Page "BCS theory" Paragraph 21

* Due to the energy gap, the specific heat of the superconductor is suppressed strongly ( exponentially ) at low temperatures, there being no thermal excitations left.

However, before reaching the transition temperature, the specific heat of the superconductor becomes even higher than that of the normal conductor ( measured immediately above the transition ) and the ratio of these two values is found to be universally given by 2. 5.