{"generated_for_reference_date":"2026-07-01","battery_defaults":{"one_way_efficiency":0.938,"round_trip_efficiency":0.8798,"round_trip_note":"What real INSTALLED systems achieve with the hybrid inverter in the loop (~85-88%). Datasheet cells look like 95%+; quoting that is how a calculator quietly gains a few percent.","standby_w":10,"standby_note":"The battery + inverter draw 10.0 W continuously = ~88 kWh/yr of pure loss, whether or not they ever cycle. We charge it to the battery case only. It is why a battery can leave you WORSE off on a low-spread day. Most calculators omit this entirely.","max_cycles_per_day":2,"degradation_cost_per_kwh":0,"degradation_note":"Deliberately 0 in the dispatch: the capital cost is accounted for in the payback calculation instead. Charging both would double-count."},"payback":{"capacity_fade_per_year":0.02,"assumed_lifetime_years":15,"method":"Cumulative savings with capacity fade until they repay the price. The naive price / first-year-savings pretends savings never decline. If it does not repay within the lifetime we say 'never' rather than quoting a meaningless 27-year 'payback'."},"dispatch":{"method":"Linear program per day (scipy HiGHS), grid-side kWh accounting.","foresight":"Perfect within-day foresight = an UPPER BOUND. Day-ahead prices genuinely are known a day ahead, so that part is realistic; your load and solar are not, so real results will be lower.","constraints":["SoC bounds via cumulative constraints; SoC returns to its start each day","power cap on charge and discharge","max cycles/day cap","no grid passthrough: export <= solar + discharge (you cannot resell grid imports)"]},"prices":{"source":"energy-charts.info (Fraunhofer ISE)","license":"CC BY 4.0","resolution":"hourly before 2025-10-01, 15-minute after","timezone":"stored in UTC; grouped into Europe/Amsterdam local days (DST-correct: 23h/25h days)","coverage":[{"zone":"DE-LU","from":"2018-10-01","to":"2026-07-09","intervals":88440,"nulls":0},{"zone":"NL","from":"2016-01-01","to":"2026-07-09","intervals":112535,"nulls":0}]},"solar":{"source":"PVGIS v5.3 (EU JRC), SARAH3 radiation","real_year_available_through":2023,"note":"For price years up to 2023 we align the ACTUAL solar year to the actual prices. Later years fall back to a typical meteorological year, because PVGIS does not have them yet. Shading, inverter clipping and panel degradation are not modelled."},"load":{"nl_default":"synthetic Dutch household profile scaled to your annual kWh","de_default":"BDEW/VDEW H0 standard load profile with the official dynamization","note":"This is the biggest per-household error source: your house is not average. Upload your own smart-meter (P1) export and we use your real metered consumption instead — it typically moves the answer by tens of percent."},"tariffs_nl":{"valid_from":"2026-01-01","energy_tax_eur_per_kwh":0.1088,"vat_rate":0.21,"net_metering_active":true,"saldering_model":"Volumetric and time-blind annual netting (that is what saldering actually is), with the surplus above consumption paid at feed-in.","providers":[{"name":"ANWB Energie","markup_eur_per_kwh_excl_vat":0.0149,"monthly_fee_eur":8.5,"terugleverkosten_eur_per_kwh":0,"confidence":{"markup":"high","monthly_fee":"high","terugleverkosten":"high"},"publish_grade":true,"verified_on":"2026-07-10"},{"name":"Budget Energie","markup_eur_per_kwh_excl_vat":0.0168,"monthly_fee_eur":5.99,"terugleverkosten_eur_per_kwh":0,"confidence":{"markup":"medium","monthly_fee":"medium","terugleverkosten":"high"},"publish_grade":true,"verified_on":"2026-07-10"},{"name":"NextEnergy","markup_eur_per_kwh_excl_vat":0.0181,"monthly_fee_eur":5.99,"terugleverkosten_eur_per_kwh":0,"confidence":{"markup":"low","monthly_fee":"high","terugleverkosten":"high"},"publish_grade":true,"verified_on":"2026-07-10"},{"name":"Tibber","markup_eur_per_kwh_excl_vat":0.015,"monthly_fee_eur":5.99,"terugleverkosten_eur_per_kwh":0.0248,"confidence":{"markup":"low","monthly_fee":"medium","terugleverkosten":"high"},"publish_grade":true,"verified_on":"2026-07-10"},{"name":"Zonneplan","markup_eur_per_kwh_excl_vat":0.0165,"monthly_fee_eur":6.25,"terugleverkosten_eur_per_kwh":-0.02,"confidence":{"markup":"high","monthly_fee":"high","terugleverkosten":"high"},"publish_grade":true,"verified_on":"2026-07-10"},{"name":"Eneco Dynamisch","markup_eur_per_kwh_excl_vat":0.0199,"monthly_fee_eur":7,"terugleverkosten_eur_per_kwh":0.0292,"confidence":{"markup":"low","monthly_fee":"medium","terugleverkosten":"medium"},"publish_grade":false,"verified_on":"2026-07-10"},{"name":"Fixed (typical 2026)","markup_eur_per_kwh_excl_vat":0,"monthly_fee_eur":5.95,"terugleverkosten_eur_per_kwh":0,"confidence":{"markup":"unknown","monthly_fee":"unknown","terugleverkosten":"unknown"},"publish_grade":false,"verified_on":"2026-07-10"},{"name":"Frank Energie","markup_eur_per_kwh_excl_vat":0.0182,"monthly_fee_eur":4.99,"terugleverkosten_eur_per_kwh":0.0182,"confidence":{"markup":"medium","monthly_fee":"low","terugleverkosten":"low"},"publish_grade":false,"verified_on":"2026-07-10"},{"name":"Vandebron","markup_eur_per_kwh_excl_vat":0.0183,"monthly_fee_eur":6.99,"terugleverkosten_eur_per_kwh":0.01361,"confidence":{"markup":"high","monthly_fee":"high","terugleverkosten":"low"},"publish_grade":false,"verified_on":"2026-07-10"}]},"tariffs_de":{"valid_from":"2026-01-01","vat_rate":0.19,"stromsteuer_eur_per_kwh":0.0205,"umlagen_eur_per_kwh":0.02946,"konzessionsabgabe_eur_per_kwh":0.0167,"eeg_feedin_ueberschuss_eur_per_kwh":0.0778,"note":"Germany has no net metering: export earns a FIXED EEG rate while self-consumption avoids the full retail price, so the asymmetry is permanent rather than a 2027 cliff. Netzentgelte and §14a modules are regional (per Netzbetreiber) — give a postcode for your real one."},"what_we_refuse_to_publish":["Any comparison built on a tariff we have not verified against the provider's own sheet — the dynamic-vs-fixed panel stays hidden until a real fixed contract is verified.","A payback number when the battery does not repay within its lifetime. We say 'never' instead."],"known_limitations":["We have never validated against a real household's measured bill. Our verdict is triangulated against independent studies (CE Delft 6.5-22yr, jeroen 10-22yr, Consumentenbond 'often not within the ~15-yr life') and a test fails if we ever drift faster than any of them.","Perfect within-day foresight on load and solar makes results an upper bound.","Typical-year solar for price years PVGIS does not cover yet; no shading or inverter clipping.","Some provider fields (notably the per-kWh markup) are not published by the providers themselves and rest on comparison sites — flagged per field.","§14a Modul 3 tiers are applied year-round, though some German operators only run time-variable pricing in winter quarters."]}