At first glance, one does not suspect how important the terrain in the Austrian Erlauf valley is in terms of industrial history. The valley in lower Austria is part of the so-called Eisenwurzen - the birthplace of the Austrian small iron industry. In Neubruck, in the 1820s, the industrialist Andreas Toepper, pioneer of Austrian ironmaking and inventor of the rolled sheet process, built the first imperially and royally privileged iron, steel and rolled sheet factory.
Even today, the Toepper Castle testifies to this heritage and its importance for the region. Hydropower played an important role in both the iron mill and the paper mill, which was later built on the same site. Until a few years ago, the old drainage channel of the paper mill and a wooden weir were still landmarks of regional industrial history.
In the middle of the 2000s, Ökowind GmbH from St. Pölten took over the weir - with the aim of constructing a new hydropower plant on the Erlauf. Ökowind GmbH, which until then had only operated wind farms in Austria, converted the weir into a hydropower plant with an output of 1100 kW and an average drop height of 8.7 meters.
"When planning the plant, we opted for an investment subsidy instead of feed-in subsidies," says Julian Weiss, project manager at Ökowind GmbH. "This decision also meant that we had to sell our electricity on the free market right from the start. So it was important to us that we could rely on different trading options in order to achieve the best possible price for our electricity production. This is particularly important when you consider the falling prices on the electricity exchanges. We therefore quickly opted for Next Kraftwerke, as the company was the first provider in Austria to network decentralized plants with the aim of both enabling electricity trading on the spot market and providing control reserve to the Transmission System Operator. The option to participate in different markets allows us to diversify our marketing risk".
The Neubruck hydropower plant markets electricity both on the spot market and on the control reserve market. Almost the entire output can be used to stabilize the electricity grid in the event of frequency fluctuations. "If required, the hydropower plant can be ramped down to 100 kW," explains Weiss. The hydropower plant is able to offer both tertiary and secondary reserve capacity. "The balancing energy activations last from a few seconds to a period of several minutes - often several times a day. The revenues from these cdeliveries of control reserve are an important aspect for us in marketing via Next Kraftwerke. This is financially very lucrative for us, even if it doesn't seem intuitive at first glance to get money for shutting down your plant," says Weiss. But in this way, the hydropower plant makes an important contribution to stabilizing the Austrian electricity grid. Thus it takes up the path of the industrial revolution in this region again and leads it into the 21st century: with the digitization of the decentralized energy revolution.