Charge Your EV with Solar Surplus
Hanergy dynamically adjusts your EV charge rate based on available solar surplus. No grid power wasted, no manual scheduling, no forecasts needed.
The Problem
Most EV owners plug in at night and charge from the grid at full price. During the day, their solar panels produce surplus energy that gets exported back to the grid — often for a fraction of the retail rate.
Even with time-of-use tariffs, the math rarely works out. The cheapest electricity is the electricity already on the roof.
The Solution
Hanergy monitors solar surplus every 10 seconds and dynamically adjusts the EV charge rate to match. When clouds pass, the charge rate drops. When the sun returns, it ramps back up. The result: maximum solar self-consumption with zero grid import for EV charging.
How It Works
Configure the EV charger as a dynamic load
Hanergy uses the dynamic load type. The setpoint controls charge current (amps) or power (watts), and Hanergy adjusts it continuously based on available surplus.
Set a minimum threshold
Most EV chargers require a minimum of 6A (approximately 1,400W on single-phase). Hanergy only activates charging when surplus exceeds this minimum, preventing inefficient trickle charging.
Assign a priority
Place the EV charger at priority 1 to ensure it gets surplus first, or lower if other loads (like a heat pump) take precedence.
Hanergy handles the rest
Every 10 seconds, the engine recalculates available surplus, adjusts the charge rate, and logs every decision. Cloud transients are smoothed with EMA filtering to prevent rapid oscillation.
Example Configuration
EV Charger
Type: Dynamic
Priority: 1
Entity: number.wallbox_charging_current
Min power: 1,400 W (6A single-phase)
Max power: 7,400 W (32A single-phase)
Feedback: sensor.wallbox_charging_powerThis configuration places the EV charger as the highest priority load. Hanergy activates charging when at least 1,400W of surplus is available and ramps up to 7,400W as production increases.
Compatible Chargers
Hanergy works with any EV charger that has a Home Assistant integration exposing a controllable entity (switch, number, or input_number). Popular options include:
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