New Hybrid Propulsion Solution for Small Vessels Saves Energy

The central feature of this new diesel hybrid propulsion is the capability to provide an extremely flexible and compact propulsion solution in the power range from 100 kW to 800kW. “The limited oil reserves and increasing environmental issues make people think about complementing conventional drive concepts in ship building with means of expanding efficient operation conditions”, commented Ernst-Christoph Krackhardt, Director Sales Commercial Ships within Siemens Marine Solutions.

Any thermal combustion engine only operates at best efficiency when it is operated as close as possible to the design point. Operating such engines at low loads or excessive load levels, is inefficient, produces excessive emissions and can also shorten its service life – thus affecting maintenance cost. By applying a hybrid set arrangement, e.g. the auxiliary thermal combustion engine driven modules (gensets) run at a constant speed, turning electrical generators that feed electrical power to the power grid, which powers the propulsion motor.

With an intelligent control solution the hybrid diesel-electric management system runs only as many diesel powered gensets as required to cover the power demand – always close to the diesel engines’ optimum efficiency while the electrical propulsion drive solutions enable the optimum power generation and distribution for different ship speeds, e.g. el. power demands.

Such highly efficient hybrid systems have been the driving force for years in cruise liners, specialized ships, such as offshore supply ships, patrol boats, ice breakers and research vessels.

Cost, weight, required space and complexity prevented vessels under 40 meters from reaping its advantages of less consumption, i.e. less cost, increased range, greater reliability, reduced maintenance, reduced emissions and simplicity of operation. Siemens now successfully closed the gap between large merchant and naval vessels and small commercial crafts. The SISHIP Eco Prop is the break-through integrated solution in the world which provides the benefits of Hybrid Diesel Electric Propulsion systems for smaller vessels traditionally powered by conventional mechanical propulsion systems.

“Operating a diesel engine at its optimum efficiency, independent of the required propeller shaft speed, can improve drive system efficiency and realize substantial energy and fuel savings”, Krackhardt stated. “This diesel electric hybrid propulsion solution is able to meet stringent environmental regulations for ships emissions”, and the installation, Krackhardt said, “is quite simple due to the plug and play-solutions, based on standardized products”.

The Siemens Industry Sector (Erlangen, Germany) is the world's leading supplier of production, transportation and building systems. Integrated hardware and software technologies combined with comprehensive industry-specific solutions enable Siemens to enhance the productivity and efficiency of its customers in industry and infrastructure. The Sector comprises six Divisions: Building Technologies, Industry Automation, Industry Solutions, Mobility, Drive Technologies and Osram. In fiscal 2007 (ended September 30), Siemens Industry generated sales of approximately EUR40 billion (pro forma, unconsolidated) with around 209,000 employees worldwide.

With the business activities of Siemens VAI Metal Technologies, (Linz, Austria), Siemens Water Technologies (Warrendale, Pa., U.S.A.), and Industry Technologies, (Erlangen, Germany), the Siemens Industry Solutions Division (Erlangen, Germany) is one of the world's leading solution and service providers for industrial and infrastructure facilities. Using its own products, systems and process technologies, Industry Solutions develops and builds plants for end customers, commissions them and provides support during their entire life cycle.