Inspenet, September 9, 2023.
The team from the German company Energyminer, made up of Chantel Niebuhr, Georg Walder and Richard Eckl, has developed a compact, submersible turbine called Energyfish capable of generating clean energy. Energyminer claims on its website that a set of 100 Energyfish can save around 2,300 tonnes of carbon dioxide a year , equivalent to offsetting the annual emissions of around 1,700 small cars.
These small buoy-like hydroelectric plants float between the depth and surface of rivers, taking advantage of the force of their current without disturbing life in aquatic ecosystems . The company’s key focus is to achieve “perfect harmony with nature”, generating “green electricity” to power more than 400 homes through these turbines.
Clean energy with Energyfish: this is how it works
Although the idea of generating clean energy continuously using the power of river water 24 hours a day is simple, bringing it to reality has involved overcoming several challenges for the company.
Energyminer highlights four key advantages of its technology compared to other similar solutions: its operation is discreet and practically invisible from the surface of the river; does not pose a threat to aquatic life, particularly fish; installation and maintenance are simple; and can work steadily all year round, regardless of weather conditions.
Likewise, the electricity produced by Energyfish is directly integrated into the local electrical grid, providing a low-voltage energy source available 24 hours a day , with a capacity of around 6 kW.
The installation of these turbines is simple, as it only requires securing the system to the river bed. No concrete structures or dams are needed, as the turbines are held in place by this clamping system and begin generating electricity. This installation process can be completed in a matter of weeks.
Subsequently, each small hydroelectric plant undergoes continuous 24-hour monitoring to verify its correct operation. The Energyfish is a compact underwater hydrokinetic power plant consisting of a rugged turbine system designed to continue operating even in the worst weather conditions.
In situations such as high tides or icing, the Energyfish automatically adapts by sinking to the river bed, where it remains safe while continuing to steadily generate energy. In this way, the company ensures that its initiative is resistant to any climatic conditions that may arise in different regions throughout the year.
Thanks to its design, this plant is designed to resist the presence of algae and other objects such as logs or sediment that could float in the water. Likewise, it has a front mesh that is located between the holding structure and the turbine , which prevents large fish from accessing the turbine, allowing only the passage of water. In this way, the installation is prevented from having a negative impact on the marine life of the river. As for smaller fish, they can safely swim through the slowly rotating rotors; If any fish come into contact with them, they will be gently deflected without harm.
Electricity for homes
Although it is described as a compact hydroelectric plant, it has dimensions of 3 x 2.4 x 1 meters and a weight close to 80 Kg. Therefore, it is necessary that the river where it is installed has a depth of at least 1 meter and a minimum flow of 1.0 meters per second. However, the maximum speed allowed is only 2.5 meters per second, which is considerably lower than the speed of the Ebro River, which reaches 27 meters per second.
However, the company does not rule out using this solution in larger, navigable rivers, in which case it would be enough to install the plants outside the navigation channel so as not to interfere with maritime traffic. As the only potential impact, Energyminer notes that the river’s flow speed experiences a slight decrease near the location of the hydroelectric plant, but this effect is temporary and the river recovers its original speed after a short 20-meter stretch.
The first prototype has already been installed in a river in Munich. The developers claim that a single such unit generates an average of 15 megawatt-hours per year, with a maximum output of 6 kilowatts. Furthermore, it is estimated that these hydroelectric plants have a useful life of around 10 years .
The company raises the possibility of creating groups of up to 100 Energyfish in larger rivers, which could generate an annual output of up to 1.5 gigawatt-hours, equivalent to supplying electricity for approximately 470 homes, according to its calculations. This level of performance can only be compared to that of large wind turbines.