Solar Surplus Heater Control
Turns high-power appliances (water heater, pool pump, floor heating, etc.) on and
off in real time to consume excess solar energy instead of exporting it.
One automation per device. Devices are chained by priority — each one turns on
only after the higher-priority device has been running for 40 s, and turns off when
the lower-priority device hasn't reacted fast enough. No grid draw — devices only
run when your panels already cover them.
Key features
- Signed or absolute grid power sensor (with optional flow direction entity)
- Zero feed-in mode (inverter never exports)
- Pre-flight headroom check before turning on
- Anti-flapping hysteresis band
- Configurable solar window (elevation + azimuth) to handle panel shade
- Priority cascade: unlimited chain of devices, automatic top-down turn-on / bottom-up turn-off
- 5-minute periodic safety check
Import
Open your Home Assistant instance → Settings → Automations → Blueprints → Import Blueprint and paste this URL:
https://raw.githubusercontent.com/oticat/ha-blueprints/refs/heads/main/solar_surplus_heater.yaml
Threshold guidance
| Mode | Suggested threshold |
|---|---|
| Zero feed-in | 50 W |
| Feed-in enabled | −(device_max_watts / 2), e.g. −500 W for a 1 kW heater |
Priority chain example (3 devices)
| Device | Higher-priority switch | Lower-priority switch |
|---|---|---|
| Boiler (P1) | (empty) | switch.pool_pump |
| Pool pump (P2) | switch.boiler | switch.floor_heating |
| Floor heating (P3) | switch.pool_pump | (empty) |