‘Circular Explorer’ – by oeoo & Holcim
21. July 2021 2023-07-02 9:07‘Circular Explorer’ – by oeoo & Holcim
The ‘Circular Explorer’ is the latest waste collection ship from oeoo. It was implemented in cooperation with the global building materials group Holcim. Click the logo to go to the Circular Explorer project website

The ‘Circular Explorer’ is the latest waste collection ship from oeoo. It was implemented in cooperation with Holcim, a global leader in innovative and sustainable building solutions.
Formerly called ‘SeeKuh II’, the project was launched in Lübeck in 2019 and is a completely redesigned collection ship. The collection system of the ‘Circular Explorer’ is no longer based on lowerable nets, but on conveyor belt technology. Via deflectors at the bow of the catamaran, the marine litter is directed onto the conveyor belt mounted in the middle. The ascending belt continuously conveys the material onto a horizontal sorting belt. Everything that does not belong in the sea is sorted out manually by the sorting staff and collected in transport bags, so-called big bags. Harmless organic waste falls back into the water at the end of the conveyor belt through an opening in the deck. In this way, oeoo expects a higher efficiency and at the same time the sorting out of organic material and possibly animal by-catch is possible.
As SeeKuh I the ‘Circular Explorer’ has a modular design, so that it can be dismantled and transported in sea containers to any place in the world. The ‘Circular Explorer’ is 12 metres long and about 8 metres wide. This means that it can be stowed in only 2-3 overseas containers. The draught is only 0.8 metres and the weight is six tonnes. Its cleaning capacity is about 30,000 m²/h.
‘Circular Explorer’ is the world’s first waste collection ship of this size to be powered entirely by solar energy. Vertically and horizontally swivelling solar modules are mounted on a so-called carousel, which can be aligned with the sun.
The system can fully charge the two batteries with 32 kW within one day, as used in a BMW i3.
Until October 2021, the Circular Explorer was on its way in the Baltic Sea to recover ghost nets from the sea and was present as an ambassador for the protection of the oceans at the Climate Week and at “Wetter.Wasser.Waterkant” in Hamburg.
Please find enclosed our video on the Circular Explorer and the concept behind it from Holcim and oeoo.


In the shipyard hall of Lübeck Yacht Trave GmbH, the first solar-powered waste collection ship was built, including the solar panel, which is currently being transported here for assembly.

The rotating and swivelling solar panel of the Circular Explorer before assembly.

The almost completed catamaran is launched on the premises of Lübeck Yacht Trave GmbH.

The almost completed catamaran is launched on the premises of Lübeck Yacht Trave GmbH.

The Circular Explorer, not yet painted, on a first test drive.

The Circular Explorer on its journey from Lübeck to Hamburg.

The Circular Explorer with the solar sail that supplies it with energy.

The Circular Explorer on the day of its christening on 21 July 2021 in Hamburg’s Sandtor harbour.

Decorated and flagged: the Circular Explorer at its christening.

Christening ceremony of the Circular Explorer with a large audience.

From left to right: Günther Bonin, founder of oeoo, Jan Jenisch, CEO of Holcim, Bertrand Piccard, environmental activist and Nils Liebich, project manager of Circular Explorer.

The naming ceremony: Godmother Magalie Anderson, Chief Sustainability and Innovation Officer at Holcim, swings the bottle and…

…christens oeoo’s modern solar-powered waste collection catamaran the “Circular Explorer”.

The Circular Explorer on a test run – completely solar-powered.

Later, plastic waste is transported on board by conveyor belt…

Plastic balls symbolise the waste that is later taken out of the water by conveyor belt to be pre-sorted directly on board.

Plastic balls symbolise the waste that is later taken out of the water by conveyor belt to be pre-sorted directly on board.

Powered by solar energy, the Circular Explorer manages a top speed of almost 10 knots (approx. 18 km/h).

The Circular Explorer has a cleaning capcity of 21,000 sqm/h (approx. 3 football fields) and a waste collection capacity of 4,300 kg/day.
The Swiss Solar Impulse Foundation of the adventurer Bertrand Piccard has certified the Circular Explorer with the label “Efficient Solution”.
The non-profit organisation, founded in cooperation with the Swiss Federal Institute of Technology in Lausanne, is committed to protecting the environment.
To apply for the Solar Impulse label, companies must fill out detailed application documents and go through the application process certified by Ernst & Young , in which a network of over 400 experts tests solutions to ensure that, compared to the standard product, process or service on the market, they protect the environment while promising economic success.
The Circular Explorer from oeoo and Holcim meets these required criteria. Circular Explorer is presented on the Foundation’s website.
