Yokes from the Allgäu Facilitate Rotor Blade Installation at Wind Farms of Leipziger Stadtwerke and eab New Energy GmbH
Königshain-Wiederau/Memmingerberg (jm).
Saxony is driving forward the energy transition, and the innovative powerhouse ematec from Memmingerberg in the Allgäu is at the forefront. Thanks to the RBC-D 50 yoke developed by ematec, in collaboration with Leipziger Stadtwerke, Saxon wind park specialist eab New Energy, and ENERCON, Germany’s largest wind turbine manufacturer headquartered in Aurich (East Frisia), a significant wind farm project has been completed. In two construction phases at Königshain-Wiederau (district Mittelsachsen), the project partners installed two wind turbines of ENERCON’s new EP-5 generation. These E-160 EP-5 E3 turbines now supply renewable electricity with a rated capacity of 5.6 MW each, sufficient for up to 9,000 households. Two additional turbines are currently being constructed at the Kleinschirma wind farm, approximately 40 km away.
Milestones on the Road to Climate Neutrality
“Königshain-Wiederau now hosts the first wind farm independently developed by Leipziger Stadtwerke – in collaboration with highly professional partners,” says Dr. Maik Piehler, Managing Director of Leipziger Stadtwerke, adding, “We are proud of the result. It enhances our diversified energy mix, increases the security of supply for residents, and contributes towards greater climate neutrality.” The plant provides green electricity for more than 9,000 households. Through its Energy and Climate Protection Programme 2030 (EKSP), Leipzig aims to reduce per capita CO2 emissions from 5.18 tonnes (2020) to 0.25 tonnes by 2040. Harnessing wind energy is one of 60 measures planned by 2030 across seven action areas.
Indispensable
During rotor blade installation at Königshain-Wiederau wind farm, turbine manufacturer ENERCON once again relied on the safety and reliability provided by ematec’s yokes. “The RBC-D from ematec has become indispensable in our installation process. It offers complete process reliability and significantly accelerates the installation process. This was impressively demonstrated at Königshain-Wiederau,” says Matthias Jöde, ENERCON’s responsible project manager. Jöde particularly appreciates the practicality of RBC-D technology from the Allgäu region: “Our rotor blades can be flexibly mounted at various angles using ematec’s yokes. With numerous sensors on the yoke, we always have complete control and can correct any deviations immediately in real-time. If predefined thresholds are exceeded, the system stops automatically,” explains Jöde.
RBC-D and APS: A Proven Combination
At Königshain-Wiederau, ENERCON also employed the proven combination of RBC yoke and the Autonomous Positioning System (APS) from Seasight Solutions. Here, two propellers are attached to the ematec yoke, allowing rotor blade installations without taglines. “This is a game changer as we can now avoid using winches, drastically reducing space requirements,” says Jöde.
Less Downtime on Construction Sites
This represents pure process optimisation: traditional methods allow rotor blade installation up to wind speeds of 8 m/s, whereas the RBC-D-APS system permits installation at speeds up to 10 m/s. “On average, APS saves us 2.3 days per construction site, days that would otherwise be lost due to weather conditions,” explains Klaas Schumann from ENERCON’s Site Engineering.
Impressive Performance
The combination of RBC-D and APS also delivered as expected during the project of Leipziger Stadtwerke and eab New Energy GmbH. “Single-blade installation went remarkably smoothly. Considering the initial foggy conditions, the performance was impressive. There were no downtimes or idle periods. Congratulations to Matthias Jöde and his team for installing each set of rotor blades in just one and a half days without issues,” says Lara Forsans, project manager at Leipziger Stadtwerke.
Transportation was the Biggest Challenge
For Forsans and her team, alongside colleagues from eab New Energy, installation wasn’t the most significant challenge—instead, it was the preceding approval process and logistical aspects of transportation. “Transporters had to manoeuvre the 80-metre-long rotor blades through tunnels and tight curves. It was quite spectacular,” Forsans explains. The last 13 km to the wind farm were completed using heavy-duty self-propelled vehicles.
Proven in Practice
Julian Eberhard, CTO of ematec AG, is delighted with the successful project of Leipziger Stadtwerke and partners. “It’s fantastic for us as a family-owned company from the Allgäu region to actively participate in Germany’s energy transition. It is a great honour that ENERCON, Germany’s leading wind turbine manufacturer, has trusted our technology for many years.”
Already 30 Yokes
ENERCON has ordered 30 RBC-D yokes from ematec in recent years, deploying them worldwide. Ematec’s RBC-D yokes continue to be in high demand in Saxony. For Leipziger Stadtwerke and eab New Energy, the motto remains: “After the project, there is the next one.” In Kleinschirma near Oberschöna, another wind farm with two E-160 turbines by ENERCON is currently under construction. The first turbine is already operational. “Installation here has again proceeded without any problems,” confirms Lara Forsans from Leipziger Stadtwerke.
About ematec's RBC-D Generation Yokes
The RBC generation rotor blade yokes from ematec are the world's first and only single-blade yokes that automatically and individually adapt to each specific rotor blade, consistently balancing themselves. They can handle blades ranging from 45 to 110 meters in length and stabilise them at inclination angles of up to ±30 degrees, ensuring uncontrolled movements are entirely avoided. The RBC system always identifies the precise centre of gravity for safe blade handling. Two counterweights at each wing of the yoke automatically adjust to the centre of gravity, with or without the blade.
The "D" in RBC-D stands for "Double," indicating that, in addition to the lower gripper, the upper telescopic gripper is also equipped with fourteen hydraulically actuated and gimbal-mounted grip pads.
Additional Highlights: The gripper hydraulic cylinders feature integrated safety valves that prevent blades from slipping out, even if improperly handled. With a hang height of only approximately 3.5 meters, the RBC series greatly simplifies crane management, particularly considering the increasing hub heights of wind turbines.
Ready for Action in Record Time
On construction sites, RBC yokes become operational faster than any other yokes, automatically moving into their working positions and attaching to the rotor blade at record speed. The RBC yokes require less than 30 minutes to complete these two steps.
The Green-Line variants of the RBC yokes are powered by high-performance batteries, suitable for mounting three rotor blades at temperatures as low as -20 degrees Celsius. Battery operation is double-redundant. Thanks to ematec’s Green-Line technology, wind turbine manufacturers can bypass stringent emissions standards, such as the Euro-5 and USA EPA Tier 4 final regulations, which have been effective since January 1, 2019. Additionally, ematec intentionally maintains the electric motor at a voltage below 48 volts, making it fully compliant and easy to deploy in the USA according to UL (Underwriters Laboratories) requirements.
With transport dimensions of approximately 14 m x 3 m x 2.95 m (length x width x height) and a net weight of about 27 tonnes (RBC-D 50), the yokes can be transported in Germany with a permanent permit under § 70 of the German Road Traffic Licensing Regulations (StVZO).