EV Charging Basics. Electric car charging units

EV Charging Basics

Learn more about different charging options for electric vehicles (EVs), plus where you can find rebates to help cover purchase and installation costs.

EV Charger Types

EV chargers are classified into three categories: Level 1, Level 2 and direct current (DC) fast chargers.

EV chargers are classified into three categories: Level 1, Level 2 and direct current (DC) fast chargers.

Important differences include:

  • Input voltage. This is how much power a charger requires to operate and is expressed in volts.
  • Power output. This is how much power a charger can generate and is expressed in kilowatts (kW).
  • Charging speed. This is the number of miles added to the EV’s battery per hour of charging and depends on the charger’s power output.
  • Equipment and installation cost. While basic EV chargers are inexpensive and can be plugged into a standard outlet, others have higher upfront equipment and must be installed professionally by an electric vehicle service provider (EVSP).
  • EV power intake. Depending on your EV, the power output pulled from a charger (in kW) may be limited by how much the EV’s battery can withstand. Check your vehicle’s specifications to know which charging level your vehicle can use.

Numerous manufacturers produce EV chargers, with a variety of products, price points, applications and functionality. Because of these differences, it is important to choose an EV charger that fits your intended use and budget.

Direct Current Fast Charging

How fast is DC fast charging?

Depending on the EV, DC fast chargers can currently produce a 10-80% charge for a 300-mile range battery in approximately 20 minutes (~540 miles of electric drive per hour of charging).

What is the input voltage for a DC fast charger?

Currently available DC fast chargers require inputs of at least 480 volts and 100 amps, but newer chargers are capable of up to 1000 volt and 500 amps (up to 360 kW).

How much do DC fast chargers cost?

A CALeVIP Cost Data analysis found that the unit cost per charger for rebate recipients ranged from a minimum of 18,000 to a maximum of 72,500. The mean and median unit cost per charger was 29,135 and 23,000, respectively.

In addition to higher equipment costs, DC fast charger installations require a commercial electrician from the initial planning phase due to the electrical load and wiring requirements.

Is a DC fast charger the right EV charger for me?

DC fast chargers are the highest-powered EV chargers on the market. They often are used as range extenders along major travel corridors for long-distance trips and in urban environments to support drivers without home charging or very high mileage drivers. At current charging speeds, they are ideal for places where a person would spend 30 minutes to an hour, such as restaurants, recreational areas and shopping centers.

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It is important to note that not every EV model is capable of DC fast charging, and therefore, they cannot be used by every EV driver. Further, DC fast chargers have multiple standards for connectors, whereas there is only one common standard for Level 1 and 2 charging (SAE J1772). DC fast chargers have three types of connectors: CHAdeMO, CCS and Tesla, though CCS is increasingly becoming the industry standard.

Level 2 Chargers

How fast is Level 2 charging?

A Level 2 charger can currently produce a full charge for a 300-mile range battery in about 6-8 hours and is perfect for destination and overnight charging.

What is the input voltage of a Level 2 charger?

Level 2 chargers typically require 220V or 240V service.

What is the power output of a Level 2 charger?

Level 2 chargers are available with a variety of power outputs from 3 kW to 19 kW, which can sometimes be adjusted.

How much do Level 2 chargers cost?

CALeVIP Cost Data show that rebate recipients reported average L2 equipment costs ranging from 685 to 6,626 per connector. The mean and median were 2,976 and 2,884 per connector, respectively.

Is a Level 2 charger the right EV charger for me?

Level 2 chargers are typical solutions for residential and commercial/workplace settings. Most offer higher power output than Level 1 chargers and have additional functionality.

Non-networked vs. networked chargers

In general, Level 2 chargers are distinguished between non-networked chargers and networked chargers.

Networked chargers have advanced capabilities, such as charge scheduling, load management and demand response. They are more common in commercial/workplace settings where payments are required or at multiunit dwellings (MUDs) where the property’s electricity bill is shared by multiple residents.

They may be designed for indoor or outdoor use (e.g., NEMA 3R, NEMA 6P, NEMA 4x rated).

Some models of networked chargers also can limit charging to certain hours, which allows the operator to maximize a time-of-use (TOU) electricity rate structure and only allow charging when electricity is the cheapest (usually sometime between 9 p.m. and 6 a.m.). This type of control also increases the likelihood of participating in utility demand response programs.

Some of the enhanced features of a networked Level 2 charger include remote access/control via Wi-Fi or cellular connection, access control/ability to accept multiple forms of payment, load balancing across multiple chargers and more. Additionally, California will soon begin allowing the use of submeters already embedded within networked chargers to bill electricity use. For more information on submetering, visit the California Public Utilities Commission (CPUC) website.

Non-networked Level 2 chargers are used both in single-family residences and MUDs. They may be designed for indoor or outdoor use (e.g., NEMA 3R, NEMA 6P, NEMA 4x rated). Non-networked Level 2 chargers are useful for installations at MUDs or commercial sites that are powered by the residents’ or tenants’ subpanels.

In this case, any electricity used by the chargers will be charged to the individual’s electricity bill, thus eliminating the need to separately meter the chargers. Further, when electrical capacity is available, non-networked Level 2 chargers are useful for site hosts that need higher power than Level 1 charging but do not have a large budget.

How Long Does It Take to Charge an Electric Vehicle?

There is no simple answer, but knowing the variables will help you better estimate the time it takes for an EV fill-up.

Figuring precisely how long it takes to charge an electric car is akin to asking, How long does it take to cross the country? It depends on whether you’re on a plane or on foot. Recharge time is dependent on a host of variables, many of them nuanced—even the length of the charging cable can influence it—that make providing a precise answer impossible. But we can give you some reliable guidelines.

Ignoring the more minute variables, the charging time of a vehicle comes down to a few primary factors: power source, the vehicle’s charger capacity, and battery size. Ambient conditions play a smaller part, with both cold- and hot-weather extremes adding to charge time.

Factors That Affect Charging Time

Charger Level

Let’s start with the power source. Not all electrical outlets are created equal. The common 120-volt, 15-amp receptacle in a kitchen is to a 240-volt outlet that powers an electric dryer as a squirt gun is to a garden hose. All electric vehicles can, theoretically, charge their large batteries off the standard kitchen outlet, but imagine trying to fill a 55-gallon barrel with a squirt gun. Recharging an EV battery with a 120-volt source—these are categorized as Level 1 according to SAE J1772, a standard that engineers use to design EVs—is measured in days, not hours.

If you own or plan to own an EV you’ll be wise to consider having a 240-volt Level 2 charging solution installed in your home. A typical Level 2 connection is 240 volts and 40 to 50 amps. While fewer amps is still considered Level 2, a 50-amp circuit will maximize most EV’s onboard chargers (more on those in a minute). Because, if you’re not maximizing the effectiveness of the vehicle’s onboard chargers, a lower-than-optimal power source is essentially a restrictor plate that lengthens the charge time.

For the absolute fastest charging possible, you’ll want to plug into a Level 3 connection, colloquially known as a DC fast charger. These are the EV equivalent of filling that barrel with a fire hose. A certifiably lethal current of DC power is pumped into the car’s battery, and miles of range are added in short order. Tesla’s V3 Superchargers pump out up to 250 kW and Electrify America’s automotive defibrillators fire out up to 350 kW of heart-stopping power. But like all charging, the flow is throttled back when the vehicle battery’s state-of-charge (SoC) is nearing full. And vehicles’ ability to accept DC charging varies widely. The Porsche Taycan, for example, can charge at up to 270 kW, while a Chevy Bolt EV can manage only 50 kW.

How Much Range Does a Fast-Charger Add in a Half-Hour?

Generally speaking, when an EV battery’s SoC is below 10 percent or above 80 percent, a DC fast charger’s charging rate slows considerably; this optimizes battery life and limits the risk of overcharging. This is why, for example, manufacturers often claim that fast-charging will get your EV’s battery to 80 percent charge in 30 minutes. Some vehicles have a battery preconditioning procedure that ensures the battery is at optimum temperature for Rapid charging while en route to a DC fast charger. So long as you utilize the in-car navigation system to get you there, that is.

Maximum Charging and Driving Range

That last 20 percent of charge may double the time you’re hooked up to the fast charger. The time-consuming affair of completely filling the battery via a DC charger makes these units best utilized on those days when you are traveling a long distance and need additional electricity to reach your destination. Charging at home overnight–sometimes called top-up charging–is a better solution for getting the juice you’ll need for daily, local driving.

Battery Size

As the hunt for range supremacy continues, the battery capacity of some EVs has ballooned to absurd levels. Others are targeting increased efficiency. This plays a massive role in charging time. Upsize our barrel to an 85-gallon unit. Even with a fire hose, it’ll still take longer to fill than the smaller 55-gallon barrel. While a GMC Hummer EV is built on an architecture capable of 350-kW intake, filling its 212.7-kWh battery compared to the 112.0-kWh pack found in a Lucid Air Grand Touring requires exponentially more time, even if the charging rate is similar. The Lucid can travel over 40 percent further on a charge while having 100 kWh fewer in its battery pack than the Hummer. Efficiency, indeed.

No doubt someday manufacturers will settle on a single metric for expressing charge times. But for now, know that filling up an EV’s battery still takes considerably longer than topping off a gas-powered car’s fuel tank no matter how or where you do it.

There is a common misconception that the thing you plug into an electric car is the charger. In fact, there’s a battery charger in the car that converts the AC electricity from the wall into DC electricity to charge the battery. Onboard chargers trickle power into the battery pack safely and have their own power ratings, typically in kilowatts. If a car has a 10.0-kW charger and a 100.0-kWh battery pack, it would, in theory, take 10 hours to charge a fully depleted battery.

To gauge the optimal charge time of a specific EV, you divide the battery capacity’s kWh number by the onboard charger’s power rating, then add 10 percent, because there are losses associated with charging. This is assuming the power source can maximize the vehicle’s charger.

Typical onboard chargers are at least 6.0 kilowatts, but some manufacturers offer nearly twice that, and the cream-of-the-crop have more than triple that figure. The current Tesla Model 3 Performance, for instance, has an 11.5-kW charger, which can take full advantage of a 240-volt, 60-amp circuit to recharge its 80.8-kWh battery, while the rear-wheel-drive Model 3 comes with a 7.6-kW charger. Doing the recharge-time math indicates that it will take nearly the same time to fill the two cars’ batteries, though the Performance model’s is roughly 30 percent larger. The beauty of a well-paired electricity source and onboard charger is that you can plug your EV in at home with a nearly depleted battery and have a fully charged steed waiting for you in the morning. You can also find approximate recharge times on some EV manufacturers’ websites.

K.C. Colwell is Car and Driver’s executive editor, who covers new cars and technology with a keen eye for automotive nonsense and with what he considers to be great car sense, which is a humblebrag. On his first day at C/D in 2004, he was given the keys to a Porsche 911 by someone who didn’t even know if he had a driver’s license. He also is one of the drivers who set fast laps at C/D’s annual Lightning Lap track test.

Jacob Kurowicki’s love affair with cars doesn’t end at track weapons and posh land yachts, but rather extends to the dopey and eccentric. Pining for a Pontiac Sunfire GT as a child was the first indicator, but an ongoing desire for a Lamborghini LM-002 is the kicker. He luckily found a home in the Car and Driver testing team that allows him to further develop his love for the automotive world and the oddities that come with it.

The Difference Between Level 1 2 EV Chargers

Whether you already own an electric vehicle (EV) or are looking to purchase one in the near future, the biggest topic of concern for most drivers comes down to where charging will occur and how much it will cost.

Despite having an environmentally friendly vehicle that cuts reliance on gasoline, using a Level 1 home charger is not reliable or convenient for most EV drivers. Instead, having a faster, Level 2 charging station can reduce range anxiety and calm logistical fears, as you become less reliant on charging on the go.

But what exactly is a Level 2 car charger and why does it present better value than its Level 1 counterpart?

Types of EV Charging Connectors: What is Level 2 Charging?

Vehicle owners are often supplied with Level 1 chargers from automobile manufacturers at the time of purchase to use at home with 120v standard outlets. However, upgrading to a Level 2 EV charger is a good and practical investment. A Level 2 charger is like having your own gas pump in your garage, but it is a Smart appliance that charges your vehicle. An added convenience: not only is a Level 2 car charger ready when you need it to be, you can save on electricity by charging during lower rate times.

A Level 2 EV charging station delivers an electrical current from an outlet or hardwired unit to the vehicle via the connector, similar to a standard-issue charger. Level 2 car chargers use a 208-240v power source and a dedicated circuit — potentially up to 60 amps. However, 32 amp charging stations like the EvoCharge EVSE or iEVSE Home Smart EV Charger offer more flexibility and potential costs saving by requiring a lower 40 amp circuit.A Level 1 will deliver around 1.2 kW to the vehicle, while a Level 2 charger ranges from 6.2 to 19.2 kW, with most chargers around 7.6 kW.

EvoCharge EVSE Level 2 EV Charging Station

EvoCharge’s standard EVSE Level 2 charger is a simple plug-and-charge solution for the basic needs of charging your vehicle at home quickly and safely.

Shop EVSE

How Fast is a Level 2 EV Charger?

While a Level 1 charger will typically get 4 miles of driving range per hour of charge, a Level 2 charger will get an average of 32 miles of driving range per hour of charge. This means that you’re charging up to 8 times faster with a Level 2 charging station. Typical charging time for a Level 2 EV charger is around 3-8 hours from empty to full while the average Level 1 EV charger will take 11-20 hours to fully charge.

Level 2 chargers will deliver 6.2 to 19.2 kW versus the 1.2 kW you get with a Level 1. For a direct comparison, check out this resource to see how fast a Level 2 charger is compared to its counterpart.

When One Might Consider a Level 1

A Level 2 EV charger needs a 240v outlet, which many new homes or new multi-unit homes and building standards require. If you do not have a 240v outlet, a certified electrician can easily install one and the cost can sometimes be offset through local, federal, state or utility companies which offer rebates and financial incentives for the charger, installation, or for charging during lower electric rate times.

Additionally, Level 2 charging stations like the EvoCharge iEVSE Home Smart EV Charger allow you to customize charging schedules with the EvoCharge mobile app to better control charging, lessening your overall cost and making you eligible for further rebates through your municipality so you get faster charging times at a lower cost. The mobile app also provides usage history, multiple vehicle controls, and much more.

Your guide to EV charging

A standard home charging station, whether it is a Level 1 (120 V) station or a Level 2 (240 V) station, will provide pass through AC power to the vehicle for charging. The vehicle will convert this AC power to DC power and utilize the DC power to recharge its batteries. The actual battery charger is on-board the vehicle. EV charging stations essentially act as electrical safety equipment that, first and foremost, ensure safety for the user, then the vehicle, and then the power grid. A charging station implements several layers of redundant safety features to protect the user from potential electrical hazards while connecting and disconnecting the station to the vehicle for charging. Once connected to the vehicle the EV charging station will inform the vehicle that power is available and at what level. From that point the vehicle takes over to initiate and take full control of the power transfer, unless an electrical fault occurs, in which case the station will stop the power transfer immediately.

How do I choose the right EV charger for my EV?

Enphase has created an EV charger selector tool to make it easy for you to find the right EV charger for your EV. The tool will recommend a charger based on your EV make and model. Additionally, you can learn about calculating battery charging times and power acceptance rates.

What’s the difference between a Level 1 and Level 2 EV charger?​

There are two “levels” of chargers (Level 1 and Level 2) used for home EV charging. They deliver different charging speeds for charging your EV at home. Level 1 chargers are very slow, while Level 2 chargers offer faster charging.​

Typically, EVs come with a Level 1 or “trickle” charging station in the trunk of the car for portability. The Level 1 charging station plugs into any standard 120 V household outlet to charge your EV. This delivers a very slow charge and typically provides about 4-5 miles of range per hour of charge. For some drivers this is enough.​

Many EV drivers want the option to charge their EV at a faster rate. Level 2, or 240 V, charging stations offer higher speed charging. Level 2 chargers require a dedicated 240 V line to the charging station, and there are various power levels (and, hence, charging speeds) available from Level 2 charging stations. A Level 2 charging station can provide between 16 to 60 miles of range per hour of charge, depending on the vehicle that is being charged and the charging station being used. ​

To learn more about calculating charging times and EV charge acceptance rates, read our EV charging time article.​

What’s the difference between a hardwired EV charger and a plug-in version?

Some Enphase EV Chargers are designed for hardwired installation and others for plug-in installation. The hardwired EV chargers include service wires which are routed through a three-foot flexible conduit with an additional six inches of wire extensions for easy installation into a junction box. With a hardwired EV charger the installation is more permanent, the EV charger can still be moved, but you would need an electrician to uninstall the EV charger and then reinstall it at your new location. Hardwire Enphase EV Chargers are rated for indoor or outdoor installation.

With a plug-in EV charger, it will come with a high-quality, over-molded 240 V plug attached instead of the flexible conduit included with a hardwired charger. The plug length is 12 inches, the longest length allowed per National Electric Code, and this includes the plug itself in the measurement.​

Additionally, we offer two different types of 240 V plugs—NEMA 14-50 and NEMA 6-50—with our charging stations. For a plug-in installation, the electrician should verify the wiring and upstream circuit breaker are adequate to deliver the EV charger power rating. The electrician should also ensure the receptacle supplied with the product is installed with the EV charger. This delivers the safest installation for a plug-in charger.​

Always use a qualified electrician when installing EV chargers and supporting equipment. To find a local qualified installer, visit our EV charger installer locator.

How do I determine which EV charger will charge my car the fastest?

Three key elements determine how fast an EV battery will charge:

  • Battery size and storage, which differs by EV​
  • Power acceptance rate, which differs by EV​
  • EV charging station maximum power delivery rating, which varies by EV Charger ​

To determine how fast an EV charger will charge a given EV, here are the basic rules to consider:​

  • If the charging station offers less power than the vehicle’s maximum acceptance rate, the charging station would be the limiting factor in determining the charge time. ​
  • If the vehicle’s acceptance rate is lower than the charging station’s maximum output rate, then the vehicle will be the limiting factor. ​
  • To determine your estimated total charge time, you would take your vehicle battery pack rating and divide it by whichever number is lower, the vehicle’s acceptance rate, or the station’s output rate. ​

Most vehicles will provide this information through the dashboard interface once you plug into a charging station.​ You can also get more details about calculating battery charging times and power acceptance rates in our EV charging time article.

Our EV charger selector tool makes it easy to find the right EV charger for your EV make and model.

Are there any rebates or incentives for buying an EV charger?

There are many programs around the country that provide incentives for installing a Level 2 EV charger. Here are the federal, state, utility, and private incentives that we know about: EV charger rebates and incentives by state.

We recommend you contact your local utility or check the US Department of Energy Laws and Incentives website for any other incentives that may be available for installing a Level 2 EV charger.

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Do I need an electrician to install an EV charger?

We recommended that you have a qualified electrician install your EV charger because there are certain electrical requirements for the product itself, wiring size requirements, and local electrical codes that an electrician will have knowledge of, which ensures that the charging station will be installed properly and safely.​

A qualified electrician can also assess the home’s current electrical infrastructure and advise you if there’s any additional work necessary (for example, an electrical panel upgrade in an older home). Most homes will have capacity available, and the work will merely be wiring the station to a dedicated circuit in the case of a hardwired charger or installing an appropriate and safe receptacle/outlet in the case of a plug-in charger.​ To find a local qualified installer, visit our EV charger installer locator.

Can I install an EV charger outdoors?

Yes. For outdoor installations we recommend installing a hardwired 240 V EV charger. All Enphase EV Chargers have a fully sealed NEMA 4 enclosure that provides superior protection to the components inside the charger from outdoor elements.​

We recommend a hardwired EV charger for an outdoor installation as it provides better weather protection for the connection to power. If you install a plug-in EV charger outdoors, we recommend installing a watertight cover over the plug and outlet combination.

We also recommend checking with a licensed electrician to ensure installing a 240 V plug-in EV charger outdoors meets your local codes. There was a change in the National Electric Code requirements at the beginning of 2017 that allowed plug-in 240 V EV chargers to be installed outdoors, however sometimes local codes can vary.

To find a local qualified installer, visit our EV charger installer locator.

Can I charge my EV when it’s raining or snowing outside?​

Yes, the charging head on Enphase EV Chargers are designed to drain water and the inlet on your vehicle is designed to drain water as well. Once the charging head is connected into your vehicle’s inlet, a water-tight seal will be formed.

What is the difference between UL and ETL ratings and why is it important?

These two listings are predominantly about user safety and product quality. UL and ETL are both considered Nationally Recognized Testing Laboratories (NRTL). NRTLs provide independent safety and quality certifications for electrical appliances. UL develops the testing standards and tests to them, ETL tests to UL standards.

Products with UL or ETL listings are recognized as safer than units without these listings. Make sure the logos of one of these testing laboratories are shown directly on the product you purchase to ensure its safety.​

An inspector sign-off on a permitted installation in line with the National Electric Code requires that the EV charger be NRTL listed (in the US that is either with ETL or UL). Enphase uses both laboratories.

Will using an EV charger with a higher output current rating than my EV can accept damage my vehicle?

No, using a higher amperage EV charger will pose no harm to the vehicle. EV chargers are a pass-through, electrical safety appliance. The EV is in complete control of the charge and will only take the power it can accept and no more. The actual charging takes place on the vehicle. Our units will supply AC power to the vehicle and the vehicles onboard charger will convert the AC power to DC power and charge the vehicle’s batteries.

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For example, a Chevy Volt can take in 3.3 kW for charging and the HCS-40 EV charger can deliver up to 7.7 kW. When an HCS-40 EV charger is plugged into the Volt the station will “tell” the Volt how much power is available through the charger’s communication system. From that point the vehicle will take over, activate the charger and accept the power it wants, up to the limit established by the EV Charger.

Some of our customers purchase EV chargers that offer a higher power level than their current vehicle can accept, which allows them to future proof their installation in anticipation of purchasing a vehicle that could accept more power. ​

How much energy does an EV charger use when it’s not charging an EV?

Enphase products consume very minimal power when not in use. We call this “standby power,” and the draw on the HCS EV charger for standby power is approximately two watts. For comparison, leaving an HCS-40 EV charger powered up for about 50 days would use the same amount of power as leaving on a 100 watt light bulb for 24 hours (a very small amount).

Enphase EV Chargers do not come with a power switch because the standby power consumption is so low, and a switch could be forgotten, or accidentally not turned on, resulting in your EV not receiving its charge.

How do I know Enphase EV Chargers will work with my EV?

Enphase EV Chargers work with virtually every EV sold in North America. The industry standard connector in North America is SAE J1772. Commonly referred to as a “J-plug.” All Enphase EV Chargers come with this type of connector and can be used with any electric vehicle.​ While Tesla uses its own proprietary connection interface, they provide a connection adaptor which can also be used with Enphase EV Chargers.

Will an EV charger work with my EV’s onboard timer?

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Yes, our EV chargers provide pass-through electricity and will not supply power to the EV unless the vehicle is requesting a charge. The vehicle is in complete control of the charge and if a timer is set within the vehicle the EV charger, even if plugged into the car, will not supply power to the vehicle until the vehicle requests a charge at the scheduled time.

Note: Our HCS products do not currently work with the charging timers of the Nissan Leaf 2023 and Mercedes-Benz EQS 2022-2023.

How do I find public EV charging stations?

You can visit websites such as PlugShare or Google Maps which allow you to search by address, city, or zip code to find stations in your area. Google Maps and PlugShare both show charging stations along with other helpful information from their respective community of users. The services are also available as apps that you can download to your smartphone for a convenient way to search for stations when you are on the go.

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