ORC Engines

The growing concern over the future depletion of fossil flues and the effect on our environment has brought to light the ORC Technology for Low-Grade Heat Recovery. In ThermoDraft, we provide commercial and customized designed ORCs for industrial and marine applications. Under the stressing of fossil fuel prices and the need for clean energy generation, ORC technology emerges as the ideal alternative, since it reliably saves costs. ThermoDraft's ORC products range from 30 to 200 kWe while exploiting heat sources from 70 to 180 °C. Higher capacities can be achieved with multiple ORC units in parallel.

How it works

The Organic Rankine Cycle (ORC) is named for its use of an organic, high molecular mass fluid with a liquid-vapor phase change, or boiling point, occurring at a lower temperature than the water-steam phase change. The fluid allows Rankine cycle heat recovery from lower temperature sources such as biomass combustion, industrial waste heat, geothermal heat, solar ponds etc. The low-temperature heat is converted into useful work, that can itself be converted into electricity.

Centrifugal pump with magnetic drive

Brazed plate or shell & tube heat exchangers

Screw type expander

Regenerative inverter controlled operation

Conventional and new-generation eco-friendly refrigerants with negligible GWP and Ozone Depletion potential (ODP) may be employed, such as R1234ze(E) or R1233zd(E). Polyester oil (POE) with appropriate viscosity and compatible with the refrigerants is used for the lubrication of the expander, which operates at high temperatures.

how orc engines work



Solid biomass

Residual biomass as fuel for co-generation system, based on the ORC technology



Heat recovery from exhaust gas and/or cooling system for electricity production


Industrial processes

Heat recovery from exhaust gas and/or cooling system for electricity production

Solar panel

Solar energy

Heat recovery from exhaust gas and/or cooling system for electricity production


ThermoDraft develops air-cooled or water-cooled ORC engines, depending on the specific needs and the required electrical load.

Air cooled type

Water cooled type

Download brochure
ORC modelsORC-230ORC-470ORC-830ORC-1130ORC-1530
Nominal electrical production (kWe) 3060100150200
ExpanderTwin-screw rotary semi-hermetic expander
EvaporatorBrazed plate heat exchanger
Condenser (3 options depending on the heat sink) Brazed plate heat exchanger for fresh water-cooled units
Shell and tube heat exchanger with copper-nickel tubes for sea/salt water-cooled units
Finned tube heat exchanger for air-cooled units
Refrigerant R1234ze(E) or R1233zd(E) (depending on the waste heat temperature)
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