If you’re about to get an electric vehicle and are concerned about getting your EV charging situation sorted out at home without getting seriously charged — as in digging a big hole in your wallet — you’re reading the right post.
I’ll explain, via my own experience, how to get your new vehicle’s “tank” filled and avoid those over-the-top electrical upgrade estimates.
While I wrote this based mostly on my two-plus years of experience with my 2021 Model Y Long Range, most of what I’m mentioning here applies to any EV. It’s collective wisdom from my large group of friends and neighbors with different EV types.
To cut to the chase: Getting your car charged is generally more straightforward than you might think, and it’s much better than going to a gas station. If you live in a home with a garage (that has an electrical outlet) or an accessible outdoor socket, you’re already ready to leap. Think of your EV as another large appliance.
But there’s more to getting a car charged than plugging it in. Let’s start with the simple math of charging a vehicle.
EV charging: The general math of getting a car charged
Charging a battery is like filling a tank with water (or liquid.)
The tank is the battery, and the water flow (pressure + pipe size) is the incoming electricity determined by Ampere (A) and Voltage (V). Combining the two, we have Wattage (W), which is, in this case, the tank’s volume or the flow of power.
Getting a bit nerdy: Voltage vs Ampere vs Wattage
It’s easier to understand electricity if you think of it as the water flowing through a pipe from one container to another.
- Voltage (V): The force that pushes the electricity (water pressure.)
- Ampere (A): The size of the flow (the result of pipe size + pressure.)
- Wattage (W): The load or capacity (of the size of the containers at either end follow, or the capacity of the flow at any given time.)
The higher the amperes and voltage, the faster electricity can move from one place to another (charging speed). The more wattage, the more power is stored, used, or delivered.
Here’s the relationship between these three:
V * A = W
You generally find wattage in two measurements:
- Kilowattage (kW): It’s the metric way to call 1000W. It generally indicates the rate of electricity.
- Kilowatt-hour (kWh): The energy consumed, delivered, or accumulated over one hour. It indicates the amount of energy.
A car’s battery is measured in kWh. The higher the number, the more energy it can hold.
When the flow is constant, the rate of water going into the receiving tank is the same. So, how long it takes to fill a tank depends on its size.
My Tesla Model Y 2021’s battery has a capacity of 75 kWh. Per the EPA estimate — which is massively exaggerated — the car has a range of up to 324 miles on a full charge or 4.3 miles per kWh. With that, when plugged into a 120V (which caps at 15 A) socket, its charge rate is 5 miles per hour.
The real-world distance you can drive per kWh varies greatly depending on speed, load, wind, terrain, your belief in Elon Musk’s nonsense, and so on. What is always true is the rate electricity flows into the battery, which, in this case, is about 1.5 kWh (give or take).
The point is this: You can increase this charging rate by using higher amps (and voltage). That’s the case for all EVs.
Typically you need a 240V socket if you want more than 15A. And, in the US, that means you need to do some serious electrical upgrades.
Or do you?
EV charging: It’s different from the pump
More than two years ago, in preparation for my Model Y’s arrival, I had difficulty figuring out our electricity situation at home.
I’m sure many of you are feeling the same right now when anticipating the delivery of your beloved vehicle.
Doing my search and listening to the advice of online EV “experts” — there are lots of them these days — I got quotes from reputable electricians that range between $5,000 to $15,000 in electrical wiring and breaker upgrades, depending on the scope of the work.
It’s “all about the amps,” they told me, and it made sense. As mentioned above, the standard 120V socket in the US can push out a maximum real-world rate of 15 amps — often lower for safety reasons.
And that’s all true — we need higher amps to deliver faster charging, which generally requires better wiring and breaker upgrades. The electricians didn’t lie.
But in hindsight, it was only because I was looking at the whole thing from the mindset of a person who had always driven a car with an internal combustion engine (ICE). And so did the electricians. None of those giving me the quotes had an EV.
The real question is this: How fast do you need to charge?
EV charging vs filling the gas tank: You’ve got all night
With an ICE car, we “feel the pain at the pump,” as they often say during high gas prizes. And since we don’t (want to) spend much time there, it’s great that the tank only needs a few minutes to fill up.
And then what? You drive the car home, put it in the garage, and there it sits, doing nothing for hours.
With an EV, on the other hand, you can get the tank filled (slowly) whenever you’re home or even when the car is not driven. So, in most cases, fast charging is unnecessary, at least for daily usage. You literally have got all night.
Take my Model Y, for example. If I plug it in the 120V socket when I get home at 5 PM, by 8 AM the next day, it’s obtained enough juice for some additional 60 real-world miles. And that’s enough for the day’s driving. And on the days I don’t drive, I can keep the car plugged in much longer.
So again, if you have a garage with a 120V socket or one that you can plug outdoors, you’re ready to get an EV as far as charging is concerned. But, sure, a faster charging option doesn’t hurt — among other things, it gives us more flexibility.
But how fast is fast?
Check out the three current charging levels below and I’ll talk about how I managed to get my fast-charging solution (for the Model Y) without going overboard and spending thousands of dollars I didn’t have.
EV charging levels (1, 2, and 3) in brief
These tabs contain brief info on the three current EV charging levels.
Level 1 EV Charging: 120V (up to ≈ 15 A)
- Electricity: Alternating current (AC).
- Connectors: J1772, Tesla.
- Charging rate: 3 to 5 Miles Per Hour (≈ 1.5 kW).
- Applicability: Home or anywhere with a 120V wall socket.
Charging level 1 is the lowest and, in the US, generally means you plug the car directly into a 120V outlet.
Most EVs come with a portable charger for Level 1 sharing. But you can also get a third-party charger. The charger is simply a glorified power cable — the charging function is inside the car.
Until April 17, 2022, Tesla has included the Mobile Connector with its cars. It’s the company’s default Level 1 Charger.
Level 2 EV Charging: Up to 240 V (up to ≈ 80 A)
- Electricity: Alternating current (AC).
- Connectors: J1772, Tesla.
- Charging rate: Up to 80 Miles per Hour (≈ 20 kW).
- Applicability: Home or anywhere with a 240V wall socket or a charging station.
Level 2 sharing is the fastest option you can install at home. It requires new wiring. At the minimum, in the US, you’ll need a new breaker for a 24V outlet.
If you want to get a charging station, such as the Tesla Wall Charger, new wiring is required. This type of charger must be wired directly into a 240V breaker and won’t work with any socket.
Level 2 can deliver between 15 A to 80 A of electrical flow and can give an EV up to 80 miles in an hour of charging — most of the time, 60 miles is the norm.
Level 3 EV Charging: At least 400 V
- Electricity: Direct current (DC).
- Connectors: Combined Charging System (CCS) and Tesla
- Charging rate: at least 3 miles per minute, up to over a thousand miles per hour.
- Applicability: Public charging station
Level 3 charging equals “gas stations” for EVs — it’s the fastest charging option.
In the US, most, if not all, non-Tesla Level-3 charging stations use the CCS connector, which encompasses the J1772 connector.
Level 3 charging uses direct current (DC) instead of alternating current (AC), like in the case of Levels 1 and 2. Each charger costs tens of thousands of dollars. That’s not to mention the electricity cost.
As you might have noted, all charging options require a to-car connector — the part that goes into your EV’s charging port.
In the US, there are two main charging connection standards:
- Tesla proprietary: Supports all three levels of charging using alternating current (AC) or direct current (DC).
- Combined Charging System (CCS): Supports charging level 3 via DC but has built-in support for the AC-only J1772 standard for Level-2 and Level-1 charging.
Only the Tesla connector can fit Tesla cars. For this reason, a converter is needed if you want to get your Tesla juiced up at a non-Tesla charging station. Currently, there are two converters in the US, the J1772-to-Tesla and CCS-to-Telsa.
CCS vs J1772
A car with a CSS charging port supports both J1772 and CCS connectors.
Tesla owners take note: If you have the CCS adapter, you don’t need the J1772 adapter anymore.
When or if Tesla opens its charging network to non-Tesla EVs in the US, you’ll also find converters for the other way around.
Simple home charging options
For home charging, most EVs come with a portable “charger.”
This charger is simply a glorified power adapter — the actual charger is inside the vehicle. For this reason, you can always buy a third-party portable charger. They all function as power cords. I’ll use the Mobile Connector as an example, but other portable charger shares a similar concept.
Though much bigger, the Mobile Connector is similar to a laptop’s power adapter — it can handle power outlets from 110V to 240V and various amps outputs via different to-wall adapters.
The design allows users to change the to-wall end to fit different socket types. And by default, the charger includes the standard adapter head for the region.
In the US, that adapter head is the NEMA 5-15, the three-prong plug for any wall socket around your home. In this case, you can plug it right in, just like a phone, and it will charge the car a few miles per hour, as mentioned above.
Using different adapter heads out of the bundle in the above picture, you can charge the car at faster rates, depending on the power output of the fitting socket.
In the US, the best option is the NEMA14-50 — a popular plug for electric ovens or dryers. With it, the Mobile Connector works with a 240V outlet to draw up to 32 amps of power to deliver a filling rate of around 7kWh. (For my Model Y, that’s about 30 miles per hour.)
The actual amps the car’s charger draws depend on the real-time condition when you plug it in, and users generally have control over that. With a Tesla, you can use the mobile app to make the car draw lower amps than available.
So a 240V Level-2 charging option will also allow you to trickle charge the car when you’re not in a hurry.
A typical home charging station
In my case, I decided not to do any breaker upgrade for a wall charger.
Instead, I had an electrician friend install a 40-amp NEMA 14-50 240V outlet with a separate breaker and use the NEMA 14-50 adapter head for my Mobile Connector. All that cost less than $600.
I later got a second Mobile Connector, mounted it in the garage as my home charging station, and kept the original with the car.
My fast-charging port can deliver up to 32 amps and fill my model Y at around 30 miles per hour.
However, most of the time, I tune that down to 20 amps to charge more slowly — there’s no need to put an unnecessary strain on the wiring. Once in a while, I still plug my car into the 120V socket. It has always been enough for my needs anyway.
EVs and energy usage
EVs are considered large appliances in terms of power consumption and should be plugged in as such. Specifically, you shouldn’t charge your car at home during peak hours. Instead, charge them at night when, among other things, the cost of electricity is lower.
For this reason, a 240V charging port gives you more options regarding when to charge the car.
So my routine has been to plug the car in and let it do its things when I get home. And I generally set the max charge at 180 miles (about 55% of the battery’s capacity.)
And that brings us to some tips on charging your EV.
EV charging tips
Generally, batteries are at their best when they are not empty or completely full.
For EVs, it’s recommended to keep the battery level between 20% and 80% because:
- You can charge it the fastest. It takes much shorter to fill a battery from 20% to 80% than from 80% to 100%.
- It outputs energy the most efficiently.
- The battery itself can last the longest without degrading.
This idea of giving stuff some “breathing room” exists in ICE cars, too. Most gas stations suggest that you don’t “top off” the tank, and all mechanics will tell you that letting the car run completely out of gas is a bad idea. Getting stranded aside and emptying the gas tank means you will let the harmful sediments into the engine.
So unless you’re about to drive on a long trip, never charge your EV over 90%. And when you drive it, plan to get it charged before the battery gets lower than 20%.
Don’t drive your EV until its battery is completely depleted. Unless ICE car, EVs need its juice to keep its subsystem running.
Finally, it’s best to monitor your car’s battery using percentages than miles. The range estimate is greatly inaccurate and widely exaggerated — especially in Tesla’s case — that it’s dangerous to count on. But if you use it, discount at least 30% to be safe.
Be aware of charging schemes
When using a charging station, pick one that bills you by energy, not by how long the car is plugged in. The latter can be ridiculously expensive.
While many venues come with free charging stations, which is great because you’d need to park your car anyway, other places put up time-based low-energy chargers to get high “parking” fees from EV drivers.
The point is, make sure you read the sign or do the math.
Tesla Supercharger
It’s impossible to talk about EV charging without mentioning Tesla’s Level-3 Supercharger network, the most comprehensive charging network worldwide.
In fact, the only reason I get the Model Y (or any Tesla) is because of the company’s Superchargers. They make talking road trips possible — two things worth noting about Tesla’s supercharging network.
First, it’s ubiquitous and super convenient to use:
- When the car’s battery is low, its map will show nearby Supercharging stations.
- Punch in a destination on your car, and the car’s navigation will include charging station(s) if need be.
- When you pick a charging station, the car automatically optimizes its battery for fast charging.
Drive the car to a charging station, plug the charging cord into the car, and you’re all set.
You can manage the charging (and payment) via the car’s touchscreen or the app. But if you don’t do anything, the vehicle will be charged at your predetermined level, or the level enough for the next leg of a long road trip.
Secondly, a Supercharger station can charge a car fast. Starting at 70kW and can go as high as 250kW, a station can fill my Model Y’s battery from 20% to 80% in between 30 minutes and 5 minutes, respectively.
Tesla also has Destination Chargers as low as 15kW, similar to home chargers that top at around 60 miles per hour. Most non-Tesla charging stations charge at this rate, too.
Supercharger and cost
The actual price varies from area to area, but generally, the cost to fill my Model Y from 20% to 80% is about $20 — that’s easily over 100 miles worth of energy.
On average, on a long road trip, I paid around $18 each time I used a Supercharger. Note that the company charges idle fees — you need to remove your car when the charging is done.
EV charging: The takeaway
There you go. If you have a wall socket and maybe a long extension cord, chances are your home is ready for an EV. There’s no need to get fancy with electricity.
Give your new driving experience some time, and you’ll find out if you need a Level-2 charger or not, and even then, you won’t need to spend much.
The key here is to know that you don’t have to charge at a super fast speed at all times and every single time — there’s no point in that when you’d leave the car sitting by itself all night anyway — and you can always take your vehicle to a Level-3 charging station when need be.