An expander is the heart of an ORC or steam cycle device as it converts the thermal energy into mechanical power in order to spin a generator for the production of electricity.


There are several technical solutions in the market to achieve this conversion, like turbines, screw expanders, scroll expanders and piston engines.

The core of the Termo2Power technology is the patent pending own designed “rotary lobe” type expander.

Due to pressure difference between the inlet and the outlet of the expander, the lobes in the cylinders move into the opposite direction of each other providing shaft power.

Because of the embedded hermetic shaft seal and the applied bearings the Termo2Power expander can operate with all type of gasses like;
Air – natural gas – refrigerants – siloxanes ( silicon oil vapor ) as well as saturated steam

The operating conditions are temperatures from 0 °C  – 300 °C and pressure range 1,5 – 40 bar.


The difference with other type of expanders is that the Termo2Power expander performance is related to pressure differences and not to mass flow.

As a result of this technology, the applied temperature range is much wider than of its competitors and one single expander design can be used for all type of gasses, while for instance turbines need a different blade design for each different type of gas.

Depending on pressure, the capacity range for a single expander can be from 10 – 250 kW, but connected with transmission belts or other coupling solutions the expanders may be connected to a single generator of up till 1 MW.

Therefore the operational power range for a single installation is as wide as from  10 kW – 1 MW.

Termo2Power SA owns a complete precision tool machine park what makes the company independent of 3 rd parties and allow us to customize all type of solutions within above mentioned boundaries.


The generators used are all self exciting synchronous type, like from piston engine gensets allowing to operate in “island mode” as well as grid tied solutions with inverters.

Rotation speed s of the expander are controlled by the in-house developed “automatic frequency controller” and not by the external grid.  Standard speeds are related to the generator size and frequency 1500 – 1800 rtm or 3000 – 3300 rtm (50/60 hz )