  In the framework of solid-state cooling technology, four kinds of caloric
effects, magnetocaloric (MC), electrocaloric (EC), barocaloric (BC) and
elastocaloric (eC) effects, are compared in view of environment discussion and
application fields. This field is primarily developed in the intention of
protecting the environment. However, some widely researched caloric materials
do not meet environmental friendly criteria. Currently, new caloric materials
(called "good" material) possessing the properties of friendly environment, low
cost, high caloric performance and practicability (low stress) need to be
found. In view of application, all current caloric effects/materials are
investigated for the common objective of cooling. However, the adapted
application cases for different caloric effects/materials are not considered.
Due to the different stimuli and different intrinsic properties (different
caloric performance for different dimensions) of caloric materials, they can
exhibit unique advantage to different application cases. "Good" caloric
material used for large-scale application is still less and deserve more
search. Purposeful research will save the cost and accelerate the
commercialization.
