AC vs DC charging: which station should you choose for your EV?

AC and DC current: how they work and their impact on charging

To choose the right charging station, it’s essential to understand the specific characteristics of AC and DC charging and how they affect the charging process of your electric vehicle.

Alternating Current (AC)

Alternating Current (AC) is the type of electricity supplied by both household and public power grids. It’s commonly used for home charging and at public charging stations with moderate power levels (ranging from 3.7 kW to 22 kW).

How does it work? ⚡️

1. The electricity supplied by the grid is in alternating current (AC) form.
2. An AC charging station transfers this current directly to the vehicle.
3. The vehicle’s onboard charger then converts the AC into direct current (DC) since the battery can only store DC electricity.
4. The converted energy is stored in the EV’s battery.

Advantages: ✅

• Easy installation: AC charging stations are compatible with standard household electrical networks and don’t require heavy infrastructure.
• Compatible with all electric vehicles: Virtually every EV can be charged using an AC charger.
• More affordable: AC chargers are generally cheaper to purchase and install.
• Well-suited for daily charging: Ideal for overnight charging or when the vehicle is parked for extended periods.

Disadvantages: ❌

• Longer charging time: It can take several hours to fully charge a battery.
• Limited power output: Charging speed is restricted by the vehicle’s onboard charger, typically between 3.7 kW and 22 kW.
  
  

Direct Current (DC)

Direct Current (DC) charging is primarily used at fast-charging stations, which are typically located along motorways and major roads. Examples include Ionity fast charging stations, Tesla Superchargers, and Fastned charging stations.

How does it work? ⚡️

1. The electricity supplied by the grid is in alternating current (AC) form.
2. A DC fast charging station converts AC into DC directly using a high-power converter.
3. The direct current is then delivered straight to the vehicle’s battery, bypassing the onboard charger for faster energy transfer.

Advantages:

• Ultra-fast charging: Allows you to recover around 80% of your battery range in just 20 to 40 minutes, depending on your vehicle’s charging capacity.
• Ideal for long trips: Commonly available on motorways and at major charging hubs.
• High power output: Can reach up to 350 kW at some ultra-fast charging stations.

Disadvantages: ❌

• High cost: DC charging stations are significantly more expensive to install and maintain than AC chargers.
• Limited access: DC chargers are primarily available along major roads and highways.
• Battery wear: Frequent DC fast charging can accelerate battery degradation over the long term.

↪️ Read more about fast charging for electric vehicles.

AC vs DC charging costs

AC Charging: Generally more affordable, especially for home installations where electricity is billed at residential rates. Some public AC charging stations even offer free charging, while others charge a modest fee.

DC Charging: More expensive due to the complex infrastructure and higher power output. Public fast chargers typically apply higher rates, either per minute or per kWh.

↪️ Read more about: How much does it cost to charge an electric car?

AC or DC charging: which is the best choice for your EV?

Let’s recap:

• Daily use → AC charging: More cost-effective and well-suited for home charging or using public AC stations.
• Long trips → DC charging: Ideal for minimizing downtime when charging on motorways.

💡 Key takeaway: If you regularly charge your vehicle overnight at home or at your workplace, AC charging is the best option. However, for long-distance travel, DC charging becomes essential to reduce charging time and keep your journey efficient.