  Using a semiclassical Boltzmann transport equation (BTE) approach, we derive
analytical expressions for electric and thermoelectric transport coefficients
of graphene in the presence and absence of a magnetic field. Scattering due to
acoustic phonons, charged impurities and vacancies are considered in the model.
Seebeck ($S_{xx}$) and Nernst ($N$) coefficients have been evaluated as
functions of carrier density, temperature, scatterer concentration, magnetic
field and induced band gap, and the results are compared with experimental
data. $S_{xx}$ is an odd function of Fermi energy while $N$ is an even
function, as observed in experiments. The peaks of both coefficients are found
to increase with decreasing scatterer concentration and increasing temperature.
Furthermore, opening a band gap decreases $N$ but increases $S_{xx}$. Applying
a magnetic field introduces an asymmetry in the variation of $S_{xx}$ with
Fermi energy across the Dirac point. The formalism is more accurate and
computationally efficient than the conventional Green's function approach used
to model transport coefficients and can be used to explore transport properties
of other exotic materials.
