A spectral radiometer system, measures incoming light intensity and spectral distribution in different wavelength-bands. An additional data storage device allows recording of the measured data. The inclusive sensor system yields very high sensitivity to incoming light. Furthermore, outstanding linearity of the detector response over several orders of magnitude of incoming light is achieved. Additional benefits are ultra low power consumption and minimum size. The sensor system can be used in remote solar radiation monitoring applications like mobile solar power units as well as in long-term environmental monitoring systems where high precision and low power consumption is a necessity.