Researchers from the California Institute of Technology alongside collaborators have demonstrated a breakthrough experiment: capturing energy in orbit and delivering it to Earth. The development, reported by Extremetech, marks a significant step in how solar power could someday travel from space to our cities without relying on weather or daylight.
The project centers on the Microwave Array for Power Delivery Low Orbit Experiment, known by its acronym MAPLE. This system converts sunlight into radio frequency energy and beams that energy down to a ground receiver. The concept hinges on two core capabilities: first, the generation of electrical power in a sunlit satellite environment with minimal interruptions; and second, an efficient, safe method to transmit that power through the atmosphere to Earth without excessive losses or interference. The experiment showcases a practical approach to space-based power generation and wireless power transfer, moving beyond theoretical proposals to concrete, measurable results.
Experts note that placing solar arrays in orbit offers distinct advantages. In space, panels can operate continuously, unshaded by clouds or the Earth’s rotation, yielding a more stable and potentially higher energy output. Yet the challenge of transmitting energy to the ground has remained a central hurdle. MAPLE has begun to address this bottleneck by demonstrating a controlled, directed energy link from orbit to a terrestrial station, providing valuable data on feasibility, efficiency, and safety for future, larger-scale deployments.
In the current test, MAPLE captures a modest amount of energy in space, with a portion reaching the ground. The figures cited describe energy capture in the range of a few hundred milliwatts per satellite during peak conditions, while the ground receiver receives a fraction of a milliwatt per session. While these numbers are not yet sufficient for everyday power needs, they establish a credible baseline for a constellation approach. Researchers envision deploying a fleet of satellites—akin to a network—designed to collectively supply power to a service area large enough to meet the energy demands of tens of thousands of households. The roadmap emphasizes scaling, reliability, and modular upgrades to move from an experimental demonstration to a practical infrastructure component.
Beyond MAPLE, the broader scientific effort continues to explore the behavior of electrons and energy transfer in novel media. Earlier investigations examined how charged particles move in liquids, revealing fundamental processes that influence how energy might be manipulated in future systems. These exploratory studies provide a deeper understanding of the physics at play, informing the design choices that help optimize conversion efficiency, beam stability, and safety for human environments on the ground. In this ongoing work, Caltech researchers and their partners remain focused on translating esoteric discoveries into real-world capabilities, always balancing technical ambition with practical safety considerations. (Extremetech)