Sea Litter Critters is a compact, unmanned, renewables-powered and self-sufficient vessel able to pick up marine litter and to treat it on board for volume reduction and energy recovery.
Problem to be solved
Coastal and marine human activities, from tourism to transport by ship, generate considerable quantities of waste, which has the potential to contaminate the marine environment. This type of waste ends up as marine litter, which enters the marine and coastal environment directly or it is transported to the sea and coast from land by rivers, draining or sewage systems or winds. Because of the continuum nature of the sea, marine litter occurs worldwide in densely populated areas as well as remote regions such as the Antarctic, in oceanic gyres, on shorelines and in the deep sea. It affects the whole water column from the surface to the seabed. It causes environmental problems (death of marine animals by entanglement and ingestion; smothering of marine vegetation and corals; contamination of sea environment by toxic components released through break up; transport of alien species etc.), economic problems (reducing the recreational value of water and coast therefore attractiveness for tourists, affecting fishing and fish farming, damaging boats) and social problems (pollutants and toxins entering the food chain through ingestion by sea creatures, from plankton to larger fish, with consequent effects on human health). Globally, it is not known with confidence how much litter is currently within the sea system nor how much is entering the sea annually, although a report published in January by the Ellen MacArthur Foundation states that in a business-as-usual scenario, the ocean is expected to contain one tonne of plastic for every three tonnes of fish by 2025, and by 2050, more plastics than fish [by weight].
At European level, marine litter is considered one of the indicators of the Good Environmental Status of the seas (Descriptor 10 of the European Marine Strategy Framework Directive ) and a specific workgroup has been set up to define the monitoring protocols while Member States initiate actions on awareness raising and minimisation activities. Each Regional Sea sees local communities/NGOs organising initiatives on a voluntary basis, like clean up days or litter fishing. From those, different types of litter are found, depending for example on the use of the sea and the morphology of the basin: the Mediterranean sea, highly trafficked by cruises/ferries and with popular beaches has on average mostly litter derived from tourist activities and up to 80% of the litter originates mostly from land, while the North Atlantic, highly trafficked with commercial boats, has mostly litter deriving from either fishing activities or loss of cargo. All studies highlight that plastic is the most common type of material found amongst the litter items, be it household items to fishing gear lost at sea. This poses a major problem as plastic is a persistent and pervasive pollutant: in such a harsh environment, plastic items become brittle and break down into small particles, but basically never dissolve. The particles can be eaten by zooplankton thus bringing toxins into the foodchain. Therefore, actions to prevent plastic entering the sea (minimisation of waste, use of biodegradable plastic, awareness raising) as well as actions to minimise the effects it has on the environment are required. Picking up litter while it is still intact, like through beach clean up days or the KIMO’s Fishing for Litter initiatives, helps in reducing the risk of plastic breaking down into finely dispersed particles, as well as mitigating the effects, e.g. on the recreational value of the coast, and raising awareness. Alongside these high profile environmental initiatives, there is evidence of stakeholders, particularly from the tourist sector, taking matters on their hand: Local Authorities organise themselves, often in cooperation with local retailers, hotel owners, beach facilities managers etc. and organise services to collect beached or floating litter within a few meters from the beaches. For example, the Municipality of Celle Ligure, on the Ligurian sea, whose beaches have been awarded Blue Flag status every year since 1996 and that has in place an Environmental Management System certified under ISO 14001, has organised a sea sweeper service, i.e. a small motorboat equipped with a net for collecting floating debris in the sea a few meters from the beaches. This vessel is deployed three times a day on the nearly 2km-long coast pertaining to the municipality. This service collected 3,650kg of litter in 2014, up nearly 50% from 2013 (2450kg) and cost to the consortium set up to promote tourism in Celle nearly 10,000EUR per year.
Objectives of the feasibility study
The project intends to explore the feasibility of introducing to the market a compact, autonomous and self sufficient litter collection and treatment vessel based on a patent pending device treating waste with plasma technology and no harmful emissions. This device is designed to operate near the shores especially nearer tourist facilities (beaches, marinas etc) substituting the mechanical collection of litter currently adopted or for clean-up operations after atmospheric events bringing unwanted solid material into the sea, offering also the opportunity for litter and other environmental data monitoring activities. With a litter pick up system able to collect floating litter of every dimension and an on-board shredder, it would be suitable to treat most sizes of waste collected from the top water column. It will have specialist combination of "vision" technologies to scan the sea surface and provide information for defining the navigation path for most efficient litter pick up. Sea Litter Critters will utilise an electric motor, suitable for a cruise speed of a few knots, powered by a battery pack recharged through solar panels, windpower and a generator utilising the syngas produced by the thermal treatment.
This vessel will be first of all developed for working near the coast in normal sea conditions or in rivers (including estuarine areas) and lakes, therefore it will have a suitable flat shape for shallow waters. It will be deployed for daily pick up service of the debris coming into the sea/waterway from everyday land activities or for extended/extra clean up operations after medium/small storms affecting the coast or for cleaning-cum-monitoring missions. As a further development, the hull shape could be further studied, alongside an overall reinforcement and suitable protection of the equipment on board, to make the vessel able to withstand the much harsher conditions of the high seas, for deployment in missions nibbling away at the waste patches within the oceanic gyres. Further developments will also concentrate on the collection system to adapt it to pick up sank waste near the coast, microparticles and liquid waste (oil spills), all the while taking into account minimisation measures to avoid bycatch and damage to the sea environment.
