Adiabatic (isentropic) Storage
An adiabatic process is one where there is no heat transfer between the fluid and the surroundings: the system is insulated against heat transfer. If the process is furthermore internally reversible (smooth, slow and frictionless, to the ideal limit) then it will additionally be isentropic.
An adiabatic storage system does away with the intercooling during the compression process, and simply allows the gas to heat up during compression, and likewise to cool down during expansion. This is attractive, since the energy losses associated with the heat transfer are avoided, but the downside is that the storage vessel must be insulated against heat loss. It should also be mentioned that real compressors and turbines are not isentropic, but instead have an isentropic efficiency of around 85%, with the result that round-trip storage efficiency for adiabatic systems is also considerably less than perfect.
Famous quotes containing the word storage:
“Many of our houses, both public and private, with their almost innumerable apartments, their huge halls and their cellars for the storage of wines and other munitions of peace, appear to me extravagantly large for their inhabitants. They are so vast and magnificent that the latter seem to be only vermin which infest them.”
—Henry David Thoreau (18171862)