This work aims to present the current state of simulations of
electroluminescence (EL) produced in gas-based detectors with special interest
for NEXT --- Neutrino Experiment with a Xenon TPC. NEXT is a neutrinoless
double beta decay experiment, thus needs outstanding energy resolution which
can be achieved by using electroluminescence. The process of light production
is reviewed and properties such as EL yield and associated fluctuations,
excitation and electroluminescence efficiencies, and energy resolution, are
calculated. An EL production region with a 5 mm width gap between two infinite
parallel planes is considered, where a uniform electric field is produced. The
pressure and temperature considered are 10 bar and 293 K, respectively. The
results show that, even for low values of VUV photon detection efficiency, good
energy resolution can be achieved: below 0.4 % (FWHM) at Qββ​=2.458
MeV