SCHOTTEL lays focus on sustainability with new SRE EcoPeller
Ship owners are facing major ecological and economical challenges to meet the ever stricter requirements of emission quotas and environmental regulations. At the same time, the technical requirements of customers, such as maximum overall efficiency, excellent course keeping stability and exact positioning in DP operation, are significantly influencing shipbuilding.
SCHOTTEL is meeting these developments with a highly efficient and ecologically clean propulsion system developed primarily for open sea and coastal operating conditions: the SCHOTTEL Rudder EcoPeller (SRE®, EcoPeller®). The brand-new thruster has already been ordered for eight ferries to be built for two of Norway’s leading ferry lines.
Considerable investments in research and development
Propulsion expert SCHOTTEL invested heavily in research and development and conducted extensive trials of this new product in order to achieve optimal overall efficiency and ensure that the new propulsion system provides customers with many years of reliable service. Another objective was to offer ship designers maximum installation freedom when integrating the propulsion system into vessel design.
The first concrete plans to design a future-oriented Rudderpropeller go back to an innovation workshop that was held in 2013. At the start of the project phase, various propulsion variants were extensively tested in hydrodynamic model trials and in flow simulations using state-of-the-art CFD technology. Parallel to this, the entire mechanical power train was optimized with the goal of minimizing mechanical losses.
Innovative high-torque gears
The SRE is distinguished by its utmost efficiency and robustness that are unrivalled on the market. The HTG (High Torque Gear) gearbox technology developed and patented by SCHOTTEL plays a significant role here. The HTG enables bevel gears of the same dimensions to transmit up to 15 percent higher drive torque combined with high and balanced safety margins with regard to all known forms of damage to gearing. Despite the very high drive torque, it is possible to achieve significantly more streamlined underwater gearbox housings, thereby increasing the hydrodynamic propulsion efficiency.
Best values in overall efficiency and course stability
The characteristic design of the SRE offers unprecedented performance in terms of overall efficiency and course keeping stability. The EcoPeller thus ensures that its owner benefits from low fuel consumption and thus low emissions and operating costs.
Optimal integration into every hull
“In addition to the ecological and economical aspects, the product variability of the SRE EcoPeller was of particular importance to us. The earlier we get involved in the design phase of the vessel and tailor the propulsion system and the hull to one another, the greater the overall efficiency of the vessel. It was thus important for us to provide the ship designers with propulsion system variants that fit precisely,” explains Dr. Christian Strahberger, CEO of SCHOTTEL. The integration capability of the EcoPeller is characterized by the way all components of the propulsion system can be produced in customized lengths, thereby enabling optimal hydrodynamic integration into hulls of virtually every shape and size.
Low vibrations and noise emissions thanks to integrated electric motor
The SRE is based on the SCHOTTEL SCD design principle with a vertical electric motor integrated into the Rudderpropeller. This eliminates the upper of the two angle gears, thereby boosting the mechanical efficiency by two percent. Another advantage is the compact design resulting from the combination of motor and drive. In the absence of components such as shaft lines between the motor and the drive, installation into the vessel is made very easy and cost-effective for the shipyard.
On board, the space-saving EcoPeller offers unbeatable comfort thanks to low vibration and noise levels.
Flexible motorization of the vessel
With the SRE, no limits are placed on vessel design when it comes to the choice of motorization. In addition to a ready-to-install factory configuration with a highly efficient asynchronous electric motor, optionally available with a permanent-magnet motor, the EcoPeller can also be freely combined with other vertical electric motors according to customer requirements. Alternatively, a Z-drive solution for the electric or mechanical drive is possible, optionally also with the new SCHOTTEL Y-hybrid for a combination of electric and mechanical drives.
High degree of functionality in different applications and vessel types
The SRE EcoPeller is available in various sizes for power ratings between 1,000 kW and 4,500 kW. Available propeller types are FP (Fixed Pitch) and CP (Controllable Pitch). One option with the CP propeller is the full-feathering function which allows the propeller blades to be moved to a low-resistance position if required. In this way, individual propulsion units can be shut down completely while generating minimal resistance.
Clean operation for environmental protection
The EcoPeller is equipped with a SCHOTTEL LEACON seal monitoring system. Pollution of the seawater with consumables is safely and reliably prevented by means of an additional intermediate chamber with integrated monitoring. This enables early detection of wear resulting from system operating conditions, thereby avoiding unplanned maintenance.
Sustainability integrated into production
Anyone claiming to build environmentally-friendly propulsion systems cannot merely focus on the end product in his efforts to produce “clean technologies”. With the opening of a state-of-the-art development and production facility in Doerth in 2015, SCHOTTEL has incorporated ecological aspects into the entire product manufacturing process. The production shops in Doerth have a combination system for heating and ventilation that also filters exhaust air. The process heat generated in production is used to heat the production shops. The exhaust heat from the test basin is used for underfloor heating in the offices. Lighting is also regulated efficiently: generously dimensioned windows allow optimum use of daylight, above, the lighting in the rooms is automatically regulated.