As a part of forward-thinking environmental legislation, the Norwegian Parliament set out in 2018 to outlaw harmful emissions from the ferries and cruisers operating in its fjords by no later than 2026. This covers both CO2 and NOx gases, as well as noise pollution on the water.

The response from local shipping companies and ferry operators has been to dramatically accelerate the development and introduction of electrical propulsion systems. And the performance figures of Norway’s first all-electric ferry to enter service are, to say the least, more than impressive.

The MF Ampere, a fully battery-powered ferry, operates between the ports of Lavik and Oppedal, where shore-based charging stations recharge its batteries. Compared to diesel-powered alternatives, a 95% reduction in emissions and an 80% reduction in operating cost have been claimed for the vessel. This is an attractive proposition for ferry fleets worldwide.

Traveling relatively short distances and staying quay-side at the same ports for long periods of time, car and passenger ferries have proven to provide an ideal place to begin the inexorable shift from traditional diesel to battery and hybrid diesel-electric power in the global maritime transport sector.

A critical enabler in this radical transformation is the availability of the right types of batteries, in the right kinds of volumes to power the new all-electric and hybrid powertrains.

In opening a flexible, highly automated battery factory in Trondheim, Norway, Siemens has invested NOK 100 million ($11.36 million) to help address the future demand. It will develop and manufacture energy storage solutions for both marine and offshore oil and gas applications.

To achieve the high levels of automation required from its new maritime battery production line, Siemens appointed Raufoss based Intek to provide the robots, 3D machine vision and automated system integration it needed to help achieve demanding productivity goals.

Challenges

In the case of an all-electric ferry, the battery pack generally needs to have a battery capacity of around 2 MWh. A typical configuration has 34 battery cabinets. Within each there are 9 battery modules, with each comprising 28 battery cells. Even in a hybrid diesel-electric power system, a battery capacity of at least 500 kWh is needed.

As well as car and passenger ferries of course, there are thousands of fishing boats, cruisers, multi-purpose vessels and offshore units that can also benefit from full or part electrification. Demand for marine battery sets, and the production capacity to support it, is therefore expected to be high and set to rise exponentially.

Head of Siemens’ offshore and marine centre in Trondheim, Torstein Sole-Gärtner said, “All car and passenger ferries in Norway will ultimately rely on some form of energy storage solution, and we estimate that there’ll be around 60 hybrid or all-battery powered ferries operating here.”

Siemens expects a doubling of the global marine battery market by 2024 and predicts nearly 80% of all new ships up to 150 meters in length will be equipped with either all-battery or hybrid diesel-electric configurations.

To keep pace with future demand, the new Trondheim production line systems needed to be as efficient and flexible as possible. The number of people involved hands-on in the production process would need to be minimized, while the amount of robotization needed to be maximized.

Olaf Pedersen, Project Manager at system integrator Intek, outlined the challenge faced. “Maintaining rapid, error-free production throughput was a vital consideration in developing the overall solution,” he said. “Whether the production task was transporting components, product assembly or test, assuring high productivity was key.”

Handling battery component parts in the production line’s depalletizing section presented a particular set of challenges. Pedersen explained, “Unlike the other production cells, the first cell needed to be able to automatically handle a wide and unpredictable range of components – battery cells, frames, connectors and so on…”

“The handling of so many different kinds of in-coming goods, arriving randomly placed on palettes, on cardboard trays and in plastic blister packs for example, and to do it at some speed can be a tricky task to automate.”

Solution

Siemens’ Trondheim maritime battery production line is equipped with eight independently configurable robot cells, and seven automatic guided vehicles (AGVs) for handling inter-cell logistics. Designed and engineered by Intek over a 12-month period, the line handles everything automatically, from the initial picking of component parts through to final battery testing and documentation.

For the depalletizing cell, Intek chose to use the Zivid One real-time 3D machine vision camera mounted on a KUKA KR9 robot arm equipped with a custom designed vacuum gripper. A Siemens programmable logic controller and a high-speed industrial PC provided control and processing power. Intek applied its own custom algorithms to manipulate the camera’s 3D point cloud data and maximize production line throughput.

“By harnessing the Zivid One camera’s high-quality 3D point cloud we were able to easily pinpoint the outline of the pallet or tray, very accurately determine the outer dimensions of the component within, and then pick-and-place accordingly with the highest degree of accuracy,” said Pedersen. “And being able to rely on a single camera snapshot meant it was very fast, too.”

“By taking this more pragmatic approach we could resolve the issue of random component alignment without the need for any mechanical ‘steering’ systems or operator intervention to straighten up the components and shift them to predefined positions. What’s more, it also avoided the need for intensive programming of complex component CAD files. It’s a very flexible and reliable solution as a result.”

“Because the robot arm is automatically stacking component parts onto a relatively small AGV, it’s essential that the system takes into account distribution of load – the AGV needs to be stay perfectly balanced in transit,” said Peterson. “Furthermore, when the AGV arrives at its destination production cell, the component parts need to be picked by another robot from predefined positions. And so accurate component placement onto the AGV was also essential.”

Results for Siemens

The advanced cellular nature of Siemens’ maritime battery production line enables it to flex its capabilities and increase its production capacity in response to the expected upsurge in worldwide market demand and rapid technological developments. Battery design and production is more easily tailored to match a particular vessel’s function and duty cycle.

By harnessing state-of-the-art machine vision, robotics and AGVs, the Trondheim production has achieved a high level of automation, requiring only three people to work in the production area. It makes it possible to produce sustainable energy solutions more efficiently and cost-effectively.

With its highly-efficient, end-to-end automated production line, Siemens is expected to be able to supply batteries for 150-200 ferries annually, equating to a battery module capacity in the order of 400 MWh. The factory can produce the battery modules needed for an all-electric ferry in less than four days.

The positive environmental impact of the switch from diesel-powered vessels towards all-battery or hybrid vessels cannot be underestimated. Reductions in CO2 and NOx gas emissions and water-borne noise pollution will be felt globally as well as locally. Emission-free, near silent maritime operations are a worthy goal to aim for.