Water is not just a means of subsistence, but also a means of production and a source of energy. In many parts of the world, however, there is no basic provision of this essential commodity. In automobile production, it is impossible to avoid using water, however – in washing processes in mechanical manufacturing or process cooling, for example. Volkswagen is aware of its responsibility and thus uses this valuable resource sparingly. Using water sparingly is also laid down in the Group’s environmental principles: three of the 22 environmental principles for production relate directly to the issue of water.
Volkswagen has participated in the Water Disclosure Project (WDP) since 2011. This nonprofit organization collects information on water management in a comprehensive annual survey, and analyzes and evaluates the data. Volkswagen is the only German automotive group to agree to publish the results. We are thus trailblazers when it comes to the disclosure and transparency of our careful use of water and newly developed solutions for sustainable water management. Furthermore, since 2013, Volkswagen has been the first automotive company in the world to support the CEO Water Mandate.
Volkswagen has set itself the goal of reducing water consumption per vehicle in all plants by 25% by 2018 compared with 2010. During the reporting period, we implemented numerous measures in the plants to do this, showing that we are reducing the overall pollution of bodies of water attributable to vehicle production and at the same time ensuring a secure water supply.
The Foshan plant was the first facility in China to be awarded the Triple-Star Green Building Award – the highest state award for environmentally friendly factory planning. Almost all waste water at this location is treated and reused using state-of-the-art membrane technology. In engine production at the Salzgitter plant, no industrial waste water is created either because waste water containing oil is separated into oil and water in vacuum evaporators. The water claimed in this process is used to prepare emulsions. This helps us save 30,000 m3 of water a year. We also use energy-efficient evaporators at other Group locations, such as the Slovakian plant in Martin or the Polkowice plant run by VW Motor Polska. We use the resulting distillates as recycled water and for cleaning. Additionally, the amount of liquid and dangerous waste containing oil is being reduced by up to 40%.
The significant requirement for cooling water in the industrial production of automobiles means that there is also considerable potential for water savings in this area. When a new combined cycle power plant was constructed in Kassel, a nanofiltration plant was commissioned that helps save water in cooling tower operation. Thanks to this nanofiltration plant, we can treat waste water containing salt so that the water can be reused, allowing fresh water to be saved and up to 70% less waste water to be discharged.
The waste water cleaned in Volkswagen’s sewage treatment plants meets the highest global standards. We guarantee this by using state-of-the-art biological waste water purification technology, for example in the Pune plant in India. There we use a membrane bioreactor: the combination of microbial breakdown and filtration through extremely fine membranes means that over 99% of all biologically degradable components can be removed from the pre-treated industrial waste water. Thanks to this process, the water can be reused at the site.
We are also proving the high quality of our sewage treatment plants and waste water in a cooperative project between Volkswagen Slovakia and Comenius University in Bratislava: together we have been breeding crayfish that are supplied with purified waste water from the Volkswagen sewage treatment plant. The water provides optimal living conditions for the threatened crayfish. Volkswagen is supporting the return of crayfish to their natural habitat by reintroducing the farmed animals into the wild.