Hydration energy is one component in the quantitative analysis of solvation.
[1] The value of hydration energies is one of the most challenging aspects of structural prediction.
The trade-off of these interactions vs those within the crystalline solid comprises the hydration energy.
If the hydration energy is greater than the lattice energy, then the enthalpy of solution is negative (heat is released), otherwise it is positive (heat is absorbed).
For instance, water warms when treated with CaCl2 (anhydrous calcium chloride) as a consequence of the large heat of hydration.