Abstract: The study describes the main features of the development of a hybrid power supply for wireless sensor node using alternative energy sources. The concept of a hybrid power supply is based on the presence of energy in various forms like vibration, optical or radio frequency energy. The study discuses a block diagram of the hybrid power supply that includes a power control integrated circuit, a micro-energy cell, a piezoelectric vibrating energy harvester, a solar panel, a RF-DC energy harvester, a microcontroller. The study shows the characteristics and waveforms of the power supply that depend on the control signals from the microprocessor and on the charge cell micro-energy cell from the energy harvester. The study also describes the usage of micro-energy cells for harvested energy storage.