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Tesla Semi truck’s battery pack and overall weight explored
The big question on everyone’s mind–at least on the minds of those who understand the freight transportation industry–is how much the Tesla Semi might weigh. If Tesla’s all-electric semi truck is to be competitive at all, it must be capable of carrying the same loads as current-use semi-trucks in the Class 8 field do.
A big point of contention from nay-sayers and those in the trucking industry who understand logistics was the lack of announcement of the Tesla Semi’s actual weight. Plenty of press was given to the much-touted “80,000-pound capacity” number bandied around by CEO Elon Musk during the truck’s unveiling late last year. That number, however, refers only to the gross vehicle weight (GVW) of the Tesla Semi and is, in fact, exactly the same number used by every Class 8 truck on the road. They’re called Class 8s, in fact, because the 8 refers to that 80,000-pound total vehicle capacity.
What wasn’t given by Tesla was the gross vehicle tare weight (GVTW) of the Semi. This is a far more important number. Where the GVW gives the total capacity of the truck in terms of how much its freight plus the truck itself can weigh, the GVTW gives just the weight of the truck, sans trailer and freight. This number tells logistics experts how much actual freight and trailer the truck can haul legally.
For example, a typical “day cab” configuration 18-wheeler with a diesel engine weighs roughly 32,000 pounds with a relatively lightweight box trailer attached and full fuel tanks. That leaves about 48,000 pounds of freight capacity for the truck. That’s important because, although the truck won’t be loaded to capacity every time, it will be expected to be capable of carrying up to about that weight. Most big rigs on the road are capable of hauling 44,000 or more pounds worth of freight, depending on configuration and trailer type.
Having experience with driving commercial trucks in the past, once hauling a refrigerated trailer that had a freight capacity of 44,500 pounds, I learned that some industries count on freight capacity as part of their logistics costs and will literally fill a truck to its maximum in order to minimize those costs.
In logistics, weight and total freight capacity are highly important metrics in the overall scheme.
What We Know
Thinking about that, then, let’s look at what we know of the Tesla Semi and its potential weight. We know that the truck uses four independent electric motors that are derived from the Model 3, that it has an energy consumption of less than 2 kWh per mile, and that it can be charged to up to 400 miles in about half an hour. We also know that Elon promised 300 to 500 miles of range in total. On that latter point, it’s pretty clear that a “lower range, cheaper option” will be offered as has been done with most of Tesla’s vehicles to-date. So we can assume a 300-mile version and a 500-mile version will be forthcoming for the Semi.
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We also know that the Tesla Semi had eight ports in its charging plug array. We saw this at the unveil in some close-up photos.
It’s clear to us that even if the Tesla Semi isn’t to become a big player in the trucking industry, the idea behind it will change things forever.
What We Don’t Know
What we don’t know is whether Musk and Co have something up their sleeves for the batteries. Much of the speculation regarding the Tesla Semi has been in regards to Tesla Semi’s massive battery pack.
In actuality, having a huge battery breakthrough on a vehicle like the Tesla Semi would not necessarily be a good thing for business. If there is a huge breakthrough, then all bets are off and most of our speculation in this article is moot. That would, however, mean that the sales potential of the Semi would be far lower than it would be otherwise because one thing that logistics companies and fleet managers aren’t interested in are flashy new, breakthrough, and (most importantly) untested, unproven technologies.
To a fleet manager, those phrases mean “breaks often, expensive to fix” and the potential positives will be ignored because of that. No one who wants to keep a job as a fleet manager or logistics purchaser will gamble on something unproven. Like new battery technology for a truck whose primary cost will be in its batteries. Likewise, unless there is a clear benefit in some terms other than pure business (like marketing or potential tax breaks), no board of directors will risk shareholder wrath on new tech either.
Close-up look at Tesla Semi’s drivetrain from underneath
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We can say, as a side note, that most of the orders that have been placed for the Tesla Semi thus far are from corporations and companies who are doing business in areas where the marketing bonanza and potential tax incentives for laying down those relatively low-cost deposits are immense. Most of the companies involved have already invested heavily (and very publicly) in alternative fuel options outside of Tesla over the past few years. We also note the timing of both the Tesla Semi’s announcement (and order-taking) and the before-2018 rush by potential customers to put in deposits.
We reiterate that our not knowing if Tesla has some kind of big battery breakthrough announcement is a big “if” in our analysis here.
What People Smarter Than Us Have Said
Some people who know more than we do about things like math and engineering science have crunched the numbers on the Tesla Semi’s battery potentials. Over at Engineering.com, John Ewbank broke the results down into layman format. Here’s the gist.
If the Tesla Semi uses 2 kWh to travel a mile, then a 500-mile range means 1,000 kWh of power. That is not the actual size of the battery, though, as the charging requirement would preclude a huge pack.
In order to get 400 miles in thirty minutes of charging, Ewbank notes, the charger would have to be 1.6MW to achieve the 800kWh of promised charge in only 30 minutes. Charging at that rate is not possible because the result would be arching in the pack, which would surely be akin to the next Boring Company Flamethrower meme when Semi trucks begin to explode in flames during charging as a regular event. So the charging has to be split up.
Tesla Semi Megacharger port could support 1 MW of power.
The answer is simple, of course, and may explain the strange layout of the eight-port charging hub shown on the Semi at its unveil: there are four battery packs.
Instead of one big pack, four smaller packs (one for each motor, even) are used and are thus charging separately from one another, but simultaneously. Based on Tesla Semi’s Megacharger port configuration, this would likely mean that four of them are positive sides and the other four are grounds. Allowing for a single, huge wire to be plugged into each. The controls for the charging system interface may be plugged in separately (perhaps the oval-shaped black thing to the side?).
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What This Adds Up To
We add up that bit of information plus what we know about the truck and get an estimated weight. Using the current weight of a Tesla Model S battery pack at 540kg per 90 kWh, we can do some simple math to estimate the Semi’s batteries would weigh about 6,000 kg. We aren’t sure about the new battery weights for the upcoming battery updates, but we can assume a 10-15 percent reduction from several factors (storage density, improvements in chemistry, packaging lightening) without being too aggressive or overly optimistic. Going with the fifteen percent reduction, that 6,000 kg drops to 5,100 kg. That’s about 11,244 pounds.
A conventional tractor, as we’ve said, has a tare weight of around 32,000 pounds when fully fueled and with a lightweight box trailer in place. Remove the trailer and the truck itself is about 22,500 pounds. It’s difficult to then go to just the weight of the powertrain components and fuel, but they’re considerably less than 11,000 pounds in all.
Tesla Semi spotted doing a tire-shredding acceleration run down in the wild
Looking at the shipping weight for a crated engine and transmission for a Class 8 truck, we can see that they weigh about 8,000 pounds on average. Add in fuel and other components and another 1,500 pounds (at most) are put on the truck. We then assume that the rest of the truck (framing, braking systems, air compressor, etc) are about the same for the Tesla Semi in order for it to meet Class 8 standards. So we call those a wash.
That means that the Semi, under our estimates, is roughly two tons heavier than would be a standard day cab big truck in the Class 8 category. This means the Semi would be that much less capable in terms of freight hauling that’s offset by its unprecedented all-electric performance. That amount, however, is probably not enough to stop the primary buyers of a day cab truck like this from balking at a purchase. The weight difference alone would be repaid in potential fuel savings, tax incentives, green marketing, and maintenance costs.
The trouble will come with cost differences. If the ROI is not there, most logistics buyers won’t write any purchase orders. But at least we can say that as far as we can tell, the weight differences of the Tesla Semi alone aren’t going to be a huge bar against entry into the trucking industry.
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Elon Musk has declared that SpaceX has effectively solved one of Starship’s most persistent engineering challenges: the reliability of its heat shield tiles.
During the company’s first-ever Earnings Call, the SpaceX CEO stated:
“I don’t want to jinx it or anything, but I think I would call the heat shield problem solved at this point. All indications from data and visual inspection is we have solved it. That doesn’t mean we won’t make improvements, but we do not see any technical obstacles to achieving rapid reusability at this point.”
Starship’s heat shield consists of roughly 18,000 hexagonal ceramic tiles covering the windward side of the upper stage. These tiles form the thermal protection system that shields the vehicle’s stainless-steel structure from the extreme heat of atmospheric reentry.
Elon says he believes the heat shield problem with Starship is currently solved.
He called it “arguably the single biggest problem” pic.twitter.com/eEE9vM5zlz
— TESLARATI (@Teslarati) August 4, 2026
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During descent, atmospheric friction generates temperatures exceeding several thousand degrees Celsius and creates plasma flows capable of melting unprotected metal. The tiles absorb, radiate, and insulate against this energy, allowing the vehicle to survive and potentially fly again. Without a durable heat shield, full and rapid reusability, the cornerstone of Starship’s design for frequent launches, satellite deployments, and deep-space missions, would remain impossible.
The tiles have long been a source of difficulty. On earlier test flights, a significant number of tiles detached during ascent due to vibration, aerodynamic loads, and imperfect attachment methods using pins and adhesives. Gaps between tiles allowed hot plasma to infiltrate, causing secondary damage and hot spots on the underlying structure.
These issues echoed challenges faced by NASA’s Space Shuttle, whose ceramic tiles required extensive, labor-intensive inspections and replacements between missions, preventing rapid turnaround. SpaceX has iteratively improved materials, standardized tile shapes, refined attachment techniques, added secondary ablative layers, and tested sealing methods such as “crunch wrap” felt to close gaps.
Progress was visible across Flights 10–12, with steadily better tile retention, yet questions remained about whether the system could support the minimal-refurbishment goal of rapid reuse.
Flight 13 on July 24 provided the decisive evidence. Ship 40 flew a deliberately more demanding profile with higher dynamic pressure to stress the heat shield beyond typical operational loads. It successfully deployed 20 operational Starlink V3 satellites, the first such payload on a Starship mission, performed an in-space Raptor engine relight, and executed a controlled reentry.
Elon Musk sheds two new bits of detail on Starship after 13th test launch
Cameras on six of the satellites and onboard sensors captured extensive imagery and data of the shield throughout the flight. The ship then achieved its softest splashdown to date in the Indian Ocean, remaining intact and floating rather than breaking apart or exploding as on prior missions. This allowed drone inspections and continuous telemetry of the heat shield in near-real time.
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Post-flight analysis showed the majority of tiles remaining attached with only minor damage and limited plasma streaking at seams. Musk noted that the mission delivered “all the heat shield data we needed and then some.” Combined with visual inspections, these results underpinned his subsequent assessment that the core technical barriers to rapid reusability have been cleared. While refinements will continue, Flight 13 marked a pivotal step toward Starship’s operational future.
SpaceX COO Gwynne Shotwell outlined ambitious plans for Starlink Mobile during the company’s August 4 Earnings call, signaling a direct challenge to U.S. wireless giants like AT&T, T-Mobile, and Verizon.
Shotwell noted that the three companies generate roughly $600 billion in combined annual revenue. “I anticipate us to be able to acquire quite a few of their customers because I think our service will be better,” she said. “We will eliminate dead zones leveraging the satellites in orbit. It will be better during any natural disaster… I’m quite excited about Starlink Mobile.”
SpaceX President & COO Gwynne Shotwell on @Starlink Mobile and its impact on Verizon, AT&T and T-Mobile:
“Roughly, between them, $600 billion a year. I anticipate us to be able to acquire quite a few of their customers. Our service will be better. We will eliminate dead zones… pic.twitter.com/UYZUkrGc0L
— Sawyer Merritt (@SawyerMerritt) August 4, 2026
SpaceX intends to combine its satellite constellation with terrestrial infrastructure. The company has acquired about 65 MHz of spectrum from EchoStar and plans to deploy next-generation Starlink Mobile satellites in 2027, with upgraded service targeted for the end of that year.
Shotwell described the enhanced network, leveraging more satellites and spectrum, as potentially “100 times better” than the current direct-to-cell offering, which already supports basic texting and app-based voice/video in coverage gaps through partnerships. She also indicated plans for low-cost cellular base stations that could integrate with existing Starlink dishes, creating a hybrid system for broader capacity in urban, suburban, and rural areas.
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For the general public, Starlink Mobile promises significant advantages. Satellite connectivity can fill gaps where traditional cell towers fail, delivering service in remote locations, mountains, or during outages caused by storms, wildfires, or infrastructure damage—conditions in which ground networks often collapse.
Users could enjoy more consistent coverage without relying solely on dense tower builds, potentially at competitive prices as SpaceX scales. The hybrid approach aims to support full mobile services, including higher-speed data, while working with unmodified smartphones over time.
These developments revive long-standing but unfounded rumors of a Musk-developed “Tesla phone.” Speculative claims of a “Pi Phone” or similar device with built-in Starlink connectivity have circulated for years on social media, often featuring fabricated images and details. Elon Musk has repeatedly denied any such plans, stating Tesla has no intention of entering the smartphone market unless forced by extreme circumstances with app stores.
No official product, filings, or development announcements have ever materialized; the rumors remain hoaxes.
The announcement quickly pressured telecom stocks. Shares of AT&T, Verizon, and T-Mobile fell between roughly 2 and 4 percent in after-hours and premarket trading as investors weighed the competitive threat from a hybrid satellite-terrestrial network.
While execution challenges remain—spectrum deployment, infrastructure rollout, and regulatory hurdles—Shotwell’s remarks mark SpaceX’s clearest signal yet of entering the consumer mobile market as a full competitor.
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Venture capitalist Chamath Palihapitiya has cautioned investors shorting SpaceX shares, drawing a direct parallel to the intense short-selling pressure Tesla faced in its early public years.
Responding to reports of elevated short interest in the newly public rocket, satellite, and AI company, Palihapitiya noted that similar dynamics played out with Tesla, where aggressive short sellers ultimately “went broke.”
SpaceX (NASDAQ: SPCX) went public on June 12, 2026, in the largest IPO on record, pricing at $135 per share. Shares quickly surged to an all-time high of $225.64 just days later, briefly implying a valuation exceeding $2 trillion. The stock has since retreated sharply amid valuation concerns, lockup expiration fears, and broader market dynamics.
By early August, it traded near $108–$125, representing a roughly 50 percent decline from the peak and bringing the market capitalization closer to the $1.5–1.7 trillion range. On August 4, shares closed up more than 9 percent at $125.33 ahead of earnings before facing pressure in after-hours and premarket trading.
Short interest has climbed dramatically. According to S3 Partners data widely cited in market reports, short positions reached approximately 219.3 million shares by late July, about 34 percent of the limited public float of roughly 640 million shares, and represented a notional value of around $24.6 billion.
Utilization of shares available to borrow hit 95 percent, with borrow fees rising. This level of shorting exceeded the dollar value of short bets against Tesla at the time and built rapidly ahead of two catalysts: the company’s first post-IPO earnings and an August 6 lockup expiration that could free up to 911.5 million additional shares.
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CEO Elon Musk has issued warnings of his own. In mid-July, as short interest approached one-third of the float, he posted that “the survival probability of firms who maintain a significant short position in SpaceX over time is very low,” reiterating his view that the company could ultimately be worth more than Earth if it achieves its goals.
On August 4, just before earnings, Musk responded to the latest short-interest data by saying, “I try to warn them, but they just double down.”
SpaceX delivered its first quarterly results as a public company after the close on August 4. Second-quarter revenue rose 92 percent year-over-year to $7.8 billion, beating consensus estimates near $6.8–6.9 billion.
The net loss narrowed to $541 million, or 9 cents per share, better than the roughly 23–24 cent loss expected. Starlink/connectivity contributed about $4.3 billion (up 66 percent), while the AI business generated $2.6 billion (up roughly 250 percent). Capital expenditures were heavy at $18.4 billion, largely tied to AI infrastructure. Management projected a $100 billion annualized revenue run rate by year-end 2026 and outlined a path toward $1 trillion in annual revenue by 2030.
The combination of Chamath’s historical reminder, Musk’s repeated alerts, and the company’s ambitious growth targets underscores the high-stakes debate surrounding SPCX. Short sellers are positioned for near-term supply pressure from the lockup, while long-term bulls point to Starlink scale, Starship progress, and AI compute expansion as reasons the bears may ultimately face the same fate as many early Tesla skeptics.
SpaceX has solved Starship’s biggest challenge, Elon Musk says
SpaceX is coming for wireless giants with Starlink Mobile
