Fuel supply is a bottleneck for Starship—here’s how SpaceX will get around it

If SpaceX is going to fly Starships as often as it wants to, it's going to take more than rockets and launch pads.

First, there's the sprawling factory that SpaceX has constructed at its Starbase location along the Gulf Coast in South Texas. The building, known as Starfactory, is designed to produce one Starship per day. A couple of miles to the east, SpaceX has built one Starship launch pad and is preparing to activate a second one.

With Starship, SpaceX seeks to buck the old way of doing things. Tanker trucks have traditionally delivered rocket propellant to launch pads at America's busiest spaceports in Florida and California. SpaceX has used the same method of bringing propellant for the first several years of operations at Starbase.

But a reusable Starship's scale dwarfs that of other rockets. It stands more than 400 feet tall, with a capacity for more than a million gallons of super-cold liquid methane and liquid oxygen propellants. SpaceX also uses large quantities of liquid nitrogen to chill and purge the propellant loading system for Starship.

It's not just Starship's size. SpaceX has the green light from the Federal Aviation Administration to launch Starships up to 25 times per year from South Texas, and is seeking regulatory approval to fly up to 120 times from new launch pads on Florida's Space Coast. Eventually, SpaceX eyes daily launches of Starship, or even more, as the company deploys a fleet of ships traveling to low-Earth orbit, the Moon, and Mars.

There are innumerable bottlenecks to achieving such a fast launch cadence. One of them is simply a matter of logistics. It takes more than 200 tanker trucks traveling from distant refineries to deliver all of the methane, liquid oxygen, and liquid nitrogen for a Starship launch. SpaceX officials recognize this is not an efficient means of conveying these commodities to the launch pad. It takes time, emits pollution, and clogs roadways. The sole two-lane highway leading to Starbase from nearby Brownsville, Texas, is riddled with potholes and cracks in the pavement from overuse by heavy trucks.

On-site, out of mind

SpaceX's solution to some of these problems is to build its own plants to generate cryogenic fluids. The company recently received approval from local authorities to build an air separation plant across the highway just north of the Starbase launch pads. Construction of the plant began this summer. Once operational, this facility will take in air, condense it, and separate it into oxygen and nitrogen. The resulting liquid oxygen and liquid nitrogen will flow about 1,000 feet through a pipeline into ground storage tanks at the launch site.

But the air separation plant will only partially solve the propellant bottleneck. SpaceX still needs methane to fuel the 39 (eventually 42) Raptor engines that power the rocket's Super Heavy booster and Starship upper stage. The answer to this problem is a pair of methane liquefaction facilities to convert natural gas—initially delivered by truck or a future pipeline—into pure liquid methane, and eventually, a methane generation plant co-located with Starbase's dual launch pads.

SpaceX has flirted with the idea of propellant generation plants at Starbase before, but this is the closest the company has come to making it a reality. A public notice released by the US Army Corps of Engineers on August 27 describes SpaceX's plans, and an accompanying map illustrates the changes coming to the Starbase launch site.

The corps is seeking public comments on SpaceX's proposals. The corps says SpaceX's proposed expansion covers approximately 21 acres, including 18 acres of undeveloped "emergent wetlands" and "wind-tidal flats" about a quarter-mile inland from the beach.

The expansion would also include new storage areas for propellant and ground equipment, staging pads, internal roadways, and a new security wall around the southern perimeter of the launch site.