MPPT circuit solar charge controllers are considerably more elaborate than standard PWM solar power controllers. The voltage of the solar panel changes with the time of day and temperature. The optimum voltage for battery charging changes as the state of charge of the battery changes. The MPPT photovoltaic charge controller matches these voltages and can result in a 30% more efficient transfer of power. This means that FORTUNER MPPT solar charge controller can reduce the number of solar panels needed by up to 30% ­ a tremendous benefit. While only a small part of the system price, an MPPT solar panel charge controller can leverage the rest of the system for better performance.