Abstract: Apparatus and system for purging hot air from the cabin of vehicles when parked under hot sun conditions. The system employs a solar panel of relatively smaller size suited for incorporation with a sun roof or rear window of the vehicle. A power transfer regulator is utilized which is responsive to the peak voltage chacteristic of the solar panel to cause the panel to substantially continuously to perform at its peak power output capability. As such, an equivalent power at lower voltage and enhanced current levels is submitted to the electric drive motor of an air purging fan within the vehicle. Switching controls are provided which monitor the state of the vehicle's internal combustion engine through its ignition switch and which provide turn-on of the purging system at such time as vehicle cabin temperatures reach predetermined levels. When the air circulation system is disabled, the solar panel is employed for charging the battery of the vehicle.

Abstract: A circuit for operation with solar panels exhibiting constant current and variable voltage characteristics. The power output of the panels is maximized by the circuit through the use of a step-down form of regulator which functions to monitor the peak voltage level of the panel and regulate with a switching type regulator in accordance therewith. Thus, peak voltage levels are maintained while current output to the load driven by the panels is enhanced. When employed for battery charging, the circuit includes a threshold selection network which identifies the nominal voltage rating of the battery under charge and provides appropriate adjustments to carry out a pulse charging technique. For start-up conditions wherein battery voltages may be below levels requisite to evaluate nominal rated voltages, a higher level charging voltage is applied for a predetermined short interval until adequate threshold is achieved to make appropriate determinations of rated voltage values.

Abstract: An alternate energy interface control for implementation with utility derived power sources and alternate power sources such as are provided by solar panels, windmills, and the like employed with systems utilizing storage batteries. The system monitors the current level of photovoltaic solar panels within intervals during such panels are connected with the battery storage source and further monitors the voltage levels developed by such panels during normal open circuit conditions thereof. A logic control is provided which monitors alternate source currents and voltage as well as storage battery voltage levels to prioritize the use of available alternate energy sources. Battery charging during periods of alternate power source availability is with a pulsed technique to enhance battery lifespans.