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A numerical study of the combustion of lean methane/air mixtures in a porous media burner is performed using a novelty geometry, cylindrical annular space. The combustion process takes place in the porous annular space located between two pipes, which are filled with alumina beads of 5.6 mm diameter (Al 2 O 3 ) forming a porosity of 0.4. The outer tube diameter of 3.82 cm is isolated; meanwhile the inner tube of 2 cm in diameter is covered by a continuous set of thermoelectric elements (TEE) for transforming heat energy into electricity. To achieve and maintain the proper temperature gradient on TEE, convective heat losses are considered from the TEE. The respective heat transfer coefficient is variable and is in the range 800 < h < 1500 [W / m 2 ]. The 2D mathematical model includes the energy equations for solid and gas phases, the momentum equations, the continuity equation, the fuel mass conservation, the perfect gas law and it is solved by Means of computational simulations in COMSOL Multiphysics. Computer simulations focus on the two-dimensional temperature analysis and displacement dynamics of the combustion front inside the reactor, depending on the values of the filtration velocity (0.1 < u g0 < 1.0, m/s) and the fuel equivalence ratio (0.06 < Φ < 0. The study shows that the cylindrical annular geometry can be used for converting the energy of combustion from lean gas mixtures into electricity, with a performance similar to the specified by manufacturers of TEEs. INTRODUCTIONThe need to lower emissions and increase efficiency in fossil fuel combustion has driven the search of new combustion methods and advanced burner designs. A porous media burner can provide a good solution due to a number of advantages compared to conventional free-flame combustion, such as large power variation range, high efficiency, compact structure with very high energy concentration per unit volume, extremely low CO and NO x emissions over a wide range of thermal loads, stable combustion over a wide range of equivalence ratios, 0.4 < Φ < 0.9 [1][2][3]. All the arguments mentioned above have driven the current development of these kinds of burners, which have already found several important industrial applications [4-