By evcharger
Are you considering an electric vehicle but worried about the charging options? With over 3 million EVs already on the road and more drivers going electric every year, smart charging decisions are crucial.
Like any car, EVs need regular refueling to keep you on the go. But instead of pulling into gas stations, EV owners rely on home, and public charging stations to keep their EV batteries juiced up. Both options have their perks, so we have broken down the complex details into digestible pieces of information. This will help you pick the charging approach that fits your lifestyle and needs.
You’ll get insider knowledge on installation costs, charging speeds, when each makes the most sense and more. Whether you own an EV or are considering buying one, this intel will help you chart the best charging strategy. Saving time and money down the road.
Charging Basics
Before diving into the details of home versus public charging, it’s helpful to understand some EV charging basics. EV charging is divided into three levels based on the output voltage and charging speed:
Level 1 – Uses a 120V household outlet, and the maximum output is 1.3 kW to 2.4 kW, translating into 3-5 miles of range per hour of charging. Most homes already have 120V outlets, so you don’t require additional equipment.
Level 2 – Requires installation of a 240V outlet and provides 14-75 miles of range per hour of charging. The maximum power output varies between 7.4kW to 22kW. Most homes will need an electrician to install the 240V outlet.
DC Fast Charging – Uses 480V direct current to provide 173-298 miles of range in one hour of charging and supplies 50kW to 400kW power to the EV. However, these stations are expensive to install and impractical for home use.
Most EV drivers rely on a mix of Level 1 and Level 2 charging to keep their battery topped off. Public DC fast charging provides a rapid boost when needed. Now let’s explore the key differences between doing this charging at home versus public stations.
Home charging
Let’s take a brief look at the pros and cons of having access to home charging, and then we will explore the individual details:
Pros:
- Convenient charging at home each night and morning
- Low electric rates offer very affordable charging costs
- A reliable home power source avoids issues accessing stations
- The home installation gives secure, dedicated charging access
- Smart charging features like V2G and solar integration
Cons:
- Upfront installation costs for electrical upgrades
- Lack of access for renters, apartment dwellers, etc.
- The local grid may require upgrades to support added loads
- Longer charge times compared to rapid public DC charging
- Limited charging speed due to onboard vehicle charger capacity
Public charging:
Here are the pros and cons of using public charging stations:
Pros:
- Enables rapid charging for travel via widespread DC fast charging stations
- Flexibility to charge on the go as needed
- No upfront installation costs
- Provides charging access for those without home charging capabilities
- Large public investments expanding charging stations nationwide
Cons:
- Availability issues at busy stations lead to waiting times
- Reliability depends on individual station uptime and maintenance
- Higher per-session charging costs compared to home
- Public funding still leaves geographic gaps in rural areas
- Careful planning required to ensure accessible stations during long route travels
Now, let’s probe into the details.
Convenience
Home Charging:
A major advantage of home charging is the added convenience. Just plug in whenever parked at home, and wake up to a fully charged EV every morning. No need to drive to a charging station or wait in line. This also avoids “range anxiety” – the worry about running out of charge mid-trip.
Charging at home also enables the consumers to:
- Charge overnight when energy rates may be lower
- Charge during solar peak generation if solar panels are installed
- Precondition the battery while plugged in to maintain optimal temperature
However, home charging does require some infrastructure. Level 2 charging needs a high-voltage 240V outlet which may require electrical work. Those who rent or live in multi-unit dwellings may not have access to charge at home. Parking availability can also be an issue.
Public charging:
Public charging offers flexibility for those who can’t charge at home. More than 160,000 public charging ports are available in the US, with around 30,000 providing access to rapid DC fast charging for travel. Apps can locate stations and pay for charging. However, wait times at popular stations can be an issue, especially on travel routes. Finding an available charger may require planning ahead.
Winner:
Overall, home charging wins for convenience IF the infrastructure is in place. Public charging enables flexibility for those without home access.
Cost Comparison
Home Charging:
The cost difference between home and public charging is a big factor for many consumers. Home charging requires an upfront investment, while public charging has variable per-session fees.
Installing the Level 2 home charging typically costs $1200-$2500 with a professional electrician. This includes any panel upgrades, i.e., installation of 240V outlet, needed to support the added load. Homeowners may also be eligible for tax credits to offset 30% of the installation cost.
Ongoing charging expenditure is tied to electricity rates, which average around 15-17 cents per kWh nationally. Based on average EV energy use, this equates to around $600-800 in home charging costs for the typical driver per year. Costs may be lower overnight when rates can dip under 10 cents/kWh. Moreover, solar energy can also help limit daytime charging costs.
Public charging:
Public charging costs vary significantly:
- Level 2 public charging: 20-25 cents per kWh
- DC fast charging: 40-60 cents per minute of charging
Public DC fast charging rates can vary substantially between networks and regions. In Washington, D.C., Electrify America charges non-members 48 cents per kWh, with members paying a discounted 36 cents per kWh after a $4 monthly fee. For example, fully charging a 2023 Chevy Bolt (which requires 28 kWh for 100 miles of range) would cost $34.81 at the standard rate. One hour of fast charging for this vehicle averages around $28.80 based on the station’s output.
For Electrify America stations that bill per minute of charging time, Level 2 charging rates average around $0.03 (3 cents) per minute. Level 2 and DC fast charging rates are equivalent at locations that charge per kWh.
Comparatively, EVgo offers non-member pay-as-you-go DC fast charging in Washington D.C. at 35 cents per minute of charging time. Therefore, a full-hour fast-charging session would cost approximately $21.
Winner:
While public charging eliminates upfront infrastructure costs, the higher per-session rates often make home charging more affordable in the long run for regular drivers.
Home charging provides level 1 or 2 charging facilities only. Your EV will get 3-5 miles of range per hour with Level 1 home charging.
Charging Speed Comparison
Home Charging:
Home Level 2 charging at 14-75 miles of added range per hour is relatively faster and usually sufficient for typical daily charging needs. The convenience of plugging in at home each night outweighs the slower charge rate for most drivers.
Think of home Level 2 charging as the cake that gradually rises overnight in the oven. Public fast charging is the microwave that quickly warms up leftovers when you need a quick bite.
Public charging:
For those needing to maximize driving range in the shortest time, public DC fast charging is the clear winner. These stations can add 173-298 miles of range per hour and get your EV up and running as you go grab a snack. However, a few caveats to keep in mind:
- Fast charging applies the most stress to the battery and may impact long-term health if used regularly
- Home Level 2 charging is generally “fast enough” for daily commutes and routine driving
- New EVs coming to market charge even faster, some as quick as 15 minutes to add 200+ miles of range
Winner:
Fast public charging is clearly the winner for those who drive longer daily distances or have limited home charging access. But for most, Level 2 home charging delivers more than enough “cake” overnight.
Charging Technology Comparison
We’ve compared home and public charging speeds, but what about the underlying technology? There are important technical differences between Level 2 home units and fast public DC chargers.
Home Charging:
Level 1 and 2 home charging stations use the J1772 standard, which supports single-phase 220-240V connections and up to 80 amps of current. This power is sent through the onboard charger built into the EV. Most EVs have 6-11 kW onboard chargers, limiting their Level 2 charging rate accordingly despite a home unit’s higher output. Home charging technology is also advancing with smarter grid integration like V2G and solar synchronization.
- New Level 2 units like ChargePoint’s Home Flex offer up to 37 miles of range per hour by utilizing higher voltage connections. This matches some older public DC fast chargers.
- Pairing home solar power with an EV enables 100% daylight charging from clean energy. Any excess solar can also provide power back to the home.
- V2G integration allows EVs to supply power from their battery back to the grid during peak demand times. The vehicle acts like a large home battery storage system.
- Smart charging coordination optimizes home charging by scheduling sessions during off-peak grid times or maximizing solar energy.
Public charging:
Level 1 and 2 public chargers (except Tesla) also use the J1772 standard. Still, DC fast charging uses the CCS (North America) or CHAdeMO (Asia) standards to deliver direct high-voltage DC current directly to the battery at up to 500 amps. This bypasses the onboard charger and provides rapid 200+ kW charging rates. However, it requires costly high-power DC stations and compatible EV battery chemistry.
Automakers are developing next-gen EV architecture designed for ultra-fast charging up to 1000 kW, which will evolve DC fast charging capabilities.
Winner:
Not all EVs are compatible with fast charging. But every EV can use the Level 2 home charging option thanks to the standardized J1772 connection. Even Tesla owners can use aftermarket cables that will help connect their EVs to J1772 ports. DC charging technologies are relatively new, whereas home Level 2 chargers remain the most mature and widely supported charging options.
Charging Availability & Reliability
Home Charging:
Home charging always provides a convenient and reliable fallback. Charge the EV overnight and enjoy daily commuting without worrying about waking up in time and finding spots at busy charging stations. But homeowners must consider risks like power outages that can disrupt home charging capabilities. In such instances, public charging stations are always there as the backup.
Public charging:
Public EV charging ports have grown dramatically in recent years, led by investments from EVgo, ChargePoint, Electrify America, and others. However, availability remains a key concern for public charging users.
While over 161,500 public ports now exist nationally, these are not spread evenly. Charging deserts still exist in rural areas and poor urban neighborhoods. Public chargers are also frequently clustered around affluent metro areas.
Utilization rates also limit accessibility at many charging locations. Most DC fast charging ports are already utilized during peak hours. Even higher utilization is seen in California, leading to long wait times at popular stations.
Reliability is also a concern with public EV charging. Stations can suffer downtime from technical issues, network outages, vandalism, or extreme weather events. Having a backup option is critical when depending on public infrastructure for travel.
Winner:
Overall, public charging is widely accessible for those who need it, but home chargers take the lead in domains of availability and reliability. However, accessibility and availability won’t be a problem if the current projected growth and spread of public charging continue.
Conclusion:
Home and public charging each offer distinct advantages that make them an essential part of the overall EV charging landscape. Home charging provides unparalleled convenience and affordable energy costs. Public charging enables flexibility and rapid refueling for those on the go. Many drivers will ultimately utilize a combination of both public and home charging.
If investing in home charging, be sure to consider installation costs, electrical capacity, and charging speed needs. For public charging, research availability along your routes, costs per session, and backup options in case stations are unavailable. With careful forward planning, both home and public EV charging can be extremely convenient and affordable.
