Climate protection thanks to innovative technology at the Noerdlingen substation

Netze BW, Noerdlingen, Germany
The challenge

Power supply systems and climate protection must go hand in hand

Reconciling a safe, reliable power supply system with sustainable climate protection is extremely challenging in terms of technology. While power supply companies are redesigning their grids for tomorrow’s energy environment, the need for sustainable, eco-friendly solutions is also growing.
We value innovation and environmental protection very highly
Dr. Martin Konermann, Technical Director, Netze BW

Adapting its power grids is also a challenge for the EnBW subsidiary Netze BW GmbH. The expansion of wind and photovoltaic plants in particular requires that power grids be redesigned to easily accommodate and distribute the growing proportion of energy generated from renewable sources. The modernization of the Noerdlingen substation is an important step in this process that also fulfills EnBW’s corporate goals, of which sustainability and environmental protection are a fixed part, thus also making them a central responsibility of Netze BW.

The solution

CO₂-neutral high-voltage switchgear

Even before the energy transition began in Germany, power supply companies were increasingly focusing on the topic of sustainability. Thus the distribution of energy from renewable sources should ideally be climate-neutral. This requires innovative solutions that combine reliable technology, cost-efficiency, and eco-friendliness.

Siemens’ modernization of the Noerdlingen substation involved the expansion of the existing air-insulated switchgear and a new 110/20-kV transformer. The order also included retrofitting and expanding the existing air-insulated switchgear, including protection and control systems, as well as cable and overhead-line work.

The goal of commissioning in 2018 was not only to make the technology future-proof, but also to improve the company’s own environmental performance. However, a solution was needed that could replace the switching, extinguishing, and insulating gas sulfur hexafluoride (SF₆) that has been used worldwide for decades. The gas’s chemical and electrical properties are ideal for use in compact switchgear, but SF₆ has high global warming potential, which is why an alternative had to be found.

Clean-air technology

World’s first substation with SF₆-free switchgear technology in a 110-kV high-voltage grid

Backed by 40 years of experience in manufacturing medium-voltage vacuum tubes and with more than 5.5 million interrupter tubes delivered, Siemens introduced proven vacuum-interruption technology into high-voltage grids of up to 145 kV. Now, for the first time, it has been installed in a 110-kV grid belonging to Netze BW.

At the Noerdlingen substation, Siemens installed its new 3AV1 blue high-voltage circuit-breakers with vacuum-interruption technology and a combined voltage and current converter, including clean-air insulation, in a 110-kV high-voltage grid for the first time. The switchgear thus require no SF₆ switching and insulating gas. This innovative solution relies on a vacuum interrupter unit for switching and extinguishing the arc and on clean-air for insulation. Clean-air is technically prepared and purified air in a mixing ratio of 80 percent nitrogen to 20 percent oxygen.

Siemens has been using this technology in the medium-voltage range up to 72.5 kV for over 40 years. The new blue circuit-breakers achieve a rated voltage of 145 kV. They offer the usual performance as well as additional, superior features. “We’re constantly refining our products with a view to higher efficiency, safety, and environmental compatibility. This is reflected in our blue portfolio,” say Ralf Christian, CEO of Siemens’ Energy Management Division. “Our blue portfolio makes it possible to modernize and expand the existing power grids at the highest level of safety and to simultaneously reduce our ecological footprint to an enormous extent without having to compromise on performance and economic feasibility.”

One result of risk-free handling is that certain precautions are no longer necessary during shipping, installation, maintenance, and recycling. Nor is there any requirement to report the quantity of gas used in the devices.

I’m convinced that with this Siemens blue technology, we have ushered in a new era of high-voltage technology
Karlheinz Kronen, CEO Energy Management High Voltage Products, Siemens
Customer benefits

Maximum performance and minimal environmental impact thanks to blue technology

The products in the Siemens blue portfolio combine innovative, climate-friendly technologies, making it possible to implement a safe, reliable power supply and achieve positive environmental performance in a cost-effective manner.

The completely type-tested 3AV1 blue circuit-breakers have a number of features that are superior to those of SF₆ circuit-breakers, including 30 full short-circuit current interruptions, 10,000 rated current interruptions, 2-cycle current interruption, full performance at ambient temperatures between –60°C and +55°C, and freedom from maintenance during their entire lifetime. Clean-air technology is also risk-free in terms of possible regulatory changes.

Sustainable world premiere

Security of supply meets climate protection

With the modernization of the Noerdlingen substation, Netze BW and Siemens have paved the way to the future: Powerful, future-proof technologies ensure a reliable power supply for the region, while eco-friendly innovations enable operation that is both cost-effective and climate-neutral.