A clinical oxygen supply device (100) adapted to supply supplemental oxygen to a patient, comprising an oxygen inlet section (110) with a first coupling unit (111) adapted to be releasably coupled to a standardized oxygen wall outlet (1), an oxygen outlet section (120) with a second coupling unit (121) adapted to be releasably coupled to an oxygen dispensing device (2) attached to a patient (3), and an oxygen flow control section (130) with a regulation unit (132) adapted to regulate an oxygen flow between the oxygen inlet section (110) and the oxygen outlet section (120) on the basis of a control signal is provided. Display means adapted to indicate at least one operating parameter of the clinical oxygen supply device, an energy conversion section (140) adapted to generate electrical energy from pressure energy of oxygen supplied to the oxygen inlet section (110), and an energy supply section (150) adapted to provide the electrical energy generated by the energy conversion section (140) to the oxygen flow control section (130) and the display means are provided. The clinical oxygen supply device (100) is configured as a battery-less device. A clinical oxygen supply system (1) and a method of clinical oxygen supply are also part of the present invention.
