The European Green Deal sets ambitious targets to reach net zero emissions of greenhouse gases by 2050

To reach this goal, the European community must rethink the use of resources and energy into a sustainable and circular economy.

The European Green Deal sets ambitious targets to reach net zero emissions of greenhouse gases by 2050

To reach this goal, the European community must rethink the use of resources and energy into a sustainable and circular economy.


There is a large potential for incorporating batteries in the waterborne fleet if these challenges can be tackled.

For example, electrification of vessels operating on shorter routes with the option to regularly recharge or by including batteries into hybrid solutions that allow vessels to cover large distances by drawing power from both batteries and conventionally powered engines.

FLEXSHIP Concept for electrification of vessels by optimization of large battery electric power systems within fully battery electric and hybrid ships

Objectives and ambition

The overall goal of FLEXSHIP is to develop and validate safe and reliable, flexible, modular, and scalable solutions for electrification of the waterborne sector. This includes the reliable design and development of modular battery packs; safe on-board integration including the battery system and its associated electrical distribution grid into the vessel’s existing power grid; optimal design of energy management system (EMS) to maximise the operational flexibility (of different vessels under different operation scenarios) and energy efficiency (of both full-electric and hybrid solution), and smart control for improved lifetime of the battery system and critical power components.

The solutions will be relevant to electrifying various vessels with two main approaches:

1  Short sea shipping with full-battery propulsion where the power demand of the vessel is 1-2MW.

2  Extended ranges with hybrid battery propulsion for larger vessels with propulsion power of 10-20 MW.


The overall project goal will be achieved by the following specific objectives and key project results:

Objective 1

Design, verify and validate onboard electric grid and control architectures that can be scaled and adapted to the needs of various vessel types and operating conditions.

Objective 2

Develop a modular, scalable battery system that can be optimized to the needs of different vessels and operation conditions and has high reliability and safety, long lifetime, and low weight.

Objective 3

Testing, verification, and system integration of flexible and safe onboard electrical configurations.

Objective 4

Demonstration of FLEXSHIP solutions onboard two full-scale vessel demonstrators and evaluation of the demonstrators’ performance for two use cases:

1) R/V Gunnerus operating fully electric with 1MWh battery capacity on routs of 50 to 100nm.

2) Atatürk operating in electric-hybrid configuration with 3MWh battery capacity on routes of 100 to 300nm.

Objective 5

Evaluation of the sustainable operation of the FLEXSHIP solutions, reduced noise and emissions, and roadmap to fully electric operation on routes of 300 nm by 2027.

Objective 6

Dissemination and exploitation of FLEXSHIP’s technology through a business plan and strategy for development of skills and technology transfer.


FLEXSHIP will develop and validate large battery system integration innovations for the waterborne sector and will push the technology up the TRL ladder starting from TRL 4/5 and ending at TRL 7.

The key challenges that will be address are safe integration of systems onboard, the reliability, availability and efficiency of the battery system, and the redundancy of the system.

FLEXSHIP will demonstrate innovations that go beyond the state-of-art for the following elements:

Green Digital Twin scheme for design and validation of electrical grid architectures for fully electric and hybrid electric vessel.

Safe integration of large batteries onboard of vessels to ensure interoperability of systems.

Safe and reliable battery systems that can be scaled to match the vessel needs and space/weight limitations

Monitoring of system operation (BMS, EMS, PMS) to ensure high efficiency, availability, redundancy, lifetime, and compliance with future needs for both fully electric and hybrid-electric vessels

Strategy for long term skills’ development needs and technology transfer

The target groups that benefit from the FLEXSHIP technology are the following:

The maritime sector compromising of shippers, ship operators, ship builders, suppliers, maintenance and repair companies will be able to use the FLEXSHIP solution to electrify there existing fleet (retro-fitting) and design new vessel with high-capacity battery systems integrated in the vessel electric grid architecture.

The maritime organizations and port authorities will be able to use the FLEXSHIP results related to standardized charging solutions to ensure that the port infrastructure needed for the wide-scale adaptation of electrification in the waterborne sector is meet.

The European public will benefit from FLEXSHIP in form of access to more sustainable transport systems that do not rely on fossil fuels but are driven by electrical systems with lower noise and emissions (e.g., pollutants).

Universities and research institutes will continue to develop their expertise on electrical systems and the use of these in the waterborne and other transport sectors ensuring that Europe stays at the forefront of the green transition and can inspire the global community to adopt sustainable energy solutions around the world.

The objectives will be achieved by 8 WP
and 16 partners within 48 months

In WP1 identification of specification and
mapping of requirements will be done.

In WP2 the vessel electrical architecture will be designed and optimized by means
of the Green Digital Twin.

In WP3 the development and optimization of individual components and sub-systems will be done and the testing of the system at component/sub-system level will consist of hardware-in-the-loop (HiL) and software in the loop (SiL) tests in WP4.

The full FLEXSHIP system will be tested in two demonstrations in WP5 with minimum 150nm sailing distance and in WP6 contributing to 300nm by green digital twin and achieving sustainability analysis and business plan.

In WP7 the full system will be evaluated in an exploitation strategy. The innovations will be brought from TRL4/5 to TRL7.

FLEXSHIP Work Package structure


The main interactions between WPs, tasks, and deliverables are presented in the pert diagram