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Does Tesla’s New Electric Semi Truck Make Sense?

Does Tesla’s New Electric Semi Truck Make Sense?

Adding to its electric-vehicle fleet, Tesla unveiled its new Semi truck designed for cargo hauling across the country. While an impressive feat, is it a practical next step in the evolution of EVs?

Some would say it was only matter of time until Tesla started to think bigger. Apparently, they meant “literally.” Last week, alongside with announcements for a new Space X rocket and a new roadster, Tesla’s CEO Elon Musk rolled its brand new  Semi truck design on to the stage. The Semi truck, of course, is completely electric, and is designed to replace the fuel-powered cargo trucks of today.

The new Tesla Semi truck is a streamlined design for the purposes of achieving the lowest-possible drag coefficient. The truck in theory will be more power-efficient than any diesel truck on the market today.

The Semi truck does not skimp on performance. It can accelerate from 0 to 60 mph in five seconds without tow. A diesel truck requires 15 seconds for the same acceleration. And when towing the legally allowed weight of 80,000 lbs., it can accelerate from 0 to 60 mph in just 20 seconds. The truck has a max speed of 65 mph when climbing a 5% grade, compared to a diesel truck that can only achieve 45 mph on the same climb. The range of the truck is 500 miles. According to Musk, 80% of today’s truck routes are less than 250 miles.

To help efficiency, the truck has an extremely low drag coefficient. The Tesla Semi’s drag coefficient of 0.36 is lower than today’s trucks at 0.65 to 0.7, and even lower than the Bugatti Chiron at 0.38, one of the world’s fastest sports cars. The windows are made out of Tesla’s Armor Glass, which are guaranteed to be indestructible. Trucks with window cracks are illegal to drive, so this innovation offers a large potential savings for drivers. The streamlined look of the Semi is a byproduct of the battery pack being mounted under the floor of the cab. The two rear axles have electric motors attached on either side, making for a total of four. This design gives the truck a lower center of gravity.

The cabin is specifically designed for single drivers. It is easier to get in and out of the cabin with the ability to stand fully when inside the cab, and the driver is centered in the cab relative to the road. There is a removable jump seat for a passenger located offset and behind the main driver position.

What About Charging?

The logical question is how one charges the truck. To support the new fleet, Tesla is installing an updated network of its Tesla Megachargers across the country. Legally, truck drivers are required to take a 30-minute break for every six hours. Roughly, six hours of driving would result in about 400 miles at the Semi’s top speed. Tesla claims that with the new Megachargers, the truck can achieve a full recharge within the 30-minute rest window.

The Megachargers have an estimated 1.6-MW charging capability, which is 10 times stronger than the current Superchargers. The solar-powered Megacharger stations would be open 24/7. Battery details were not disclosed, but according to, if Tesla claims <2 kWh per mile, the battery capacity is roughly 1,000 kWh. This would be a breakthrough in battery-capacity design. In addition, the trucks will also have regenerative braking, which will help offset electric charging dependency.

Saving Cost via Drafting

The cost of operation is where Tesla’s Semi will make or break the design. At the unveil event, Musk remarked that the operating cost of the truck would be $1.26 per mile. That beats the current $1.51 per mile operating cost for diesel trucks.

Musk also stated that the cost savings would be greater when trucks would drive in convoy. By using drafting techniques, where the first truck creates a block and helps the trucks behind it achieve better aerodynamics, the potential savings have the power to be less expensive than even rail transportation costs.

The drafting technique will rely on Tesla’s autopilot and tracking technology. The “Enhanced Autopilot Features” will be standard in every truck. This adds a level of safety by preventing accidents when the driver has a medical condition or falls asleep at the wheel. Also, in regards to added safety, the torque is adjusted manually on each wheel via independent motors, making jackknifing impossible.

The battery is located under the cabin, and every wheel has its own independent motor. The truck will be equipped with safety features such as automated enhanced driving, which will act as a safety measure and be used in convoy transportation.

Companies have already shown interest in the Tesla Semi. Walmart has committed to purchasing a fleet of 15 to test their functionality. A statement from Walmart expresses how it has had a history of implementing new technology. “We have a long history of testing new technology—including alternative-fuel trucks… we believe we can learn how this technology performs within our supply chain, as well as how it could help us meet some of our long-term sustainability goals, such as lowering emissions.” Other companies like JB Hunt and Canada’s Loblaw grocery chain have also placed down payments on their own Tesla trucks.

The Verdict is…

So the real question is this a logical conclusion of the electric-vehicle future? My answer is maybe. In theory, and according to the numbers stated by Mr. Musk, the idea seems great. Zero emissions, solar-power charging stations, and a more efficient mode of transportation—it all adds up to a win.

But Tesla has been in the news lately regarding production problems, losing as much money last quarter as they did in all of 2016. Many engineers will also quickly point out the harm in creating lithium-ion batteries in the size required by the Tesla Semi, and how that from cradle to grave, the environmental benefits may be a zero sum. Also, there is no study on how these trucks will behave in traffic. Even with regenerative braking, the performance reality has yet to be determined. Like everything else Musk does, this is a definite wait-and-see if it will work.

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