[Paper Review] A Lightweight Space-based Solar Power Generation and Transmission Satellite

Behrooz Abiri, Manan Arya+18 more|arXiv (Cornell University)|Jun 16, 2022

Energy Harvesting in Wireless Networks20 citations

TL;DR

A modular, lightweight space-based solar power satellite design using tile units with parabolic concentrators, CMOS control, and a phased-array RF beam to Earth at 1–10 GHz, achieving 7–14% end-to-end efficiency and 160 g/m2 areal mass density with no moving parts.

ABSTRACT

We propose a novel design for a lightweight, high-performance space-based solar power array combined with power beaming capability for operation in geosynchronous orbit and transmission of power to Earth. We use a modular configuration of small, repeatable unit cells, called tiles, that each individually perform power collection, conversion, and transmission. Sunlight is collected via lightweight parabolic concentrators and converted to DC electric power with high efficiency III-V photovoltaics. Several CMOS integrated circuits within each tile generates and controls the phase of multiple independently-controlled microwave sources using the DC power. These sources are coupled to multiple radiating antennas which act as elements of a large phased array to beam the RF power to Earth. The power is sent to Earth at a frequency chosen in the range of 1-10 GHz and collected with ground-based rectennas at a local intensity no larger than ambient sunlight. We achieve significantly reduced mass compared to previous designs by taking advantage of solar concentration, current CMOS integrated circuit technology, and ultralight structural elements. Of note, the resulting satellite has no movable parts once it is fully deployed and all beam steering is done electronically. Our design is safe, scalable, and able to be deployed and tested with progressively larger configurations starting with a single unit cell that could fit on a cube satellite. The design reported on here has an areal mass density of 160 g/m2 and an end-to-end efficiency of 7-14%. We believe this is a significant step forward to the realization of space-based solar power, a concept once of science fiction.

Motivation & Objective

• Motivate and develop a lightweight, scalable space-based solar power architecture for geosynchronous orbit power beaming to Earth.
• Explore a modular, tile-based design that combines power collection, conversion, and transmission within repeatable units.
• Demonstrate that CMOS technology and ultralight structures enable a completely deployable, non-moving satellite with electronic beam steering.
• Assess end-to-end performance and mass density achievable with current or near-term technologies.

Proposed method

• Use a modular tile-based configuration where each tile collects sunlight with lightweight parabolic concentrators and converts it to DC via III-V photovoltaics.
• Implement multiple CMOS ICs per tile to generate and control phases of several independently-controlled microwave sources.
• Couple microwave sources to a radiating antenna array to form a large phased array that beams RF power to Earth.
• Transmit power to Earth in the 1–10 GHz range and collect at ground-based rectennas with intensity not exceeding ambient sunlight.
• Achieve areal mass density of 160 g/m2 and end-to-end efficiency of 7–14% through solar concentration, CMOS advances, and ultralight structures.

Experimental results

Research questions

• RQ1 Can a fully deployable, no-moving-parts space-based solar power system be realized using a tile-based modular approach?
• RQ2 What end-to-end efficiency and mass density can be achieved using current CMOS and lightweight materials for space-based solar power with RF beaming?
• RQ3 Is electronic beam steering via a phased array sufficient for reliable power transmission from GEO to Earth while maintaining safe ground-level intensities?
• RQ4 How scalable is the single-tile concept to larger configurations for practical power delivery to Earth?

Key findings

• The proposed satellite uses a modular tile design combining light-weight solar concentration, DC conversion, and RF transmission.
• Each tile houses CMOS circuits that control phase across multiple microwave sources feeding a large phased array.
• Power is beamed to Earth in the 1–10 GHz band with ground rectennas collecting power at ambient sunlight levels.
• The design achieves an areal mass density of 160 g/m2 and an end-to-end efficiency of 7–14%.
• The system is fully deployable with no moving parts after deployment and relies on electronic beam steering.