Siemens Energy has acquired specialised organic Rankine cycle technology from insolvency administrators managing the assets of Maxxtec AG and Adoratec GmbH in Sinsheim, Germany. The purchase agreements have been signed and the transaction will soon be concluded. The organic Rankine cycle (ORC) is a thermodynamic process which uses fluids with a lower boiling point than water – such as silicone oils, refrigerants or hydrocarbons – as the working fluid, which allows electrical power to be generated economically from lower-temperature sources. Siemens has by this purchase expanded its portfolio of ‘environmental’ products and solutions.
The ORC process is used when the available temperature differential between the heat source and heat sink is too low to drive a steam turbine operated on steam generated from water, and can significantly reduce overall generating costs because it allows waste heat that could otherwise not be viably to be used for conversion into electricity. It also enables natural heat such as that from geothermic sources to be utilised as well as thermal energy generated by biomass combustion. Siemens will initially supply products and components for biomass-fired and waste-heat recovery plants with outputs of 2 MW. Over the medium term, geothermal plants with electrical generating capacities of up to 5 MW will be added to this product range.

"Combined with our long-standing experience in building small turbines, we want to utilise this pioneering organic Rankine cycle technology to tap into new markets," states Markus Tacke, head of the Industrial Power Business Unit at Siemens’ Energy Sector.