EV Smart Charging with Home Assistant: The Complete 2025 Guide

If you're charging your EV the moment you plug it in, you're likely overpaying by 40-50%. Smart charging with Home Assistant can automatically optimize when and how your car charges, saving hundreds of euros per year while extending battery life.

In this guide, we'll cover everything from basic price-optimized charging to advanced solar integration and the emerging vehicle-to-home (V2H) technology.

Why Smart EV Charging Matters

The math is simple. Let's say you drive 300 km per week with an EV consuming 0.2 kWh/km:

• Weekly consumption: 60 kWh
• Annual consumption: 3,120 kWh
• Peak rate charging (€0.35/kWh): €1,092/year
• Off-peak charging (€0.18/kWh): €562/year
• Annual savings: €530

And that's before considering solar integration, which can reduce costs to near-zero.

Compatible Home Chargers

The good news: most modern smart chargers work with Home Assistant. Here are the most popular options with native or community integrations:

The EV Smart Charging Integration

The EV Smart Charging custom integration for Home Assistant is a game-changer. It automatically calculates the cheapest charging windows based on your electricity prices.

Here's how it works:

1. You set your departure time and desired charge level
2. The integration fetches electricity prices (Nordpool, Tibber, Essent, etc.)
3. It calculates which 15-minute intervals give the lowest total cost
4. Charging starts and stops automatically during those windows

Solar-Integrated Charging

If you have solar panels, the real magic happens when you combine price optimization with solar excess charging. The logic:

1. Priority 1: Charge from solar excess (free energy)
2. Priority 2: Charge during cheapest grid periods
3. Priority 3: Emergency charge if battery too low for tomorrow's trip

A typical automation monitors your solar production vs. house consumption. When production exceeds consumption by more than 1.4 kW (minimum charging current for most EVs), charging begins automatically.

alias: "Solar Excess EV Charging"
trigger:
  - platform: numeric_state
    entity_id: sensor.solar_excess_power
    above: 1400
    for: "00:05:00"
action:
  - service: switch.turn_on
    target:
      entity_id: switch.ev_charger

Vehicle-to-Home (V2H): The Future is Here

In October 2025, the first mass-market vehicle-to-home demonstrations launched in California, and this technology is coming to Europe fast.

The concept: your EV battery becomes a home battery. During grid outages or expensive peak periods, power flows from your car back into your home.

Current requirements:

• A V2H-capable vehicle (Kia EV6, Hyundai Ioniq 5/6, certain Nissan models)
• A bidirectional charger (Wallbox Quasar, Dcbel r16)
• Home Assistant integration for intelligent control

While still early, V2H can provide 10-20 kWh of backup power - enough to run essential appliances for 1-2 days during an outage.

Load Balancing

If you have multiple high-power devices (heat pump, induction cooktop, dryer), you need load balancing to avoid tripping breakers or exceeding your grid connection limit.

Home Assistant can monitor total house consumption and dynamically adjust EV charging current:

• House using 8 kW of your 10 kW connection? EV charges at 2 kW
• Heat pump cycles off? EV ramps up to full power
• Someone turns on the oven? EV reduces charging current

This prevents expensive grid upgrades while maximizing charging speed when capacity is available.

Getting Started

Here's the recommended path:

1. Install your charger integration - Most take under 15 minutes
2. Add price data - Nordpool, Tibber, or your provider's integration
3. Install EV Smart Charging - From HACS
4. Configure basic automation - Set departure times and price thresholds
5. Add solar integration - If applicable, prioritize solar excess
6. Implement load balancing - Prevent grid overloads