batteries and heat pumps in Great Britain until 31 Mar 2027.",
    "estimate": true,
    "solarPerKwpGBP": 1500,
    "solarFixedGBP": 1000,
    "batteryPerKwhGBP": 450,
    "batteryFixedGBP": 1200,
    "ashpInstalledGBP": 12500,
    "vatSource": "https://www.gov.uk/guidance/vat-on-energy-saving-materials-and-heating-equipment-notice-7086"
  },
  "heatPump": {
    "defaultScop": 3.0,
    "boilerEfficiency": 0.88,
    "typicalGasKwh": 9500,
    "typicalElecKwh": 2500,
    "source": "https://www.ofgem.gov.uk/sites/default/files/2026-05/Review%20of%20typical%20domestic%20consumption%20values%20decision.pdf",
    "sourceNote": "Ofgem medium TDCVs from 1 July 2026 (previously 11,500 gas / 2,700 electricity)"
  },
  "bus": {
    "ashpGBP": 7500,
    "gshpGBP": 7500,
    "airToAirGBP": 2500,
    "biomassGBP": 5000,
    "offGasOilLpgBonusGBP": 1500,
    "bonusUntil": "March 2027",
    "nations": [
      "England",
      "Wales"
    ],
    "source": "https://www.gov.uk/apply-boiler-upgrade-scheme/what-you-can-get",
    "eligibilitySource": "https://www.gov.uk/apply-boiler-upgrade-scheme/check-if-youre-eligible"
  },
  "ev": {
    "defaultMilesPerKwh": 3.5,
    "chargingLoss": 0.1,
    "petrolPencePerLitre": 135,
    "petrolEstimate": true,
    "petrolSource": "https://www.gov.uk/government/statistics/weekly-road-fuel-prices"
  }
}