Mr. Borgmeyer, you founded Energy Farming around 30 years ago, at a time when working with renewable energy was truly pioneering. What convinced you to take this path back then, and how important is that foresight in today’s energy market?
Reiner Borgmeyer: Even then, I could see the incredible pace of technological progress. I started with 150 kW wind turbines. By the time I founded Energy Farming in 1999, capacity had already increased to 1.5 MW. This represented a tenfold increase in performance compared to when I first joined the industry. I realised then that renewables were capable of forming the foundation of our energy supply. In the ’90s, we were still being ridiculed by the ‘big players’ in the sector. Today, we build plants with a capacity of over 7 MW, representing a fiftyfold increase. The fact that over half of Germany’s electricity now comes from renewable sources demonstrates the central importance that our industry has achieved. This foresight is more critical today than ever before; by adding storage, we gain the decisive building block to truly achieve an energy transition.
Which current project, in your opinion, best demonstrates how to build future-proof plants that will make us independent?
Jens Strebe: A very interesting example is the repowering of a large wind farm in Badbergen, Lower Saxony. Eleven new wind turbines are currently being erected there. Our vision is to expand this site, which has been operational for over 25 years, by adding photovoltaic panels and storage facilities immediately afterwards. This will transform the wind farm into a genuine ‘energy park’. It is hardly conceivable to operate economically there without storage, given that we are confronted with negative electricity prices, as is the case at many PV sites. We must consider the concept of electricity usage from the outset, whether for battery storage or for hydrogen production later on.
When and for what reason did battery storage become relevant for Energy Farming, and what prompted you to invest in storage projects?
Reiner Borgmeyer: Back in 2014, I said that storage would be the ’next big thing’ after photovoltaics. Unfortunately, German politicians have missed this opportunity over the last 15 to 20 years. The catalyst for our current project was the discovery of old grid connections in Melle (near Osnabrück) that were no longer needed for wind power. We asked the grid operator if we could install storage there. That was two years ago, before the huge wave of storage applications swept across Germany. We are now implementing 3 x 3 megawatts there.
Which experiences from planning large-scale battery storage projects have been particularly formative for you, permanently changing your view of the implementation of such projects?
Reiner Borgmeyer: We found that the market was highly fragmented. It was hard to tell which of the many providers and suppliers in the large-scale battery storage sector were reliable. Rather than three or four major established players, there are numerous smaller companies offering similar products. It was a valuable lesson for us to learn that you need technical expertise, such as that provided by NOVUM, to help make decisions, not just based on gut feeling.
What role should battery storage play in the future of Energy Farming’s portfolio, and what are your medium- to long-term strategic goals with it?
Reiner Borgmeyer: Storage systems are much more than just a supplement to wind and PV for us; they are the key component in completing the energy transition. Our strategic goal is to dispel the common misconception that green electricity is only available when the wind is blowing or the sun is shining. Storage systems make renewables reliable and available on demand.
Jens Strebe: In the medium to long term, our aim is to firmly integrate this technology into our energy parks. For now, however, it is crucial for us to gain valuable operational experience with our initial projects. We essentially have to ‘find our footing’ before we can routinely incorporate complex storage concepts into the grid.
Battery storage can be used in many different ways: grid-side, market-oriented, or closely linked to generation plants. What approach are you currently pursuing at Energy Farming and why?
Jens Strebe: We essentially distinguish between green and grey electricity operating modes. A classic green electricity storage system acts as a buffer for photovoltaic (PV) systems: the electricity is stored temporarily and fed into the grid at a later time. In contrast, grey electricity or arbitrage storage involves purchasing electricity on the exchange when prices are low and feeding it back into the grid when prices are high. A third option is grid-friendly use in exchange for a rental payment from the grid operator. Our ideal is a hybrid model: in summer, we use the storage system as a buffer for our own PV system; in winter, we make it available to the grid. However, as the regulatory framework and technical handling of such complex models are still in development, we currently tend to commit to a single concept to ensure that projects can be launched.
Reiner Borgmeyer: To illustrate this, I will give two examples: The most important area of application for green electricity storage is currently intercepting the ‘PV peak’. When exchange prices turn negative at noon in summer, a four-hour storage facility intercepts the electricity and makes it available at night.
A completely different usage scenario involves pure grid-side market orientation without your own generation plant. In the northern district of Osnabrück, we wanted to reactivate a former 30 MW substation in order to operate a pure battery storage facility there. However, we encountered a significant regulatory obstacle: since no energy is generated locally, grid operators refuse to approve load withdrawal. Currently, there are no regulations governing how such services can be safely withdrawn from the grid without local generation.
Value creation through PV peak shifting
The challenge: In summer, negative prices often arise on the electricity exchange between 11 a.m. and 3 p.m. During this time, plant operators often have to shut down their parks to avoid losses.
The solution: A 4‑hour storage system absorbs the electricity during this peak period, preventing the need for shutdowns.
The added value: The stored energy can be used at night, when the sun is not shining and prices rise again.
What specific challenges did you face when acquiring and securing grid connections?
Jens Strebe: Although there are clear roadmaps for wind and PV, grid operators often lack experience with storage systems. There are no clear regulations for ’start-up curves’, i.e. slowly increasing the load. When we connect a load equivalent to an entire industrial park to the grid at the push of a button, it’s almost impossible for the grid operator to plan for that. That’s why they are extremely cautious. Today, new applications often mention time horizons of 10 years. Our project was approved two years ago, which was fortunate, perhaps also because it is comparatively small at 3 megawatts. Storage facilities are key to grid optimisation, but the grid connection point is currently the absolute bottleneck. Everything depends on legislative progress.
You implement your storage projects independently. What criteria do you use to select partners for this important role, and what motivates you to work with new providers who are willing to learn? To what extent has this approach paid off for you professionally and financially?
Jens Strebe: We look for partners who are interested in forming a partnership. Technical availability is the key success factor. In other words, guaranteed system readiness to deliver or absorb power exactly when the market or grid requires it. With such high investments, you only make money if everything runs smoothly.
Reiner Borgmeyer: It’s still too early to draw any final conclusions as we’ve only just connected the storage facilities to the grid and we haven’t gained any operating experience yet. However, we have definitely become smarter in technical terms.
How did Energy Farming become aware of NOVUM Engineering, and in which specific areas did NOVUM support you in planning and evaluating BESS projects?
Reiner Borgmeyer: We were introduced to NOVUM through word of mouth via our sister company, bioconstruct. Primarily from a technical perspective, NOVUM helped us to explore the market and understand the providers’ contracts.
Was there a particular moment during the collaboration that demonstrated the added value of external technical expertise?
Reiner Borgmeyer: Yes, absolutely. We had already been in talks with one supplier for a long time. Mandy Schipke from NOVUM then examined the contracts, as well as the offers from another provider at our sister company. Based on her recommendation, we switched to the other provider. Without this expertise, that probably wouldn’t have happened.
If you were advising companies that are investing in battery storage for the first time or entering this market, what would your advice be? What should they pay particular attention to?
Jens Strebe: Once the grid connection and approval are in place, it is crucial to have the contracts reviewed by a consultant. This is money well spent, given that many deployment models are still largely bespoke and risks are often distributed asymmetrically. It is important to look closely.
Would you like to learn more about how NOVUM can also provide technical support for your storage project?
