The Cost of Compressed Air
People tend to think of compressed air as just another utility, afterall you plug your tool into the socket, press the button and it operates. However, using compressed air as a motive force is extremely inefficient and thus extremely costly. The figure below illustrates the cost breakdown involved with a typical compressor over its lifetime.
The initial high capitol value of the compressor becomes relatively insignificant compared to the energy costs of the lifecycle of the compressor. The diagram below illustrates how much energy is wasted during the generation and distribution process.
As can clearly be seen, only a very small fraction of the total energy of generation is delivered. Some of this can be recovered relatively easily.