Interplanetary Solar Energy Relay: Feasibility Analysis of a Mercury-Based Collection and Multi-Hop Distribution System

This paper presents a systems-level feasibility analysis of an interplanetary solar energy relay architecture in which solar radiation is collected at Mercury's orbital distance, converted to coherent laser radiation, and transmitted outward through a chain of autonomous relay stations to destinations throughout the solar system. Mercury receives a mean solar flux of 9,083 W/m², approximately 6.67 times the terrestrial solar constant, and possesses surface materials suitable for in-situ fabrication of photovoltaic arrays and structural components. We derive first-principles optical link budgets for diffraction-limited beam propagation at 1,064 nm wavelength, establish parametric trade spaces across transmitter aperture diameter (1 m to 10 km), relay spacing (0.1 to 2.0 AU), and receiver diameter, and compute capture fractions from the encircled energy of the Airy diffraction pattern. A hybrid relay architecture is proposed wherein inner-system hops employ high-reflectivity mirror relay with per-hop efficiencies of 85–90%, while longer hops employ full laser re-conversion at 21–58% per hop depending on technology maturity. Cumulative end-to-end efficiencies from Mercury to Venus, Earth, Mars, the asteroid belt, Jupiter, and Saturn are quantified under conservative, baseline, and advanced technology assumptions. A self-expanding collection architecture based on a 50-tonne seed factory with 12–18 month doubling times is shown to reach terawatt-scale collection within 20–25 years of initial deployment. Quantitative comparison with space nuclear fission, projected fusion, and local direct solar demonstrates that the Mercury relay architecture delivers orders-of-magnitude greater power to inner-system destinations using extensions of existing technology at Technology Readiness Levels 2–7, without requiring fundamental physics breakthroughs. Key technology gaps, beam safety considerations, and implications for solar system development are discussed.