Condensation energy in the spin-fermion model for cuprates

We compute the condensation energy in the spin-fermion model using Scalapin o-White relation between the condensation energy and the change in the dyna mical structure factor in the normal and the superconducting states. We sho w that for parameters relevant to cuprates, the extra low-frequency spectra l weight associated with the resonance peak in the dynamical structure fact or in a superconductor is not compensated up to energies similar to J which are much larger than the superconducting gap Delta. We argue that in this situation, the condensation energy is large and well accounts for the data for cuprates.