An energy conversion device includes a container body configured to hold a liquid; a housing affixed above the container body by a handler connected to a surface of the container body, wherein a primary roller is configured to rotate at a first end of the housing and a free roller is configured to rotate at a second end of the housing; a piston attached at a first end to an outer perimeter of the primary roller; an inflatable balloon attached to a second end of the piston within the container body, wherein vertical movement of the piston causes the primary roller to rotate; an air chamber configured to supply air to a lower opening in the inflatable balloon via a balloon valve; and an interconnect located on a side of the free roller configured for connection to one of an energy-driven device or a turbine generator.