An Answerable Question
@DWFields, your question is an answerable one--I just have not done the calculations. However, safety is also an issue. An equivalent amount of energy stored in liquid air (I do not like this phrase, see below) is probably safer than that stored in steam. A catastrophic release of liquid air will not be as dangerous as a similar release of steam or liquid CO2 for that matter.
Actually the energy is being removed from the liquid air and being deposited in the gaseous air at the compressing station--so there is already waste heat at the compressor site but maybe not as high in quality as that from an industrial site. Creating a colder heat sink for the engine is really all that is going on here.
