Does time-of-use pricing make a home battery pay, and which size?

What it found

Adds an hourly time-of-use import price to energy-home's solar-plus-battery model (10 seeded synthetic weather years, assumed three-band tariff with the same $0.296 average as a flat $0.30). A 10 kWh battery behind 6 kW of PV breaks even at $641/kWh installed with peak-only discharge and off-peak grid charging, against $444 on the flat tariff, still under the assumed $800. Only small batteries clear $800 ($856 at 2.5 kWh, $847 at 5 kWh); 15 and 20 kWh fall to $427 and $320. Half-filling from the grid ($674) beats a full fill ($641). Break-even tracks the peak price ($307, $641, $1,208 at $0.28, $0.45, $0.70). Stylised: assumed tariff, synthetic weather, fixed dispatch rule, no degradation.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
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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.