Technology Readiness Level

Technology Readiness Level (TRL) is a standardized scale, originally developed by NASA, used to assess the maturity of a technology. The scale runs from TRL 1 (basic principles observed and reported) to TRL 9 (actual system proven in mission operations). TRL assessments are used by space agencies, governments, and investors to evaluate how close a technology is to deployment. For SBSP, different component subsystems sit at very different TRL levels. Individual rectenna elements and basic phased array antennas may be at TRL 5 or higher. A complete SBSP system — integrating solar collection, power conversion, high-power phased array beaming, atmospheric propagation, and large-scale rectenna reception — has not been demonstrated and would not be considered high TRL as a system. TRL assessments must be component-specific, not system-level generalizations, to be meaningful.