Аннотация:The temperature dependence of the pyroelectric coefficient, γσ(T) for thermodynamically equilibrium pyroelectrics at T → 0 is found to follow the law γσ(T) ∝ Tn≥3 according to the Nernst theorem. At T < 1,5 K this excludes the γσ(T) values effective for technical applications. It is shown experimentally that this fundamental limitation is not realized in thermodynamically nonequilibrium polar media where γσ(T) = const is reached at T < 1.5 K.