Technology from Siemens will be used to transform the main wastewater treatment plant in Vienna, Austria, into a green power plant, using sewage gas to generate all the energy required for the wastewater treatment process.

The company said on Friday that it will supply the control, measuring, analytical and power distribution systems, as well as low-voltage and medium-voltage switchgear. The order, worth approximately EUR24 million ($25.4 million), includes migration and expansion of the existing Simatic PCS 7 process control system to the latest version, 8.1, and installation and commissioning of all the individual systems.

The plant is expected to use sewage gas to generate all of its energy by 2020, and the treatment process itself is also highly energy efficient, with reduced water content and double the solid content. This considerably reduces the energy consumed during anaerobic digestion and gas generation, Siemens said.

When the project is completed, the sewage plant should generate an output of 78 GWh of electricity and 82 GWh of thermal energy, saving about 40,000 metric tons of CO2 per year.

“Our conversion of the wastewater treatment plant into a green power plant makes a valuable contribution to both a responsible use of natural resources and to sustainable power generation,” commented Christian Gantner, director general of the Ebswien sewage plant. “The efficient technologies of our partner Siemens play a key role in achieving our ambitious environmental and climate targets.”

Wolfgang Hesoun, CEO of Siemens AG Austria, added: “An essential factor of success for achieving the environmental targets of a city are the measures that generate maximum ecological and economic benefit. On the basis of extensive analyses, we have managed, together with our customer, to develop a tailor-made solution that will help the largest environmental project ever undertaken by the city of Vienna to become a success. In doing so, we are focusing as much on energy efficiency, preservation of resources and sustainability as we are on smart technologies and networked systems.”