Energy Storage System Size Estimation for Hybrid Dual Fuel Powered Dredging Vessels
CEDA Dredging Days 2019
B.T.W. Mestemaker, H.N. van den Heuvel and M.B. Gonçalves Castro
Abstract: Dredging vessels usually operate near highly populated areas. This makes natural gas powered dual fuel engines an interesting option for dredging vessels as these emit less pollutant emission such as NOX, SOX and PM compared to diesel engines. However, dual fuel engines have a poorer transient response and change to diesel mode when exceeding the load change capability. The application of an energy storage system is a possible solution to prevent this engine mode change.
The type and size of the energy storage system depends on the task it has to perform. An energy storage system can perform several tasks, such as assisting the engine during transient loading, supplying additional power during high loads, powering a vessel during low load and functioning as a standby power supply for dynamic positioning. In this case, the energy storage system has the task to assist the engine during transient loading. For this task, the system should be able to deliver the power gap between the required power and the engine capability for the period it takes the engine to reach the required power level.
This paper discusses a method to estimate the size of the energy storage system based on a static analysis of the engine capability and the dredging system load requirement. A sensitivity analysis with the dynamic analysis methods investigates the effect of the proposed energy storage system on the engine's transient loading. This analysis includes several variations in both the power and energy capacity of the system. The validity of the static analysis method is evaluated with the results of the sensitivity analysis.
Keywords: Dual fuel engines, energy storage system, hybrid system, simulation models