Why are efficient compressors and turbines important in gas-turbine engines?

Efficient compressors and turbines are critical to the performance of gas-turbine engines because they directly dictate the system's thermal efficiency and net power output.

In a standard cycle, the turbine must generate enough power to drive the compressor before any useful work can be extracted for a generator or thrust. If these components are inefficient, the turbine must produce significantly more total power just to compensate for the compressor's energy demands, which drastically reduces the engine's overall efficiency. For instance, if component efficiency drops to 80 percent, the thermal efficiency of a system can plummet from 48 percent to roughly 25.9 percent.12

Historically, the challenge of designing efficient compressors was a primary obstacle in the development of gas-turbine technology. Modern engineering has overcome this by achieving high efficiency levels—typically 86–88 percent for compressors and 88–90 percent for turbines—allowing for the high-performance operation seen in contemporary jet engines and power systems.1