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SpaceX begins testing first flightworthy Super Heavy booster
More than three months after the building-sized Starship booster’s latest return to Starbase’s orbital launch site, SpaceX has finally begun the process of testing what CEO Elon Musk says is still the first flightworthy Super Heavy.
After completing a number of pad tests in the days prior, SpaceX began filling Super Heavy Booster 4 (B4) with liquid nitrogen – supplied by the first orbital-class Starship launch – for the first time on December 17th. It’s unclear exactly what was done during the test but regardless of what transpired, the test and B4’s survival were a major, long-awaited milestone for both the Starship booster and the orbital launch site (OLS).
At this point in time, the general consensus among close followers of SpaceX’s Starship program is that the unprecedented amount of time it’s taken the company to complete Booster 4’s first test was not because of the rocket itself but rather because the orbital launch site needed to fully test it had yet to be completed. While it was SpaceX’s choice to not perform some kind of initial testing with B4 at one of the site’s two suborbital test and launch mounts, it’s clear that the company ultimately concluded that Super Heavy Booster 3’s successful July 2021 tests – including a cryogenic proof virtually identical to Booster 4’s first test – made such partial testing redundant.
Put a different way, SpaceX must already be confident enough in the quality of the first few Super Heavies rolling out of its Starbase factory to deem it unnecessary to verify the structural integrity of the first truly completed Super Heavy booster before putting the one and only orbital Starship launch site directly in the line of fire. Nonetheless, depending on how far Super Heavy Booster 4’s first cryogenic proof test went, it appears that SpaceX’s presumptions were correct.
On December 17th, SpaceX subjected Super Heavy B4 to a cryogenic proof test about twice as ambitious as B3’s, filling the booster maybe a sixth of the way with a few hundred tons of liquid nitrogen (LN2). What isn’t clear is if that test also raised the booster’s propellant tanks to flight pressures (6-8 bar or 90-115 psi). If Booster 4 did reach those pressures, the test is even more significant – partially proving that the rocket is ready for flight. On December 21st, SpaceX performed a similar series of cryogenic tests, again partially filling Booster 4 with about the same amount of liquid nitrogen but doing so two or three times in a row. Again, the Super Heavy survived the several-hour ordeal without any obvious issues. Still, a number of additional tests – some even more important – are still in front of SpaceX and Super Heavy B4.
The most obvious is simple enough: SpaceX needs to fully fill a Super Heavy booster for the first time. Depending on the storage situation, that process will likely begin by filling Booster 4 with about 2500 tons (5.5M lb) of liquid nitrogen (LN2) – about two-thirds full. If SpaceX also temporarily fills one of the orbital tank farm’s liquid oxygen (LOx) or methane (LCH4) tanks with nitrogen, it could fully load Booster 4 with around 3500 tons (7.7M lb) of nitrogen. At least according to SpaceX’s own website, that’s about the same weight as the propellant (3400t/7.5M lb) Super Heavy is designed to lift off with. If that full cryoproof goes well, SpaceX will then likely perform one or several wet dress rehearsals, ultimately filling Booster 4 with approximately 2900 tons (6.4M lb) of cryogenic oxygen and 500 tons (1.1M lb) of cryogenic methane.
Finally, SpaceX will probably kick off static fire testing, likely beginning by igniting just one or a few of Super Heavy’s many engines. Eventually, that process could culminate in the ignition of all 29 of Booster 4’s Raptors, briefly producing a bit less than 5400 tons (~11.9M lbf) of thrust – 50% more powerful than NASA’s retired Saturn V Moon rocket.
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According to Elon Musk, despite a number of recent signs and reports to the contrary, SpaceX still intends to fly Booster 4 and Ship 20 on Starship’s first orbital-velocity launch attempt, so the scope and scale of testing are only likely to grow over the next several weeks.
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Tesla finally got its Nevada Robotaxi Permit but with a few catches hard to miss
Nevada granted Tesla’s robotaxi permit, but capped the fleet at just ten vehicles for now.
Tesla has received its robotaxi permit in Nevada, more than two months after regulators closed the public comment period on the company’s application. News of the approval surfaced Wednesday night when Tesla investor and longtime company watcher Sawyer Merritt posted a copy of the interim order, and the Nevada Transportation Authority’s own carrier registry now lists the permit, AVNC Permit 002 under Docket 26-05015, as active for Tesla Robotaxi, LLC.
Tesla asked Nevada in June for authority to run up to 5,000 vehicles in Clark County within a year, however the permit the NTA issued is initially capping Tesla at ten fully autonomous vehicles and confines them to a defined geofence along the Las Vegas Strip corridor. Any expansion of that operating area, or any increase to the fleet size, requires the NTA’s approval first.
Tesla has received its Autonomous Vehicle Network Company permit in Nevada.
The Nevada Transportation Authority says that operations are limited to a maximum fleet of 10 fully autonomous vehicles and shall be conducted only within the Authority-approved Operational Design… https://t.co/Cxfd6GIfDk pic.twitter.com/iOO6wSZkHF
— Sawyer Merritt (@SawyerMerritt) August 13, 2026
The order also sets rules that look more restrictive than what Tesla runs in Austin. Rides are barred on roads with posted speed limits above 45 miles per hour, pickups are off limits within a quarter mile of Harry Reid International Airport without separate authorization, and every vehicle has to carry visible “Robotaxi” markings while notifying riders before each trip that no one is driving. The order also requires “appropriate human supervision”, language that suggests Nevada isn’t ready to let Tesla offer the rides without a safety monitor that it has run in parts of Austin since January. As with standard protocol with robotaxi services, Tesla must report any accident, system failure, or vehicle that becomes stranded on a Nevada road within five business days.
Tesla is entering a market Nevada already knows well. Zoox, the Amazon owned robotaxi company, has run its own autonomous vehicle permit in the state since last year, building up to roughly 100 vehicles and 350,000 rides along the Strip. That history likely explains why the NTA started Tesla at ten cars rather than the fleet size the company asked for. The agency has a template for scaling a permit up once a company proves out its safety record.
Tesla’s Nevada application first surfaced in June, when the company filed for the permit alongside plans for a maintenance hub in southwest Las Vegas. The company has said it won’t meaningfully scale its robotaxi fleet anywhere until FSD v15 ships, expected in late 2026 or early 2027, which makes the ten vehicle cap less of a constraint today than it might look on paper. For now, Tesla has the legal right to start Nevada rides. Whether it starts before FSD v15 arrives is a separate question the permit doesn’t answer.
Tesla Energy has introduced the Powerwall Lease in conjunction with Tesla Electric, making the service available in Texas. This new option delivers whole-home backup power using two Powerwall units for a net monthly cost of $35 after credits, accompanied by a low fixed electricity rate.
Under the lease terms, customers pay a one-time order fee of $100. The base lease payment for the two Powerwalls is approximately $122 per month during the first year, subject to a 3 percent annual escalator thereafter. Enrollment in a qualifying Tesla Electric Backup plan or Virtual Power Plant plan provides an $87 monthly credit.
Powerwall Lease is now available with Tesla Electric in Texas
Whole-home backup for $35/month, with a low fixed electricity rate
– Two Powerwalls, $0 installation
– Storm Watch outage protection
– One app to manage it all pic.twitter.com/oTzqc6K3aF— Tesla Energy (@teslaenergy) August 13, 2026
This credit lowers the effective cost to roughly $35 per month plus applicable tax.
Installation of the standard system carries no additional charge. The package features Storm Watch for outage protection and allows complete management through a single Tesla application. The system supplies continuous whole-home backup capability.
The Powerwall system enables households to maintain electricity during severe storms that disrupt the utility grid. When outages occur, the batteries automatically provide seamless backup power to the home.
Tesla announces 100k Powerwalls are participating in Virtual Power Plants
Tesla Storm Watch monitors weather forecasts and ensures the units are fully charged ahead of anticipated severe weather events so that power remains available throughout the disruption, keeping lights, refrigeration, and other essential systems operating without interruption.
Availability is restricted to select Texas locations where retail electric choice exists. Participants must lease exactly two Powerwall units and maintain continuous enrollment with Tesla Electric. Solar panels cannot be included under this particular lease arrangement.
The monthly credit activates automatically once the system is installed, receives permission to operate, and enrollment is confirmed. To retain the credit, customers are required to stay enrolled in Tesla Electric and fulfill all program conditions.
Nonstandard installations that involve electrical upgrades or special permitting may lead to extra expenses and might impact eligibility for the credit, so be sure to check with either your installer or Tesla to ensure you will still qualify.
Elon Musk continues to tease the unveiling event for the Tesla Roadster, a continuing trend that has grown into a bigger game of “When” for fans who have been waiting years for the car to finally enter production.
A video shared on X of the Joe Rogan Experience podcast that Musk appeared on last year, teasing the Roadster unveiling, was shared once again on the social media platform. The poster said the Roadster event will be “unforgettable.”
Musk agreed:
Yes
— Elon Musk (@elonmusk) August 12, 2026
The timing is interesting because just yesterday, Musk said that we will be getting flying cars, and for years, Tesla has hinted that it could develop a SpaceX cold gas thruster package that would help the car float or fly for a short period of time.
It would be reasonable to assume Tesla’s major delays with this unveiling event are likely caused by the company’s need to break the rules and push the envelope on nearly everything. Last July, Lars Moravy, Tesla’s VP of Vehicle Engineering, said:
“Roadster is definitely in development. We did talk about it last Sunday night. We are gearing up for a super cool demo. It’s going to be mind blowing. We showed Elon some cool demos last week of the tech we’ve been working on and he got a little excited.”
The latest updates that Tesla has given us are that the Roadster is in design development, and it did have several potential dates for an unveiling event this year, including April. It was then pushed to August.
However, there are no clues as to when Tesla will be ready, and fans are certainly getting frustrated with the delays.
For what it is worth, Franz von Holzhausen told Jay Leno this week that the event would be “very soon.”
We sure hope.
Tesla finally got its Nevada Robotaxi Permit but with a few catches hard to miss
Tesla launches Powerwall Lease for affordable home backup
