For a 10 kWh home battery in Austria, this analysis uses real day-ahead EPEX spot prices (via aWATTar) and Vienna weather (via Open-Meteo) to compare an AI-optimised charge/discharge strategy against a basic time-of-day timer. Period covered: September 26 – 2, 2026.
The optimal strategy earned €13.17 over the week versus €1.31 for the basic timer — a +908% uplift, projecting to roughly €600 per year for a single 10 kWh battery cycled once per day.
Average temperature was 17.4°C, with 56 hours of strong sunshine (solar ≥ 200 W/m²), average wind 8.7 km/h, and 0.0 mm of rainfall over the week.
Solar irradiance and spot price correlated at r=-0.75 (solar lowers prices), wind at r=-0.32 (wind lowers prices). These match what you would expect: more renewable feed-in pushes prices down, so the optimal strategy is to charge during high-renewable, low-price hours and discharge in the evening peak.
| Date | Optimal Strategy | Basic Timer | Spread | Weather |
|---|---|---|---|---|
| 2026-09-25 | €0.00 | €0.00 | 0.0 ct/kWh | 13°C · ☀ 0 W/m² · 💨 2 km/h |
| 2026-09-26 | €1.81 | €0.18 | 20.1 ct/kWh | 15°C · ☀ 579 W/m² · 💨 4 km/h |
| 2026-09-27 | €1.91 | €0.42 | 21.2 ct/kWh | 16°C · ☀ 598 W/m² · 💨 8 km/h |
| 2026-09-28 | €2.59 | €0.18 | 28.8 ct/kWh | 18°C · ☀ 617 W/m² · 💨 8 km/h |
| 2026-09-29 | €1.42 | €0.01 | 15.8 ct/kWh | 18°C · ☀ 619 W/m² · 💨 11 km/h |
| 2026-09-30 | €2.02 | €0.24 | 22.5 ct/kWh | 19°C · ☀ 613 W/m² · 💨 13 km/h |
| 2026-10-01 | €2.12 | €0.10 | 23.5 ct/kWh | 19°C · ☀ 601 W/m² · 💨 13 km/h |
| 2026-10-02 | €1.29 | €0.17 | 14.3 ct/kWh | 18°C · ☀ 567 W/m² · 💨 5 km/h |
Want this kind of analysis on your own battery fleet? Get in touch.