Just a theory and the device would have to be really efficient. Earth's velocity relative to the cmbr (cosmic background radiation) appears to be in excess of 600km/second. If we create a light scource directed at a receiver and positioned so that the receiver is moving in the direction of the transmitter the light frequency will be blue shifted. Light travels at a set speed. The transmitter is moving at the same speed as the receiver but the light is moving at a constant speed and exists independent of the scource. The receiver will bang into the light at 600km/s gain.