China Conducts First Experiments for Space-Based Solar Power Plants

Why It Matters

Successful ground tests prove key components of space‑based solar power, a technology that could provide continuous, weather‑independent electricity and reshape global energy supply chains.

Key Takeaways

• 100 m wireless power transmission achieved with 20.8% efficiency
• 1,180 W delivered to stationary target; 143 W to moving drone
• 1.2 m phased‑array antenna steers microwave beam to 5.2 m rectenna
• System can power multiple moving targets from single transmitter
• Next milestone: in‑orbit tests to validate space‑based power generation

Pulse Analysis

China’s Sun Chasing project marks a tangible step toward the long‑held vision of space‑based solar power (SBSP). While the concept has been explored by the United States, Japan and the European Union, China’s recent ground‑based demonstrations differentiate it by achieving over 1 kW of transmitted power and maintaining beam stability on moving platforms. These milestones address two historic hurdles—efficient microwave conversion and dynamic target tracking—suggesting that the technology is moving from theoretical models to engineering reality.

The technical architecture combines a compact 1.2‑meter circular phased‑array transmitter with a 5.2‑meter rectenna receiver, delivering a reported 87% rectenna capture efficiency. By concentrating sunlight with spherical crown concentrators and converting it to microwaves, the system reaches a 20.8% end‑to‑end DC efficiency, a notable improvement over earlier prototypes that lingered below 15%. The ability to power a drone traveling at 30 km/h demonstrates real‑time beam steering, a prerequisite for future orbital stations that must serve multiple ground or aerial users simultaneously. Nonetheless, scaling the antenna size, managing thermal loads, and ensuring safe microwave exposure remain engineering challenges.

If China succeeds in launching an operational SBSP satellite, the impact on the energy market could be profound. Continuous, baseload power untethered from weather patterns would complement renewable grids, reduce reliance on fossil fuels, and enable high‑energy applications in remote or disaster‑affected regions. Moreover, the technology could support deep‑space missions by beaming power to spacecraft, reducing launch mass constraints. However, commercial deployment likely lies a decade away, pending successful in‑orbit tests, regulatory frameworks for microwave transmission, and cost‑effective manufacturing. The race to master SBSP underscores a strategic shift where nations view space not just as a frontier for exploration but as a potential cornerstone of future energy infrastructure.