DC grids: The key to a flexible electricity system

Electric vehicles, heat pumps, and home storage systems are making our electricity system more flexible. It could be the breakthrough of a familiar technology: DC grids.

The German car may soon serve less as a status symbol and more as an energy storage device. E-cars can already be charged cost-effectively via the photovoltaic system on the roof. If electric cars one day release energy (which is already technically possible), they could be much more closely linked to the smart home and more efficient use of resources. The same is already true for heat pumps.

According to a study by “Agora Energiewende“, households in Germany could use around 100 terawatt hours of electricity, i.e. almost 15% of electricity consumption, flexibly over time by 2035. The DC grid is central to this. DC grids could increase the efficiency and flexibility of these technologies by enabling the direct utilisation of the direct current generated and reducing conversion losses. This would increase the overall efficiency of the energy system.

Direct current grids for German industry

This is not only interesting for households, but also for industry. “Direct current from renewable energies can be easily integrated into production and at the same time make an important contribution to greater energy and resource efficiency,” says Prof. Dr Holger Borcherding from the Ostwestfalen-Lippe University of Applied Sciences and scientific director of the research project DC-INDUSTRIE2.

Since 2016, more than 40 companies and research institutions have been working on solutions in the DC-INDUSTRIE and DC-INDUSTRIE2 projects to utilise the potential of direct current technology for industrial production facilities. The technology has already been successfully tested and applied in ten model plants and transfer centres. “The efficiency compared to alternating current is impressive: we have been able to save up to 20 per cent energy in some applications and reduce copper consumption in the cables by half,” says Borcherding.

Direct current on the rise in Europe

In 2022, the Association of the Electrical and Digital Industry founded the Open Direct Current Alliance (ODCA), in which 33 companies from industry, academia, and research are involved. The aim is to build a global direct current ecosystem and establish direct current technology across all applications. A similar initiative comes from the Austrian Electrotechnical Association (OVE). Its DC initiative has set itself the goal of providing Austrian companies with technological support in the development and research of DC products. Its aim is to contribute to maintaining European infrastructure sovereignty in the future use of DC grids.

These initiatives can be observed throughout Europe. For example, the DCC+G project coordinated by Philips Electronics Nederland BV, the Europe-wide Horizon Europe projects TIGON and READY4DC, or the German eMobiGrid project. In Austria, the NEFI project “Austrian DC Pilot Factory” is researching the benefits of direct current at the machine manufacturer “Fill” in Upper Austria. The company employs over 1,000 people. In a pilot test, Fill’s fleet of electric vehicles will draw electricity from its own photovoltaic system and supply it to production at peak times.

Understanding the future of direct current

At the NEFI Technology Talk on 23 January, experts from industry, research, and administration will talk about the potential of direct current for the economy. Representatives of the Austrian DC Pilot Factory Project, the OVE with its DC Initiative, and the German DC Industry Initiative will be among those present. The event is free of charge. You can find the registration link and the speaker panel here. https://www.nefi.at/de/news-detail/nefi-technology-talk-dc-industry We look forward to seeing you and to a lively exchange!