With the help of electric propulsion in the marine industry, more ships can get their daily resupply of fuel and other essential components. This means that they can operate more efficiently and can stay in the water longer. Both maritime and shipping companies are now looking at electric propulsion as a viable solution to solve a host of problems. In fact, many of them are already implementing some of the latest magnet technology into their existing fleet of ships.

For example, you may have a specific job to fulfil with electric propulsion where normally one generator set is sufficient. However, due to safety reasons you cannot rely on one single engine. With starting a second set you add safety. But, at the same time both engines are running at low load which means that the engines are running less efficient as they consume more fuel for each kw of power delivered. Also, at low load the exhaust gasses stay low which can cause fouling of the internal system. Exhaust gas treatment systems are usually requiring sufficient heat at their inlet so the chemical process of exhaust cleaning can be used. In such situations, a set of batteries could be allowed as additional set of power, serving as a large UPS that is capable of supplying propulsion power. 

How Battery Storage through a hybrid system can help…

At the start of the day, the power management system can handle the power demand on a single generator (blue line in lower graph). At increasing power demand, a single generator is not capable of delivering power. And the second engine is started. Now both generators are load sharing. Both engines run repeatedly at low load after which load is increased to 55-60%.

With a hybrid solution, it is possible to use the batteries to fill in the periods when power demand is high. During phases of low power demand the batteries are charged again. The second engine is not required. The first engine runs at 55-70% load. The batteries are used as a power buffer, and thus, maximise the operational efficiency. 

How does a Hybrid Solution look to an engineer?

The engineer’s dashboard presents the state of the installation in a logical way and focusses on readability, using large symbols and quiet colors where possible. Each battery set shows you the status of actual charge level and power delivered or charging power. The central power meter is designed by Van der Leun to inform the operator in an easy way to read about the status of the power plant.

Safety First

Using bright colours on the dashboard help to minimize risk and improve safety for the crew. The picture below gives you a real-life example of sailing on batteries only. It is to demonstrate that the operator is warned long before the battery charge level is exhausted. The symbols representing the batteries changes color first to yellow and red. Then power management requests for power reduction. In case the navigator would not respond the system changes back to generator operation to prevent blackouts.

To inform the ship’s operator about the status of the battery system, the automation system collects all data and presents it onscreen. From these pages, it is possible to connect and disconnect the batteries. Detailed information is available via the side window. Thus, the system is easy to navigate around and makes it simple to operate. 

Power Management System Interface: