Measurement of heat flux and energy deposition on the divertor target plates is an essential issue for safety of the plasma facing components and also for the validation of models describing transport of particles and energy in the scrape of layer. In JET, a high time resolution InfraRed (IR) system and several embedded ThermoCouples (TC) 10mm below the tile surface are used to measure the surface and bulk temperatures of the target plates respectively. Time resolved estimates of the heat flux density and energy are computed with the 2D code THEODOR constrained by the IR temperature measurements. The total energy load to the tile is derived from the temperature evolution measured by the thermocouples. This paper reports on analysis of the inner and outer peak heat flux density and energy asymmetries during L-mode power staircase discharges using both IR and TC data with an emphasis on the important question of divertor power asymmetry changes when operating with forward (FWD-B) and reversed toroidal magnetic field (REV-B).