It is a high-tech facility where everything is just about right. With outstanding architecture, a clearly defined purpose and state-of-the-art technology inside, its new digesters are, therefore, characteristic of Würzburg wastewater treatment plant. In the future, 4,500 tonnes of sewage sludge will be produced each year, with an almost tripled annual capacity of 10,000 cubic metres. This means more digester gas and more power generation. 4.2 million kWh of additional electricity can now be produced to be consumed directly on site. As a result of this measure, the CO2 balance improves enormously and the odour nuisance is also reduced. A focal point of the electrical engineering was the integration of the generated energy with the Mainfranken network in line with the Renewable Energy Sources Act. Specifically, the lightning protection system was a considerable planning challenge. Here, it was necessary to, on the one hand, adapt the components of the new digesters and, on the other, to protect their design membrane and the potentially explosive areas against lightning strikes. DAHLEM was responsible for the electrotechnical planning for all service phases.