Solar panel power output is directly affected by the temperature of the solar panel. Solar panels are made up of solar cells which convert light into electricity. Spacecrafts in geostationary orbits and low orbits experience temperatures in the range of -180ºC to 80ºC depending on the orbit. Solar cells are mounted on honeycomb panels which are installed and Sun pointed in on-orbit operation. Solar panels charge batteries and supply power to the satellite during sun-light period and batteries supply power during eclipse period. The open circuit voltage (Voc) of a silicon solar cell varies by about -2. 5 mV/ ºC and temperature can bring about a dramatic change in the solar cell characteristic, particularly with reference to operating voltage. PRT mounted on the rare of the solar panel measure the temperature of the solar panel. This sets up errors due to temperature rise between solar cell blanket and solar panel and slow temporary response of PRTs. A method of using solar cell capacitance to measure the temperature of solar cell blanket is proposed. This removes error due to location and transient response of PRT. Solar cell as a temperature sensor for measurement of temperature is demonstrated and the results compare satisfactorily with the reported results.

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