  The work presented in this article describes thermoelectric effect in hollow
blocks for heat waste harvesting purposes. The study consists of developing a
numerical model formed by a heat transfer equation coupled to thermoelectric
effects equations to study thermoelectric generators(TEG) incorporated inside
Lebanese hollow blocks through two simulations using finite difference scheme
and using finite element scheme. Results showed a voltage of 5.85mV produced
from a single 8.6 x 0.4 x 0.4 cm3 thermoelectric leg made of Bismuth Antimony
Telluride for {\Delta}T=30K. A design with 3 TEGs incorporated inside a hollow
block was tested and validated numerically using both methods, the main results
obtained for {\Delta}T=30K, showed a voltage {\Delta}V=0.72V, a current I=0.06
A and a figure of merit ZT=0.55. The design was then optimized for economic
purposes.
