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Frequently Asked Questions about Electric Vehicles (EVs)

My friends here in Bakersfield and elsewhere have asked me many questions about driving electric. There are many web sites that explain what EVs are, how to use them, how to evaluate them, and how to get the most out of them. Nevertheless, I've chosen to include some of the questions I've been asked. There are many more. I'll add to this list as time permits. I've also written extensively about our use of EVs and our adventures driving EVs. Much of the information below and more can be found in those articles. Search for my name in the following sections of this web site: Electric Vehicles and EV Trip Reports.

The Cost of EVgo and ChargePoint Fast Chargers are Different, which is Better?

EVgo, Blink, Electrify America, ChargePoint and others offer DC Fast Charging (DCFC). Each bills differently for a charge. Some charge a connection fee and a fee per kWh. Others just charge per kWh. No one charge network is better than other in terms of what it costs to charge. When you need them, you need them, and you use them, paying what they demand.

Nearly all EV users charge nearly all the time at home. EVs are not gassers. You don't have to go to a filling station. You "fill up" at home.

You only use DCFC when you are a long way from home. Then you need them and you pay what they cost to get to your destination. Over the course of a year, the costs are minuscule.

Last year we spent less than $100 buying 170 kWh from DCFC stations. We drove a total of 10,000 miles during the first year of leasing our Bolt, including trips where we charged at DCFC stations and others. (We did charge overnight at a few motels at 240 volts where the electricity was free and we charged a few nights where we had to pay a nominal fee.) We consumed 2,050 kWh at home. Thus, of our total charging for the year, DCFC stations accounted for less than 10%.

EV drivers keep the big picture in mind. Driving an EV is cheaper than driving a gasser, even when occasionally fast charging on a road trip.

We take a lot of road trips in our EV where we need to charge along the way. (Some of our round trips are more than 500 miles. See EV Trip Reports for more details.) We never shop for the cheapest charger just as we never shopped for the cheapest gas on a road trip in a gasser. We find a convenient station, log-in to the charge network, and charge our car.

There's an old adage that's appropriate here: Penny wise and pound foolish. Drivers needn't worry about buying electricity occasionally from a fast charger when they are saving so much throughout the year by charging at home.

How Much Electricity Can I Get from a Fast Charger?

That depends upon a lot of factors: the car, the State-of-Charge (SOC) of the car, and the charge station. However, we can make some simple assumptions for typical non-Tesla cars today at typical stations. Most stations limit you to 30 minutes for one session. That's one-half hour. The cars store kilowatt-"hours" in the traction battery. The stations are rated in "kilowatts" (kW). Today's "typical" station is 50 kW. Thus, if you charge at a 50 kW station for 1/2 hour, you can expect about 25 kWh.

That's just a ball park number. I use it, but it won't tell you exactly how much to expect. For example, many "50 kW" stations are not 50 kW but only 40 kW. (No. I am not going to explain why that is.) Further, a true 50 kW station doesn't dispense 50 kW to your battery because of inefficiencies. You're more likely to get something like 44 kW. So, for a 30-minute charge you will get 22 kWh.

Sort of. How much you actually get from a dispenser depends upon your car and when in the charge-discharge cycle you arrive at the dispenser. If you arrive at a charge station to "top up" a battery that's already largely filled, the car will ask the charge station for a limited amount to protect the battery. The car may ask for less than 10 kW from the charging kiosk if your battery is nearly full.

Ok, So What Does It Cost to Charge at a Fast Charger?

EVgo, Blink, Electrify America, ChargePoint and others offer DC Fast Charging (DCFC). Each bills differently for a charge. Some charge a connection fee and a fee per kWh. Others just charge per kWh. And those charges may vary around the country.

Last year we paid from $0.40 to $0.70 per kWh delivered to the car here in California. Our average for the year was about $0.50 per kWh. We find that a reasonable price for a necessary service.

Some people may complain that those charges are far more than what they pay at home. That's true. But at home you're only charging at 240 volts at up to 40 amps. At a fast-charging station you're charging at 400 volts and at 125 amps--or more. And all that is at DC. Someone has to pay for all the equipment necessary to do that, as well as install it, and to service it. This costs money and someone has to pay for it.

At Home, Does it Cost the Same to Charge at 120 V and 240 V?

Yes. The utility already delivers 240 volts to your home. That is split into circuits that use either 120 volts or 240 volts. It doesn't matter to the utility whether you use 120 or 240 volts. They just sell you electricity in units of kWh. You can run your toaster with 120 volts, but you'll need 240 volts to run an electric stove, electric dryer, or electric hot water heater. You can charge your car at either voltage, but it will take a very long time at 120 volts. Most people charge their EVs overnight at 240 volts. Charging today's EVs at 120 volts will take days.

When Plugged In On-the-Road, Can Someone Unplug Me without Permission?

Yes, this can happen on Level 2. Many EVs have a charge cable lock that prevents someone else from unplugging your car from a Level 2 (208-240 V) charge station. However, it is good EV etiquette not to use this feature, that is, to turn the lock off if the default is on. There can be good reasons to unplug you. For example, if you're away from the car and the car is finished charging, you have no right to hog the charger, preventing someone else from charging.

If you're at a DCFC station, the car locks the plug once it communicates with the dispenser. This is a safety feature. If the car is finished charging or it has been 30 minutes, the dispenser will stop the session and tell the car to unlock the plug. So, no, someone can't typically "unplug" a DCFC plug without taking a few steps. They can wait until the session is done, and then unplug you. Or they can tell the dispenser you are done by ending the session and then unplugging you.

It is good EV etiquette to have your cell phone number on the windshield of your car or to sign-in to PlugShare so that others know how to reach you if they need to plug in while you're away from your car.

On the flip side it is permissible to unplug someone if their session is finished and they are not around to do so. However, always check the windshield or PlugShare to see if the driver has left a message on how to get in touch with them.

However, driving electric is new. Some don't know good EV etiquette. And, as in all things in life, some don't care to know.

What do Volt, Amp, and Watt Mean Relative to EVs?

Watts or kilowatts (kW), and kilowatt-hours are all you need to know at the beginning.

Kilowatt-hours, kWh, is the size of the battery. In short, you don't want anything less than 60 kWh. You can make a case for 40 kWh, but for nearly all North Americans, 60 kWh is the minimum battery size that's practical in 2019.

kW is the size of the motor and in the mid-price range they're all the same or nearly so. Most people can safely ignore this. kW is also the rate at which the car charges at fast chargers. Again, the difference isn't significant in 2019, so you can ignore this too.

However, kWh--that's important!

What are the different levels of charging?

There are two levels of charging that are used frequently: Level 2, and DCFC. Level 2 is for charging at 240 volts and is typically done at home overnight.

DCFC is DC fast charge capability, measured in kW, and is found at stations in shopping centers or along major highways. DCFC stations charge at 400 volts or more.

First, never, ever, buy an EV without fast charge capability. Never! Even if you don't plan to use it, the person who buys the car after you may want to--or need to--use it. The car simply has more utility if it has DCFC capability. No car should be manufactured without it. That they are is an indictment against the auto companies for their shortsightedness.

For Level 2, the power dispensed at 240 volts is limited by its source as well as the car as measured in amps. More amps equals more power. The 2015 Nissan Leaf could draw as much as 27 amps, or 6.5 kW, delivering about 6 kW to the battery. The Chevy Bolt will draw 32 amps or 7.7 kW, feeding 7.4 kW to the battery.

For DC fast charging, mid-price range EVs in 2019 can effectively use the same power. The Kona can draw 70 kW, the Bolt 55 kW. That's not a big enough difference to be important. Tesla charges at 125 kW--that's twice the Bolt. That's a big difference--and a good reason that many get a Tesla.

Do You have to have a Smart Phone to Drive an EV?

A smart phone is helpful, particularly on drives where you need to charge on the road. But, no, you don't need a smart phone to drive an EV.

Home charging is simple. Just plug in. If you want to charge at a Level 2 kiosk that requires payment, you nearly always will need an RFID card. These are often provided for free upon request and are then tied to your credit card. Sometimes you can telephone the company and give them your credit card information over the phone and they will then start the charge remotely.

At DCFC stations you either use a credit card (rare) or RFID cards that you get from the network provider. I have several. They work great. A smart phone is a big plus, but you don't need it.

What are the DCFC Standards in North America?

There are three charging standards in North America: Tesla, CHAdeMO, and CCS.

The Tesla standard only applies to Tesla.

CHAdeMO is the Japanese standard used by Nissan and a few other manufacturers. Nissan's Leaf uses the CHAdeMO standard for fast charging.

CCS is Combined Charging Standard used by American and German manufacturers. It's also called the Franken plug. The Chevy Bolt uses the CCS standard for fast Charging.

Most non-Tesla fast charging stations have kiosks or dispensers for both CHAdeMO and CCS. Both work equally well.

How Do I Find Charge Stations?

Each charge network maintains a web-based mapping application. However, most EV drivers use PlugShare, the crowd-sourced mapping application. PlugShare is dependent on drivers using it to update station availability, issues that a driver might encounter, places nearby to eat, photos of the station, and their charging experience.

As the name suggests, you can also post your own EVSE (Electric Vehicle Supply Equipment) to the web site and "share" it with other drivers. In the early days of EVs, this was an important function. With more DCFC stations available, this is less useful now. Our home charge station is still listed on PlugShare and we have had a few people use it over the years.

PlugShare will display commercial and free Level 2 stations, home charge stations, and DCFC stations, depending upon the settings used.

Driving Modes, What are they?

In most cases newbies don't need to know this. EVs include varying levels of regenerative braking. Because EVs are electric and the battery and electric motor are controlled by a computer, you can select the level of regenerative braking. You can do this through a touch screen or via the "shift" lever, when the car is at rest, or when the car is moving through a paddle on the steering wheel.

The 2015 Nissan Leaf had a "drive" mode on the "shift" lever, but in addition it also had a "B" model on the shift lever for driving with increased regenerative braking over that found in drive.

The Chevy Bolt's default is "drive" mode on the "shift" lever, but it also includes a second level, "L" for increased regenerative braking. "L" will bring the Chevy Bolt to a stop and will hold it from creeping on a level surface. If that's not enough regenerative braking, there is also a paddle on the steering wheel. Pull the paddle and it will quickly bring the Bolt to a halt.

Regenerative breaking charges the battery when you want to slow the car down. With it, you can drive with only one pedal--the accelerator pedal. See my posts about this in Driving the Chevy Bolt EV--Our Impressions. It's perfect for mountain driving--as on our trip to Death Valley. Coming down Towne Pass we gained 2.75 kWh after dropping 3,000 feet.

“DC" and “AC" Charging, What's This about?

Batteries store DC. Household electricity is AC.

All EVs come with an "onboard" charger that takes AC and converts it to DC that then charges the battery. (The onboard converter is not the thing in the trunk. That is a "mobile" charge cable.) At DCFC stations, the plug feeds DC directly to the battery. It does not go through the converter.

What are miles/kWh or How do Miles/kWh translate to Miles per Gallon?

Newbies don't need to know this. I compare the cost of driving a Nissan Leaf to a Toyota Prius we'd driven for six years where I need to calculate the cost per mile of gasoline. I'll post a link here shortly.

If the question is about efficiency, all EVs are efficient. If you want most efficient, buy a low drag Tesla. You can read my trip reports where I note the efficiency of each leg of trips in various EVs. There's a different efficiency depending upon whether you're going uphill, downhill, or on the flats.

I average about 4 miles/kWh. That's all most drivers need to know. It's less at freeway speeds. It's less against a head wind. It's more downhill, with a tail wind, and at slower speeds.

This is a useful number to know. If you need to drive 100 miles, you will need at least 25 kWh (100 miles/(4 miles/kWh)= 25 kWh) and possibly more.

Tesla drivers use a different metric for efficiency. It is the inverse of miles/kWh. For example, 4 miles/kWh equals 0.25 kWh/mile.

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