For anyone considering the move into electric car ownership, or for anyone who wants to understand their Tesla better, it’s crucial to get your head around how the power supply works. Not only does that mean getting to grips with the different types of chargers available, and their inherent pros and cons, but also in understanding just how much energy is necessary in order to go from empty to a full charge.
There is more to keep in mind when calculating this sum than you would first think, but, not to worry, everything you need to know about how many kWh it takes to charge a Tesla is wrapped up below.
CarBuzz has sourced all specs and stats directly from Tesla, unless specified elsewhere.
EV Energy Usage Explained
Tesla
What Is A Kilowatt?
Understanding energy for electric cars is quite different to understanding energy in a conventional gas-powered car, although, in many ways, also similar. A gas car will take onboard a gallon of fuel, and burn through it in exchange for miles. If the car can achieve 40 miles of range with that gallon of fuel, it can be rated at 40 miles per gallon – simple enough. Electric cars work in the same way, albeit with different metrics.
Instead of a 15-gallon fuel tank, an EV like a Tesla may have a battery size of 50 kWh, which means the battery can store up to 50-kilowatt hours worth of energy, or ‘fuel’. One kWh is enough electricity to supply 1,000 watts of power, for one hour – one example would be powering a 250-watt appliance for four hours. In a Tesla, those kWh are used to provide miles on the road. If, for example, a Tesla could achieve 40 miles per kWh, then that would be the efficiency rating.
How Much Does Electricity Cost?
Gas fuel is so well integrated into our everyday life, the costs are pretty well known. Statista currently provides $3.21 as the national average for how much a gallon of gas costs, while $3.60 is the cost for diesel. While that cost does fluctuate from one area to the next, it certainly doesn’t vary in the wild ways that electricity does.
Using data collected from Statista about the average cost of energy in each state, we calculated that the national average is $0.1716 per kWh. The cheapest area for electricity was in Utah, at just over 11 cents per kWh – the cost in Hawaii was almost exactly four times higher. The average provided of 17.16 cents is taken from all states.
Average Residential Electricity Costs – April 2024
State
Cents per kilowatt-hour
Hawaii
44.14
U.S. Average
17.16
Utah
11.01
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Charging A Tesla Takes More Energy Than You Would First Assume
There is an ideal scenario for charging an electric car, and it’s really quite simple. In theory, a 75-kWh battery from the 2024 Tesla Model 3 Long Range and Performance models should take 75 kWh of energy to charge, which would make the equation nice and simple to calculate. However, as ever, nothing is 100% efficient, and there are energy losses to factor in. Some energy will be lost through the cables, and as with all electrical uses, some energy will be lost due to heat generation.
The type of charger used to charge a Tesla will also have an impact on the amount of energy lost, as AC-DC power conversion will sap the power potential. For maximum efficiency, DC fast charging will be most effective, as this conversion does not need to happen. However, fast-charging all the time can dampen the longevity of a battery, which means the battery will be less efficient, and would need charging more often. There is rarely a win-win scenario when it comes down to which charger is best.
According to Inside EVs, the losses can be quite significant, although 10% can be considered a working average for energy losses through charging an electric car. This means, in order to calculate the amount of kWh required to charge a Tesla, an average energy loss of 10% needs to be factored in.
Related What do I need to know about installing an electric car charger in my home?
There are a wide range of options when it comes to electric car chargers for your home, but they all need a dedicated power source. You will need to have an electrician install either a 240-volt plug, like what’s used for your dryer, or hardwire the charger into your home. The cost can vary greatly depending on where you have the charger installed and the electrical setup in your home, so get several quotes to get the best price.
How Different Chargers Affect The Efficiency Of Charging A Tesla
Tesla
Different Charger Types
Supercharger: Up to 200 miles of range in 15 minutes Wall Connector: Up to 44 miles of range per hour of charge Destination Charging: Up to 44 miles of range per hour of charge Mobile Charging (240V): Up to 30 miles of range per hour of charge Mobile Charging (120V): Up to 3 miles of range per hour of charge
Tesla offers a wide choice of chargers to its customers, each providing a unique set of benefits and disadvantages. The most effective is Tesla’s Supercharger network. These fast chargers are hugely capable, and can provide up to 200 miles of charge in just 15 minutes – naturally, these are usually stationed in high traffic areas, such as in busy cities, or on the highways. Using these constantly can have a negative impact on the effectiveness of a car’s battery, and can cost more too, as the energy provided is often charged at a higher dollar-per-kWh cost than in a residential setting.
For this and other reasons, most customers will choose to charge their Tesla models at home, via a wall connector. This method provides up to 44 miles of charge per hour, and is not too damaging to the battery. It is also common for energy providers to charge less per kWh throughout the night, which is why it makes great sense to charge a Tesla overnight, at home. Destination charging is much the same, and can be found at workplaces and hotels.
Mobile charging is less effective, but certainly useful when no other option is available. Through a typical household outlet, only 3 miles of range per hour are added, although this jumps up to 30 miles of range per hour, if accessed via a 240V outlet.
Here’s How Much Energy It Takes To Charge A Tesla In 2024
Tesla
So, in order to calculate how many kilowatts it takes to charge a Tesla, the inefficiencies of charging have to be taken into account, which we will represent as an average of 10%. While many new models, such as the Tesla Model Y Juniper, are set to be released soon, we have used a range of only current 2024 models as examples. The calculation is relatively simple, and can be displayed as the total kWh required (battery capacity), multiplied by 1 + the efficiency loss percentage, or, in this instance, 1.10.
Using this method, we know that the amount of energy required to charge an entry-level Tesla Model 3’s 58-kWh battery is 63.8 kWh. As for how many kWh you’ll need to charge a Tesla Model Y Long Range, that works out to 89.1 kWh. Taking into account the most amount of energy lost is the Tesla Cybertruck (in Cyberbeast trim), wasting a total of 12.3 kWh in energy loss, in order to charge the 123-kWh battery pack. The different Tesla kWh capacity specs per model are listed below.
Estimated kWh Requirements To Charge 2024 Tesla Range From Empty To Full
Tesla Model
Battery Capacity
Amount Of kWh Required For A Full Charge
2024 Tesla Model 3 Rear-Wheel Drive
58 kWh
63.8 kWh
2024 Tesla Model Y Long Range
81 kWh
89.1 kWh
2024 Tesla Model S Plaid
100 kWh
110 kWh
2024 Tesla Cybertruck
123 kWh
135.3 kWh
Sources: Tesla, Inside EVs, Statista