P-V Curves

How does storing energy in the form of compressed air increase the efficiency of the system?

The answer is in the thermodynamics of the pressure and volume changes that are used by an engine to produce mechanical work.

In an internal combustion engine, the two high-pressure strokes of compression and power consume and produce energy. The compression stroke is negative work, or energy that the engine expends to do work on the gas. The power stroke is positive work, or energy that the expanding gases of combustion perform on the engine to create mechanical work.

The net energy produced by the engine (its efficiency) is the energy generated during the power stroke less the amount of energy consumed by the compression stroke. The areas inside the curves reflect the amount of energy used or generated during each cycle.

The net energy produced by the Scuderi Split-Cycle Engine is the difference between the two pressure-volume curves.

Whenever the engine is operating on compressed air stored in its air storage tank, the losses due to compression are reduced to nearly zero. The resulting efficiency of the engine under this mode of operation is essentially the total area of the power curve.

Compression Curve	Power Curve