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EU project Space@Sea

Visionary project successfully completed

For more than three years, the GICON® Group, together with 16 other partners from science and industry, has been researching solutions for modular and sustainable floating platforms for use in the oceans. In this context, GICON® engineers developed a maintenance platform with a self-sufficient energy supply. The result is a floating platform anchored in the seabed which can provide living and work space for up to 32 people. As part of  another work package, the offshore cultivation of microalgae and its potential use in aquaculture and agriculture was investigated. Space@Sea was funded by the European Union's Horizon 2020 research and innovation program.

Floating islands as a future habitat at sea

Space@Sea explored an important question of the future during the project period from 2017 to 2020. Where can living and working spaces for Humans be built? The background of this question is, among other aspects, the ever-increasing global population and the limited land areas. Due to the increasing demand for renewable energies as well as food, new forms for living and logistics centers are necessary. One option could be for such centers to be created on floating platforms which are connected to each other and form a large U-shaped island. The segment platforms are rectangular shapes and 90 meters long. Initial tests in the research tank of the Dutch Maritime Research Institute Netherlands (MARIN) have shown that the system is operationally feasible. The mooring systems would be adapted based on the location of the artificial islands and anchored via piles.

Maintenance platform designed by GICON®

GICON® engineers had already reached a crucial project goal by the end of 2019. Under the leadership of GICON® project manager Dr. Frank Adam, the design plans for a maintenance platform were created, which would provide space for 32 people on two decks on 1,800 m². The main function of the platform is to assist with the maintenance needs of offshore wind farms far from the coast.

In the future, on-site maintenance, with easy access to storage of small spare parts and reduction of costs for ship or helicopter transfer, will be important. Together with the partners of the Development Center for Ship Technology and Transport Systems EV, the NEMOS GmbH, the Technical University Hamburg-Harburg, the ship designer ICE and the Chair for Wind Energy Technology at the University of Rostock (LWET), clear goals were set at the beginning of the work:

• a platform with a building that provides quality of life
• a platform which is energy self-sufficient
• a platform which limits motion on the ocean Surface
• a platform with a robust modular design

"As a location for our studies and development designs, we chose an area in the Mediterranean Sea south of France," Dr. Adam explains the engineers' approach, "It was important to find an environment that would be suitable for a wind farm." They also looked for areas with available grid connections as well as available dry docks for assembling the floating islands and buildings.

"We drew on experience from the oil & gas industry when designing the hubs. The idea was to create a balance between work and life," Dr. Adam said. The specialist division manager for offshore wind energy within the GICON® Group and his team designed a building on four columns which are mounted on the floating substructure with outer dimensions of 45x45m, an important cost factor for future use at sea. "The finishing touch is a light-flooded, green interior," says Frank Adam.

Making islands self-sufficient and independent from fossil fuel supplies

Falk Wittmann, department head for energy efficiency was responsible for the hub's energy supply. "We had to make the islands self-sufficient from fossil fuel energy sources. For this reason, we only looked at renewable energy sources in order to provide the platform's required electricity, heating, cooling and fresh water needs." The final concept anticipates that electricity will be generated, for example, by a wind turbine as well as solar panels and a wave generator. Heat for the work spaces is to be provided by heat pumps, because " heat, especially in the present case, is available from the seawater at any time and at a comparatively constant temperature level". For the production of fresh water, the concept includes the reprocessing of service water. Any surplus electrical energy is always stored using battery storage. In conjunction with a heat storage system also included in the system, the regenerative energy supply can thus be decoupled from energy demand in terms of time and balanced even over longer periods of time.

"Our analyses of the practical application have shown, that the battery storage units are never completely discharged, so that with our targeted energy mix we can cover the daily demand of the platforms at all times”, explains GICON® project manager Frank Adam.

Using microalgae to feed People

How is the food for the residents on the floating platforms provided? How does agriculture work on the sea? These are the questions addressed by another working group, led by GICON® experts Dr. Stefan Matthes and Dr. Martin Ecke. "In the first step, we investigated whether the most favorable location is on or next to the floating island, in order to ensure compliance with the high quality, health and environmental standards during the cultivation of the algae biomass." One of the most important findings was that agriculture also requires space at sea. GICON® is able to address this issue with the inhouse-developed GICON® photobioreactor. Due to its space-saving design and its fir tree structure, which is modeled after nature, it enables the growth of microalgae anywhere in the world. Years of development work could be incorporated into Space@Sea. "We utilize a flexible double-wall tube as major component of the reactor. The microalgae are cultivated in one chamber of the tube and kept in the second part in water.

"Experiments in the wave tank in Wageningen have shown that the double-wall tube is also suitable as material for 'floating reactor modules' without a separate substructure in a marine environment”, said Biosolar department head Dr. Ecke, focusing on the project results. "At maritime sites, seawater can be can be used for the temperature management of the reactor system, so that the photobioreactor can always be operated in the optimal temperature range, even if high intensity solar radiation naturally prevails there," adds Dr. Stefan Matthes. Another advantage for the cultivation of microalgae in reactor systems which float on the water surface is that "the waves provide the energy for mixing and cultivation, which should ultimately drastically reduce the energy required for the cultivation process."

World's first industrial unit in Cottbus in operation for more than a year

In order to test the application of the GICON® photobioreactor on floating islands at sea and to be able to replicate processes, GICON® inaugurated the world's first GICON® octagon photobioreactor at its Cottbus site in summer 2019. As division manager Dr. Martin Ecke explains, the design is intended to "ensure that even under fluctuating ambient conditions on the platform, caused by waves and potential fluctuations, the reactor functions hydraulically and balances itself independently." The world's first industrial unit has generated many insights during its first year of operation. "The operation enabled us to conduct investigations into bioprocess engineering issues," says Dr. Stefan Matthes. "Process variables such as nutrient management and dosing, automation, process water treatment, etc., were investigated under near-industrial conditions, which must be adapted and considered as factors for the joint operation of modular reactor farms specific to each plant." One scenario for the use of the GICON® photobioreactor on the floating islands could be the cultivation of microalgae for providing food to fish farms. These could serve as a food source for the inhabitants of the maintenance platform. The EU-funded Space@Sea project concluded after three years with a final meeting in early October 2020.

More information: spaceatsea-project.euspaceatsea-project.eu

Interview with the coordinator of the EU project Space@Sea: Maarten Flikkema