This study deals with the assessment of the thermodynamic performance of co
ld thermal storage systems using exergy and energy analyses. Several cases
are considered, including some storages which are homogeneous, and others w
hich undergo phase changes. In some cases the storages are stratified. A fu
ll cycle of charging, storing and discharging is considered for each case.
Four cold thermal storage cases are presented in an illustrative example. T
he results demonstrate that. exergy analysis provides more realistic and ac
curate assessments of the efficiency and performance of cold thermal storag
e systems than those given by the more conventional energy analysis. In add
ition, exergy analysis is conceptually more direct since it treats cold as
a valuable commodity. It is concluded that the potential usefulness of exer
gy analysis in addressing and solving cold thermal storage problems is subs
tantial. Copyright (C) 1999 John Wiley & Sons, Ltd.