Computed model solar chromospheres for prescribed departures from radiative equilibrium are specified in terms of the local mechanical (nonradiative) heat input. The computations are fully non-LTE and include millions of spectral lines. From the variety of models considered, the requirements on the heat input for a positive temperature gradient, dT/dh, in different layers of the chromosphere are discussed. The derived radiative cooling function for different models show that the cooling function is model-dependent. By comparing the computed models with the Vernazza, Avrett, and Loeser (1981) models, it is shown that the VAL-C model is characterized by a total heat flux 1.4 x 10 to the 7th ergs/sq cm/per sec, most of which is dissipated near the base of the temperature plateau. Half of the radiation loss is provided by Fe II, with Ca II, Mg II, and H playing important, but secondary, roles. CO molecules and H(-) are of lesser importance even near the temperature minimum, except in cases of minimal heating. 15 refs.