© 2015 IEEE. This paper presents simulation results on modeling hot electron effects with the energy balance model in unitraveling-carrier photodiodes (UTC-PD). The simulated heterostructure has an InGaAs absorption layer with gradual doping. Results are compared with reported experimental data. They demonstrate that the RF photoresponse obtained with energy balance model is closer to the measured bandwidth than with the drift-diffusion model which underestimates the performance of the UTC-PD. The results are shown at 0V and - 1V bias voltage on the device.