in the place of the secondary storage device 68 a as shown by dotted lines in fig2 b however other locations of the secondary storage device 68 a are contemplated in other examples more than one secondary storage device 68 a is used in one example the solar roof kit 10 includes an electrical vehicle gauge 75 for observing the status of the battery pack 45 the gauge 75 includes a first controller not shown for calculating and storing a number of operating conditions of the electric vehicle 11 for later retrieval the first controller may include but is not limited to a microprocessor or a single board computer the gauge 75 calculates an amount of current being consumed by the motor 14 of the electric vehicle 11 and an amount of regenerative current being supplied to the battery pack 45 from the solar module 20 and the regenerative braking system 15 of the electric vehicle 11 based upon the voltages measured at the shunt 50 referring to fig3 the gauge 75 may include a visual display 77 connected to the computing device for displaying the operating conditions to an operator of the vehicle 11 in one example the visual display 77 is a graphical user interface including a first window 78 a second window 79 and a third window 80 the first window 78 may display an amount of power being consumed by the motor 14 the second window 79 may display an instantaneous voltage of.