Everything You Need to Know About Charging an EV at Home

How much does installation cost? How much power do you need? What’s the best home EV charger? Below are some answers.

Charging your car at home is one of the great perks of electric car ownership. A Level 1 (120-volt) and 2 (240-volt) home charging station allows you to plug in a nearly depleted EV in the evening and wake up to a full battery the next morning. Once you've lived with this luxury, you'll never look at gas stations the same way.

But getting to that easy EV living requires some hard (and potentially very expensive) work up front. Installing a home charging station, like so many home improvement projects, can be fraught with unexpected costs, ambiguous information, and flaky contractors. It doesn't have to be that way, though. This guide has all the knowledge you need to ensure you end up with the right home EV charger and a competent installer—all at a fair price.

How Much Does It Cost to Install a Home EV Charger?

Most American homeowners will spend around $1,150 to $2,750 to purchase and install a 240-volt charging station. A good home charger costs $350 to $750 or so, while the typical installation runs between $800 and $2,000 according to nationwide specialists in installing EV charging equipment. The price charged by an electrician for this work varies largely based on four factors: the cost of labor where you live, the power of the charger, the distance between the electrical panel and the charging station, and the complexity of the job. This installation estimate also includes the price of permits.

Some homeowners may be shocked to get a quote above $5,000-$10,000. There are a couple common reasons for these big estimates. An older home may have an outdated electrical panel, or the panel simply may not have room for a new 240-volt circuit. Upgrading to a larger breaker panel typically adds a couple thousand dollars to the job. Things get expensive if the service wires feeding electricity to the house can't deliver enough amperage to accommodate a charger on top of your existing electrical load—especially if the lines are buried underground. Replacing these wires means getting your local utility involved, which also may stretch the project timeline by several months.

Electricians estimate that 20 to 30 percent of home EV charger installations today require a panel upgrade or a load-management system. If you find yourself in one of these pricey predicaments, you have a few money-saving options that we cover later in this story.

What Features Should I Look for In A Home EV Charger?

Choose the unit that best suits your budget! Here's a list of features that everyone should consider:

• A cord that's 20 feet or longer: A long cable gives you flexibility. In a two-car garage, you can often charge vehicles in either parking spot with a single station. If your home charging station is close to a garage door, a long cable will also allow you to plug in a vehicle parked outside. A long cord also future proofs your installation if your next plug-in car has the charging port in a different location than your current vehicle.
• Underwriters Laboratories (UL) or Intertek (ETL) Certification: EV chargers that have been vetted by these trusted, independent safety organizations have been tested to ensure that they meet industry safety standards. Many of the cheapest home charging stations and mobile charging cords forgo these certifications to keep the price down. Considering that a faulty charger could lead to an expensive repair bill or, worse, a house fire, we wouldn't risk using an unproven unit.
• Wi-Fi Connectivity: We think an internet-connected home charging station is unnecessary for most EV drivers, but there's a segment of power users who want the data and control offered by so-called "smart" chargers. These units track the energy used during each charging session and calculate the cost of the electricity. They also allow you to set a charging schedule so, for example, you can plug in a car at 6 p.m. but delay charging until 9 p.m. This will be valuable for anyone on a time-of-use utility plan, which offers cheaper electricity rates during off-peak hours. Note, however, that many EVs and plug-in hybrids also have these charge-scheduling features built into their infotainment systems.
• The Right Amount of Power: A charging stations' power output, measured in kilowatts, determines how quickly it can charge an EV. However, there are a couple reasons that more power (and the resulting faster charging) isn't necessarily better. Read on to figure out how much power you'll want from your charging station.

How Many Kilowatts Do I Need?

We recommend 9.6 kilowatts for most drivers, which will add about 29 miles per hour of charging for a midsize crossover SUV. We consider 11.5 kilowatts nice to have and 7.2 kilowatts the minimum, unless you have extenuating circumstances. Keep in mind that when it comes to charging at home, speed (and hence power) isn't all-important. If your vehicle is regularly parked for eight to 12 hours, you should have no problem waking up to a full charge whenever you want it. Most EV drivers rarely charge from empty to full. It's better for the longevity of the battery to charge from 30 to 80 percent for daily needs and to only use the full capacity of the battery when you need the extra range for long trips.

For a more rigorous assessment of how high you can go, start by figuring out the maximum power your vehicle can accept for AC or Level 2 charging. You may have to hunt for this figure in an automaker's technical specifications or on forums, as many manufacturers don't include it in the owner's manual. This number varies between 6.6 and 19.2 kilowatts, with most of today's EVs limited to 11.5 kilowatts. Larger electric trucks can often charge at the highest power.

Next, work with an electrician to determine what your home and wallet can support. The difference between 9.6 and 11.5 kilowatts may not be worth the added cost of upgrading your electrical service or installing a load-management system. More power also drives up the cost because it requires thicker, more expensive wiring between the panel and charging station. If you have the money and the excess electrical capacity to accommodate a more powerful charger, you might consider going big to prepare for a future time when you might own multiple EVs or one with a larger battery and faster charging capability. You don't need to worry about hurting a car by plugging it into a charging station that provides more power than your car can handle. The vehicle will communicate with the charging station and never draw more power than it can accept.

How Many Amps Do I Need?

Talking about both amps and kilowatts is redundant. If you tell us you have 10 toes, we know you have two feet. Similarly, if you tell us you want to charge at 9.6 kilowatts, we know you want to charge at 40 amps. This is simple math. To calculate power in kilowatts, you multiply amps by volts and divide by 1,000. For a single-family home in America, you'll almost always use 240 volts in this calculation.

If you're checking your electrician's work, know that the circuit breaker for a charging station is always 125 percent larger than the amperage that you'll charge at. As an example, a 9.6-kilowatt charger delivers 240 volts at 40 amps, but the unit will be wired with a 50-amp breaker in your electrical panel.

Should I Hardwire My EV Charger Or Install A 240-Volt Plug?

In the past, we've extolled the virtues of installing a NEMA 14-50 outlet for a home EV charger. It allows you to take a charging station with you if you ever move or replace it without hiring an electrician. You can also use that outlet for an occasional-use device, such as a welder or heater.

The pros have a different opinion. Most charging-station installers recommend hardwiring all wall chargers to prevent nuisance tripping. What's nuisance tripping? Most UL- and ETL-certified Level 2 chargers come equipped with internal ground-fault protection to cut power if there's a surge in the system. At the same time, most local electrical codes require the use of a ground-fault circuit-interrupting (GFCI) breaker when adding a 240-volt outlet for charging an EV. Having two GFCIs on the same circuit can cause the circuit breaker to cut power unnecessarily. That's a major nuisance when you wake up to discover your car hasn't changed overnight.

If you do go with a plug-in installation. Make sure that the electrician uses a commercial grade plug. It's probably $100 instead of $10, but it's designed for that use. Price explains that the cheaper outlets aren't intended to be used continuously for 8 to 12 hours, which is a common occurrence when charging an EV. These cheap outlets also don't hold up to frequently plugging in and unplugging a charger. If the electrical connections come loose, heat can build up and possibly even start a fire. A properly installed charging station—either hardwired or plugged into a quality outlet—significantly reduces this risk.

How Do I Find a Good Electrician to Install My EV Charger?

Like any home improvement job, you'll want to get a few quotes to compare prices and gauge how each electrician will approach the job. Read online reviews and ask friends for recommendations. Regardless of who you hire to do the job, two questions you can use to weed out riff raff: "If the answer to, 'Are you doing a load calculation?' or 'Are you pulling a permit?' is 'no,' irrespective of cost, go elsewhere."

Can I Charge My EV By Plugging in To A Standard 120-Volt Outlet?

Technically, yes. But using a 120-volt cable as your main charging station is only practical if you have a short daily commute—around 30 miles or less—and charge frequently. That's because Level 1 charging typically adds three miles or less of driving range for every hour of charging. In extreme cold, you may merely maintain the charge you started with when you first plugged in.

You may be tempted to use a 120-volt outlet for day-to-day charging with occasional visits to public Level 2 and 3 charging stations. There are a couple problems with this approach. Planning your week around a four- to 10-hour charging session at a Level 2 station quickly becomes a pain. Using DC fast chargers cuts down on your idle time, but it can cost three times as much as home charging, and it isn't good for the long-term health of the battery to use these high-power stations frequently.

My EV Came with A 240-Volt Charging Cable. Can I Use That as My Home Charging Station?

Yes. These cords are often billed as mobile charging cables, but they can be used as your regular charging station at home. The units that support 240-volt charging are often limited to 7.2 kilowatts, so they won't deliver the fastest possible home charging, but it will be adequate for most users. If the power electronics box can be mounted to the wall, be sure to do that to reduce the strain on the outlet.

An Electrician Quoted Me $10,000 To Install an EV Charger. What Are My Options?

If an electrician tells you that you need to spend thousands of dollars upgrading the electrical service wires coming into your house, don't panic. Smart EV charging stations that, when paired with a $249 power meter, can throttle how much power they draw to ensure your house's main breaker doesn't trip. If your electrical panel doesn't have two empty breaker slots for a new 240-volt circuit, there's hope on the horizon. A Meter Collar allows you to pull power for an EV charging station directly from your electric meter, bypassing your panel.

Other Tips for Installing A Home EV Charger

If you're sure you'll be buying an EV soon, we recommend starting the charger-installation process before you've taken delivery of your new car. As a rule, expect it to take between four and eight weeks from when you first contact an electrician to when the job is done. If you don't have reliable home charging, those first few weeks as an EV newbie can be frustrating and intimidating.

?/Be aware, though, that some automakers include a charging station or a stipend that can be applied toward installing one when you purchase an EV. In these instances, you'll probably have to wait until the paperwork is signed to start the process. You'll also want to check if your state, city, or utility provider offers any rebates, incentives, or tax credits for purchasing or installing a home EV charging station. In some locales, you may be able to recoup the entire cost of the unit and the installation.

Finally, make sure you understand your rate plan with your electric utility. Adding an EV to your fleet is going to make your electric bill climb regardless of when you charge it. But if you're on a time-of-use plan, plugging in at the wrong time of day can double the cost to charge your car.