Though there's still more than two months left to 2020, that hasn't stopped Tesla (TSLA 3.91%) analysts from trying to start making estimates on the electric-car maker's potential growth in 2021. During the company's third-quarter earnings call last week, an analyst took a stab at getting CEO Elon Musk to talk about vehicle delivery expectations for next year -- and he succeeded.

As it turns out, Tesla may be positioned for massive growth in vehicle deliveries in 2021 -- and the automaker has the installed production capacity to back it up.

Tesla vehicle production

Vehicle production at Tesla's factory in Fremont, California. Image source: The Motley Fool.

Tesla deliveries may skyrocket

After explaining how he arrived at his estimate, New Street Research analyst Pierre Ferragu he believed Tesla could deliver between 840,000 to one million cars in 2021 -- up from the projected 500,000 units the company is expected to deliver this year.

When asked whether he was on the right track, Musk responded saying, "I mean, it's in that vicinity. Yes. You're not far off."

To put this potential growth into perspective, consider it in percentage terms compared to the 500,000 vehicles Tesla is aiming to deliver this year. Growing deliveries from 500,000 in 2020 to 850,000 in 2021 implies 70% year over year growth. One million deliveries next year, of course, would translate to 100% growth (again assuming Tesla delivers 500,000 vehicles in 2020.

How Tesla's deliveries could grow 70%

But are these realistic expectations?

There's actually a rational case for this analyst's projections. As the analyst pointed out when explaining the reasoning for his forecast, the automaker has already installed enough production capacity to produce nearly 850,000 cars per year.

Tesla broke down this capacity in its third-quarter shareholder letter. The company's production lines at its Fremont, California factory can produce 90,0000 combined Model S and X units per year and 500,000 combined Model 3 and Y units. Tesla's new Shanghai factory has the capacity for 250,000 Model 3 vehicles annually.

Meanwhile, Tesla's Model Y factories in both Berlin, Germany and Austin, Texas are both under construction. In addition, the company is building a production line for Model Y in Shanghai. Given Tesla's recent accelerated pace at bringing factories and new production lines online, it wouldn't be surprising to see production at these factories begin in meaningful volumes next year.

While Tesla could run into some unexpected detours, the company's recent execution and its expansion plans suggest Tesla will likely see accelerated growth next year.