  We present thermoelectric properties of Be$_2$C monolayer based on density
functional theory and semi-classical Boltzmann transport theory. Electronic
structure calculations predict this material as a semiconductor with a direct
bandgap of 2.0 eV computed using Gaussian-attenuating Perdew-Burke-Ernzerhof
(Gau-PBE) hybrid functional. The Gau-PBE band structure is used to compute
transport properties by solving the Boltzmann transport equation under the
constant relaxation time approximation. In this work, we have explicitly
determined the relaxation time by studying the electron-phonon interactions in
the system to estimate absolute transport coefficients. Our results show that
the monolayer possesses a high power factor ($\sim$ 3.44 mW/mK$^2$ @300K),
similar to the commercial TE materials doped-Bi$_2$Te$_3$ and PbTe, suggesting
that Be$_2$C monolayer is a promising thermoelectric material.
