3 reasons electrification of ships makes sense

Electrification and hybridization of ships have been picking up in the industry for a while now, being the predominant choice for short-sea shipping.

There are several solutions on the market to choose from such as shore power connection, battery hybrid solutions, shaft generators, or alternative electric propulsion concepts.

At the moment, fully-electric ferries, RoRo vessels, inland vessels, and tugs are taking the stage as part of the decarbonization drive ramping up in the sector.

However, there are several considerations to be made before a ship-owner decides to go electric and is convinced that he/she made the right business choice.

The critical aspect to fitting batteries and hybrid solutions on board a ship is understanding the vessel’s energy consumption based on its operating profile in order to determine how to reap fruits from such installations. This also means that an operator has to implement the necessary operational changes to achieve the promised benefits of up to 20% power demand reduction, otherwise, the cost-benefit balance loses on its appeal.

Some of the key impediments to a greater uptake of hybrid and electric solutions has been the high cost, especially for retrofitting which can be four times higher than operating on cheap diesel, followed by lack of port infrastructure as well as limits to fast charging.

As the great minds of the industry seek to overcome some of these hurdles by introducing innovative solutions to the market such as swappable batteries to avoid the need to recharge or wireless charging, one thing is certain, electrification and hybridization of ships with battery solutions are here to stay. Furthermore, they should not be looked at as quick-fix solutions but rather from a long-term savings perspective.

Speaking at a webinar on Hybrid and all-electric: the next steps in electrifying the world’s shipping industry, hosted by Riviera Maritime, Torsten Büssow, Director of Electrical and Power Management Systems at Wärtsilä, shared the 3 key reasons why electrification of ships makes sense.

The first reason is the immediate reduction of greenhouse gas (GHG) emissions because when a vessel connects to a grid in a port, especially in Europe, it can turn off its auxiliary engines and thus pollute less while staying in the port. What is more, since around 50% of the power generated in Europe is believed to be green electricity, vessels using shore connections are likely to profit from this resulting in an immediate impact on the environment.

The second reason, Büssow continues, is lower propulsion losses when using renewable energy as the source of power for a vessel.

“Propulsion losses for fully-electric vessels are estimated to be a bit higher than 10 percent, which is far superior to any other propulsion means that we know,” he explained. “Therefore, to be blunt, every vessel in short-sea that can electrify will eventually do so, because propulsion losses are so small.”

The third reason would be ensuring flexibility with electrically-enhanced propulsion systems during times of uncertainty on the future operational profile of a vessel as well as availability of alternative fuels and power sources such as energy storage and fuel cells.

“What comes with it is a shift from an engine-centric propulsion setup towards a software-centric setup, where the software is at the center of a modern, multi-power source vessel. It is called energy management system, a new software category, which optimizes demand and supply of different power sources of a vessel,” Büssow added.

Even though still in its early stage of adoption, the primary driver for electrification and hybrid power on board ships have been fuel and Opex savings and return on investment on the long term.

In particular, this has been a popular solution for newbuilds as there is greater flexibility with regard to the installation process of the support system on board.

Nevertheless, with the IMO setting a clear path on the EEXI and CII requirements in the short term, electrification of ships could become a retrofitting option for owners who won’t slow down their ships in order to become compliant with the IMO GHG reduction target of 40% cut in 2030.

For newbuilding vessels this will mean introducing hybridized solutions on board that include electrical systems that will replace the standard low-speed diesel engines for propulsion and three auxiliary engines for generating onboard electricity, as these are optimal for a specific speed and power demand.

“Every newbuild, therefore, needs to carefully study alternatives to have flexibility built in that can support an operational profile that works for a 25-year vessel lifetime,” Büssow believes.

For example, Altera Infrastructure, previously known as Teekay Offshore, has invested in a series of six vessels featuring the E-shuttle design. The vessels use LNG as fuel as well as recovered volatile organic compounds (VOCs) as a secondary fuel. They will also feature battery packs for flexible power distribution and blackout prevention.

This means that shuttle tankers will not use auxiliary engines while sailing but will instead use two 4-stroke engines with controllable pitch propellers and shaft generators to produce electricity.

Similarly, Misje Eco Bulk AS, part of Norway’s ship owning group Kåre Misje & Co., has ordered up to ten eco bulk carriers from Sri Lanka’s Colombo Dockyard PLC (CDPLC). Each vessel will be powered by a four-stroke diesel engine with an electric hybrid system supplying additional power through a battery system.

Hybrid ferries are also taking shape quickly. Namely, Finnlines, a part of the Italian Grimaldi Group, is building three hybrid RORO ferries in China which will feature a hybrid power conversion system, including a 5000 kWh energy storage system that enable these ships to operate with zero emissions while in port.

Moving forward, the application of hybrid solutions and electrification on board is expected to push into the deep-sea shipping sector as well especially as the adoption of alternative fuels and fuel cells onboard ocean-going ships increases.

In order to move forward with these solutions, large ships will all need battery solutions to tackle the transit load behavior issue. So, whatever green fuel you choose for your deep-sea vessel it will need to be supported by a hybridized propulsion system, Büssow concluded.