Solarwheel design, build and install a stand alone power supply in Khazakstan. In this picture the air was -33C. The system relays data 3 kms using a long range WiMax wifi link. The design brief was very exacting due to the extreme ambient temperature range. In Summer +30C, and winter down to -40C. The objective : Provide a year round power supply for a data monitoring station, including cabinet heating and ventialtion. Average power consumption 80 to 100 watts at 24volts. Successful commissioning completed in January 2016.