Abstract: Techniques for cogeneration of heat and power are disclosed. A cogeneration system includes: a conduit loop configured to carry a working fluid using a Rankine cycle; a valve system disposed along the conduit loop, including valves configured to manage flow of the working fluid through a chamber; a backflow vapor line disposed along the conduit loop, configured to direct working fluid in a gaseous state to the chamber, such that the working fluid in the gaseous state displaces working fluid in a liquid state in the chamber and the working fluid in the liquid state advances through the conduit loop without requiring a mechanical pump; and a heat exchanger disposed along the conduit loop, configured to extract heat from the working fluid and direct the heat to a practical use.