NOVELTY - The system has hybrid tag comprising an active radio-frequency identification circuit (60), a passive radio-frequency identification circuit (80), and a memory unit (120). An interrogator communicates wirelessly with the passive radio-frequency identification circuit. A scanner (210) wirelessly communicates with the active radio-frequency identification circuit. The memory unit is accessed by both the active radio-frequency identification circuit and the passive radio-frequency identification circuit.    USE - Radio-frequency identification (RFID) system for monitoring and controlling photovoltaic solar panel and windmill power generation. Uses include but are not limited to ancillary device such as light source, environmental sensor, moisture sensor, water level sensor, and slow scan video imaging equipment used for identification of logs in timber operation, container in storage or transportation network, railcar and vehicle.    ADVANTAGE - The active circuit automatically enters a sleep mode to reduce the energy drain from the small integrally mounted battery. The active circuit can be awakened to perform normal sensor operations by the passive circuit. The passive circuit is widely used to directly sense temperature, moisture levels, water levels, light source operation, various identifications, installation dates, repair history, shipment routes, etc. The passive circuit permits reading and writing of data through a wireless link to the interrogator. The RFID tags can easily sense, control, log, and monitor electrical and identification parameters from the power source or power load device.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) hybrid radio-frequency identification tag; and    (2) method for storing and retrieving data.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the RFID hybrid system.    Active radio-frequency identification circuit (60)    Passive radio-frequency identification circuit (80)    Memory unit (120)    Scanner (210)    Concentrator (250)