Google Heads to Space, Solves AI Power Shortage with Solar Energy... Unveils 'Suncatcher' [Tech Talk]

No Power Bottlenecks: Space Data Centers Beyond Earth
Self-Sustaining Power Generation with Satellite Solar Panels
Suncatcher Prototypes 1 and 2 Set for Launch in 2027

On December 1 (local time), Sundar Pichai, CEO of Google, unveiled the space data center research project "Suncatcher." Suncatcher is a "space data center" in the form of a satellite equipped with Google’s artificial intelligence (AI) semiconductor, the Tensor Processing Unit (TPU). It generates power using solar panels attached to the satellite, supplying the energy needed for AI training and inference independently. If the first and second prototypes succeed in operational tests two years from now, it is expected that the project could resolve the power supply issue, which is a major obstacle to expanding AI data centers.

Space Data Center Composed of Satellites

Satellite body and solar panels. Photo is not related to any specific expression in the article. Pixabay

At the beginning of this month, CEO Pichai announced via U.S. broadcasters such as Fox News and Google’s own website that Suncatcher has entered the research and development (R&D) phase. Prototypes 1 and 2, equipped with TPU computers, are scheduled to be launched aboard a rocket in 2027. Google plans to test these two satellites to assess the feasibility of the space data center, with the long-term goal of building a satellite network with a capacity of 1 gigawatt (GW).

The Suncatcher satellites generate electricity through solar panels connected to the satellite body. This electricity powers the TPU computers inside the satellites, as well as the satellite's own systems such as position control devices. Suncatcher will move to a "sun-synchronous orbit," a position where it can always receive solar energy most effectively, enabling stable power generation.

Suncatcher addresses one of the biggest bottlenecks in expanding AI data centers: power supply. Ground-based data centers require extensive power infrastructure, including power plants, energy storage systems (ESS), and transmission networks. In contrast, satellites can generate their own electricity, eliminating the need for such infrastructure. As long as satellites can continue to be launched, expansion can occur even faster than on the ground.

Major Challenges: Space Radiation, Launch Costs, and Communication

Laser-based space communication concept envisioned by the National Aeronautics and Space Administration (NASA). Google's Suncatcher project also utilizes laser communication as a core technology. NASA

Of course, there are many technical challenges that must be overcome for Suncatcher to succeed. Last month, Google published a "Google Research" report listing the prerequisite technologies needed to realize a space data center.

Suncatcher will connect thousands or even tens of thousands of satellites, treating them as a single massive data center. This requires software capable of simultaneously controlling a large number of satellites. Additionally, TPUs and high-bandwidth memory (HBM) that can withstand prolonged exposure to space radiation must be developed. Above all, the cost of launch vehicles to transport satellites into space must decrease. Google concluded, "Our internal analysis shows that if launch costs fall below $200 per kilogram by the mid-2030s, the operational costs of a space data center could be competitive with the annual operating costs of ground-based data centers."

The biggest current challenge is communication between satellites and between satellites and ground relay stations. Since the space data center relies on the collaboration of numerous satellites, it is essential to transfer data rapidly between satellites. Additionally, processed data must be sent back to Earth for practical use.

As a solution, Google is experimenting with "laser communication." This method transmits data via lasers to other satellites or ground relay stations, where the laser is then converted back into computer data. In particular, Google is researching "multiplexing," a technique that combines lasers of different wavelengths to boost data transmission speeds. In initial tests, laser multiplexing communication technology achieved a data transmission rate of 800 gigabits (Gb) per second. Currently, the interconnection networks of ground-based data centers typically operate at speeds of 400 to 800 Gb per second.

"Moonshot Projects Are a Google Tradition"

Waymo, Google's autonomous vehicle subsidiary. YouTube capture

Even if all these issues are resolved, it is still expected to be extremely difficult to simultaneously control thousands of satellites in Earth orbit. Google Research warned, "Fundamental physics problems and significant economic barriers remain," adding, "Thermal management of satellites and ensuring the long-term stability of satellites in orbit will continue to be challenges." Ultimately, the success of the Suncatcher prototype 1 and 2, scheduled for launch in 2027, will be crucial.

Nevertheless, Google appears firmly committed to advancing Suncatcher. The company emphasized, "Moonshot projects that tackle tough scientific and engineering problems are a long-standing Google tradition," adding, "Google has taken on countless challenges to realize technologies that remain uncharted, which led to the creation of large-scale quantum computers and the realization of autonomous vehicles."