Hydromechanical energy storage and energy conversion device, comprising: - a water reservoir, wherein the water reservoir is configured in the form of a first container having a closable opening (11, 11a) for the admission and discharge of water to and from the first container, - a first float which is arranged in the water reservoir and can be lifted with the rising water level in the water reservoir from a lower position into an upper position and can be fixed in the upper position, - a first generator for converting kinetic energy into electrical energy, - a first energy transmission apparatus which connects the first float to the first generator and is designed to transmit kinetic energy between the first float and the first generator, - a securing device which is designed to secure the first float in the upper position, - a second container having a closable opening for admission and discharge of water to and from the second container, - a second float which is arranged in the second container and can be lifted with the rising water level in the second container from a lower position into an upper position and can be fixed in the upper position, - a second generator for converting kinetic energy into electrical energy, - a second energy transmission apparatus which connects the second float to the second generator and is designed to transmit kinetic energy between the second float and the second generator, and - a water storage container, wherein the closable opening (11, 11a) of the first container is connected to the water storage container in a water-conducting manner and wherein the second container is connected to the first container and the water storage container in a water-conducting manner. - a water reservoir, wherein the water reservoir is configured in the form of a first container having a closable opening (11, 11a) for the admission and discharge of water to and from the first container, - a first float which is arranged in the water reservoir and can be lifted with the rising water level in the water reservoir from a lower position into an upper position and can be fixed in the upper position, - a first generator for converting kinetic energy into electrical energy, - a first energy transmission apparatus which connects the first float to the first generator and is designed to transmit kinetic energy between the first float and the first generator, - a securing device which is designed to secure the first float in the upper position, - a second container having a closable opening for admission and discharge of water to and from the second container, - a second float which is arranged in the second container and can be lifted with the rising water level in the second container from a lower position into an upper position and can be fixed in the upper position, - a second generator for converting kinetic energy into electrical energy, - a second energy transmission apparatus which connects the second float to the second generator and is designed to transmit kinetic energy between the second float and the second generator, and - a water storage container, wherein the closable opening (11, 11a) of the first container is connected to the water storage container in a water-conducting manner and wherein the second container is connected to the first container and the water storage container in a water-conducting manner.