When would you recommend an Organic Rankine Cycle over a conventional steam Rankine cycle?

Organic Rankine Cycle (ORC) uses organic fluids with lower boiling points than water, making it ideal for low-grade heat sources (80-300°C) where steam cycles are inefficient or impractical. Applications include waste heat recovery from industrial processes, geothermal power, biomass plants, and solar thermal systems. ORC advantages include single-phase heat transfer, positive-slope saturation curve (no superheating needed), lower operating pressures, no erosion concerns, and smaller turbine sizes for same power. Working fluid selection (R245fa, R134a, pentane, siloxanes) depends on temperature levels, safety, and environmental regulations. ORC efficiency is lower than steam but enables energy recovery otherwise lost.