 This paper discusses the relationship between lattice thermal conductivity, CAP-L, electrical conductivity, sigma, total thermal conductivity, total, and electronic component of thermal conductivity, CAP-E. The Weidmann-Fron's law is used to estimate CAP-E from sigma measurements, but significant deviations from the degenerate limit occur for non-degenerate semiconductors. A first-order correction to the degenerate limit of L can be based on the measured thermal power, absolute value of C-beck coefficient S, independent of temperature or doping. The equation L equals 1.5 plus EXP-0.7S is proposed as a satisfactory approximation for L, which is accurate within 5% for single parabolic band slash acoustic phonon scattering assumption and within 20% for PBC, PBS, PBT, C0.8G0.2. Using this equation for L instead of a constant value will significantly improve the estimation of lattice thermal conductivity when detailed band structure and scattering mechanism is not known. This article was authored by Hyunsik Kim, Zachary M. Gibbs, Englutang, and others. We are article.tv. Links in the description below.