AC & DC, how big is the difference?

What are the differences between AC and DC charging?

AC and DC charging refer to the type of power delivered to the electric vehicle’s battery. AC charging uses alternating current, while DC charging provides direct current. The main differences come down to charging power, charge times, available locations, the charging equipment itself, and cost. AC is slower and cheaper, while DC is much faster but far less common and more expensive. Understanding your options is key.

Why does charging power differ between AC and DC?

AC EV chargers typically provide power between 3.3kW up to 22kW. This allows level 1 and level 2 public and home AC charging. But DC fast chargers can deliver 50kW to 350kW to enable rapid charging. The high-power DC current flows directly into the battery to enable this speed. Lower power AC must be converted onboard to charge the battery. So AC charges slower over longer sessions, while DC provides a quicker burst of power.

How much faster is DC fast charging?

Properly equipped EVs can add over 180 miles of range in just 15 minutes using a DC fast charger. That same amount of range could take over 3 hours using a typical home AC level 2 charger. DC charging can take an EV battery from 20% to 80% in under an hour in many cases. So DC offers vastly quicker charging times by providing more direct power faster. Just note DC chargers are still far less common than standard AC options.

Where are each type of charger located?

AC chargers are widely available. They can be found at homes, workplaces, hotels, parking garages, shopping centers, and similar everyday locations. DC fast chargers have a more limited footprint at present along major highways and travel corridors. But DC networks are expanding to make long-distance EV travel easier through fast charging pit stops. Home and workplace AC chargers still meet most daily charging needs.

What factors differ between the charging equipment?

The charging equipment itself also varies greatly. AC charging stations use simpler outlets and cables that deliver lower power for slower charging times. DC fast chargers have expensive high-voltage systems more like a commercial gas pump. DC stations tap into three-phase high-capacity power to deliver fast charging rates. Both can authorize and bill users. But DC stations come with a substantially higher price tag to purchase and install.

How much more does DC fast charging cost?

Home AC EV chargers meet most needs for just $500-$1500 plus installation. But a DC fast charging station can cost $50,000 to $100,000+ before factoring in operational expenses and electricity demands. There are alsobattery degradation concerns with excessive DC fast charging. So AC remains the affordable mainstream option, while DC fills a niche for enabling long trips via fast charging pit stops every 1-2 driving hours.

What standards are involved?

AC charging mainly uses J1772 and Type 2 connectors in North America and Europe respectively to handle 1 or 3-phase power. The unified CCS standard now combines AC and DC charging in many regions using special DC pins. Tesla uses its own proprietary AC and DC connector as well. Global confusion over plugs and charge rates remains an issue that standards seek to address.

How is charging controlled and paid for?

AC charging stations usually have an embedded cable that communicates charging details through the J1772 or Type 2 plug to bill users. DC fast chargers have more complex systems with separate credit card payment or account linking. Smart meters monitor session details. Apps and RFID key fobs help manage account access and billing. But user experience varies greatly across proprietary networks.

Do EVs require special onboard equipment?

All new EVs come equipped for AC charging via an included charge cable. DC fast charging requires dual voltage systems, liquid-cooled charge ports, and other special equipment standard in most new models. Retrofitting older EVs for DC can prove challenging however. So automakers are including improved DC charge equipment to maximize charging speeds as network availability increases.

What does the future hold?

Home and workplace AC charging will remain the most common sources used daily. But new funding aims to boost DC fast charging stations by 500% across major travel routes in coming years. This EV infrastructure build-out seeks to address range anxiety. Faster charging times via 800V systems could also allow more DC power in smaller footprints. Prioritizing user experience can help unify this complex charging landscape going forward.

Frequently Asked Questions

How do AC and DC differ for EV charging?

AC provides slower charging over longer times, while DC offers faster charging in condensed bursts.

Is AC charging still used for EVs?

Yes, AC charging at homes and workplaces meets most daily charging needs.

Where are DC fast chargers located?

Along highways and key travel corridors for long distance trips.

Does DC charging damage EV batteries?

Excessive fast charging can degrade battery health over time.

What connectors are used?

J1772 and CCS standards for AC. CCS and Tesla for DC in North America. Type 2 connectors in Europe.