Schottel Hydro, a subsidiary of the Schottel Group, has announced the appointment of Niels Alexander Lange as Managing Director of the recently founded company, while also announcing the launch of the Schottel Instream Turbine (SIT), designed to harvest hydrokinetic energy for commercial projects at a reasonable cost.
Lange, 36, took up the post at the start of this year and will lead the company's activities in its three segments: the Instream Turbines (SIT), semi-submerged Triton platforms and components, such as turbine hubs and drives.
In 2011 Dipl.-Ing. Lange joined the Josef Becker Research Centre of the Schottel Group. The naval architect brought along his experience as researcher at the Institute for Fluid Dynamics and Ship Theory of the Hamburg University of Technology. Since then he played a major role in the development of the company's hydrokinetic energy devices.
"Our solutions provide a cost-effective way to harvest river current and tidal energy, both for utility- and community-scale applications," he explains. "Harvesting hydrokinetic energy is an attractive addition to the renewable energy mix. Schottel Hydro is already involved in several projects around the globe."
The new SIT is one development helping to exploit hydrokinetic energy. The SIT design purposely avoids complex subsystems, says the company. It features passive-adaptive composite blades with no need for any active pitch mechanism. Its drive train is standardized with a two-stage planetary gearbox and an induction generator. The ambient water ensures a steady operating temperature of the generator, thus no additional cooling mechanism is needed. An optional multi-disc brake is available for very harsh environments or to meet regulatory requirements.
"The simple turbine layout results in a robust and lightweight device," explains new MD Lange. "In contrast to other instream energy converters with nacelle weights of 130 t to more than 200 t, a single SIT only weighs about 1 t!"
SIT turbines are scalable in terms of quantity, depending on the required output. For example 1MW of installed power requires about twenty SIT turbines. The multi turbine principle therefore leads to an optimum ratio of power and material use. Each of the turbines is connected to a frequency converter feeding into a common DC bus installed on the tidal platform. The system thus includes redundancy and ensures a high availability of the power plant. SIT turbines are compatible with various support structures: fixed land-based, floating, semi-submerged or full submerged platforms are suitable.
Schottel Hydro identifies three flow speed standard classes for SIT applications. These classes result in three SIT rotor diameters of five, four or three meters optimized to the respective flow speed and application. Depending on the diameter and the current velocity, one SIT produces between 54 and 70kW rated, grid-ready electric power.
