Wireless power transmission to downhole well installations is provided using acoustic guided Lamb waves and a tubular conduit (production tubing, casing) as the power transmission medium. A phased array of acoustic transmitters is present at the transmitting end (surface) and an array of acoustic receivers at the receiving end (downhole). Both transmitter and receiver arrays are coupled to the tubular conduit. Beamforming techniques are used along with power amplifiers to generate directional, high power and low frequency acoustic guided Lamb waves along the wellbore to transmit power over long distances. A downhole multi-channel acoustic energy collecting system receives the transmitted acoustic signal, and generates electrical power and stores the power in downhole electrical power storage. This power is used to operate downhole well equipment including sensing, control and telemetry devices.