A wireless power and communication unit for field devices is configured to connect to a field device and provide operating power and wired digital communication between the unit and the field device. RF circuitry in the unit is configured for radio frequency communication. In one embodiment, power supply circuitry in the unit includes one or more solar power cells that convert solar energy into electricity to power both the unit and the field device. The unit interacts with the field device in accordance with a standard industry communication protocol. The unit communicates wirelessly with an external device, such as a control room, based upon the interaction with the field device.