{
  "reviewedAt": "2026-09-16",
  "concepts": [
    {
      "id": "power-and-energy",
      "statement": "Power is the rate of supplying or using electricity; energy is the amount over time. Watt-hour prefixes follow the corresponding watt prefixes.",
      "sources": [
        "eia-electricity-units"
      ],
      "boundary": "Definitions, not measured appliance consumption. Unit conversions are exact."
    },
    {
      "id": "capacity-factor-not-uptime",
      "statement": "Capacity factor is actual energy divided by rated power times elapsed hours. Partial-load operation changes the result as well as outages.",
      "sources": [
        "nuclear-history-calculation"
      ],
      "boundary": "Keep net/gross definitions and rating changes consistent; not simply the fraction of hours operating."
    },
    {
      "id": "seasonal-trade",
      "statement": "The 2024/25 hydrological year had net exports while its winter had net imports. Winter 2023/24 had net exports.",
      "sources": [
        "bfe-electricity-2025",
        "primer-calculations"
      ],
      "boundary": "Physical cross-border flows. Does not establish unserved demand, unavoidable imports or hourly supply availability."
    },
    {
      "id": "winter-mix",
      "statement": "Hydro and nuclear were the two largest domestic generation categories in winter 2024/25. Solar generation was positive and lower than summer 2025 generation.",
      "sources": [
        "bfe-electricity-2025"
      ],
      "boundary": "Table 5. Hydro includes pumped output before deducting pumping input. Seasonal solar comparison includes fleet growth."
    },
    {
      "id": "storage-shifts-energy",
      "statement": "Batteries and electricity-driven pumped storage must be charged and return less electricity than the charging cycle consumes.",
      "sources": [
        "eia-electricity-storage"
      ],
      "boundary": "The statement concerns storage of electricity; natural water inflows can add energy to a mixed hydro scheme."
    },
    {
      "id": "hydro-types",
      "statement": "River hydro uses flowing water; reservoirs can retain natural inflows; pumped storage uses electricity to lift water for later generation.",
      "sources": [
        "eia-hydropower"
      ],
      "boundary": "Physical principles, not evidence that all reservoirs can exchange water or have identical commercial and environmental constraints."
    },
    {
      "id": "heat-pump-principle",
      "statement": "Electric heat pumps move heat from air, ground or water; delivered heat includes environmental energy.",
      "sources": [
        "swissenergy-heat-pumps"
      ],
      "boundary": "No fixed winter performance ratio is asserted. Performance depends on equipment and conditions."
    },
    {
      "id": "electrification-demand",
      "statement": "Replacing fuel-using equipment requires conversion efficiency and demand assumptions, not a one-for-one swap of fuel energy for electricity.",
      "sources": [
        "demand-model-v1"
      ],
      "boundary": "Future national totals are scenarios. The guide does not claim a proven 2050 demand forecast."
    },
    {
      "id": "planning-tests",
      "statement": "Compare difficult-hour supply, construction and connection dates, dependencies, owner viability and adverse cases for all portfolios.",
      "sources": [],
      "boundary": "Editorial assessment and proposed decision criteria, not a finding that one portfolio has already passed."
    }
  ]
}