How much power (kW)(Min-Max) is required for the electricity consumption on board of the tanker & container ship when docked at berth?

Question

Can someone help me on the below question:

How much power (kW)(Min-Max) is required for the electricity consumption on board of the tanker & container ship when docked at berth?

Tanker (Min: ) (Max: )

Container Ship (Min: ) (Max )

Answer 1

Depends on what is on, the size of the vessel and port accomodations for carbon emissions.

Once connected, shore power goes to the main switchboard so anything can be on. But typically lights, outlets, safety (fire pump, bilge pump) and monitoring equipment.

There is a limit to shore power transformer (100kW typical, but depends on port, up to 10-15MW), which allows the crew to do move around the ship, do maintenance tasks and unload/load the ship.

Shore Power

From link, lower voltages (450V and 690V) for smaller vessels requiring 100kW to higher voltages (6.6kV and 11kV) for larger vessels with >1MW loads. This applies to all classes of ships, including tankers and container ships. So the question cannot be definitively answered.

If more power is required than shore power can deliver, the crew must disconnect from shore power and power up a shipboard generator to drive the heavier load. In principle, the onboard generators could be paralleled to shore power, but this is never done because of the differences between ship power (possibly insulated neutral, ~60Hz, cathodic corrosion protection) and shore power (grounded neutral, =60Hz). It's expensive if you blow up the shore transformer!

This is complicated for container ships due to reefers (refrigerated containers), which can draw from 3kW (frozen) to 12kW (fresh fruit), figure 5-6kW. Many ports are moving to restricting ship emissions (reduce carbon footprint) in port, so shore power must increase to meet needs of loading/unloading (ballasting) and supplying reefer power. A 11,000 TEU container ship with 1,100 reefers means 3.3 MW to 6.6 MW fully loaded.

From Vancouver Shore Power:

Nominal Operation Voltage shore-side power supply: Three Phase 6.6kV A.C

Two parallel high voltage power cables each including three high voltage energized conductors, three pilot conductors, and one ground (earth) conductor, shall be used for HVSC systems up to a maximum power demand of 7,5 MVA.

Tankers have the same constraints. Big pumps to offload product. Largest electrical loads for tankers can be pumps. Reduced emissions means power comes from shore power, which is typically cheaper than burning fuel oil and cleaner since it can come from renewable resources.

From World Ports Sustainability Report 2020 showing the 66 ports with high voltage shore power.

So the answer depends on what is on, the type of ship and the size of ship. Min: 0. Max: approximately shore transformer capability.