A new generation of space companies is thinking bigger. From kilometers-wide orbital data centers to solar power stations requiring even larger structures in space, some of the most ambitious space businesses depend on building at a scale that’s never been attempted in orbit.
Modularity can help, and many massive systems in the works are designed to be assembled in orbit from smaller components launched in batches.
But when dealing with colossal structures, the fewer launches it takes to get a system in orbit, the more viable a business model becomes.
Many of these big-dreaming ventures are unsurprisingly rooting for SpaceX’s Starship, the largest rocket under development with a payload capacity of at least 100 metric tons to low Earth orbit (LEO).
Starship and other large rockets in the works will widen the kinds of businesses that make financial sense in orbit, according to leaders at Space Solar, a British startup with plans for gargantuan power stations that would revolutionize how the world meets its energy needs.
Merlin, the venture’s first power station slated for deployment around 2030, would span 400 meters — about the size of four football fields laid end to end — and beam 30 megawatts of microwave energy back to Earth from medium Earth orbit (MEO).
At 80 tons, it would weigh just one-fifth of the International Space Station, yet span four times the footprint of the largest human-made object in space.
And while 30 megawatts could power around 30,000 U.S. homes, this could be just the beginning.
“That’s essentially our minimum viable product for beaming commercial power,” Space Solar CEO Martin Soltau said. “Like with any new tech, the economics won’t be ideal, but they will be perfect for attracting Contracts for Difference from governments,” referring to a U.K. subsidy scheme supporting wind power on Earth.
Soltau said everything needed to assemble Merlin in space, including robots capable of autonomously building its structure in LEO and an orbital transfer system to reach its operational position in MEO, could fit entirely within a single Starship launch.
Space Solar’s satellites are designed to be hyper-modular, allowing for mass manufacturing practices that significantly reduce unit production costs.
By the mid-2030s, the startup hopes to deploy Kite, a 150-megawatt platform that’s twice the size of Merlin. It would use the same modular design and operate at the maximum allowable radio frequency power density from around 8,000 kilometers above Earth.
“It is going to be two Starships worth,” Soltau said.
Eventually, Space Solar hopes to build Eagle, a 1.4-kilometer-wide spacecraft in geostationary orbit that would beam 600 megawatts of continuous solar power to the ground. That mission would take eight Starship launches.
The venture hasn’t announced any launch contracts, and Soltau noted its modules could also fly on other heavy-lift rockets under development, such as Blue Origin’s New Glenn, which is “arguably more mature at the moment,” having already delivered a prototype payload to orbit.
Scaling up an old idea
Concepts for space-based solar power (SBSP) have been around for decades. NASA’s Solar Power Satellite reference system from the late 1970s, for instance, envisioned a non-modular structure measuring 10 kilometers that would be capable of generating five gigawatts of power.
However, SBSP ventures such as Space Solar argue that launch economics have only recently come within range of making this financially feasible.
Still, getting infrastructure to orbit is one of many challenges. The regulatory landscape for SBSP and the in-orbit assembly capabilities required are still in their infancy. Upfront costs also remain significant.
Space Solar estimates costs in the region of $400 million for main development, and a further $400 million in capital would be needed to fund Merlin.
“We do also have strong interest from energy clients in remote regions for a smaller system which would be around a quarter of the capital cost,” Soltau said. He pointed to dual-use military and commercial interest in spin-off applications, including in-space assembly of massive structures, power beaming and large lightweight in-space photovoltaic arrays.
He said Space Solar hopes successful ground tests will help encourage investors to back its ongoing $12.5 million seed round.
Turning solar power into a space-based utility is a tall order, but it’s exactly the kind of challenge a new generation of rockets is being built to meet.
This article first appeared in the May 2025 issue of SpaceNews Magazine with the title “Big ideas need big rockets.”
