Modern energy storage systems that efficiently use and store surplus energy from their own PV systems are a key building block on the road to CO2 neutrality. Founder and owner Georg Nicklas launched the transformation project around six years ago. The ESN mission: Fossil-free and CO2-free production!

Using surplus electricity instead of being switched off

Many companies that have invested in solar or wind power plants are faced with the problem of making optimum use of the energy generated in their own operations. Unneeded electricity often has to be fed into the public grid, and at peak times of power generation the systems even have to be throttled back or switched off completely. This was precisely the challenge faced by ESN. “We see how often we are switched off. That’s why we want to reduce our grid fees and increase self-consumption through regulated peak shaving of atypical grid usage and the use of intelligent energy storage systems,” says Thomas Säger, describing the main motivation. “In this way, we prevent surplus electricity from being lost or fed into the grid unnecessarily,” continues Säger. The new energy storage systems offer a flexible and sustainable solution here.

The right partners make the difference

With the interchangeability of the battery modules, STABL inverter technology is unique. “Thanks to the interaction of remote monitoring and replaceable modules, we can guarantee a very high level of reliability, which also significantly reduces maintenance costs,” explains Markus Weiss, Project Manager at STABL Energy. The combination of robust technology and well thought-out integration into the energy storage system is an important part of the strategy. Rene Kohl, an electrician at EGEN who is responsible for the ongoing operation and maintenance of the storage system, is particularly pleased about this: “Thanks to the individual battery cell replacement, we can act very quickly and replace ageing battery modules at the right time.”

Another project partner, EPC service provider Greenflash, helped to implement an intelligent energy management system for ESN. Greenflash planned, procured and installed the transformer station, took care of the low-voltage connections to the storage systems and set up the medium-voltage connections to the existing transformer station of the ground-mounted PV system in order to harness the energy from the storage system. “With our GreenX1 controller and AI-based energy management, we synchronize battery storage, PV generation, site consumption and exchange electricity prices to ensure maximum efficiency in complex energy systems,” explains Lennart Oklitz, Project Manager at Greenflash.

Bureaucratic hurdles are part of it

A number of bureaucratic challenges were also overcome. Henry Malsch, Head of Facility Management, mentions a detailed fire protection concept in particular, which required the construction of appropriate fire protection walls between the individual containers. Complex building regulations and approval procedures for the building application also delayed the project somewhat. Nevertheless, the planning and installation of the energy storage systems was completed quickly and efficiently: Less than 12 months passed from the project kick-off at the beginning of 2024 to the installation of the four containers. The storage units are expected to be connected to the grid in spring 2025. The close coordination with authorities, specialist planners and project partners proved to be crucial in order to implement all requirements quickly and in a legally compliant manner.