The quantum state diffusion equation is applied to the problem of energy transfer in proteins. Lindblad operators, capable of coupling the full quantum Davydov-Scott monomer to a thermal bath, are derived. Numerical simulations with the QSD equation show that the Lindblad operators derived do recreate the exact equilibrium ensemble for the Davydov-Scott monomer. Comparison of the results obtained with the full quantum and with the semiclassical systems shows that, at biological temperatures, the latter provides a good approximation of the former.