What is Rank®? Rank® equipment is based on organic Rankine cycle (ORC) technology. It allows the combined electrical energy and useful heat production using a low-temperature heat source, with the associated economic and environmental benefits.

The difference between a high temperature heat pump and an Organic Rankine Cycle system. A heat pump upgrades lower temperature heat source and lifts it to a higher temperature, whereas the Organic Rankine Cycle (ORC) converts waste heat to power (mechanical or electrical).

The working principle of the organic Rankine cycle is the same as that of the Rankine cycle: the working fluid is pumped to a boiler where it is evaporated, passed through an expansion device (turbine, screw, scroll, or other expander), and then through a condenser heat exchanger where it is finally re-condensed.

In this process, the surroundings work on the fluid, increasing its enthalpy (h = u+pv) and compressing it (increasing its pressure). On the other hand, the entropy remains unchanged. The work required for the compressor is given by W_Pumps = H₂ – H₁.