Large surface energy can be developed using highly porous Heterogeneous Lyophobic Systems (HLSs) which comprise a mesoporous solid and a non-wetting liquid to make working bodies. Such systems exhibit remarkable properties and characteristics such as high energy capacity, capability to simultaneously store (and restore) both thermal and mechanical energy during intrusion/extrusion of the liquid during compression/decompression operations. Usually an HLS is in the form of a suspension of a porous powder in the liquid. We have developed a P,V,T-calorimetry-volumetry system which can judicially be used to submit such suspension to compression/ decompression in a perfectly controlled thermodynamic way over extended T- and P-ranges. As a matter of fact, depending on the nature of the porous solid and of the non-wetting liquid it is always possible to find a high enough pressure to force the intrusion by compression of the liquid in the pores of the solid. The compression energy being store in the system can be further restored. We show how easily we can obtain the thermal and mechanical energies generated during repeated compression/decompression cycles while recording the associated P,V- diagrams.