A sensor comprises a sensor element configured to provide a sensor signal representing at least one measurand detected by the sensor element, an electrical circuit configured to process the sensor signal to form a data signal, a photovoltaic cell configured to provide electrical energy for the sensor element and the electrical circuit, and a housing, in which the sensor element, the electrical circuit and the photovoltaic cell are positioned, the housing including a recess in which the photovoltaic cell is positioned, and a rim surrounding the recess and protruding beyond the photovoltaic cell. A method is also provided.