Open-source software is intended to simplify network management

June 18, 2026

Source: E & M powernews

Controlling decentralized energy systems is considered a key challenge of the energy transition. A new open-source solution aims to overcome existing technical hurdles.

An increasing number of decentralized generation and consumption systems must be integrated into the power grid. However, a lack of reference solutions and complex communication standards have so far hindered the development of interoperable energy management systems. A new open-source solution aims to overcome these hurdles. The Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE), the energy storage manufacturer Fenecon, and the “OpenEMS Association e. V.” have jointly developed a reference implementation for this purpose. The OpenEMS Association coordinates the further development of the OpenEMS energy management system.

At the heart of this development is the integration of the open-source library “jEEBus,” developed by Fraunhofer ISE, into OpenEMS. According to the project partners, this creates a freely available reference implementation for communication between smart metering systems, control devices, and energy management systems. In the future, manufacturers will no longer have to develop the necessary interfaces entirely on their own.

The “jEEBus” library provides key software components for this communication. This will allow developers to draw on existing functions rather than programming the interfaces themselves. According to Fraunhofer ISE, the components are now available as open-source code on “GitHub”—a platform for collaborative software development.

The importance of such solutions is growing in line with the requirements for controlling decentralized systems. To enable grid operators to comply with the provisions of Section 14a of the German Energy Industry Act (EnWG), smart metering systems, control devices, and customer installations must communicate reliably with one another. According to Fraunhofer, the complexity of the standards and the lack of reference implementations have so far hindered the development of interoperable products.

An Open Foundation for EMS Manufacturers

The “EEBus” protocol is used for communication within this infrastructure. Among other things, it connects heat pumps, wall boxes, battery storage systems, inverters, and energy management systems. Through these communication channels, grid operators can limit the electricity consumption or feed-in power of individual systems as needed. Such interventions are provided for, for example, under Section 14a of the EnWG or Section 9 of the Renewable Energy Sources Act (EEG).

Project Manager Stefan Wursthorn of Fraunhofer ISE explains that the goal is to make complex communication standards easier to use and to develop solutions for the digitalization of the energy system in collaboration with the industry. The project partners also highlight greater transparency, traceable processes, and broader compatibility with existing and future systems.

Fenecon Plans to Introduce the Feature in FEMS

The FEMS (Fenecon Energy Management System) energy manager, based on OpenEMS, is scheduled to receive the new feature by mid-year. This should reduce the workload for installers. Thanks to the EEBus interface, there is no longer a need to run an additional cable to the meter cabinet, explains Senior Product Manager Alexander Stöger.

The project partners have already conducted an initial field test at the Fraunhofer ISE’s “Digital Grid Lab.” There, they transmitted a control command in accordance with Section 14a of the German Energy Economy Act (EnWG) through the entire communication chain—from the smart metering system through the control device to an OpenEMS-based energy management system. According to those involved, the test was successful.

The partners are planning further tests and the development of a joint roadmap for the summer. The focus will be on flexibility management. According to the project partners, the energy management system plays a central role in this, as it can control and optimize the operation of generation and consumption facilities within the limits specified by the grid operator.

Author: Davina Spohn