Why Space-Based Solar Power Is Possible Now
Four challenges once made SBSP impossible: economics, technology, regulation, and safety. Here's how TerraSpark is solving all four.
TerraSpark argues that space-based solar power is now feasible due to a convergence of technological and economic advances. Launch costs have fallen from the Apollo-era's $85,000 per kilogram to under $1,700 per kilogram with Falcon Heavy. Mass manufacturing and in-space robotics replace costly astronaut assembly, driving costs 10 to 100 times lower.
Multiple wireless power transmission demonstrations validate the technology: in 2022, ESA with Airbus and EMROD beamed 2 kW of 5.8 GHz power across 36 metres; in 2024, Japan Space Systems transmitted microwave power over 5.5 km from an aircraft, setting a distance record; and in 2025, DARPA transmitted 800 W of laser power over 8.8 km. A Japanese in-space demonstration transmitting power from space to Earth for the first time is planned for 2026.
TerraSpark addresses regulatory concerns by noting that RF power transmission uses spectrum already governed by the International Telecommunications Union and national regulators. The RF power density at restricted-entry receiver sites is designed at 250 W/m2, one quarter of midday sunlight intensity, with spillover below the safe regulatory limit of 10 W/m2.