Someday, EV charging while on-the-go will be just as convenient as stopping for gas. Until then, charging at home is an important part of EV ownership.
If you’re not able to charge at home, you’ll need to at least make sure that there are compatible fast-charging plugs in a convenient location near you. We'll cover the different types of charging stations and connectors and how to find them in our lesson All About Charging.
If you're not able to charge at home reliably AND there are no convenient alternatives (such as charging at work, or fast-charging stations in places that you visit frequently like your local grocery store) then you may want to avoid fully electric vehicles (for now!) and instead opt for some sort of hybrid. Hybrid vehicles use a combination of gas and electric power, and are an important part of the EV puzzle. There are several types of hybrids, each with their own set of strengths and weaknesses for different driving habits. We'll cover each of these in one of the pages that follow.
First, let's talk about range...
The amount of range that you need isn't as simple as just adding up how many miles you may drive...
There's a well-known saying in the EV community, that you should "buy as much battery as you can afford".
This is referring to the fact that many EVs offer a choice of battery size, and a bigger battery is typically viewed as better. As you might have guessed, bigger batteries cost more. So the value that a bigger battery provides may or may not be worth it to you, depending on your needs and budget.
There are many factors that can affect how much range your car actually gets. The amount of range that a vehicle advertises is only an estimate, and based on simulated conditions. Things like speed, temperature, terrain, and more can turn 200 miles of advertised range into 150 miles pretty easily. (It should be noted, this also happens with gasoline cars -- we just don't typically pay much attention to the total "range" of gas cars.)
Trying to estimate range is tricky. We're about to help you try, but keep in mind that our estimates are just that - estimates - and every car and every situation will be unique.
According to the U.S. Dept. of Transportation, Americans drive an average daily distance of 29 miles. That means that most EVs, even the ones with smaller batteries, have plenty of range for a majority of people, under average circumstances — but are your circumstances average?
To find out how much range you need, you must first have an idea of how far you drive on your busiest days. For the moment, let's forget about any atypical long-distance trips (for instance, if you take a ski trip 2 or 3 times per year). For those types of trips, you're likely to use public charging stations along your route. For now, let's only think about your average "busy" day where you might drive to work, run errands, shuttle around friends or family, etc. How many miles do you drive on those days?
There are several ways to figure this out. One way is to simply start tracking your daily miles over the course of a week or two. At the end of each day, record your car's mileage and then note which days had the longest distances. You'd likely want enough range to cover the mileage you drove on any of those recorded days.
If you'd rather not take the time to track your mileage, you can try to re-create your busiest day using your favorite mapping app. Ask for directions between each place you might go, and record how many miles are driven between them. When finished, add up all of these miles into a total distance. Keep this number in mind as we continue this lesson.
Here's the thing - that total daily mileage number is not the amount of range that you need. Not yet. There are several other factors to consider above and beyond that number. Let's talk about those now.
Extreme temperatures (especially cold) will reduce your EV's available range, and this loss of range should be factored into your needs when buying.
Cold weather makes batteries less efficient, and any use of your car's climate control will draw a lot more power from an EV battery. It's not just keeping your passengers comfortable either, most EVs will also manage the temperature of their batteries to keep them healthy. All of this takes energy, and that extra consumption will reduce your available range on days when the temperature drops (or rises).
The amount of range you might lose will vary. Every vehicle model is different, and it also depends on just how extreme the temperatures get. It's possible that extreme temps can cause your car to lose 50% of its range, possibly more. Your range isn't gone for good of course - when the temperature rises your range will return to normal. Just know that on those very hot or very cold days, you won't have as much range as you're used to.
If you'd like to learn more, Geotab.com has a very informative study on how temperature impacts the range of EVs, with data showing the impact on range as the temperature drops (or rises).
EV charging speeds will vary based on the capabilities of the car, the capabilities of the charging station you're plugged into, and a number of environmental factors.
The speed at which an EV battery charges will depend on several factors that we'll discuss in detail in our lesson about charging. For now, know that an EV will charge much faster when the battery is low, and slower as the battery nears full. This fluctuation in speed is referred to as an EV's Charge Curve.
The amount of charge that a battery has at any given time is called State of Charge. If your car tells you that you have 20% of your battery remaining, your State of Charge = 20%.
An EV battery will charge much faster when the State of Charge is between 0% and 80%. After 80%, it begins to slow down considerably until it reaches 100% (EVs do this to protect the health of the battery).
For example, a car with a very fast charging speed might charge up to 80% in just 20-30 minutes, but it might take an extra 40 minutes to charge that final bit between 80% and 100% (this is just an estimate, every car will be different depending on its Charge Curve).
With this in mind, let's say that you buy a car with 200 miles of range, and you commonly need ALL of those 200 miles at your disposal on any given day. You may want to consider buying a car with 20% more range than you actually need (in this example of 200 miles, you'd want 20% more or 240 miles total). This way, the car will charge quickly to 80%, giving you the ~200 miles that you need faster, before slowing down to fill those final (extra) ~40 miles.
Keep in mind, different cars are capable of charging at different speeds, and the faster a car is capable of charging, the more dramatic this effect may be. We'll cover charging speeds in an upcoming lesson.
For now, let's talk about degradation...
EV batteries may lose some of their capacity over time, reducing your available range. This future range loss should be considered now, so you have enough for your needs later.
Batteries like those used in EVs can degrade over time. This can lead to reduced range as the battery gets older. The amount of range lost will vary based on a number of factors that we'll cover in the pages that follow.
Most manufacturers guarantee that their EV batteries will retain a minimum amount of their original capacity during their warranty period. For example, at time of writing the best selling EV in the United States (a Tesla Model Y), is guaranteed by the manufacturer to maintain a minimum of 70% of its original battery capacity after 8 years or 120,000 miles. Many other EV manufacturers offer similar guarantees, but may phrase their warranty differently. For example Nissan guarantees the capacity in their latest Leaf models will not fall below "nine segments as shown on the vehicle's battery capacity level gauge" for a period of 96 months or 100,000 miles (whichever comes first). Nissan Leaf models have 12 total segments on their battery level gauge, which would seem to imply an approximate capacity guarantee of 75%.
While 25%-30% range loss might seem dramatic, these numbers are not necessarily what you should expect - they are instead what these manufacturers are willing to guarantee. For example, let's take a look at some real-world numbers from one of the EVs that has been around the longest. The Tesla Model S has been on the market since 2012, and is providing some of the best data on capacity loss over time with high mileage. Tesla claimsthat on average, their Model S and X vehicles lose only 10% of their original battery capacity after 200,000 miles. A group of Dutch Tesla owners have collected data that seems to support these claims, showing battery degradation less than 10% after 250,000km. Keep in mind, this is just one example of a single EV model. Different EVs use different chemistries in their batteries, and are engineered to use their power differently. These figures will vary from model to model and (like any car) will depend on how well a particular vehicle was cared for. Before deciding on a car model, it's worth conducting an internet search on that model's history of degradation.
By the way, losing "range" over time is not a concept exclusive to EVs - gas vehicles tend to go through something similar, unless they are exceptionally well maintained.
The lesson here is this: if you plan to keep your EV for the long term, you’ll want to account for some approximate degradation in your mileage needs, assuming that those needs will stay the same over time. Always be sure to check the warranty of the car you're considering, and be aware of how much battery capacity the manufacturer guarantees, and for how long.
If you're shopping for a used EV you'll want to consider that the car may have already lost some capacity from its original advertised range. To be sure of the amount of range a specific car still has, you'll want to inspect how much is indicated when the car is fully charged before you commit to buying it.
If the answer is no, you'll want to ensure that there are compatible fast cha in a convenient location near you. While an EV that charges at home can easily be more convenient than a gas car, an EV that relies entirely on public charging infrastructure will not be as convenient as a gas car. To own a plug-in vehicle without charging at home, you'll have to be ok with the added inconvenience that comes with charging on-the-go full-time - something that will take up meaningful chunks of time. For this reason, you may want to consider a hybrid. We'll cover the various types of hybrids in our article, "Hybrid or Fully Electric: Which is right for me?".
You'll need to arrive at a range number that covers your daily needs on your busiest days (or alternatively, you'll need to be ok with adding a charging stop to that already-busy schedule). Keep in mind, your actual mileage need is not the amount of range you should be shopping for, you'll want to consider a number of other factors including...
If the answer is yes, the range number that you came up with in question 2 likely won't be enough for your needs when the temperate drops (or rises). If you live in a harsh climate, you'll want an EV that has as much as 50% more range than your actual mileage need.
If you're someone who will need to charge-on-the-go often, you may want to consider adding another 20% extra range above and beyond the factors we've already covered, so that the range you need on a regular basis is recouped faster at the plug.
If you intend to keep this EV long-term, you'll want to account for future battery degradation in your range needs. This can be difficult to predict, but assuming 10-15% range loss now will mean you're in better shape in a few year's time.
There are other factors that can affect how much range your car gets as well. Let's talk about a few of this now