For electric vehicle owners, a common question is whether investing in a higher-speed DC charger for the home is necessary or if a slower, affordable AC charger is adequate for overnight charging.
Slower Level 1 and Level 2 AC chargers take longer but cost much less than fast DC units. This article will provide a detailed analysis of normal EV charging needs and whether slow AC chargers can fully replenish an EV battery overnight.
Overnight Charging Importance in Slow AC Charger
The key benefits of overnight home charging are:
- The convenience of starting each day with a full battery
- Avoiding frequent public charging trips
- Charging during off-peak electricity hours for lower rates
- Keeping EV ready for daily commute and errands
For most urban users, the overnight charging window at home spans 6-8 hours while they sleep. This time, it should sufficiently recharge an EV battery using the appropriate charger type.
Charging Level Differences
There are three main levels of EV chargers:
Level 1 AC – Low power home and commercial AC charging
- 220V single-phase input
- Delivers 2.4-3.3 kW of power
- 6-8 hours for full charge
Level 2 AC – High power home and commercial AC charging
- 220V/415V three-phase input
- Delivers 7-22 kW of power
- 4-6 hours for full charge
DC Fast Charging – Ultra high-power commercial DC charging
- 415V three-phase input
- Delivers 50-350 kW of power
- 10-30 mins for 50-80% recharge
EV Battery Sizes in India
The typical battery pack capacity in popular EV models in India ranges between:
Hatchbacks/Sedans: 25 kWh to 40 kWh
Premium EVs/SUVs: 40 kWh to 80 kWh
Electric Two-Wheelers: 2 kWh to 4 kWh
Matching charger power output to battery size is vital for reasonable recharge times.
Estimated Home Charging Times
Here are estimated full charge times for varying battery sizes using different home charger types and power levels:
|Battery Size||Level 1 AC||Level 2 AC|
|10 kWh||4 hours||1.5 hours|
|25 kWh||10 hours||4 hours|
|40 kWh||16 hours||6 hours|
|60 kWh||24+ hours||9 hours|
|80 kWh||24+ hours||12 hours|
Level 2 AC charging offers full overnight recharge for most urban EV users in India.
Adequacy of Slow AC Charging
An affordable Level 1 or Level 2 AC charger is likely adequate for overnight home charging needs for the following situations:
- Drivers with regular daily commutes within 50 km
- Households with 8-10 hours for overnight charging
- Single EV in the home currently, not 3-4 EVs per home
- Weekend long-distance trips are not too frequent
- Public DC fast charging is available as backup nearby
- Parking space available for Level 2 charger installation
For such use cases, slow AC charging works reliably for daily drives.
Limitations of Slow AC Charging
However, there are scenarios where Level 1 and Level 2 AC charging has limitations:
- Multiple EVs per home need charging simultaneously
- Very frequent long-distance trips where fast top-ups are needed
- Homes with space constraints unable to install Level 2 chargers
- Areas prone to power outages disrupting overnight charging
- EV batteries above 60 kWh take too long to charge fully
- Urgent top-ups are needed if the assigned public charger is occupied
For such situations, having DC fast charging access is advisable.
Comparative Charging Costs in India
Charging costs vary based on type and electricity rates:
|Charger Type||Charging Cost|
|Level 1 AC||₹2-3 per hour|
|Level 2 AC||₹6-12 per hour|
|DC Fast||₹14-18 per 15 min|
Level 2 AC offers the best balance of speed and affordability for daily home charging.
Government Subsidies for Home Chargers
Under the FAME-II scheme, buyers of approved home EV chargers can avail of subsidies:
- Level 2 AC: Up to ₹3,000
- DC Fast: Up to ₹27,000 based on capacity
Subsidies make purchasing suitable home chargers more affordable.
Future Proofing for Faster Charging
If investing in a Level 2 AC charger currently, the following can future-proof homes for upgrading:
- Installing higher-capacity electrical wiring
- Upgrading breaker box with extra slots
- Leaving space for additional EVSE units
- Using modular chargers, which are hardware upgradeable
- Choosing charger brands that enable over-the-air software upgrades
This allows cost-effective upgrades to DC fast charging when needed later.
In summary, the key aspects to evaluate are:
- A Level 2 AC charger with 6-8 hour overnight charging suffices for a single EV with a daily commute within 100 km.
- DC fast charging at home is advisable for multiple EVs, long-distance driving, urgent top-ups, and large batteries.
- Carefully assess your electrical capacity, charging space, and usage needs.
- Utilize available government subsidies on approved home EV chargers.
- Plan for wiring and electrical upgrades to enable future fast charging.
For most urban apartment users, Level 2 AC delivers adequate overnight charging with prudent planning.