Battery and wireless sensor for temperature and fan control in connection with the receiving interfaces SRCx and highergraded control systems. Temperature measurement in gaseous media of heating, cooling or airconditioning systems (e.g. fresh air/ exhaust air ducts). Detection of measuring values via the highergraded control system. Transmission to receiver by means of radio telegrams according to EnOcean standard. With integrated temperature sensor and solar energy storage for maintenancefree operation.