Industrial DC grids are already a reality. Companies can implement and operate them today and benefit from their efficiency. Schaltbau in Munich and Phoenix Contact in Blomberg demonstrate this through best‑practice examples.
From idea to implementation: What needs to be done?
Direct current is an increasingly important topic. Beyond stand‑alone solutions for charging parks and DC grids in commercial buildings, DC systems represent the future of industrial applications. In the context of the All Electric Society, where carbon‑neutral energy sources dominate, direct current emerges as a key technology with numerous advantages.
Whether retrofitting a plant or building a new one, the first step is to identify which loads should run directly on DC, including lighting and technical building utilities, PV systems, storage, and production equipment. The choice of storage technology and its installation location, whether centralized or near the relevant machinery, must also be evaluated. Another key factor is whether the plant will include charging stations for electric vehicles. “At the outset, designing a DC grid is no different from designing an AC grid,” says Matthias Unruhe, Director Corporate Facility Management at Phoenix Contact.
Once project planning is complete, implementation begins, raising questions about voltage ranges and component selection. For industrial applications, the Open DC Alliance (ODCA) provides a system concept that addresses many of these points.
Schaltbau and Phoenix Contact offer a broad range of DC‑capable components, and major hurdles, like high power‑electronics costs, have decreased significantly. Their close cooperation has already resulted in two DC production sites: the Schaltbau NExT Factory in Velden and the Phoenix Contact All Electric Society Factory in Blomberg.
Potential and the (initial) obstacles of DC technology
DC systems in production and logistics offer major energy‑saving potential. Dynamic loads like industrial robots can cut peak loads by up to 85% and boost efficiency by up to 20%. Large motors with frequency converters also benefit, as do DC sources, loads, lighting, and charging stations. Even so, the path from planning to implementation was difficult for the early DC pioneers.
When planning for the Schaltbau NExT Factory began in 2019, there were almost no suitable components or standards for DC technology. Grid operators also had little experience integrating DC systems into the public grid, and finding qualified planners and installers was challenging due to the limited number of experts.
The situation has improved in recent years, supported by intensive research and multiple pilot projects that tested DC solutions under real conditions. These efforts are now paving the way for broader practical implementation.
Phoenix Contact had similar experiences. “After our initial deliberations, one question remained: Where would we obtain the components?” says Matthias Unruhe. The company’s broad portfolio provided the solution, including TRIO HP power modules for DC grids and VAL‑MB DC surge protection. Phoenix Contact’s long‑standing research into direct current also enabled the early development of key components such as the ELR HDC miniature circuit breaker and the ArcZero DC connector, both now used in the All Electric Society Factory.
Ultimately, implementing DC systems is less complex than it may seem. With suitable components, regulatory progress, and growing expertise, especially through the Open DC Alliance, adoption is becoming increasingly practical. “Recent developments have made DC projects much easier to implement,” notes Schaltbau expert Christoph Neulinger. His pragmatic advice: “Just do it.”
The All Electric Society production building of the future
The All Electric Society Factory leverages the full potential of direct current, achieving maximum flexibility, efficiency, and stability by coupling all relevant sectors via DC. It also optimizes the entire energy chain, from generation and distribution to storage and consumption, since many of these areas already operate largely on a DC basis.
The DC grid is supplied with 700 kW from the AC grid, while PV‑connected DC/DC converters add 120 kW directly to the DC bus. Two branches feed production machines and recover regenerative energy from robots and drives. Ten DC charging points (2 × 150 kW, 8 × 60 kW) serve the parking area. Surplus energy is stored in the DC‑coupled battery system or fed back into the public AC grid via bidirectional converters. PLCnext Engineer manages sector‑level and overall DC grid loads. The ELR HDC safely switches DC loads, combining protection, switching, monitoring, precharging, and network capability. ArcZero DC connectors enable arc‑free plug‑in connections, while EMpro DC meters record all energy flows. The industrial DC grid also serves as a research platform and public blueprint.
The DC high-bay warehouse system
Logistics is another area where DC technology’s potential can be fully realized. Schaltbau’s automated small‑parts warehouse, with 50,000 storage locations and 5,000 daily transport operations, forms the logistics backbone of the NExT Factory. Ninety Autonomous Robotic Carriers support the latest expansion. The entire system, including the ARCs, is highly energy‑efficient, with a peak power of only 18 kW, far below the roughly 120 kW typical of AC‑based alternatives.
DC for forklift trucks
A key element of Schaltbau’s logistics concept is the integration of two bidirectional DC‑grid‑compatible chargers for its forklift fleet. These are developed together with Jungheinrich and Industrie Elektronik Brilon specifically for the NExT Factory.
Analysis shows that forklift trucks are often idle during each shift. The DC‑grid charging concept uses these idle periods for controlled battery discharge and grid feedback, boosting on‑site energy storage. This helps cut power peaks and increase PV self‑consumption. Dynamic electricity pricing adds further benefits: stored energy powers the building when prices are high, and the fleet’s batteries are recharged when prices are low.
This strategy not only lowers energy costs but also extends battery service life.
Read more about the All Electric Society Factory and DC grids.
