System for determining and/or monitoring at least one state variable of a measurement object, comprising at least one analysis sensor, a control apparatus and a read-out apparatus, wherein the analysis sensor is configured to be introducible into the measurement object for remaining within the same, and to be sensitive to at least one ion type, and to generate measurement data in the measurement object based on a concentration of the ion type, wherein the control apparatus is configured to control the analysis sensor with respect to the generation of the measurement data, wherein the read-out apparatus is configured to read out the measurement data from the analysis sensor, and comprising a permanent individual network with a common central network node, wherein several analysis sensors that are sensitive to the same ion type or to different ion types exist, wherein the several analysis sensors are configured to be read-out via the common central network node, wherein the read-out apparatus comprises a first read-out unit and a second read-out unit, wherein the first read-out unit is configured as the common central network node, and wherein the second read-out unit is a mobile read-out unit disposed outside the measurement object and configured to communicate wirelessly with the first read-out unit introduced into the measurement object, wherein the analysis sensors and the first read-out unit are configured to be permanently buried within the measurement object, wherein the system further comprises at least one energy source that is configured to supply at least one analysis sensor with energy, wherein the energy source comprises at least one accumulator, and wherein the energy source is configured such that the accumulator is chargeable inductively. comprising at least one analysis sensor, a control apparatus and a read-out apparatus, wherein the analysis sensor is configured to be introducible into the measurement object for remaining within the same, and to be sensitive to at least one ion type, and to generate measurement data in the measurement object based on a concentration of the ion type, wherein the control apparatus is configured to control the analysis sensor with respect to the generation of the measurement data, wherein the read-out apparatus is configured to read out the measurement data from the analysis sensor, and comprising a permanent individual network with a common central network node, wherein several analysis sensors that are sensitive to the same ion type or to different ion types exist, wherein the several analysis sensors are configured to be read-out via the common central network node, wherein the read-out apparatus comprises a first read-out unit and a second read-out unit, wherein the first read-out unit is configured as the common central network node, and wherein the second read-out unit is a mobile read-out unit disposed outside the measurement object and configured to communicate wirelessly with the first read-out unit introduced into the measurement object, wherein the analysis sensors and the first read-out unit are configured to be permanently buried within the measurement object, wherein the system further comprises at least one energy source that is configured to supply at least one analysis sensor with energy, wherein the energy source comprises at least one accumulator, and wherein the energy source is configured such that the accumulator is chargeable inductively.