Here’s a sobering statistic, courtesy of German environmental non-profit One Earth-One Ocean (OEOO): by 2025, the total amount of plastic in the ocean – currently estimated to be 5.25 trillion pieces – will outnumber fish. In other words, we’re going to need a lot of waste-collection vessels to clean up this mess.
In turn, OEOO has launched a solar-powered, rubbish-recycling catamaran, dubbed Circular Explorer, which will play a small but crucial role in the drive to remove plastic waste from nearshore and coastal areas. The aluminium craft made its debut in the Baltic Sea in late 2021, where it was tasked with retrieving abandoned fishing nets from the water. Working in partnership with the Scientific Diving Association, and spending 2,000 man-hours at sea, OEOO used the boat to recover more than 1,000m2 of fishing nets and 2,000kg of marine litter.
The craft was built by Lübeck Yacht Trave, with components supplied by building materials manufacturer Holcim Group. Functioning as both a clean-up vessel and a floating lab, the 12m x 8m Circular Explorer weighs 7tonnes and has a depth of 1.8m and a draught of 0.7m. The boat can collect up to 4,300kg of trash daily, with a clean-up rate of 21,000m2 per hour. “During daily operations, up to five crew members operate the vessel,” Holcim tells Ship & Boat International.
Holcim and the builder worked with OEOO’s engineers to develop the boat’s rubbish-collecting conveyor belt, which is lowered into the water to collect plastic waste. This waste is then gathered on board and manually separated into recyclable and non-recyclable piles. Circular Explorer is also equipped to undertake water-sampling and mapping of microplastic pollution.
The boat has a pretty neat green powertrain too. Roof-mounted solar panels, spanning 60m2, convey clean energy to two BMW i3 40kWh batteries, which feed twin 50kW Torqeedo electric outboards – providing enough energy to power the boat and all of its systems. The solar panels can be tilted by up to 33° and are 360°-rotatable, enabling them to follow the sun. The arrangement gives the boat a service speed of 3.5knots, increasing to 9knots max, and virtually unlimited range as long as there is daylight. Holcim says: “The boat is designed to operate on coastal waters and rivers, as the extraction of marine litter will only work at wave heights below 1m.” This will enable the craft to play a crucial role in cutting off streams of trash before they flow into the ocean.
As of 2022, Circular Explorer will be deployed in Manila Bay, the Philippines, to focus on tasks such as: cleaning and recycling; providing education regarding the pollution problem; and undertaking scientific R&D projects. The vessel is designed for a service life of 25 years, after which its aluminium hullform and superstructure will be recycled.
