How much of the home-battery optimiser's forecast loss does re-planning every few hours recover?

What it found

Reruns the rolling linear program of energy-tou-lp-tmy on PVGIS typical-year irradiance (Golden CO, Phoenix AZ, Seattle WA) but re-plans every 24, 12, 6, 3 or 1 hours from the actual state of charge, with a nowcast forecast added. For 10 kWh behind 6 kW PV, re-planning every 3–12 h adds $10–36 a year to the realistic controllers (Golden clear-sky-index forecast $725 → $754; Seattle $678 → $713; Phoenix $780 → $797) against perfect-forecast savings of $930, $881 and $853, so it closes at most 17 percentage points of the gap between the best fixed rule and the perfect forecast. Most of the loss is forecast loss, not execution loss. A three-hour nowcast does not beat the plain clear-sky index and hourly re-planning is no better than every 3 h; it adds 20–30 cycles a year and lowers life-limited break-even price. Differences under about $10 are inside the noise of three load seeds and one typical year. Not from a source: the tariff, synthetic load, battery cost and 4,000-cycle life (inherited, assumed), the nowcast time constant (3 h, swept at one site) and the sunlit threshold.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

More in Energy supply and dense energy storage

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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.