How much does it cost to charge a Tesla Model 3 with solar? We’ll break down the averages with fairly simple math and figure it out. We’ll also compare how much you would spend to charge a Tesla 3 without solar through SoCal Edison.
If you’re looking for mathematical breakdowns, this article is for you. The first problem we need to solve for is how many additional solar panels you’ll need.
There are two Tesla 3 models:
- A standard 50 kWh battery with a 220-mile range
- A long-range 70 kWh battery with a 310-mile range
Let’s go with the bigger battery for our example.
According to the U.S. Department of Transportation, the average American drives 13,476 miles per year, or 1,123 miles per month.
So, if you drive an average of 1,123 miles per month and the Tesla 3 with the long-range battery can drive 310 miles on a single charge, let’s find out how many full charges you’ll need per month.
1,123 / 310 = 3.6 charges per month
Allowing some wiggle room for battery degradation over time and other variables, let’s put it at an even 4 charges per month.
70 kWh battery x 4 charges per month = 280 kWh needed per month
To break it down by day:
280 kWh per month / 30 days in a month = 9.3 kWh needed per day
How many solar panels to charge a Tesla 3 battery every month?
How many kWh a solar panel produces varies partly according to how much sun it gets. Depending on where you live, that can average across the U.S. between 4 and 6 hours a day. We’ll split the difference and say 5 hours.
9.3 kWh per day / 5 hours of sun per day = 1.86 kW to meet energy needs
Let’s divide that by 78 percent to account for the slight loss during power conversion.
1.86 kW / .78 = 2.38 kW
Now we simply divide the kilowatts you need by the solar panel power rating to get the average number of solar panels you’ll need. Most residential solar panels are 250 W.
2.38 kW / .25 kW = 9.52 solar panels
Rounding up, that’s roughly 10 additional solar panels needed to charge the Tesla 3 with the long-range battery.
How Much Does a Single Solar Panel Cost?
The average cost for residential solar panels is around $3.30 per Watt installed.
If you need 10 x 250 Watt solar panels to charge your Tesla 3, the total wattage you’ll need to charge it is 2500 Watts.
2500 W x $3.30 = $8250
If you qualify for the 30 percent ITC tax credit, this will reduce to $5,775.
Once you have paid for those panels, they will keep on generating electricity to charge your Tesla 3 ad infinitum (most solar systems are warranted for 25 years).
No costly trips to the gas pump ever again.
How Much Would it Cost to Charge Tesla 3 with SoCal Edison?
The average kWh of energy used by a household every month in the U.S. is 897 kWh. So we’ll add that plus the extra 280 kWh per month you’ll need to charge your Tesla 3.
897 kWh + 280 kWh = 1177 kWh per month
With SoCal Edison’s current pricing structure, you would fall under Tier 2 and pay $0.25 per kWh.
Your average monthly electricity bill through SoCal Edison without solar would be:
1177 kWh x .25 = $294.25 per month
Zeroing in on how much you would spend per month only on charging your Tesla 3 under Tier 2 prices:
280 kWh x .25 = $70 extra per month
Pay Yourself Back with Solar Panels to Charge the Tesla 3
If you use solar panels to charge your Tesla 3, you would pay yourself back for that $5775 investment in about six to seven years.
$5775 for the extra solar panels / $70 per month = 82.5 months
If you’re under time-of-use rates through SoCal Edison, your rates could vary between $0.12 per kWh during off-peak times and $0.48 per kWh during peak times.
Even with solar, there will likely be times when you’ll have to switch to grid power. Charging your Tesla EV (Electric Vehicle) during off-peak hours is a good strategy to take advantage of lower pricing.
How much you drive, which panels you select and how much sun you get will all affect the costs of charging your Tesla 3. All in all, your added electricity consumption from a Tesla 3 can be offset by solar production, leading to significant savings over time.
If you’d like to learn more, here’s another article on charging EVs with solar.
Our energy advisors are always up for a solar math chat if you want to dig deeper into the numbers for your unique situation. Shoot them an email them at firstname.lastname@example.org.