The ECOSHIP, a new concept for Short Sea Shipping, is under development in Sweden. This environmentally friendly ship is designed around the flexibility of diesel electric propulsion which makes it possible to optimise both cargo space and hull design for improved efficiency, lower fuel consumption and lower emissions. The Ecoship concept is being developed with modern electrical power plant and electric propulsion systems in mind. This means highly developed electrical distribution, advanced power management system and electrical power generation from low emission diesel electric generating sets complete with selective catalytic exhaust converter system.
With the new hull, the water resistance has been reduced by approximately 10 percent compared to a conventional hull design of the same size. The Ecoship has, however, a 0.3 m larger draught but the length and width are the same. Despite the fact that the new hull is more slender than that of a conventional ship, the Ecoship has increased dead weight due to a lighter construction of the ship and lighter engine room. The three major criteria of the Ecoship concept are:
1. low energy;
2. an optimum environmental adaptation;
3. an improved volume capacity.
The price of the Eco-ship is slightly higher than that of a conventional ship, mostly due to the diesel-electric propulsion machinery. The ship will be equipped with ten high-speed low-emission diesel engines each connected to a 428 kW generator running at 1800 r/min. These ten units will serve both – the propulsion machinery and auxiliary machinery. Propulsion pods and cargo pumps will use 690 volts while the other electrical systems and automation will use lower voltages 440 and 220 volts via rotating transformers.
There is no dedicated emergency generator but the plant is operating in such a way that one engine-generator unit is selected for this role according to service intervals, running hours etc.
All ten generating sets are automatically controlled through a computerised power management system, which ensures that the correct numbers of engines are in operation. The large number of engines makes it easy to keep each running engine efficiently loaded, between 70–90 percent, and idling is minimized.
The ship is designed in such a way that it can be built in a large-scale modular system. The system makes it possible to build the different parts of the and then put the parts together. The engine room, for instance, can be built and equipped in a hall and workshop and then be lifted onboard when the time is suitable.