{ "reviewedAt": "2026-09-18", "findings": [ { "id": "demand", "recommendation": "Use the central 93.4 TWh end-use case as the provisional 2050 reference. Lower demand requires the stated combination of efficiency and weaker activity; keep growth additions explicit.", "sources": [ "demand-model-v1", "demand-scenario-comparison", "bfe-data-centres-2026" ], "locator": "Central/lower/higher 2050 scenario rows; displayed growth and efficiency inputs; data-centre summary.", "limitation": "No probability is assigned to the demand cases; the central value is a planning choice, not a forecast.", "status": "editorial recommendation" }, { "id": "winter", "recommendation": "Prioritise safe nuclear, finite hydro and additional winter delivery while retaining trade. Solar and vehicle services complement this supply.", "sources": [ "bfe-electricity-2025", "portfolio-2035-model" ], "locator": "BFE table 5; twelve supply cases and partitions.", "limitation": "Seasonal trade is not a measurement of essential imports; the stress results apply to their stated future mixes.", "status": "editorial recommendation" }, { "id": "hydro", "recommendation": "Support delivery of Grimsel 4, development of Grimselsee and a viable Mattmark winter-shift project for their distinct services. Compensate owners for contracted service.", "sources": [ "kwo-grimsel4-investment", "kwo-grimsel-milestones-2026", "axpo-mattmark-project", "owner-model-v1" ], "locator": "Project records and dates in visual-chapters hydro rows; owner water/opportunity-cost calculations.", "limitation": "Conditional project preference, not final permitting or a benefit-cost ranking. Stored energy, seasonal shift and power cannot be added as one energy quantity.", "status": "editorial recommendation" }, { "id": "storage", "recommendation": "Use batteries for short-duration contracted services. Introduce smart charging before relying on bidirectional exports. Keep bulk seasonal lithium-battery storage outside the base plan.", "sources": [ "cost-chapter-calculations", "owner-model-v1", "v2x-suisse-2024", "portfolio-2035-model" ], "locator": "Battery cycling sensitivities; owner costs and trading benchmark; V2X report pages 3–5; matched vehicle cases.", "limitation": "The cycling example is hypothetical; rare reserve availability can still have value. No claim that every short-duration battery project is profitable.", "status": "editorial recommendation" }, { "id": "nuclear", "recommendation": "Pursue Gösgen/Leibstadt extension and owner-led development of a first large reference-based reactor. Use 2047 as the provisional schedule reference, with a 2053-or-later fallback.", "sources": [ "bfe-lto-2026-background", "nuclear-delivery-calculations", "historical-nuclear-selection" ], "locator": "Extension summary; delivery planning and delayed cases; historical site dossiers.", "limitation": "Editorial planning choice among illustrative schedules. No assigned probability, supplier commitment, present build permission or assured fleet build rate.", "status": "editorial recommendation" }, { "id": "beznau", "recommendation": "Base the earlier supply programme on the announced 2032/2033 retirements. Reconsider further operation only if the owner presents a funded, safe alternative.", "sources": [ "beznau-ensi-operating-horizon", "beznau-axpo-decision-faq", "nuclear-delivery-calculations" ], "locator": "ENSI licence horizon; Axpo beyond-2033 assessment; historical output.", "limitation": "No legal expiry is inferred. Owner intentions and safety findings can change; the replacement programme continues independently.", "status": "editorial recommendation" }, { "id": "costs", "recommendation": "Prioritise viable existing-reactor extensions; pay hydro and reserve providers for defined services; obtain complete new-nuclear offers with bounded risk allocation.", "sources": [ "bfe-lto-2026-background", "cost-chapter-calculations", "owner-model-v1" ], "locator": "Extension cases; cost ledger and comparison contract; owner economics.", "limitation": "A recommendation supported by bounded evidence; neither national total cost nor a household tariff has been established.", "status": "editorial recommendation" }, { "id": "2035", "recommendation": "Choose the 26 GWp solar and remaining-reactor package for development. Seek extra supply options against the 2.6 TWh winter/2.3 GW fixed-charging stress screen, and retain the conditional V2G comparison.", "sources": [ "portfolio-2035-model" ], "locator": "2012-fixed and 2022-fixed; previous plan-procurement claims use V2G cases separately.", "limitation": "Preliminary supply-offer brief from two fixed-charging weather cases (2011/12 and 2021/22), 2035 demand, up to 2 GW imports and a 90-winter-day Leibstadt outage of unestimated frequency. Perfect foresight, pooled hydro, no internal grid or probabilistic reserve margin. Not routine annual replacement energy, a final procurement volume or a guarantee of adequacy. No fixed-charging 2023/24 result is available in this edition.", "status": "editorial recommendation" }, { "id": "strategy", "recommendation": "Develop the earlier supply bridge and the new-nuclear programme together. Aim for annual net exports and resilience to restricted imports through commercially viable investments.", "sources": [ "nuclear-delivery-calculations", "portfolio-2035-model", "owner-model-v1", "bfe-monitoring-2025" ], "locator": "Programme schedules, import sensitivities, owner economics and monitoring targets.", "limitation": "The package is a proposed direction with quantified partial tests, not a completed least-cost or sovereign 2050 portfolio.", "status": "editorial recommendation" } ], "claims": [ { "id": "plan-fixed-screen-energy", "label": "2035 starting energy requirement before contracted vehicle flexibility", "value": 2.6, "unit": "TWh", "status": "scenario", "period": "2035 demand with 2011/12 and 2021/22 weather", "definition": "Maximum remaining winter energy among the two archived fixed-charging stress cases, rounded upward to 0.1 TWh.", "formula": "ceil(max(2555.6857744809754, 2258.7349184467917) / 100) / 10", "limitation": "Preliminary supply-offer brief from two fixed-charging weather cases (2011/12 and 2021/22), 2035 demand, up to 2 GW imports and a 90-winter-day Leibstadt outage of unestimated frequency. Perfect foresight, pooled hydro, no internal grid or probabilistic reserve margin. Not routine annual replacement energy, a final procurement volume or a guarantee of adequacy. No fixed-charging 2023/24 result is available in this edition.", "sources": [ "portfolio-2035-model", "supply-path-review" ], "reviewedAt": "2026-09-18" }, { "id": "plan-fixed-screen-power", "label": "2035 starting power requirement before contracted vehicle flexibility", "value": 2.3, "unit": "GW", "status": "scenario", "period": "2035 demand with 2011/12 and 2021/22 weather", "definition": "Maximum remaining hourly power gap among the two archived fixed-charging stress cases, rounded upward to 0.1 GW.", "formula": "ceil(max(2.28209526160838, 0.7046165785531138) * 10) / 10", "limitation": "Preliminary supply-offer brief from two fixed-charging weather cases (2011/12 and 2021/22), 2035 demand, up to 2 GW imports and a 90-winter-day Leibstadt outage of unestimated frequency. Perfect foresight, pooled hydro, no internal grid or probabilistic reserve margin. Not routine annual replacement energy, a final procurement volume or a guarantee of adequacy. No fixed-charging 2023/24 result is available in this edition.", "sources": [ "portfolio-2035-model", "supply-path-review" ], "reviewedAt": "2026-09-18" }, { "id": "demand-central-increase-2050", "label": "Electricity demand increase in the central 2050 case", "value": 35.85364180546513, "unit": "TWh/year", "status": "scenario", "period": "2024 observed baseline to conditional 2050 central case", "definition": "Additional annual end-use electricity, before grid losses, storage charging and net exports.", "formula": "93.36564180546513 − 57.512 = 35.85364180546513 TWh/year.", "limitation": "Inherits the central model assumptions. Additional data-centre, hydrogen, e-fuel and district-heat growth beyond sector assumptions is zero; aviation conversion is excluded. Not a forecast or generation-capacity requirement.", "sources": [ "demand-model-v1", "supply-path-review" ], "reviewedAt": "2026-09-18" }, { "id": "plan-fixed-2022-summer", "label": "Additional summer electricity in the 2021/22 fixed-charging test", "value": 47.46106856163806, "unit": "GWh", "status": "scenario", "period": "April–September portion of the 2021/22 weather case, 2035 demand", "definition": "Remaining annual electricity gap less its October–March winter portion.", "formula": "2306.1959870084297 − 2258.7349184467917 = 47.461068561638 GWh.", "limitation": "Preliminary supply-offer brief from two fixed-charging weather cases (2011/12 and 2021/22), 2035 demand, up to 2 GW imports and a 90-winter-day Leibstadt outage of unestimated frequency. Perfect foresight, pooled hydro, no internal grid or probabilistic reserve margin. Not routine annual replacement energy, a final procurement volume or a guarantee of adequacy. No fixed-charging 2023/24 result is available in this edition. This summer gap is outside the 2.6 TWh winter quantity.", "sources": [ "portfolio-2035-model", "supply-path-review" ], "reviewedAt": "2026-09-18" } ], "fixed_case_ids": [ "2012-fixed", "2022-fixed" ], "fixed_case_values": [ { "id": "2012-fixed", "winter_shortfall_gwh": 2555.6857744809754, "unserved_peak_gw": 2.28209526160838 }, { "id": "2022-fixed", "winter_shortfall_gwh": 2258.7349184467917, "unserved_peak_gw": 0.7046165785531138 } ], "inputs": [ { "path": "data/portfolio-2035-2026-09-18/case-index.json", "sha256": "3cb40592b6d3146cd1b990a4324dd3af30d61387154c90523e2edd23656b096d", "bytes": 57014 }, { "path": "data/website-demand-comparison-2026-09-17/comparison.json", "sha256": "2343c4c5f50c2963c2f6a3ad011afe78f6538acd5ae9eb0fed96eec7cc43e572", "bytes": 32788 }, { "path": "data/website-nuclear-delivery-2026-09-17/evidence.json", "sha256": "47b72acd4b7fe44677db02a3331aeb7005f07eec9a7083da32a8f6f999869ce6", "bytes": 22215 }, { "path": "data/website-visual-chapters-2026-09-17/visuals.json", "sha256": "ae1d245b371a2b5269c35136937a9727f5fe97bf28a47453ec34a71a033ee8cf", "bytes": 4857 } ] }