This article presents an architecture of hybrid micro power supply for wearable-pervasive sensor nodes. A lithium-ion button battery and a photo voltaic module with efficient power management circuitry are implemented as a miniaturised system. The performance was investigated in an office worker scenario with real-time power consumption measurments. It is shown that overall system efficiency in terms of battery life, low power dissipation and suitability for integration into a sensory system are highly improved. The measured power efficiencies in well-lit indoors and outdoors were reported to be in the range of 91-95%.